CHEMICAL ADMIXTURES FOR HYDRAULIC CEMENTS

This application claims the benefit of and priority to U.S. patent application Ser. No. 13/624,920, filed on Sep. 22, 2012, and Provisional Patent Application No. 61/538,396, filed on Sep. 23, 2011, both of which are incorporated in their entireties herein.

FIELD OF THE INVENTION

This invention generally relates to a new class of chemical admixtures for hydraulic cement compositions such as pastes, mortars, grouts and concretes. The cement compositions are comprised of Ordinary Portland Cement, or blended cements or non-Portland cements made with Supplementary Cementitious Materials (SCMs). The admixtures improve the properties of cement compositions, including setting, hardness, compressive strength, shrinkage, and freeze-thaw resistance.

BACKGROUND OF THE INVENTION

Ordinary Portland Cement (OPC, also known as Portland Cement) underpins modern construction technology and constitutes the second most manufactured product in the world. According to Struble et al., Introduction to Portland Cement, in Portland Cement: Composition, Production and Properties, pp. 1-47 (2011 ICE Publishing, 3rd ed.); Herfort et al., The Chemistry of Portland Cement Clinker, 2010 Adv. Cem. Res. 22: 187-194; and Jackson, Portland Cement: Classification and Manufacture, in Lea's Chemistry of Cement and Concrete, pp. 25-94 (2003 Elsevier, 4th ed.), U.S. and world production of OPC currently stands at 72 million metric tons (t) and 2.8 billion t respectively.

OPC manufacturing has the disadvantage of having a large ecological footprint; it requires large amounts of mineral, fuel and water resources, and is accompanied by the release of various pollutants. See, Huntzinger et al., A life-cycle assessment of Portland cement manufacturing, 2009 J. Cleaner Prod. 17: 668-675; Flower et al., Greenhouse gas emissions due to concrete manufacture, 2007 Int. J. LCA 12: 282-288; Marceau et al., Life Cycle Inventory of Portland Cement Manufacture, pp. 1-68 (2006 Portland Cement Association); Rehan et al., Carbon dioxide emissions and climate change: policy implications for the cement industry, 2005 Environ. Sci. Policy 8: 105-114; Worrell, Cement and Energy, in Encyclopedia of Energy, pp. 307-316 (2004 Elsevier, Volume 1); van Oss, and Padovani, Cement manufacture and the environment, Part 2: Environmental challenges and opportunities, 2003 J. Ind. Ecol. 7: 93-126; van Oss and Padovani, Cement manufacture and the environment, Part 1: Chemistry and technology. 2002 J. Ind. Ecol. 6: 89-105; and Worrell, et al., Carbon dioxide emissions from the global cement industry, 2001 Ann. Rev. Energy Env. 26: 303-3029.

Indeed, every 1.0 t of OPC uses 1.50-1.75 t of minerals, 0.89-1.21 t of fuel, and 0.52-1.03 t of water for its production, and results in the emission of 0.70-0.92 t of carbon dioxide as well as various other toxic substances, including carbon monoxide, nitrogen oxides, sulfur oxides, hydrogen chloride, dioxins, lead, mercury and selenium. Since 72 million t of OPC are produced in the U.S. every year, this equates to the use of 108-126 million t of minerals, 64-87 million t of fuel, and 37-74 million t of water, and the emission of 50-66 million t of carbon dioxide.

In view of the poor environmental metrics of OPC, efforts have been made to produce “Green” and sustainable cements by partially or completely replacing OPC with alternative binders with lower ecological footprints, as described in the publications, Schneider et al., Sustainable cement production—present and future. 2011 Cement Concrete Res. 41: 642-650; Sharp, et al., Novel cement systems, 2010 Adv. Cem. Res. 22: 195-202; Damtoft et al., Sustainable development and climate change initiatives, 2008 Cement Concrete Res. 38: 115-127; Phair, Green chemistry for sustainable cement production and use. 2006 Green Chem. 8: 763-780; and Placet et al., Toward a Sustainable Cement Industry, pp 1-92 (2002 Battelle, Substudy 7).

With suitable formulation and additives, OPC can be partially or completely replaced by a variety of minerals and industrial byproducts, collectively referred to as Supplementary Cementitious Materials (SCMs, also known as Mineral Admixtures), the resultant products being referred to as blended cements and non-Portland cements respectively. Blended cements are described in the publications: Massazza, Pozzolana and pozzolanic cements, in Lea's Chemistry, of Cement and Concrete, pp. 471-631 (2003 Elsevier, 4th ed.); and Mineral Admixtures in Cement and Concrete, pp. 1-248 (2011 CRC Press); and Kosmatks et al., Portland, Blended, and Other Hydraulic Cements, in Design and Control of Concrete Mixtures, pp. 21-56 (2006 Portland Cement Association, 14th ed.).

SCMs are characterized as cementitious, pozzolanic (having cementitious activity in the presence of lime), or both cementitious and pozzolanic. ASTM C-989, C-618 and C-1240 describe three major classes of SCMS: (i) Iron blast furnace slags (cementitious); (ii) Fly ash Class C (cementitious and pozzolanic), fly ash Class F (pozzolanic), and natural (raw or calcined) pozzolans such as diatomaceous earths, opaline cherts and shales, tuffs, volcanic ashes, and calcined clays and shales; and (iii) Silica fume (pozzolanic). The major SCMs are low-value industrial byproducts, most notably fly ash and blast furnace slag, which are waste products of coal-fired power plants and iron ore smelters respectively. SCMs are described in Mineral Admixtures in Cement and Concrete, pp. 1-248 (2011 CRC Press); Supplementary Cementing Materials, pp. 1-283 (2011 Springer); Lohtia, et al., Mineral Admixtures, in Concrete Admixtures Handbook, pp. 657-739 (2006 Noyes, 2nd ed.); Waste Materials and Byproducts in Concrete, pp. 1-407 (2008 Springer), Kosmatks et al., Fly Ash, Slag, Silica Fume, and Natural Pozzolans, in Design and Control of Concrete Mixtures, pp. 57-72 (2006 Portland Cement Association, 14th ed.); Massazza, Pozzolana and pozzolanic cements, in Lea's Chemistry of Cement and Concrete, pp. 471-631 (2003 Elsevier, 4th ed.); and Waste Materials Used in Concrete Manufacturing, pp. 1-637 (1997 Noyes).

Since SCMs are industrial byproducts or lightly processed minerals, they have lower ecological footprints than OPC, as described by Schneider et al., Sustainable cement production—present and future, 2011 Cement Concrete Res. 41: 642-650; Sharp et al., Novel cement systems, 2010 Adv. Cem. res. 22: 195-202; Damtoft et al., Sustainable development and climate change initiatives, 2008 Cement Concrete Res. 38: 115-127; Phair, Green chemistry for sustainable cement production and use, 2006 Green Chem. 8: 763-780; and Placet et al., Toward a Sustainable Cement Industry, pp 1-92 (2002 Battelle, Substudy 7). For example, the CO₂ footprints of fly ash, blast furnace slag, steel slag, limestone fines and calcined natural pozzolans are 0.02-0.04, 0.13-0.16, 0.10-0.14, 0.16-0.19 and 0.18-0.22 t-CO₂ per t-SCM respectively, compared to OPC's CO₂ footprint of 0.70-0.92 t-CO₂ per t-cement. Substituting SCMs for OPC proportionally improves environmental metrics, with blended cements and non-Portland cements showing CO₂ footprints of only 0.28-0.67 and 0.26-0.50 t-CO₂ per t-cement respectively.

Blended cements, especially those employing fly ash and/or blast furnace slag as SCMs, are used worldwide in place of OPC for certain applications. In the U.S., blended cements are specified under ASTM C-595-06 as Portland-Pozzolan cement, Type IP(X), which allows 0-40% w/w replacement of OPC with a pozzolan (typically fly ash), and as Portland-blast furnace slag cement, Type IS(X), which allows 0-95% w/w replacement of OPC with blast furnace slag.

Blast furnace slag is a cementitious material that can replace up to 95% w/w of OPC in blended cements, and is typically used at 50% replacement level. But, its availability is limited, with U.S. and world production standing at 9 million and 250 million t respectively, or only 13 and 9% of OPC consumption respectively. Fly ash is available in much larger quantities, with U.S. and world production standing at 70 million and 700 million t, or on par with U.S. OPC consumption and some 25% of world OPC usage respectively. Its use in blended cements at low to moderate levels (0-50% replacement of OPC) can improve durability metrics such as ultimate compressive strength, permeability, salt resistance, rebar corrosion resistance, and freeze-thaw resistance. Fly ash is available at a low cost—in the range of $5-60 per t in the U.S., and in quantities large enough to satisfy the total demand for cement in the U.S. and some 25% of world cement demand.

Despite its availability and use potential, fly ash is highly underutilized with less than 15% of U.S. ash output going into blended cements, and with some 65% of ash sent for storage or disposal. This has resulted in the accumulation of over 500 million t of ash, a situation that seems certain to worsen as U.S. ash output is projected to increase to 100 million t by 2030. Unused ash carries significant public health and environmental burdens due to the presence of potentially toxic elements, and approaches for its safe and beneficial utilization in added value products such as cement are essential for the sustainable management of ash. Fly ash is reviewed in the publications, Ahmaruzzaman, A review on the utilization of fly ash, 2010 Prog. Energy Combust. Sci. 36: 327-363); Kelly et al., Coal Combustion Products Statistics, pp. 1-2 (2010 U.S. Geological Survey); Coal Combustion Product Production & Use Survey Results, pp. 1-2 (2009 American Coal Ash Association); Beneficial Use of Secondary Materials—Coal Combustion Products, pp. 1-95 (2008 U.S. Environmental Protection Agency); Nugteren, Fly ash: From waste to industrial product, 2007 Part. Part. Sys. Charact. 24: 49-55; Hall et al., Fly ash quality, past, present and future, and the effect of ash on the development of novel products, 2002 J. Chem. Technol. Biotechnol. 77: 234-239; and Rayzman, et al., Technology for chemical-metallurgical coal ash utilization, 1997 Energy Fuels 11: 761-773.

While fly ash is an attractive SCM, performance considerations limit the fly ash content in blended cements to less than 50% replacement of OPC, with U.S. states allowing a maximum substitution level in the range of just 15-25%. Despite the use of performance-enhancing chemical additives, the replacement of more than 25% of OPC with fly ash retards setting and the rate of hardness and compressive strength development, increases the demand for air-entraining agents, can adversely affect durability metrics such as salt resistance, and may require the use of increased cement content in cement compositions. For example, blended cements with 25% and 50% w/w replacement of OPC with fly ash typically show only 50-75% and 30-50% of the hardness and compressive strength development of OPC-based compositions, and can require 1-3 months to reach performance parity, as described in the publications, Mineral Admixtures in Cement and Concrete, pp. 1-248 (2011 CRC Press); Supplementary Cementing Materials, pp. 1-283 (2011 Springer); Lohtia et al., Mineral Admixtures, in Concrete Admixtures Handbook, pp. 657-739 (2006 Noyes, 2nd ed.); Waste Materials and Byproducts in Concrete, pp. 1-407 (2008 Springer), Kosmatks, et al., Fly Ash, Slag, Silica Fume, and Natural Pozzolans, in Design and Control of Concrete Mixtures, pp. 57-72 (2006 Portland Cement Association, 14th ed.); Massazza, Pozzolana and pozzolanic cements, in Lea's Chemistry of Cement and Concrete, pp. 471-631 (2003 Elsevier, 4th ed.); and Waste Materials Used in Concrete Manufacturing, pp. 1-637 (1997 Noyes).

Attempts to develop blended cements containing other SCMs such as limestone, steel slag and non-ferrous slags, have been hampered by similar albeit worse problems to OPC-fly ash cements. Thus, ASTM C-150 allows the addition of only 5% of limestone to OPC, due to concerns about setting retardation, poor strength development and excessive shrinkage at higher limestone contents. Blended cements made with steel slag and non-ferrous slags face a variety of problems including poor setting, slow hardness and strength development, delayed expansion, cracking, and poor freeze-thaw resistance.

Performance issues and the lack of industry-standard specifications for high-SCM content blended cements necessitate extensive pretesting to ensure durable cement compositions that meet building codes, and invariably lead to higher costs. As such, the availability and use of blended cements in the U.S. has been highly restricted, with the average replacement level of SCMs for OPC being less than 15%, and less than 3% of cement in the U.S. being blended cement. See e.g. Loreti, Greenhouse Gas Emission Reductions from Blended Cement Production, pp. 1-35 (2008 The Loreti Group); and Characteristics of Portland and Blended Cements: Results of a Survey of Manufacturers, pp. 83-101 (2006 IEEE Conference Proceedings).

Non-Portland cements, such as those based upon fly ash and/or blast furnace slag suffer from similar albeit worse problems to blended cements. For example, cements made from fly ash, or blends of fly ash with other SCMs, can display flash or delayed setting, poor hardness and compressive strength development, excessive shrinkage, aggregate-induced expansion, and poor long-term durability. Indeed, there is no industry-standard specification for non-Portland cements in the U.S., and no significant commercial production of such cements.

Various approaches have been used to elevate the performance of blended cements and non-Portland cements to that of OPC, the most successful being the use of chemical admixtures to improve such properties as setting, and the rate of hardness and compressive strength development. As generally described in the publications, Chemical Admixtures for Concrete, pp. 1-1 to 6-10 (1999 Taylor and Francis, 3rd ed.) and Concrete Admixtures Handbook, pp. 137-1024 (1996 Noyes, 2nd ed.), chemical admixtures are inorganic or organic compounds that are used to modify the physicochemical properties of cement compositions. These properties include viscosity, slump, water requirement, setting, hardness, compressive strength, shrinkage, porosity, air content, water resistance, freeze-thaw resistance, salt resistance and rebar corrosion resistance. Chemical admixtures such as sodium hydroxide, sodium silicate, sodium aluminate, sodium citrate, calcium chloride, calcium sulfate, calcium nitrate, calcium nitrite, calcium formate, citric acid, carboxylic acid-containing polymers and copolymers, and alkanolamines have long been used to regulate setting and hardness and compressive strength development in OPC, and have found similar albeit less utility in blended cements and non-Portland cements.

The prior art describes the application of calcium salts, citric acid, and citrate salts as accelerators for high-SCM content blended cements and SCM-based non-OPC cements. However, these approaches are often not placement/use equivalent to OPC, and give variable results in terms of setting, hardness and strength development, shrinkage, cracking, aggregate reactivity and/or long-term durability. Because of these issues, none of these approaches have found significant commercial applications, other than very specialized uses such as rapid-setting cements. The use of citric acid and citrate salts as accelerator(s) for blended cements and fly ash-based non-Portland cements is described U.S. Pat. No. 4,842,649, U.S. Pat. No. 4,997,484, U.S. Pat. No. 5,374,308, U.S. Pat. No. 5,536,310, U.S. Pat. No. 4,640,715, U.S. Pat. No. 4,642,137, U.S. Pat. No. 7,854,803, U.S. Pat. No. 7,288,148, U.S. Patent Application 2008178770A1 and U.S. Pat. No. 6,827,776. The use of calcium sulfate as accelerator for fly ash-based non-Portland cements is described in the publications, U.S. Pat. No. 5,439,518, U.S. Pat. No. 5,578,122, U.S. Pat. No. 4,240,952, U.S. Pat. No. 4,470,850 and U.S. Pat. No. 4,256,504. The use of calcium nitrate as an accelerator for blended cements is described in the publication, U.S. Patent Application 20110048285 A1.

The prior art also describes the use of highly alkaline chemical admixtures (also known as alkali activators) such as sodium hydroxide, potassium hydroxide, sodium silicate and sodium aluminate for forming so-called “geopolymers” with blended cements and SCM-based non-Portland cements. While the properties of geopolymer cements can match or exceed those of OPC or conventional blended cements, they have severe drawbacks—most notably that the admixtures are highly corrosive and required in large amounts (typically 5-25% of the cement content), that the cements are not use/placement equivalent to OPC and require special formulation, handling and curing, and that they lack long-term stability and durability. Indeed, there is currently no geopolymeric cement of commercial significance in the U.S. Alkali activators and geopolymer cements are described in the publications, Alkali Activated Cements and Concretes, pp. 1-334 (2006 Taylor and Francis); Duxson et al., The role of inorganic polymer technology in the development of ‘green concrete’, 2007 Cement Concrete Res. 37: 1590-1597; Pachecho-Torgal et al., Alkali-activated binders: A review Part 1. Historical background, terminology, reaction mechanisms and hydration products, 2008 Constr. Build. Mater. 22: 1305-1314; Pachecho-Torgal et al., Alkali-activated binders: A review. Part 2. About materials and binders manufacture, 2008 Constr. Build. Mater. 22: 1315-1322; and Duxson et al., Geopolymer technology: the current state of the art, 2007 J. Mater. Sci. 42: 2917-2933.

While currently available chemical admixtures are useful for improving the properties of blended cements containing low to moderate levels of SCMs (up to 25% of fly ash, up to 50% of blast furnace slag, and up to 15% of limestone), their performance is not as satisfactory with higher levels of SCMs, and even less so with SCM-based non-Portland cements. To date there is no commercial general-use high-SCM content blended cement or non-Portland cement available in the U.S., despite the demand for such Green and sustainable cements as alternatives to OPC.

SUMMARY OF THE INVENTION

Thus, there is a need in the art for chemical admixtures that can improve the properties of blended cements containing high levels of SCMs and SCM-based non-Portland cements, and that can make them use/performance equivalent to OPC. In particular, there is a need for admixtures capable of improving setting, the rate of hardness and compressive strength development, shrinkage, permeability, and long-term durability indicators such as salt resistance and freeze-thaw resistance. Such admixtures would improve economics by enabling the partial or complete substitution of OPC, which costs 580-100 per t, with SCMs, which cost just $5-60 per t. Also, environmental and public health metrics would be greatly improved by reducing the natural resource use and pollution footprint deriving from OPC, and by increasing the beneficial use of SCMs and diverting them from storage and disposal.

It is an object of an embodiment this invention to provide a new class of chemical admixtures that improves the properties of cement compositions, particularly with regard to blended cements and non-Portland cements made with SCMs.

Accordingly, an embodiment of the present invention is directed to a new class of chemical admixtures for hydraulic cement compositions such as pastes, mortars, grouts and concretes. The cement compositions are comprised of Portland cement, or blended cements or non-Portland cements made with Supplementary Cementitious Materials (SCMs). The admixtures improve the properties of cement compositions, including setting, hardness, compressive strength, shrinkage and freeze-thaw resistance, thereby substantially obviating one or more of the problems due to limitations and disadvantages of the related art.

An object of the present invention is to provide an economical admixture that can be used to prepare hydraulic cement compositions that are cheaper, more environmentally friendly, and have a lower carbon footprint than traditional cement composition. Another object of the present invention is to enable Portland cement to be partially or completely replaced by SCMs in hydraulic cement compositions, while maintaining substantial use and performance equivalence.

The present invention provides the processes and methods for preparing the admixtures, and further provides methods in which they can be used in the manufacture of hydraulic cement compositions such as pastes, mortars, grouts and concretes. Additional features and advantages of the invention will be set forth in the descriptions that follow and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structures and compositions particularly pointed out in the written description and claims thereof.

To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, an embodiment of the present invention provides admixtures for hydraulic cement compositions, which contain complexes of metals and/or semi-metals with hydroxycarboxylic acid-derived ligands, and may be described by the following general empirical chemical formula:

A¹_a . . . Aⁿ_xB¹_a′ . . . Bⁿ_x′[M¹_a″ . . . Mⁿ_x″C¹_a′″ . . . Cⁿ_x′″L¹_a″″ . . . Lⁿ_x″″]  Formula 1.

wherein, A¹ . . . Aⁿ are cations; B¹_a′ . . . Bⁿ_x′ are anions; M¹ . . . Mⁿ are chelated metal and/or semi-metal cations; C¹ . . . Cⁿ are coordinating ligands; and L¹ . . . Lⁿ are chelating hydroxycarboxylic acid-derived ligands. The subscripts a and x; a′ and x′; a″ and x″; a′″ and x′″ and a″″ and x″″ refer to the cation, anion, chelated metal, coordinating ligand, and chelating hydroxycarboxylic acid-derived ligand stoichiometries respectively. The admixtures described by the above general formula contain at least one chelated metal or semi-metal cation (Mⁿ_x″), and at least one chelating hydroxycarboxylic acid-derived ligand (Lⁿ_x″″). Furthermore, the admixtures may contain one or more cations (Aⁿ_x), and/or one or more anions (Bⁿ_x′) and/or one or more coordinating ligands (Cⁿ_x′″).

Additional aspects and embodiments of the invention will be provided, without limitation, in the detailed description of the invention that is set forth below.

DETAILED DESCRIPTION OF THE INVENTION

Set forth below is a description of what are currently believed to be preferred embodiments of the claimed invention. Any alternates or modifications in function, purpose, or structure are intended to be covered by the claims of this application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. The terms “comprises” and/or “comprising,” as used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

The term “cement composition” as used herein refers to pastes, mortars and concretes. The cement compositions are comprised of Portland cement, or blended or non-Portland cements made with Supplementary Cementitious Materials (SCMs).

The admixtures contain complexes of metals and/or semi-metals with hydroxycarboxylic acid-derived ligands, and may be described by the following general empirical chemical formula:

A¹_a . . . Aⁿ_xB¹_a′ . . . Bⁿ_x′[M¹_a″ . . . Mⁿ_x″C¹_a′″ . . . Cⁿ_x′″L¹_a″″ . . . Lⁿ_x″″]  Formula 1.

In the above general formula, A¹ . . . Aⁿ are cations; B¹_a′ . . . Bⁿ_x′ are anions: M¹ . . . Mⁿ are chelated metal and/or semi-metal cations; C¹ . . . Cⁿ are coordinating ligands; and L¹ . . . Lⁿ are chelating hydroxycarboxylic acid-derived ligands. The subscripts a and x; a′ and x′; a″ and x″; a′″ and x′″; and a″″ and x″″ refer to the cation, anion, chelated metal, coordinating ligand, and chelating hydroxycarboxylic acid-derived ligand stoichiometries respectively. The admixtures, described by the above general formula, contain at least one chelated metal or semi-metal cation (Mⁿ_x″), and at least one chelating hydroxycarboxylic acid-derived ligand (Lⁿ_x″″). Furthermore, the admixtures may contain one or more cations (Aⁿ_x), and/or one or more anions (Bⁿ_x′) and/or one or more coordinating ligands (Cⁿ_x′″).

The cations (A¹_a . . . Aⁿ_x) in Formula 1 are in particular selected from, but not limited to the examples detailed below and depicted in Table 1 (structures in Table 1 that correspond to the listed examples are identified parenthetically):

(i) The ammonium ion (NH₄+), and alkyl-, cycloalkyl-, aryl-, arylalkyl and/or heteroaryl-substituted ammonium ions (1-4), as exemplified by but not limited to the tetramethylammonium, ethyltrimethylammonium, butyltrimethylammonium, cyclohexylammonium, dicyclohexylammonium, and benzyltrimethylammoniun ions.

(ii) Cations of alkyl-, cycloalkyl-, aryl-, and/or arylalkyl- and/or heteroaryl-substituted aminoalcohols, as exemplified but not limited to the 2-hydroxyethylammonium, bis(2-hydroxyethyl)ammonium, and tris(2-hydroxyethyl)ammonium ions (5-7).

(iii) The proton (H⁺), and metal cations, as exemplified by but not limited to ions of the lithium family (Group IA, 8), and beryllium family (Group IIA, 9).

TABLE 1

Examples of Cations (Aⁿ_x)

1

2

3

4

R^1,3,5,7 = alkylene/heteroalkylene (C_0-18N_0-6O_0-6),

cycloalkylene/cycloheteroalkylene (C_3-8N_0-3O_0-3), arylene/heteroalkylene

(C_3-14N_0-3); R^2,4,6,8 = H, alkyl/heteroalkyl (C_0-18N_1-6O_0-6),

cycloalkyl/cycloheteroalkyl (C_3-8N_1-3O_0-3), aryl/heteroaryl (C_3-14N_1-3).

5

6

7

R^1,3,5 = alkylene/heteroalkylene (C_0-18N_0-6O_0-6),

cycloalkylene/cycloheteroalkylene (C_3-8N_0-3O_0-3), arylene/heteroalkylene

(C_3-14N_0-3); R^2,4,6 = H, alkyl/heteroalkyl (C_0-18N_1-6O_0-6),

cycloalkyl/cycloheteroalkyl (C_3-8N_1-3O_0-3), aryl/heteroaryl (C_3-14N_1-3).

H⁺ Li⁺ Na⁺ K⁺ Rb⁺ Cs⁺

8

Be²⁺ Mg²⁺ Ca²⁺ Sr²⁺ Ba²⁺

9

The anions (B¹_a . . . Bⁿ_x) in Formula 1 are in particular selected from, but not limited to the examples detailed below and depicted in Table 2 (structures in Table 2 that correspond to the listed examples are identified parenthetically):

(i) Metal, non-metal, and semi-metal anions, as exemplified by but not limited to ions of the boron family (Group IIIA, 10), carbon family (Group IVA, 11), nitrogen family (Group VA, 12), oxygen family (Group VIA, 13) and fluorine family (Group VIIA, 14), and derivatives thereof (15).

(ii) The anions of aliphatic, cycloaliphatic, aromatic arylaliphatic and heteroaromatic sulfonic acids (16), as exemplified by, but not limited to methanesulfonic acid, ethanesulfonic acid, propane-1-sulfonic acid, butane-1-sulfonic acid, cyclohexanesulfonic acid, benzenesulfonic acid, 4-methylbenzenesulfonic acid (tosic acid), and pyridine-3-sulfonic acid.

(iii) The anions of aliphatic, cycloaliphatic, aromatic arylaliphatic and heteroaromatic sulfate monoesters (17), as exemplified by, but not limited to prop-1-yl sulfate, but-1-yl sulfate, hex-1-yl sulfate, dec-1-yl sulfate, dodec-1-yl sulfate (lauryl sulfate), tetradec-1-yl sulfate (myristyl sulfate), hexadec-1-yl sulfate (palmityl sulfate), octadec-1-yl sulfate (stearyl sulfate), and phenylmethyl sulfate (benzyl sulfate).

(iv) The anions of aliphatic, heteroaliphatic, cycloaliphatic, cycloheteroaliphatic, aromatic, arylaliphatic and heteroaromatic monocarboxylic acids (18), as exemplified by, but not limited to ethanoic acid (acetic acid), propanoic acid (propionic acid), butanoic acid (butyric acid), pentanoic acid (valeric acid), hexanoic acid (caproic acid), heptanoic acid (ananthic acid), heptanoic acid (caprylic acid), octanoic acid (pelargonic acid), decanoic acid (capric acid), dodecanoic acid (lauric acid), tetradecanoic acid (myristic acid), hexadecanoic acid (palmitic acid), octadecanoic acid (stearic acid), 2-methylpropanoic acid (isobutyric acid). 2-ethylhaxanoic acid (octoic acid), 2-methyloctadecanoic acid (2-methylstearic acid), ethoxyethanoic acid (ethoxyacetic acid), (2′-ethoxyethoxy)ethanoic acid, cyclopentane carboxylic acid, cyclohexane carboxylic acid, benzoic acid, 4-methylbenzenecarboxylic acid (p-toluic acid), napthalene1-carboxylic acid (1-napthoic acid), phenylacetic acid, 3-phenylpronanoic acid, and pyridine-2-carboxylic acid (2-picolinic acid).

TABLE 2

Examples of Anions (Bⁿ_x′)

BO₂⁻ BO₃³⁻ B₂O₅⁴⁻ B₃O₇⁵⁻ B₄O₇²⁻ B₄O₉⁶⁻

10

CO₃²⁻ HCO₃⁻ SiO₃²⁻ SiO₂(OH)₂²⁻ SiO₄⁴⁻

11

NO₂⁻ NO₃⁻ NPO₃²⁻ PO₃³⁻ HPO₄²⁻ PO₄³⁻ P₆O₁₈⁶⁻

12

OH⁻ S²⁻ SO₃²⁻ SO₄²⁻ S₂O₃²⁻ S₄O₆²⁻

13

F⁻ Cl⁻ Br⁻ I⁻ ClO₃⁻

14

TiF₆²⁻ BF₄⁻ AlF₆³⁻ SiF₆²⁻ PFO₃²⁻ PF₂O₂⁻ PF₆⁻ SFO₃⁻

15

16

17

18

R¹ = alkylene/heteroalkylene (C_0-18N_0-6O_0-6),

cycloalkylene/cycloheteroalkylene (C_3-8N_0-3O_0-3), arylene/heteroalkylene

(C_3-14N_0-3); R^2,3 = H, alkyl/heteroalkyl (C_0-18N_1-6O_0-6),

cycloalkyl/cycloheteroalkyl (C_3-8N_1-3O_0-3), aryl/heteroaryl (C_3-14N_1-3).

The chelated metal/semi-metal cations (M¹_a″ . . . Mⁿ_x″) in Formula 1 are in particular selected from, but not limited to the examples detailed below and depicted in Table 3 (structures in Table 3 that correspond to the listed examples are identified parenthetically):

(i) Metal and/or semi-metal cations, as exemplified by but not limited to ions of the beryllium family (Group IIA, 19), scandium family (Group IIIB, 20), titanium family (Group IVB, 21), vanadium family (Group VB, 22), chromium family (Group VIB, 23), manganese, iron, cobalt, nickel, copper and zinc families (Groups IB, IIB, VIIB and VIIIB, 24), boron family (Group IIIA, 25), carbon family (Group IVA, 26), and nitrogen family (Group VA, 27).

(ii) Oxocations, as exemplified by but not limited to oxocations and peroxocations of the titanium family (Group IVB, 28), vanadium family (Group VB, 29), chromium family (Group VIB, 30), and nitrogen family (Group VA, 31).

TABLE 3

Examples of Metal Cations (Mⁿ_x″) Chelating Hydroxycarboxylic Acid-Derived Ligands

Be²⁺ Mg²⁺ Ca²⁺ Sr²⁺ Ba²⁺

Sc³⁺ Y³⁺ La³⁺ Ce³⁺ Ce⁴⁺ Eu³⁺

Ti⁴⁺ Zr⁴⁺ Hf⁴⁺

19

20

21

V³⁺ V⁴⁺ V⁵⁺ Nb³⁺ Nb⁴⁺ Nb⁵⁺

Cr³⁺ Mo⁴⁺ Mo⁶⁺ W⁶⁺

Mn²⁺ Fe²⁺ Fe³⁺ Co²⁺ Ni²⁺ Cu²⁺

Ta³⁺ Ta⁴⁺ Ta⁵⁺

Zn²⁺

22

23

24

B³⁺ Al³⁺ Ga³⁺ In³⁺

Ge⁴⁺ Sn²⁺ Sn⁴⁺

Sb³⁺ Sb⁵⁺ Bi³⁺

TiO²⁺ [Ti₂(O₂)₂]⁴⁺

[Ti₄(O₂)₄]⁸⁺ ZrO²⁺

HfO²⁺

25

26

27

28

VO³⁺ VO₂⁺ NbO³⁺ TaO³⁺

MoO⁴⁺ MoO³⁺ MoO₂⁺

SbO⁺ BiO⁺

TaO₂⁺

WO⁴⁺ WO₂²⁺ WO³⁺ WO₂⁺

29

30

31

The coordinating ligands (C¹_a′″ . . . Cⁿ_x′″) in Formula 1 are in particular selected from, but not limited to the examples detailed below and depicted in Table 4 (structures in Table 4 that correspond to the listed examples are identified parenthetically):

(i) Water (H₂O).

(ii) The anions of aliphatic, heteroaliphatic, cycloaliphatic, cycloheteroaliphatic, aromatic, arylaliphatic and heteroaromatic monocarboxylic acids (32), as exemplified by, but not limited to ethanoic acid (acetic acid), propanoic acid (propionic acid), butanoic acid (butyric acid), pentanoic acid (valeric acid), hexanoic acid (caproic acid), heptanoic acid (ananthic acid), heptanoic acid (caprylic acid), octanoic acid (pelargonic acid), decanoic acid (capric acid), dodecanoic acid (lauric acid), tetradecanoic acid (myristic acid), hexadecanoic acid (palmitic acid), octadecanoic acid (stearic acid), 2-methylpropanoic acid (isobutyric acid), 2-ethylhaxanoic acid (octoic acid), 2-methyloctadecanoic acid (2-methylstearic acid), ethoxyethanoic acid (ethoxyacetic acid), (2′-ethoxyethoxy)ethanoic acid, cyclopentane carboxylic acid, cyclohexane carboxylic acid, furan-2-carboxylic acid (2-furoic acid), benzoic acid, 4-methylbenzenecarboxylic acid (p-toluic acid), napthalene 1-carboxylic acid (1-napthoic acid), phenylacetic acid, 3-phenylpronanoic acid, and pyridine-2-carboxylic acid (2-picolinic acid).

(iii) The anions of aliphatic, heteroaliphatic, cycloaliphatic, cycloheteroaliphatic, aromatic, arylaliphatic and heteroaromatic dicarboxylic acids (33), as exemplified by but not limited to ethanedioic acid (oxalic acid), propane-1,3-dioic acid (malonic acid), butane-1,4-dioic acid (succinic acid), pentane-1,5-dioic acid (glutaric acid), hexane-1,6-dioic acid (adipic acid), heptane-1,7-dioic acid (pimelic acid), octane-1,8-dioic acid (suberic acid), nonane-1,9-dioic acid (azealic acid), decane-1,10-dioic acid (sebacic acid), dodecane-1,12-dioic acid, tetradecane-1,14-dioic acid, hexadecane-1,16-dioic acid, octadecane-1,18-dioic acid, cyclohexane-1,2-dicarboxylic acid, furan-2,5-dicarboxylic acid, benzene-1,2-dicarboxylic acid (phthalic acid), benzene-1,3-dicarboxylic acid (isophthalic acid), and benzene-1,4-dicarboxylic acid (terephthalic acid).

(iv) The anions of aliphatic, heteroaliphatic, cycloaliphatic, cycloheteroaliphatic, aromatic, arylaliphatic and heteroaromatic tricarboxylic acids (34), as exemplified by but not limited to 3-carboxypentane-1,5-dioic acid (carballylic acid), benzene-1,2,4-tricarboxylic acid (trimellitic acid), and benzene-1,3,5-tricarboxylic acid (trimesic acid).

(v) The anions of alkyl, heteroalkyl, cycloalkyl, cycloheteroalkyl, aryl, arylalkyl and heteroaryl-substituted unsaturated aliphatic monocarboxylic acids (35), as exemplified by but not limited to (E)-but-2-enoic acid (crotonic acid), (E)-2-methylbut-2-enoic acid (tiglic acid), and (E)-3-phenylprop-2-enoic acid (cinnamic acid).

(vi) The anions of alkyl, heteroalkyl, cycloalkyl, cycloheteroalkyl, aryl, arylalkyl and heteroaryl-substituted unsaturated aliphatic dicarboxylic acids (36), as exemplified by but not limited to (Z)-but-2-ene-1,4-dioic acid (maleic acid), and (E)-but-2-ene-1,4-dioic acid (fumaric acid).

(vii) The anions of aliphatic, aromatic or mixed aliphatic-aromatic polycarboxylic acids, polycarboxylic acid copolymers and their derivatives, as exemplified by but not limited to poly(acrylic acid), poly(methacrylic acid), poly(itaconic acid), poly(maleic acid), poly(acrylic acid-co-maleic acid), poly(ethylene-co-acrylic acid), poly(ethylene-co-methacrylic acid), poly(ethylene-co-maleic acid), poly(styrene-co-maleic acid), poly(methyl vinyl ether-alt-maleic acid), poly(acrylic acid)-poly(ethylene glycol) methyl ether esters, and poly(methacrylic acid)-poly(propylene glycol) methyl ether esters.

(viii) Aliphatic, heteroaliphatic, cycloaliphatic, cycloheteroaliphatic, aromatic, arylaliphatic and heteroaromatic diols (37), triols, and polyols, as exemplified by but not limited to ethane-1,2-diol (ethylene glycol), propane-1,2-diol, propane-1,3-diol, butane-1,2-diol, butane-1,3-diol, butane-2,3-diol, butane-1,4-diol, benzene-1,2-diol (catechol), benzene-1,3-diol (resorcinol), 4-methylbenzene-1,2-diol (4-methylcatechol), propane-1,2,3-triol (glycerol), butane-1,2,4-triol, hexane-1,2,6-triol, benzene-1,2,3-triol (pyrogallol), benzene-1,2,4-triol (hydroxyhydroquinone), benzene-1,3,5-triol (phloroglucinol), hexane-1,2,3,4,5,6-hexaol (sorbitol), 2-(2′-hydroxyethoxy)ethanol (diethylene glycol), and 2-[2′-(2″-hydroxyethoxy)ethoxy]ethanol (triethylene glycol).

(ix) Aliphatic, heteroaliphatic, cycloaliphatic, cycloheteroaliphatic, aromatic, arylaliphatic and heteroaromatic hydroxynitriles (38), as exemplified by but not limited to 3-hydroxypropanenitrile, 3-hydroxybutanenitrile, 4-hydroxybutanenitrile, and 5-hydroxypentanenitrile.

(x) Aliphatic, heteroaliphatic, cycloaliphatic, cycloheteroaliphatic, aromatic, arylaliphatic and heteroaromatic diamines (39), as exemplified by but not limited to ethane-1,2-diamine (ethylene diamine), propane-1,2-diamine, propane-1,3-diamine, butane-1,4-diamine, xexane-1,6-diamine, and cyclohexane-1,2-diamine.

(xi) Aliphatic, heteroaliphatic, cycloaliphatic, cycloheteroaliphatic, aromatic, arylaliphatic and heteroaromatic aminonitriles (40), as exemplified but not limited to 3-aminopropanenitrile, 3-aminopentanenitrile, 5-aminopentanenitrile, and 6-aminohexanenitrile.

(xii) Aliphatic, heteroaliphatic, cycloaliphatic, cycloheteroaliphatic, aromatic, arylaliphatic and heteroaromatic aminoalcohols (41-43), as exemplified by but not limited to 2-aminoethanol (ethanolamine), 2-aminopropan-1-ol, 2-aminobutan-1-ol, 4-aminobutan-1-ol, bis(2-hydroxyethyl)amine(diethanolamine), tris(2-hydroxyethyl)amine(triethanolamine), 2-(2′-aminoethoxy)ethanol (diethylene glycol amine), 2-aminophenol, and 3-aminophenol.

TABLE 4

Examples of Coordinating Ligands (Cⁿ_x′′′)

32

33

34

R^1,6 = alkylene/heteroalkylene (C_0-18N_0-6O_0-6),

cycloalkylene/cycloheteroalkylene (C_3-8N_0-3O_0-3),

arylene/heteroalkylene (C_3-14N_0-3); R^2,3,4,5 = H, alkyl/heteroalkyl

(C_0-18N_1-6O_0-6), cycloalkyl/cycloheteroalkyl (C_3-8N_1-3O_0-3),

aryl/heteroaryl (C_3-14N_1-3).

35

36

37

R^1,6 = alkylene/heteroalkylene (C_0-18N_0-6O_0-6),

cycloalkylene/cycloheteroalkylene (C_3-8N_0-3O_0-3),

arylene/heteroalkylene (C_3-14N_0-3); R^2,3,4,5 = H, alkyl/heteroalkyl

(C_0-18N_1-6O_0-6), cycloalkyl/cycloheteroalkyl (C_3-8N_1-3O_0-3),

aryl/heteroaryl (C_3-14N_1-3).

38

39

40

R¹ = alkylene/heteroalkylene (C_0-18N_0-6O_0-6),

cycloalkylene/cycloheteroalkylene (C_3-8N_0-3O_0-3),

arylene/heteroalkylene (C_3-14N_0-3); R^2,3 = H, alkyl/heteroalkyl

(C_0-18N_1-6O_0-6), cycloalkyl/cycloheteroalkyl (C_3-8N_1-3O_0-3),

aryl/heteroaryl (C_3-14N_1-3).

41

42

43

R^1,3,5 = alkylene/heteroalkylene (C_0-18N_0-6O_0-6),

cycloalkylene/cycloheteroalkylene (C_3-8N_0-3O_0-3),

arylene/heteroalkylene (C_3-14N_0-3); R^2,4,6 = H, alkyl/heteroalkyl

(C_0-18N_1-6O_0-6), cycloalkyl/cycloheteroalkyl (C_3-8N_1-3O_0-3),

aryl/heteroaryl (C_3-14N_1-3).

The chelating hydroxycarboxylic acid-derived ligands L¹_a″″L²_b″″ . . . Lⁿ_x″″ are selected from, but not limited to the examples detailed below and depicted in Tables 5-7 (structures in Tables 5-7 that correspond to the listed examples are identified parenthetically):

(i) Anions of aliphatic hydroxycarboxylic acids with a single hydroxyl group and a single carboxyl group, as exemplified by but not restricted to hydroxyacetic acid (glycolic acid, 45), 3-hydroxypropanoic acid (46), 2-hydroxypropanoic acid (lactic acid, 47), 4-hydroxybutanoic acid (4-hydroxybutyric acid, 48), 3-hydroxybutanoic acid (3-hydroxybutyric acid, 49), 2-hydroxybutanoic acid (2-hydroxybutyric acid, 50), 3-hydroxy-2-methylpropanoic acid (3-hydroxyisobutyric acid, 51), 2-hydroxypentanoic acid (52), 3-hydroxypentanoic acid (53), and 3-hydroxy-3-methylbutanoic acid (54).

(ii) Anions of aliphatic hydroxycarboxylic acids with two or more hydroxyl and/or carboxyl groups, as exemplified by but not restricted to 2-hydroxypropane-1,3-dioic acid (tartronic acid, 55), 2-hydroxybutane-1,4-dioic acid (malic acid, 56), 2-hydroxypentane-1,5-dioic acid (57), 2-hydroxy-2-methylbutane-1,4-dioic acid (citramalic acid, 58), 3-carboxy-3-hydroxypentane-1,5-dioic acid (citric acid, 59), 3-carboxy-3-hydroxyhexane-1,6-dioic acid (homocitric acid, 60), 2,3-dihydroxypropanoic acid (glyceric acid, 61), 3,5-dihydroxy-3-methylpentanoic acid (mevalonic acid, 62), 2,3-dihydroxybutane-1,4-dioic acid (tartaric acid, 63), 2,3,4-trihydroxybutanoic acid (threonic acid, 64), 2,3,4,5,6-pentahydroxyhexanoic acid (gluconic acid, 65), and 2,3,4,5-tetrahydroxyhexane-1,6-dioic acid (mucic acid, 66).

(iii) Anions of cycloaliphatic hydroxycarboxylic acids, as exemplified by but not restricted to 1,3,4,5-tetrahydroxycyclohex-1-carboxylic acid (quinic acid, 67), and 3,4,5-trihydroxycyclohex-1-ene-1-carboxylic acid (shikimic acid, 68).

(iv) Anions of functionalized aliphatic or cycloaliphatic hydroxycarboxylic acids, as exemplified by but not restricted to 2-(2′-hydroxyethoxy)butane-1,4-dioic acid (hydroxyethylsuccinic acid, 69), 3-hydroxy-2-oxo-propanoic acid (hydroxypyruvic acid, 70), N,N-bis(2′-hydroxyethyl)-aminoethanoic acid (Bicine, 71), 2-amino-3-hydroxypropanoic acid (serine, 72), 2-amino-3-hydroxybutanoic acid (threonine, 73), 3-amino-4-hydroxybutanoic acid (homoserine, 74), 2-amino-4-hydroxybutanoic acid (□-homoserine, 75), 4-hydroxypyrrolidine-2-carboxylic acid (4-hydroxyproline, 76), and 3-hydroxypyrrolidine-2-carboxylic acid (3-hydroxyproline, 77).

TABLE 5

Examples of Chelating Hydroxycarboxylic Acid Ligands

44

X = H or OH; Y = H or CO₂H; R^{1,2,3,4,5,6,7,8,9} = alkylene/heteroalkylene

(C_1-18N_0-6O_0-6), cycloalkylene/cycloheteroalkylene (C_3-8N_0-3O_0-3),

arylene/heteroalkylene (C_3-14N_0-3); R^10,11 = H, alkyl/heteroalkyl

(C_0-18N_1-6O_0-6), cycloalkyl/cycloheteroalkyl (C_3-8N_1-3O_0-3),

aryl/heteroaryl (C_3-14N_1-3).

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

(v) Anions of aryalkylhydroxycarboxylic acids, as exemplified by but not restricted to 3-hydroxy-2-phenylpropanoic acid (tropic acid, 78), 2-hydroxy-2-phenylethanoic acid (mandelic acid, 79), and 2-hydroxy-2-(3′,4′-dihydroxyphenyl)ethanoic acid (3,4-dihydroxymandelic acid, 80).

(vi) Anions of aromatic hydroxycarboxylic acids, exemplified by but not restricted to 2-hydroxybenzoic acid (salicylic acid, 81), 2,3-dihydroxybenzoic acid (3-hydroxysalicylic acid, 82), 2,4-dihydroxybenzoic acid (4-hydroxysalicylic acid, 83), 2,5-dihydroxybenzoic acid (5-hydroxysalicylic acid, 84), 2,6-dihydroxybenzoic acid (6-hydroxysalicylic acid, 85), 3,4,5-trihydroxybenzoic acid (gallic acid, 86), 4-hydroxy-3-methoxybenzoic acid (vanillic acid, 87), 3-hydroxybenzene-1,2-dicarboxylic acid (3-hydroxyphthalic acid, 88), and 4-hydroxybenzene-1,2-dicarboxylic acid (4-hydroxyphthalic acid, 89).

(vii) Anions of aryalkenylhydroxycarboxylic acids, as exemplified by but not restricted to 3-(2′-hydroxyphenyl)prop-2-enoic acid (o-coumaric acid, 90), 3-(3′-hydroxyphenyl)prop-2-enoic acid m-coumaric acid, 91), 3-(4′-hydroxyphenyl)prop-2-enoic acid (p-coumaric acid, 92), 3-(3′,4′-dihydroxyphenyl)prop-2-enoic acid (caffeic acid, 93), and 3-(3′-methoxy-4′-hydroxyphenyl)prop-2-enoic acid (ferulic acid, 94).

(viii) Anions of functional arylhydroxycarboxylic acids, as exemplified by but not restricted to 2-amino-2-(4′-hydroxyphenyl)ethanoic acid (hydroxyphenylglycine, 95), and 2-amino-3-(3′,4′-dihydroxyphenyl)propanoic acid (dihydroxyphenylalanine, DOPA, 96).

(ix) Anions of heterocyclic hydroxycarboxylic acids, as exemplified by but not restricted to 3-hydroxypyridine-2-carboxylic acid (3-hydroxypicolinic acid, 97), 4-hydroxypyridine-2-carboxylic acid (4-hydroxypicolinic acid, 98), 6-hydroxypyridine-2-carboxylic acid (6-hydroxypicolinic acid, 99), 2-hydroxypyridine-5-carboxylic acid (6-hydroxynicotinic acid, 100), 2-hydroxypyridine-3-carboxylic acid (2-hydroxynicotinic acid, 101), 3-hydroxypyridine-4-carboxylic acid (3-hydroxyisonicotinic acid, 102), and 2-hydroxyquinoline-4-carboxylic acid (103).

(x) Anions of conjugates of aliphatic and aromatic hydroxycarboxylic acids, as exemplified by but not restricted to chlorogenic acid (104).

TABLE 6

Further Examples of Chelating Hydroxycarboxylic Acid Ligands

78

79

80

81

82

83

84

85

86

87

88

89

90

91

92

93

94

95

96

97

98

99

100

101

102

103

104

(xi) Anions of derivatives of the hydroxycarboxylic acids detailed above, including but not limited to esters, thioesters, amides, N-substituted amides, imides, acylhydrazines, and hydroxamic acids, as exemplified by but not limited to 2-O-esters (105 and 106) of 2,3-dihydroxybutane-1,4-dioc (63) acid with monocarboxylic acids and dicarboxylic acids, and monoesters, diesters, monoamides and diamides (107-110) of 3-carboxy-3-hydroxypentane-1,5-dioic acid (citric acid, 59).

TABLE 7

Examples of Chelating Hydroxycarboxylic Acid Derivative Ligands (Cⁿ_x′′′)

105

106

107

X = N or O; R¹ = alkylene/heteroalkylene (C_0-18N_0-6O_0-6),

cycloalkylene/cycloheteroalkylene (C_3-8N_0-3O_0-3), arylene/heteroalkylene

(C_3-14N_0-3); R^2,3 = H, alkyl/heteroalkyl (C_0-18N_1-6O_0-6),

cycloalkyl/cycloheteroalkyl (C_3-8N_1-3O_0-3), aryl/heteroaryl (C_3-14N_1-3).

108

109

110

X = N or O; R^1,4 = alkylene/heteroalkylene (C_0-18N_0-6O_0-6),

cycloalkylene/cycloheteroalkylene (C_3-8N_0-3O_0-3), arylene/heteroalkylene

(C_3-14N_0-3); R^2,3,5,6 = H, alkyl/heteroalkyl (C_0-18N_1-6O_0-6),

cycloalkyl/cycloheteroalkyl (C_3-8N_1-3O_0-3), aryl/heteroaryl (C_3-14N_1-3).

As previously stated, the admixtures of this invention, as depicted by Formula 1, contain chelate complexes of metals with hydroxycarboxylic acid-derived ligands, as exemplified by but not limited to metal-hydroxycarboxylate complexes. While the scientific literature describes the characterization and uses of metal-hydroxycarboxylate complexes in biological systems and environmental settings, there is no prior art on the use of metal-hydroxycarboxylate as admixtures for cements. See, Lajunen et al., Stability constants for alpha-hydroxycarboxylic acid complexes with protons and metal ions and the accompanying enthalpy changes—Part I: Aromatic ortho-hydroxycarboxylic acids, 1997 Pure Appl. Chem, 69: 329-381: Portanova et al., Critical evaluation of stability constants for alpha-hydroxycarboxylic acid complexes with protons and metal ions and the accompanying enthalpy changes—Part II: Aliphatic 2-hydroxycarboxylic acids, 2003 Pure Appl. Chem. 75: 495-540; O. Happel et al., Separation and characterization of aluminium malate species by ion chromatography, 2008: Anal. Bioanal. Chem. 392: 1373-1381; Dakanali, et al., A novel dinuclear species in the aqueous distribution of aluminum in the presence of citrate, 2003 Inorg. Chem. 42: 252-254; Matzapetakis et al., Synthesis, structural characterization, and solution behavior of the first mononuclear, aqueous aluminum citrate complex, 1999 Inorg. Chem. 38: 618-619; Sheikh-Osman et al., Aluminum carboxylates in aqueous solutions, 1993 J. Chem. Soc. Dalton Trans. 3229-3223; Feng et al., Aluminum citrate: Isolation and structural characterization of a stable trinuclear complex, 1990: Inorg. Chem. 29: 408-411: Motekaitis et al., Complexes of aluminum(III) with hydroxy carboxylic acids, 1984 Inorg. Chem. 23: 18-23; G. Bandoli et al., Mononuclear six-coordinated Ga(III) complexes, 2009 Coord. Chem. Rev. 253: 56-77; N. Yang, H. Sun, Biocoordination chemist, of bismuth: Recent advances, 2007 Coord. Chem. Rev. 251: 2354-2366); Sadler et al., Coordination chemistry of metals in medicine: Target sites for bismuth, 1999 Coord. Chem. Rev. 185-186: 689-709; Asato et al., Synthesis, structure, and spectroscopic properties of bismuth citrate compounds and the bismuth-containing ulcer-healing agent colloidal bismuth subcitrate (CBS), 1995 Inorg. Chem. 34: 2447-2454); Szczepaniak, et al., Use of bismuth ion-selective electrode for investigation of bismuth complexes of citric and malic acids, 1986 Talanta, 33: 371-373; Tomita et al. A water-soluble titanium complex for the selective synthesis of nanocrystalline brookite, rutile, and anatase by a hydrothermal method, 2006 Angew. Chem. Int. Ed. 45: 2378-2381; Deng, et al., pH-Dependent isolations and spectroscopic, structural, and thermal studies of titanium citrate complexes, 2004: Inorg. Chem. 43: 6266-6273; Todorovskya et al. On the chemical nature of lanthanum—titanium citric complexes, precursors of La₂Ti₂O₇, 2004 Mater. Lett. 58: 3559-3563; Ruzdic et al., Coordination properties of α-hydroxy carboxylic acids. Part I. Binuclear niobium(V) complex acids and some salts, 1984 Inorg. Chim. Acta, 88: 99-103; Brnicevic et al., Coordination complexes of niobium and tantalum. XI. Crystalline malato complexes of niobium(V), 1971 J. Less Common Metal. 23: 61-66; J. J. Lingane, Polarographic investigation of oxalate, citrate and tartrate complexes of ferric and ferrous iron, J. Am. Chem. Soc. 68: 2448-2454; Zhang et al., Syntheses, spectroscopies and structures of zinc complexes with malate, 2009 Inorg. Chim. Acta 362: 2643-2649; L. Meites, Polarographic studies of metal complexes. V. The cadmium(II), zinc(II) and iron(III) citrates, 1951 J. Am. Chem. Soc. 73: 3727-3732; Biagioli et al., Molecular structure, characterization and reactivity of dioxo complexes formed by vanadium(V) with α-hydroxycarboxylate ligands, 2000 Inorg. Chim. Acta 310:1-9); Zhou et al., Syntheses, crystal structures and biological relevance of glycolato and S-lactato molybdates, 2004 J. Inorg. Biochem. 98: 1037-1044); -H. Zhou et al., Synthesis and characterization of homochiral polymeric S-malatomolvbdate(VI), 2002 J. Inorg. Biochem. 90: 137-143; Zhang et al., pH- and mol-ratio dependent tungsten(VI)-citrate speciation from aqueous solutions: syntheses, spectroscopic properties and crystal structures, 2003 Inorg. Chim. Acta 351: 311-318; and Zhou et al. Tungsten-malate interaction. Synthesis, spectroscopic and structural studies of homochiral S-malato tungstate(VI), Λ-Na₃[WO₂H(S-mal)₂], 2001 Inorg. Chim. Acta 314: 184-188.

Similarly, while the patent literature describes the use of metal-hydroxycarboxylate complexes as pharmaceutical agents, cosmetics agents, and as modifiers for textiles, polymers and minerals, there is no prior art relating to the use of metal-hydroxycarboxylate complexes as admixtures for cements. The use of hydroxycarboxylate complexes of aluminum, bismuth, chromium, iron, magnesium and zinc as medicinal agents is described in U.S. Pat. No. 3,200,136. U.S. Pat. No. 6,903,235, U.S. Pat. No. 2,644,828, U.S. Pat. No. 7,005,531, U.S. Pat. No. 5,008,256, U.S. Pat. No. 5,206,265, U.S. Pat. No. 7,767,851, U.S. Pat. No. 3,591,616, U.S. Pat. No. 6,903,235, U.S. Pat. No. 5,165,914, U.S. Pat. No. 1,964,696, U.S. Pat. No. 3,506,761. G.B. Patent 843865 and G.B. Patent 949405. The use of hydroxycarboxylate complexes of aluminum, magnesium, titanium and zirconium as astringent and antiperspirant agents is described in U.S. Pat. No. 3,090,728, U.S. Pat. No. 2,498,514, U.S. Pat. No. 4,021,536, U.S. Pat. No. 391,176, U.S. Pat. No. 3,712,948, U.S. Pat. No. 3,734,940, U.S. Pat. No. 6,632,421 and G.B. Patent 843865. The use of hydroxycarboxylate complexes of iron as solvents for cellulose is described in U.S. Pat. No. 4,265,675 and U.S. Pat. No. 4,705,876. The use of hydroxycarboxylate complexes of aluminum as crosslinking agents for polymers is described in U.S. Pat. No. 4,601,340 and U.S. Pat. No. 5,559,263. The use of hydroxycarboxylate complexes of aluminum, chromium, iron and zirconium as drilling aids for petroleum recovery is described in U.S. Pat. No. 5,532,211, U.S. Pat. No. 4,129,183 and U.S. Pat. No. 3,843,524

Examples of known metal-hydroxycarboxylate complexes of metals from the scandium family (111), titanium family (112), vanadium family (113), chromium family (114), manganese, iron, cobalt, nickel, copper and zinc families (115), boron family (116), carbon family (117), and nitrogen family (118) are provided in Table 8.

TABLE 8

Examples of Metal-Hydroxycarboxylate Complexes

[La^III(CitH₋₃)] NH₄[La^III(CitH₋₄)]

111

(NH₄)₂[Ti(GlyH₋₂)₃] (NH₄)₂[Ti(LacH₋₂)₃] Na₂[Ti(CitH₋₂)₃] Na₃[Ti(CitH₋₃)(CitH₋₂)₂]

Na₄[Ti(CitH₋₃)₂(CitH₋₂)] Na₆[Ti(CitH₋₄)(CitH₋₃)₂] K₅[Ti(CitH₋₃)₃] Na₈[Ti(CitH₋₄)₃]

(NH₄)₆[Ti₄(O₂)₄(   O)₂(GlyH₋₂)₄(GlyH₋₁)₂] (NH₄)₄[Ti₂(O₂)₂(CitH₋₄)₂]

Ba₂(NH₄)₂[Ti₄(O₂)₄(CitH₋₄)₂(CitH₋₃)₂] (NH₄)₈[Ti₄(O₂)₄(CitH₋₄)₄]

Na₄[Zr₂(LacH₋₂)₆] Na₄[Zr₂(LacH₋₂)₆]

112

Rb₂[{V^VO₂(GlyH₋₂)}₂] Cs₂[{V^VO₂(LacH₋₂)}₂] Cs₂[{V^VO₂(MalH₋₂)}₂]

NH₄[Nb^V₂O₄(GlyH₋₁)(GlyH₋₂)] NH₄[Nb^V₂O₄(LacH₋₁)(LacH₋₂)] NH₄(Nb^V₂O₃(MalH₋₂)(MalH₋₃)]

K[Nb^V₂O₂(OH)(MalH₋₃)₂] Li[Nb^V₂O(MalH₋₃)₃] Ca[Nb₂O₂[TarH₋₄]₂]

113

Py₂[Cr^III(CitH₋₃)(CitH₋₂)]

K₂[Mo^VIO₂(GlyH₋₂)₂] K₂[Mo^VIO₂(LacH₋₂)₂] Na₃[Mo^VIO₂(MalH₋₂)(MalH₋₃)]

(NH₄)₂[Mo^VIO₂(MalH₋₂)₂] (NH₄)₄[Mo^VIO₂(MalH₋₃)₂] (NH₄)₄[Mo^VI₄O₁₁(MalH₋₃)₂]

K₄[(Mo^VIO₂)₂O(CitH₋₃)₂] K₂Na₄[(Mo^VIO₂)₂O(CitH₋₄)₂]

Na₂[W^VIO₂(CitH₋₂)₂] Na₃[W^VIO₂(MalH₋₂)(MalH₋₃)] NaK₃[W^VI₂O₅(CitH₋₃)₂] K₄[W^VIO₃(CitH₋₄)]

114

[Fe^III₂(MalH₋₃)₂)] Ca[Fe^III₂(MalH₋₄)₂] K₃[Fe^III₃(MalH₋₃)₄] K[Fe^III₂(MalH₋₄)•(MalH₋₃)]

[Fe^III(MalH₋₂)•(Mal₋₁)] [Fe^II(CitH₋₂)] [F^III(CitH₋₂)]NO₃ [Fe^III(CitH₋₃)] [Fe^III₂(CitH₋₂)₃]

Na[Fe^III(CitH₋₄)] K₃[Fe^III(CitH₋₃)₂] [Fe^III(OH)(H₂PO₄)(CitH₋₁)]

Na₂[Fe^III(OH)(H₂PO₄)₂(CitH₋₂)] Na₃[Fe^III(H₂PO₄)₂(CitH₋₂)₂]

[Zn(MalH₋₁)₂(H₂O)₂] [Zn₂(MalH₋₂)₂(H₂O)₄] (NH₄)[Zn(MalH₋₁)₃] (NH₄)₂[Zn(MalH₋₂)₂]

115

Li[B(MalH₋₂)₂] Zn[B(CitH₋₂)₂]₂ Rb[B(SalH₋₂)₂]

[Al(GlyH₋₂)]NO₃ Na[Al(GlyH₋₂)₂] Na₃[Al(GlyH₋₂)₃] [Al(LacH₋₂)]NO₃ Na[Al(LacH₋₂)₂]

Na₃[Al(LacH₋₂)₃] [Al(MalH₋₂)(MalH₋₁)] Na[Al₂(MalH₋₂)₂(MalH₋₃)] Na₃[Al₃(MalH₋₃)₄]

Na[Al₂(MalH₋₄)(MalH₋₃)] Na₂[Al₂(MalH₋₄)₂] Na[Al(CitH₋₂)] [Al(CitH₋₃)] [Al₂(CitH₋₂)₃]

K₄[Al₂(CitH₋₃)₂(CitH₋₄)] K₄[Al₃(CitH₋₃)₃(OH)] K[Al[CitH₋₄)] Na₅[Al[CitH₋₄)₂] Na₄[Al(CitH₋₃)(CitH₋₄)]

Na₇[Al₃(CitH₋₄)₃(OH)₄] K₃[Al(CitH₋₃)₂] Na[Al(TarH₋₄)] Na[Al(TarH₋₂)₂] Na₄[Al(TarH₋₃)(TarH₋₄)]

Na₇[Al(TarH₋₄)(TarH₋₃)₂] Na₈[Al(TarH₋₄)₂(TarH₋₃) Na₉[Al(TarH₋₄)₃] [Al(MucH₋₃)] K[Al(MucH₋₄)]

116

Na₂[Ge^IV(MalH₋₃)₂] Na₂[Ge^IV(CitH₋₃)₂] [Ge^IV(CitH₋₃)Cl(Bipy)]

117

[Bi(LacH₁)₃] [Bi(MalH₋₃)] (NH₄)₃[Bi(MalH₋₃)₂] (NH₄)₈[Bi₂(CitH₋₄)₂(CitH₋₃)₂(H₂O)₄]

K₅[Bi₂(CitH₋₄)₂(CitH₋₃)] K[Bi(CitH₋₄)₂] KNH₄[Bi₂(CitH₋₄)₂] K₆[Bi₆O₄(CitH₋₄)₄] K₁₂[Bi₁₂O₈(CitH₋₄)₈]

[Bi(TarH₋₁)(TarH₋₂)] NH₄[Bi(TarH₋₂)₂] [Bi₂(SalH₋₁)₆(Bipy)₂] [Bi₂(SalH₋₁)₂(SalH₋₂)₂(Phen)₂]

118

Notes.

GlyH_−x is glycolate anion;

LacH_−x is lactate anion;

MalH_−x is malate anion;

CitH_−x is citrate anion;

TarH_−x is tartarate anion;

MucH_−x is mucate anion;

SalH_−x is salicylate anion;

Phen is 1,10-phenanthroline;

Bipy is 2,2′-bipyridine

In one aspect of the present invention, there is provided a composition comprising a cement admixture comprising at least one metal complex represented by the formula M_a[N_b(HCA)_c], wherein: M is a metal selected from the group consisting of lithium, sodium, potassium, magnesium, calcium, strontium, barium and combinations thereof; N is a metal selected from the group consisting of aluminum, iron, bismuth and combinations t hereof: HCA is a hydroxycarboxylic acid selected from the group consisting of glyoxylic acid hydrate, glycolic acid, lactic acid, 2-hydroxybutyric acid and combinations thereof; a is an integer with a value of 1 to 100; b is an integer with a value of 1 to 10; and c is an integer with a value of 1 to 100, wherein the composition is capable of improving properties of a hydraulic cement.

In one embodiment, M is selected from the group consisting of lithium, sodium, potassium and combinations thereof; and HCA is selected from the group consisting of glyoxylic acid hydrate, glycolic acid, lactic acid and combinations thereof.

In another embodiment, M is selected from the group consisting of sodium, potassium and combinations thereof; N is selected from the group consisting of aluminum, bismuth and combinations thereof; HCA is lactic acid; a is an integer with a value of 1 to 50; b is an integer with a value of 1 to 5; and c is an integer with a value of 1 to 50.

In a further embodiment, M is sodium; N is aluminum; a is an integer with a value of 1 to 30; b is an integer with a value of 1 to 3; and c is an integer with a value of 1 to 30.

In another aspect of the present invention, there is provided a composition comprising a cement admixture comprising at least one metal complex represented by the formula M_a[N_b(HCA)_c], wherein: M is a metal selected from the group consisting of lithium, sodium, potassium, magnesium, calcium, strontium, barium, and combinations thereof; N is a metal selected from the group consisting of aluminum, iron, bismuth and combinations thereof; HCA is a hydroxycarboxylic acid selected from the group consisting of malic acid, tartronic acid, dihydroxymalonic acid and combinations thereof; a is an integer with a value of 1 to 100; b is an integer with a value of 1 to 10; and c is an integer with a value of 1 to 50, wherein the composition is capable of improving properties of a hydraulic cement.

In one embodiment, M is selected from the group consisting of lithium, sodium, potassium and combinations thereof; and HCA is selected from the group consisting of malic acid, tartronic acid and combinations thereof.

In another embodiment, M is selected from the group consisting of sodium, potassium and combinations thereof; N is selected from the group consisting of aluminum, bismuth and combinations thereof; a is an integer with a value of 1 to 80; b is an integer with a value of 1 to 5; and c is an integer with a value of 1 to 40.

In a further embodiment, M is sodium; N is aluminum; a is an integer with a value of 1 to 40; b is an integer with a value of 1 to 3; and c is an integer with a value of 1 to 30.

In a further aspect of the present invention, there is provided a composition comprising a cement admixture comprising at least one metal complex represented by the formula M_a[N_b(HCA)_c], wherein: M is a metal selected from the group consisting of lithium, sodium, potassium, magnesium, calcium, strontium, barium and combinations thereof; N is a metal selected from the group consisting of aluminum, iron, bismuth and combinations thereof; HCA is a hydroxycarboxylic acid selected from the group consisting of citric acid, isocitric acid, hydroxycitric acid and combinations thereof; a is an integer with a value of 1 to 100; b is an integer with a value of 1 to 10; and c is an integer with a value of 1 to 40, wherein the composition is capable of improving properties of a hydraulic cement.

In one embodiment, M is selected from the group consisting of lithium, sodium, potassium and combinations thereof; and HCA is selected from the group consisting of citric acid, isocitric acid and combinations thereof.

In another embodiment, M is selected from the group consisting of sodium, potassium and combinations thereof: N is selected from the group consisting of aluminum, bismuth and combinations thereof; a is an integer with a value of 1 to 50; b is an integer with a value of 1 to 5; and c is an integer with a value of 1 to 40.

In a further embodiment, M is sodium; N is aluminum; a is an integer with a value of 1 to 30; b is an integer with a value of 1 to 3; and c is an integer with a value of 1 to 30.

The aspects and embodiments of the invention described above have the ability to improve the properties of hardness and compressive strength of a hydraulic cement.

Examples of hydraulic cements that may be improved with the aspects and embodiments of the present invention described above include, without limitation, coal fly ash, coal bottom ash, coal boiler slag, steel slag, Portland cement, Portland-type cements, and combinations thereof.

The admixtures of the present invention can be prepared by a variety of methods, including but not limited to:

(i) The reaction of a group IIA, IIIA, IVA, VA, IB, IIB, IIIB, IVB, VB, VIIB, VIIB and/or VIIIB metal, and/or metal oxide, hydroxide, carbonate and/or basic carbonate with one or more hydroxycarboxylic acid-derived ligands, as exemplified by but not limited to:

• • (a) 2Al+2Cit→2-[Al(CitH₋₃)]+3H₂↑;
  • (b) Al₂O₃+4Mal→2[Al(MalH₋₂)(MalH₋₁)]+3H₂O;
  • (c) 2Al(OH)₃+3Cit→[Al₂(CitH₋₂)₃]+6H₂O;
  • (d) Fe^IICO₃+Cit→[Fe^II(CitH₋₂)]+CO₂↑+H₂O; and
  • (e) (BiO)₂CO₃+2Mal→2[Bi(MalH₋₃)]+CO₂↑+3H₂O.

(ii) The reaction of a group IA and/or IIA metal oxide, hydroxide, carbonate, basic carbonate and/or hydrogencarbonate, with a group IIA, IIIA, IVA, VA, IB, IIB, IIIB, IVB, VB, VIIB, VIIB and/or VIIIB metal oxide, and one or more hydroxycarboxylic acid-derived ligands, as exemplified by but not limited to:

• • (a) MgO+MoO₃+2Lac→Mg[MoO₂(LacH₋₂)₂]+2H₂O;
  • (b) KOH+Nb₂O₅+2Mal→K[Nb₂O₂(OH)(MalH₋₃)₂]+3H₂O;
  • (c) Ca(OH)₂+B₂O₃+4Mal→Ca[B(MalH₂)₂]₂+5H₂O;
  • (d) 4NaOH+2Ca(OH)₂+Al₂O₃+4Tar→2CaNa₂[Al(TarH₋₃)(TarH₋₄)]+11H₂O;
  • (e) Li₂CO₃+2Nb₂O₅+6Mal→2Li[Nb₂O(MalH₋₃)₃]+CO₂↑+9H₂O; and
  • (f) NaHCO₃+Al₂O₃+3Mal→Na[Al₂(MalH₋₂)₂(MalH₋₃)]+CO₂↑+4H₂O.

(iii) The reaction of a group IA and/or IIA metal oxide, hydroxide, carbonate, basic carbonate and/or hydrogencarbonate, with a group IIA, IIIA, IVA, VA, IB, IIB, IIIB, IVB, VB, VIB, VIIB and/or VIIIB metal hydroxide, and one or more hydroxycarboxylic acid-derived ligands, as exemplified by but not limited to:

(a) BaO+2Fe^III(OH)₃+Mal→Ba[Fe^III₂(MalH₋₄)₂]+7H₂O;

• • (b) Mg(OH)₂+2B(OH)₃+4Cit→Zn[B(CitH₋₂)₂]₂+8H₂O;
  • (c) 4NaOH+2Zr(OH)₄+6Lac→Na₄[Zr₂(LacH₋₂)₆]+10H₂O;
  • (d) 5K₂CO₃+4Bi(OH)₃+6Cit→2K₅[Bi₂(CitH₋₄)₂(CitH₋₃)]+5CO₂→+17H₂O; and
  • (e) 2NaHCO₃+Zn(OH)₂+2Mal→Na₂[Zn(MalH₋₂)₂]+2CO₂↑+4H₂O.

(iv) The reaction of a group IA and/or IIA metal oxide, hydroxide, carbonate, basic carbonate and/or hydrogencarbonate, with a group IIA, IIIA, IVA, VA, IB, IIB, IIIB, IVB, VB, VIB, VIIB and/or VIIIB metal carbonate and/or basic carbonate, and one or more hydroxycarboxylic acid-derived ligands, as exemplified by but not limited to:

• • (a) 10NaOH+Zn₅(OH)₆(CO₃)₂+10Mal→5Na₂[Zn(MalH₋₂)₂]+2CO₂→+18H₂O;
  • (b) 3K₂CO₃+3(BiO)₂CO₃+4Cit→K₆[Bi₆O₄(CitH₋₄)₄]+6CO₂↑+8H₂O; and
  • (c) 3KHCO₃+FeCO₃+2Cit→K₃[Fe^III(CitH₋₃)₂]+4CO₂↑+4H₂O.

(v) The reaction of a metal oxometallate of a group IA and/or IIA metal with a group IIA, IIIA, IVA, VA, IB, IIB, IIIB, IVB, VB, VIB, VIIB and/or VIIIB metal, and one or more hydroxycarboxylic acid-derived ligands, with or without the presence of a group IA and/or IIA metal hydroxide, carbonate, basic carbonate and/or hydrogencarbonate, and with or without the presence of a group IIA, IIIA, IVA, VA, IB, IIB, IIIB, IVB, VB, VIIB, VIIB and/or VIIIB metal oxide, hydroxide, carbonate and/or basic carbonate, as exemplified by but not limited to:

• • (a) Na₂Al₂O₄+4Gly→2Na[Al(GlyH₋₂)₂]+4HO;
  • (b) Na₂Al₂O₄+4NaOH+6Gly→2Na₃[Al(GlyH₋₂)₃]+8H₂O;
  • (c) Li₂TiO₃+LiOH+3Cit→Li₃[Ti(CitH₋₃)(CitH₋₂)₂]+4H₂O; and
  • (d) 2KNbO₃+Nb₂O₅+4Mal→2K[Nb^v₂O₂(OH)(MalH₋₃)₂]+5H₂O.

(vi) The reaction of a salt of a group IA and/or IIA metal with one or more hydroxycarboxylic acid-derived ligands, with a group IIA, IIIA, IVA, VA, IB, IIB, IIIB, IVB, VB, VIB, VIIB and/or VIIIB metal, and/or metal oxide, hydroxide, carbonate and/or basic carbonate, with or without the presence of one or more hydroxycarboxylic acid-derived ligands, as exemplified by but not limited to:

• • (a) 4Na₂(TarH₋₂)+2Al→2Na₄[Al(TarH₋₃)(TarH₋₄)]+3H₂↑;
  • (b) 2NH₄(LacH₋₁)+TiO₂+Lac→(NH₄)₂[Ti(LacH₋₂)₃]+2H₂O;
  • (c) 4K₃(CitH₋₃)+6Bi₂O₃+4Cit→K₁₂[Bi₁₂O₈(CitH₋₄)₈]+10H₂O; and
  • (d) K₃(CitH₋₃)+3Al(OH)₃+2Cit→3K[Al(CitH₋₄)]+9H₂O.

(vii) The reaction of a group IA and/or IIA metal oxide, hydroxide, carbonate, basic carbonate and/or hydrogencarbonate, with the salt of a group IIA, IIIA, IVA, VA, IB, IIB, IIIB, IVB, VB, VIIB, VIIB and/or VIIIB metal with a group IIIA, IVA, VA, VIA and/or VIIA nonmetal, and one or more hydroxycarboxylic acid-derived ligands, with or without the presence of a group IIA, IIIA, IVA, VA, IB, IIB, IIIB, IVB, VB, VIB, VIIB and/or VIIIB metal oxide, hydroxide, carbonate and/or basic carbonate, as exemplified by but not limited to:

• • (a) 14NaOH+Al₂(SO₄)₃+4Cit→2Na₄[Al(CitH₋₃)(CitH₋₄)]+3Na₂SO₄+14H₂O;
  • (b) 3Ca(OH)₂+Al₂(SO₄)₃+4Mal→2[Al(MalH₋₂)(MalH₋₁)]+3CaSO₄↓+6H₂O; and
  • (c) 2NaOH+CaCO₃+ZnSO₄+2Mal→Na₂[Zn(MalH₋₂)₂]+CaSO4↓+CO₂↑+4H₂O.

(viii) The reaction of a group IA and/or IIA metal oxide, hydroxide, carbonate, basic carbonate and/or hydrogencarbonate, and/or a salt of a group IA and/or IIA metal with one or more hydroxycarboxylic acid-derived ligands, with an ore/mineral and/or mining byproduct and/or industrial byproduct containing a group IIA, IIIA, IVA, VA, IB, IIB, IIIB, IVB, VB, VIIB, VIIB and/or VIIIB metal, with or without one or more hydroxycarboxylic acid-derived ligands, as exemplified by but not limited to:

• • (a) 6Na(MalH₋₁)+3Al₂SiO₅ (Kyanite)+2Mal→2Na₃[Al₃(MalH₋₃)₄]+3SiO₂↓+9H₂O;
  • (b) 4Na₂(CitH₋₂)+Al₂Si₂O₅(OH)₄ (Kaolin)→2Na₄[Al(CitH₋₃)(CitH₋₄)]+2SiO₂↓+5H₂O; and
  • (c) 2K(CitH₋₁)+2K₂(CitH₋₂)+3Bi₂S₃ (Bismuthinite)+7O₂→K₆[Bi₆O₄(CitH₋₄)₄]+9S↓+5H₂O.

Reactions may be conducted using crude, partially-purified or substantially pure hydroxycarboxylic acid-derived ligand feedstocks. Crude and partially-purified feedstocks for hydroxycarboxylic acid-derived ligands are exemplified by, but not limited to:

(i) Crude, filtered, concentrated, crystallized and/or extracted fermentation broths containing hydroxycarboxylic acids such as glycolic, lactic, malic, citric, citramalic and/or tartaric acid. The fermentation production of hydroxycarboxylic acids is described in the publications, Berovic et al., Citric Acid Production, 2007 Annu. Rev. Biotechnol. 13: 303-343; Hofvendahl et al., Factors affecting the fermentative lactic acid production from renewable resources, 2007 Enzyme Microb. Technol. 26: 87-107; John et al., Fermentative production of lactic acid from biomass: An overview on process developments and future perspectives, 2007: Appl. Microbiol. Biotechnol. 74: 524-534; and Aristidou et al., Metabolic engineering applications to renewable resource utilization, 2000 Curr. Opin. Biotechnol. 11: 187-199);

(ii) Crude, filtered, concentrated, crystallized and/or extracted fruit juices and fermented fruit juices containing hydroxycarboxylic acids such as glycolic, lactic, malic, citric, citramalic and/or tartaric acid;

(iii) Crude, filtered, concentrated, crystallized and/or extracted reaction mixtures resulting from the catalytic and/or non-catalytic aerobic and/or non-aerobic oxidation of monosaccharides, oligosaccharides, polysaccharides, fats, oils, resins, extractives, biomass components, and/or biomass. These oxidation reactions are described by Collinson et al., The catalytic oxidation of biomass to new materials focusing on starch, cellulose and lignin, 2010 Coord. Chem. Rev. 254: 1854-1870; and Aouf et al., Low Catalyst loadings for the production of carboxylic acid from polysaccharides and hydrogen peroxide, 2010 Chem. Sus. Chem. 3: 1200-1203); and

(iv) Crude, filtered, concentrated, crystallized and/or extracted reaction mixtures resulting from the catalytic and/or non-catalytic interconversion of hydroxycarboxylic acids and their derivatives such as esters, thioesters, amides, N-substituted amides, imides, N-acylhydrazines and hydroxamic acids, as exemplified by, but not limited to the partial esterification and/or partial amidation of hydroxypolycarboxylic acids with aliphatic alcohols and/or aliphatic amines respectively; and the partial hydrolysis and/or partial aminolysis of polyalkyl hydroxypolycarboxylates to form the corresponding partial esters or ester amides.

Reactions may be conducted in solution or in suspension, in a variety of solvents, including but not limited to water, a mixture of water and an organic solvent exemplified by but not limited to methanol, ethanol, propan-1-ol, propan-2-ol (isopropanol), ethane-1,2-diol (ethylene glycol), propane-1,2,3-triol (glycerol). 2-ethoxyethanol (diethylene glycol), and 2-(2′-ethoxyethoxy)ethanol (triethylene glycol), or a water-free organic solvent exemplified by but not limited to methanol, ethanol, propan-1-ol, propan-2-ol (isopropanol), ethane-1,2-diol (ethylene glycol), propane-1,2,3-triol (glycerol), 2-ethoxyethanol (diethylene glycol), and 2-(2′-ethoxyethoxy)ethanol (triethylene glycol). When a mixture of water and organic solvent is used, the water content may range from 5% to 95% v/v, preferably 15% to 85% v/v, and more preferably 25% to 75% v/v.

When a solvent is used, the substrates and/or product(s) may be soluble or insoluble to varying degrees, and the reaction system may vary from homogeneous to heterogeneous. Furthermore, the nature of the reaction mixture may change during the course of the reaction, as exemplified by but not limited to the dissolution of initially insoluble or partially soluble reactants, and/or the transient precipitation/crystallization and subsequent dissolution of reaction intermediate(s) and/or the precipitation/crystallization of product(s).

When a solvent is used, the net concentration of the reactants is 5-80% w/w, and preferably 10-60% w/w, and more preferably 20-40% w/w.

Reactions may be conducted in the absence of solvent, or in the presence of a small amount (<20% w/w) of a solvent/adjuvant. Reactions may be performed by blending, grinding or milling a mixture of the reactants, with or without the addition of the solvent/adjuvant. The solvent/adjuvant is exemplified by but not limited to water, methanol, ethanol, propan-1-ol, propan-2-ol (isopropanol), ethane-1,2-diol (ethylene glycol), propane-1,2,3-triol (glycerol), 2-ethoxyethanol (diethylene glycol), and 2-(2′-ethoxyethoxy)ethanol (triethylene glycol).

Reactions may be conducted such that water and/or organic solvents are partially or fully removed by evaporation/distillation during the course of the reaction, in order to obtain a soluble concentrate of the product, a slurry of the product, a paste of the product, or a substantially or completely dry solid or semi-solid product.

Reactions may be conducted such that evolved gases, as exemplified by carbon dioxide and hydrogen, are partially or fully removed by sparging with a gas such as air, nitrogen or helium, or by the application of a vacuum of 0.01-0.98 bar.

Reactions may be conducted with sparging with a gas such as air or oxygen, when oxidizing conditions are desired—for example when the oxidation of a sulfide-containing reactant to elemental sulfur is desired. Alternatively, sparging with nitrogen or helium may be used when suppression of oxidation is desired—for example when complexes of iron(II) are being prepared and prevention of oxidation to iron(III) is needed.

Reactions may be conducted at ambient temperature, or at temperatures of 243-473 K, and preferably 273-423 K, and more preferably 293-373 K.

Reactions may be conducted at ambient pressure, or at pressures of 0.1-20 bar, and preferably 0.5-10 bar, and more preferably 1-5 bar.

Reactions may be conducted in non-pressurized or pressurized batch, semi-continuous or continuous glass or metal reactors, exemplified by but not limited to stirred tank reactors, packed bed reactors, fluidized bed reactors, bead mills, jet mills, homogenizers, colloid mills, ball mills, rotor-stator mixers, pug mills, and screw extruders.

The admixtures of the present invention may be prepared to contain one or more complexes as described above by Formula 1. The admixtures may be used as prepared, or may be further processed, as exemplified by but not limited to:

(i) Clarification/filtration of suspensions to furnish the admixtures as solutions with product concentrations of 10-80% w/w, and preferably 15-70% w/w, and more preferably 20-60% w/w. Clarification/filtration may be accomplished by various methods, including but not limited to plate filtration, fabric filtration, tubular filtration, leaf filtration, filter pressing, centrifugal filtration and centrifugation.

(ii) Concentration of solutions or suspensions to furnish the admixtures as soluble or suspension concentrates, or slurries, with product concentrations of 20-90% w/w, and preferably 30-80% w/w, and more preferably 40-70% w/w. The removal of solvent may be accomplished by various methods, including but not limited to rotary evaporation, rising film evaporation, circulation evaporation, falling film evaporation, fluidized bed evaporation, plate evaporation, spiral tube evaporation, and reverse osmosis. Furthermore, concentration may be combined with solvent exchange.

(iii) Crystallization of solutions or suspensions to furnish the admixtures as crystalline or semi-crystalline products. These crystalline products may be relatively pure and contain predominantly one complex, or may be semi-pure and contain a mixture of distinct complexes. Furthermore, the crystalline products may be anhydrous or may be hydrated/solvated. Crystallization may be accomplished by accomplished various methods, including but not limited to cooling and/or evaporative methods, and using such equipment as stirred tank crystallizers and fluidized bed crystallizers. Crystallization may be accomplished by heating solutions or suspensions up to 293-373 K, and preferably to 303-363 K, and more preferably to 313-353 K, and concentrating the solution or suspension such that the product concentration is 20-90% w/w, and preferably 30-80% w/w, and more preferably 40-70% w/w. This may be followed by cooling to 263-313 K, and preferably to 273-303 K, and more preferably to 278-228 K. This may be further combined with seeding with appropriate seed crystals, comprised of the desired complex, or of an isomorphous crystalline compound. This may be further combined with the addition of an anti-solvent, including but not limited to methanol, ethanol, propan-1-ol, propan-2-ol (isopropanol), ethane-1,2-diol (ethylene glycol), propane-1,2,3-triol (glycerol), 2-ethoxyethanol (diethylene glycol), and 2-(2′-ethoxyethoxy)ethanol (triethylene glycol). The crystalline suspension may be used as is, with or without solvent exchange. Alternatively, the crystalline product may be separated by sedimentation/decantation, centrifugation and/or filtration. The separated crystalline product may be partially or fully dried to furnish an anhydrous or hydrated/solvated solid crystalline or semi-crystalline product. Drying may be accomplished by various methods, including but not limited to plate drying, drum drying, rotary louvre drying, rotary steam tube drying, and fluidized bed drying.

(iv) Concentration of solutions or suspensions, followed by granulation and/or extrusion and/or partial or complete drying, to furnish the admixtures as powders, flakes, granules or pellets. The products may be amorphous, semi-crystalline or crystalline, and may be anhydrous or hydrated/solvated. Drying may be accomplished by various methods, including but not limited to plate drying, drum drying, rotary louvre drying, rotary steam tube drying, fluidized bed drying and spray drying. Drying may be integrated with flaking, granulation, extrusion and/or powdering.

(v) Adsorption of solutions, suspensions or slurries onto solid carriers, followed by granulation and/or extrusion and/or partial or complete drying, to furnish the admixtures as solid-supported powders, flakes, granules or pellets, with product concentrations of 10-90% w/w, and preferably 20-80% w/w, and more preferably 30-70% w/w. The carrier is exemplified by, but not limited to:

• • (a) a biomass product such as wood flour, wood sawdust, peat, coconut coir and coconut shell powder;
  • (b) a rock or mineral product such as kaolin, calcined kaolin, china clay, perlite, expanded perlite, exfoliated vermiculite, bauxite, calcined bauxite, red mud, brucite, clay, montmorillonite clay, smectite clay, illite clay, chlorite clay, bentonite clay, halloysite clay, imogolite clay, diatomaceous earth, volcanic ash, tuff, chalk, limestone and gypsum; and
  • (c) a combustion product such as rice hull ash, sugarcane bagasse ash and fly ash.

The product concentration in the solution, suspension or slurry is 10-90% w/w, and preferably 15-80% w/w, and more preferably 20-70% w/w. Adsorption may be accomplished by various methods, including but not limited to drum coating and fluidized bed coating. Drying may be accomplished by various methods, including but not limited to plate drying, drum drying, rotary louvre drying, and fluidized bed drying.

The admixtures of the present invention, prepared as described above, may be employed as admixtures for hydraulic cements in a number of ways, as exemplified by, but not limited to:

(i) Addition of admixtures, as solutions, suspensions, slurries or solids, during any stage of the preparation of the cement paste, mortar or concrete, and as typified by the addition of admixtures to the mixing water; and

(ii) Blending of admixtures as solids with dry cements or cement components (OPC and/or SCMs) and/or aggregates to form premixes that may be stored as desired, and made into a cement paste, mortar or concrete when needed.

The admixtures of the present invention, prepared as described above, may be employed at dosages of 0.1-20% w/w (active solids with respect to the cement), and preferably 0.15-10% w/w, and more preferably 0.2-5% w/w.

The admixtures of the present invention, prepared as described above, may be combined together to form blended admixtures.

The admixtures of the present invention, prepared as described above, may be combined with conventional chemical admixtures as exemplified by, but not limited to water-reducers, superplasticizers, viscosity control agents, set accelerators, set retarders, rebar corrosion inhibiting agents, waterproofing agents, and air entraining agents.

The above examples are indicative of preformed complexes of metals with hydroxycarboxylic acid derivatives that are prepared as solutions, suspensions, slurries or solids, and are then subsequently used as admixtures for cement compositions. Alternatively, the same complexes may be formed in-situ in cement compositions by combining in the dry state, the individual precursors used to form the complexes, or combinations of the precursors, with the cement, mortar, grout or concrete components.

For example, in the case of the complex [Al(CitH₋₃)], aluminum(III) hydroxide (Al(OH)₃) and anhydrous citric acid (Cit) may be used as precursors. The required molar ratio (1:1 mol ratio of Al(OH)₃ and Cit) of these may be blended with fly ash C to produce a dry fly ash C—Al(OH)₃-Cit blend, which may be stored as required until used. When this blend is mixed with water, the precursors react to form the indicated complex in-situ, and this then exerts its effect(s) as a chemical admixture on the desired fly ash C cement.

Similarly, in the case of the complex Na₃[Al(GlyH₋₂)₃], sodium carbonate (Na₂CO₃) and aluminum(III) glycolate (Al(Gly)₃) may be used as precursors. The required molar ratio (3:2 mol ratio of Na₂CO₃ and Al(Gly)₃) of these may be blended with OPC and fly ash F respectively, and the obtained OPC-Na₂CO₃ and fly ash F—Al(Gly)₃ blends stored separately as a two-component cement, or combined to form a OPC-fly ash-Na₂CO₃—Al(Gly)₃ blended cement. As before, the addition of water, to a mixture of the separate OPC-Na₂CO₃ and fly ash F—Al(Gly)₃ products, or to the OPC-fly ash F—Na₂CO₃—Al(Gly)₃ mixture, results in the formation of the desired complex in-situ, and this exerts its action on the desired OPC-fly ash F blended cement.

EXAMPLES

Materials

Chemicals used in the following Examples were obtained from Sigma-Aldrich Corporation, St. Louis, Mo., USA, American Elements, Los Angeles, Calif., USA, and Reade Advanced Materials, Reno, Nev., USA. The following chemicals were: sodium hydroxide (NaOH, 99%, pellets); potassium hydroxide (KOH, 99%, pellets); lithium hydroxide (LiOH, 99%, powder); aluminum(III) hydroxide (Al(OH)₃, 99%, 18% water, powder); magnesium hydroxide (Mg(OH)₂, 99%, powder); calcium hydroxide (Ca(OH)₂, 97%, powder); iron(III) hydroxide (Fe(OH)₃, 98%, powder); aluminum(III) oxide (Al₂O₃, 99%, powder); bismuth(III) oxide (Bi₂O₂, 99%, powder); indium(III) oxide (In₂O₃, 99%, powder); gallium(III) oxide (Ga₂O₃, 99%, powder); zinc(II) oxide (ZnO, 99%, powder); zirconium(IV) hydroxide (Zr(OH)₄, 99%, powder); lanthanum(III) oxide (La₂O₃, 99%, powder); yttrium(III) oxide (Y₂O₃, 99%, powder); molybdenum(VI) oxide (MoO₃, 99%, powder); tungsten(VI) oxide (WO₃, 99%, powder); sodium carbonate (Na₂CO₃, 99%, powder); magnesium carbonate (MgCO₃, 99%, powder); calcium carbonate (CaCO₃, 99%, powder); aluminum(III) chloride hexahydrate (AlCl₃.6W, 98%, powder); dialuminum(III) chloride pentahydroxide (Al₂Cl(OH)₅, 95%, 50% w/w aqueous); aluminum(III) sulfate hexadecahydrate (Al₂(SO₄)₃.16W, 95%, powder); sodium aluminate(III) (Na₁₅Al₁₁O₂₄, 98%, powder); acetic acid (C₂H₄O₂, 99%, liquid); glycolic acid (C₂H₄O₃, 99%, 70% w/w aqueous liquid); DL-lactic acid (C₃H₆O₃, 99%, 90% w/w aqueous liquid); DL-malic acid (C₄H₆O₅, 99%, powder); citric acid (C₆H₈O₇, 99%, powder); tartaric acid (C₄H₆O₆, 99%, powder); DL-2-hydroxybutyric acid (C₄H₈O₃, 97%, liquid); DL-3-hydroxybutyric acid (C₄H₈O₃, 98%, liquid); DL-citramalic acid (C₅H₈O₅, 99%, powder); mucic acid (C₆H₁₀O₈, 99%, powder); caffeic acid (C₉H₈O₄, 98%, powder); chlorogenic acid (C₁₆H₁₈O₉, 95%, powder); 2,3-dihydroxybenzoic acid (C₇H₆O₄, 99%, powder); boric acid (H₃BO₃, 99%, powder); phosphoric acid (H₃PO₄, 99%, 85% w/w aqueous liquid).

SikaSet NC and SikaSet HE accelerating, water-reducing and superplasticizing admixtures, were obtained from Sika Corporation, Lyndhurst, N.J., USA. Pozzutec 20+ accelerating and water-reducing admixture was obtained from BASF Corporation, Florham Park, N.J., USA.

Type II OPC was obtained from Lehigh Southwest Cement Company, San Ramon, Calif., USA. Fly ash C and fly ash F were obtained from Boral Material Technologies, San Antonio, Tex., USA. Concrete sand was obtained from Graniterock, San Jose, Calif., USA. Limestone powder was obtained from Greymont Inc., Salt Lake City, Utah, USA. Basic oxygen furnace and electric arc furnace slags were obtained from Ecocem, Dublin, Ireland. Seawater brucite fines were obtained from the Moss Landing Business Park, Moss Landing, Calif., USA.

Methods:

Laboratory-scale (typically 4 or 8 g) admixture preparations were carried out using Radleys carousel reaction stations, fitted with 40 mL glass reaction vials, and reflux heads.

The performances of the admixtures with hydraulic cement compositions were assessed by forming and testing 3:1:1 (w/w) OPC-fly ash F-sand and 3:2 (w/w) fly ash C-sand mortars. Mortars were prepared in 0.5 or 1.0 kg batches. Cement components (OPC and fly ash F, or fly ash C alone) and sand were blended together at 139 rpm for 2 minutes, using a Gilson planetary mixer. Agitation was increased to 285 rpm, and a mixture of water and admixture added, and mixing continued for 2 minutes. Mixing was stopped, the sides of the mixing bowl scraped down, and mixing continued for 2 minutes.

Set time measurements were performed on fresh mortars using an ACME needle penetrometer. Mortar specimens were placed in 2×4 inch polypropylene cylinders, and measurements were performed at 292-294 K, 30-40% relative humidity.

Hardness measurements were performed on 2 inch mortar cubes with a Leica microhardness tester fitted with a Vickers pyramidal diamond head, loaded at 10, 50 and 100 N. Measurements were performed at 292-294 K, and 30-40% relative humidity. Mortars were cast in polypropylene cube molds, and cured at 292-294 K, 40-60% relative humidity, for 1 day.

Compressive strength tests were performed on 2 inch mortar cubes using an Instron instrument. Measurements were performed at 292-294 K, and 30-40% relative humidity. Mortars were cast in polypropylene cube molds, and cured at 292-294 K, 40-60% relative humidity, for 1 day, then at 292-294 K, 30-40% relative humidity, thereafter.

Linear shrinkage measurements were made on single or duplicate 4×12″ mortar bars, cast using 316 SS molds, cured at 292-294 K, 40-60% relative humidity, for 1, demolded and cured at 292-294 K, 40-60% relative humidity, for 1 day, then demolded and cured at 292-294 K, 40-60% relative humidity, thereafter.

Water permeability determinations were made using a Taywood instrument. Mortars were cast as 1×12″ bars, using 316 SS moulds, cured at 50% H, 295 K, 0-1 d, then demolded, cured at 292-294 K, and 40-60% RH, for 28 days, then sawn and cored with diamond tools to furnish 1″ thick disks. Specimens were de-aerated under 20 mbar vacuum for 20 hours, then water-saturated under 2 bar water pressure 2 hours, and measurements performed at water pressures of 5 and 10 bar, at 292-294 K.

Freeze-thaw resistance was evaluated as per ASTM C-666, wet method, using an Olson instrument. Mortars were cast as 3×12″ bars, using 316 SS molds, cured at 292-294 K, 40-60% relative humidity, for 1 day, then demolded and cured at 292-294 K, 40-60% relative humidity, thereafter.

Preparations:

The following examples illustrate the preparation of the aforementioned admixtures for use with hydraulic cement compositions.

In the following examples, the nominal formulas for the admixtures are provided, which are indicative only of the molar ratios of the reactants used in the preparations. As such, the formulas do not indicate the actual complexes present, but rather the overall chemical compositions. Furthermore, the admixtures are expected to contain mixtures of such complexes as described above, and as exemplified in Table 8.

For comparative purposes, cement compositions prepared with the admixtures of the present invention were compared with control compositions prepared with water alone, and with the commercial accelerating admixtures, SikaSet NC, SikaSet HE and Pozzutec 20+.

Admixtures C1-C11 were prepared as 40% w/w aqueous solutions or suspensions, using the □-hydroxycarboxylic acid, glycolic acid (Gly) as the ligand. Admixture C1 is sodium glycolate (Na₁(Gly)₁), admixture C2 is an aluminum glycolate complex (Al₁(Gly)₃), and admixtures 3-11 are sodium glycolatoaluminate(III) complexes (Na_xAl_y(Gly)_z, where x is between 1 and 5, y is between 1 and 2, and z is between 1 and 6). The formulation and preparation of the admixtures is detailed in Table 9, with representative examples (admixtures C1, C2 and C3-C11) provided below as Examples 1-3. The testing of the admixtures for OPC-fly ash F-sand and fly ash C-sand mortars is detailed in Tables 10 and 11 respectively. Mortars prepared with sodium glycolatoaluminate(III) admixtures achieved substantially greater hardness and compressive strength than those prepared with water, sodium glycolate, or the commercial SikaSet or Pozzutec admixtures.

The results show that glycolatoaluminate(III) complexes are useful as admixtures for hydraulic cement compositions, and that they improve setting, hardness and compressive strength.

Example 1

Admixture C1. Sodium Glycolate: Na₁(Gly)₁

Sodium hydroxide (2.78 g) was dissolved with stirring (340 rpm) in water (9.6 g) maintained at 293 K, glycolic acid (7.57 g) added over 1 minute, and stirring continued at 293 K for 22 hours. A clear solution was obtained, and this was diluted to 6% w/w solids for testing.

Example 2

Admixture C2. Aluminum(III) Glycolate: Al₁(Gly)₃

Aluminum(III) hydroxide (2.51 g) was suspended with stirring (340 rpm) in water (8.9 g) maintained at 343 K, glycolic acid (8.60 g) added over 1 minute, and stirring continued at 343 K for 70 hours. A white suspension was obtained, and this was diluted to 6% w/w solids for testing.

Example 3

Admixture C3. Sodium Glycolatoaluminate(III): Na₁Al₁(Gly)₁

Sodium hydroxide (1.19 g) was dissolved with stirring (340 rpm) in water (9.9 g) maintained at 293 K, glycolic acid (3.23 g) added over 2 minutes, and stirring continued for 15 minutes. Aluminum(III) hydroxide (5.65 g) was then added, the temperature raised to 343 K, and stirring continued for 70 hours. A white suspension was obtained, and this was diluted to 6% w/w solids for testing.

Admixtures C4-C11 were similarly prepared using the method of Example 3.

TABLE 9

Preparation and Properties of Admixtures C1-C11

Admixtures

Reactants (Mass in g)

Reaction Product

#

Mol Composition

NaOH

Al(OH)₃

Gly

Water

pH

Appearance

C1

Na₁(Gly)₁

2.78

—

7.57

9.6

11.8

Clear Solution

C2

Al₁(Gly)₃

—

2.51

8.60

8.9

3.2

White Suspension

C3

Na₁Al₁(Gly)₁

1.19

5.65

3.23

9.9

8.8

White Suspension

C4

Na₂Al₂(Gly)₃

1.39

3.31

5.68

9.6

8.1

White Suspension

C5

Na₃Al₂(Gly)₃

1.92

3.05

5.23

9.8

10.7

White Suspension

C6

Na₁Al₁(Gly)₂

1.20

2.84

6.50

9.5

8.5

White Suspension

C7

Na₃Al₂(Gly)₄

1.67

2.65

6.05

9.6

11.1

White Suspension

C8

Na₂Al₁(Gly)₃

1.67

1.99

6.82

9.5

8.0

White Suspension

C9

Na₃Al₁(Gly)₄

1.93

1.53

6.99

9.5

7.8

White Suspension

C10

Na₄Al₁(Gly)₄

2.38

1.42

6.48

9.7

8.1

White Suspension

C11

Na₅Al₁(Gly)₆

2.20

1.05

7.18

9.6

8.2

White Suspension

Notes.

Reaction conditions are detailed in Examples 1-3;

NaOH is sodium hydroxide;

Al(OH)₃ is aluminum(III) hydroxide;

Gly is glycolic acid;

W is water.

TABLE 10

1:1:3 (w/w) OPC-Fly Ash F-Sand Mortars made with Admixtures C1-C11

[Admixture]

Compressive

W/C

(% w/w)

Set Time

Hardness (MPa)

Strength (MPa)

#

(w/w)

In Stock

vs Cement

(min)

1 day

1 day

28 dayP20

Water

0.46

—

—

190

48

7.8

18.9

SNC

0.42

—

0.5

160

52

8.1

22.9

SHE

0.41

—

0.5

125

81

13.6

28.7

P20

0.42

—

0.5

110

93

14.0

32.4

C1

0.41

6.0

2.46

205

63

10.2

29.3

C2

0.41

6.0

2.46

165

78

13.6

30.5

C3

0.41

6.0

2.46

95

128

19.1

44.6

C4

0.41

6.0

2.46

90

121

18.8

43.2

C5

0.41

6.0

2.46

70

123

19.6

44.7

C6

0.41

6.0

2.46

70

138

20.3

45.9

C7

0.41

6.0

2.46

65

151

21.5

43.8

C8

0.41

6.0

2.46

75

130

18.1

40.9

C9

0.41

6.0

2.46

58

137

19.2

38.5

C10

0.41

6.0

2.46

43

119

17.8

36.4

C11

0.41

6.0

2.46

36

123

17.3

37.0

Notes:

W/C is the water-to-cement ratio;

Hardness is the Vickers indentation hardness;

SNC is SikaSet NC;

SHE is SikaSet HE;

P20 is Pozzutec 20+.

TABLE 11

2:3 (w/w) Fly Ash C-Sand Mortars made with Admixtures C1-C11

Compressive

[Admixture]

Strength

W/C

(% w/w)

Set Time

Hardness (MPa)

(MPa)

#

(w/w)

In Stock

vs Cement

(min)

1 day

1 day

28 day

Water

0.27

—

—

26

31

4.1

14.3

SNC

0.25

—

0.5

37

44

5.2

16.8

SHE

0.23

—

0.5

42

63

8.9

23.5

P20

0.24

—

0.5

33

71

9.5

26.0

C1

0.22

6.0

1.32

13

123

18.4

40.9

C2

0.22

6.0

1.32

46

107

15.0

35.2

C3

0.22

6.0

1.32

25

178

25.3

52.5

C4

0.22

6.0

1.32

23

188

26.7

54.7

C5

0.22

6.0

1.32

22

184

26.1

53.2

C6

0.22

6.0

1.32

28

179

25.3

53.3

C7

0.22

6.0

1.32

28

193

27.7

57.0

C8

0.22

6.0

1.32

32

201

28.6

59.2

C9

0.22

6.0

1.32

28

190

26.1

56.9

C10

0.22

6.0

1.32

34

181

24.8

53.5

C11

0.22

6.0

1.32

27

186

26.1

55.1

Notes:

W/C is the water-to-cement ratio;

Hardness is the Vickers indentation hardness;

SNC is SikaSet NC;

SHE is SikaSet HE;

P20 is Pozzutec 20+.

Admixtures C12-C20 were prepared as 40% w/w aqueous solutions or suspensions, using the α-hydroxycarboxylic acid, lactic acid (Lac) as the ligand. Admixture C12 is sodium lactate (Na₁(Lac)₁), admixture C13 is an aluminum lactate complex (Al₁(Lac)₃), and admixtures C14-C20 are sodium lactatoaluminate(III) complexes (Na_xAl_y(Lac)_z, where x is between 1 and 5, y is between 1 and 2, and z is between 1 and 6). The formulation and preparation of the admixtures is detailed in Table 12, with representative examples (admixtures C12, C13 and C14-C20) provided below as Examples 4-6. The testing of the admixtures for OPC-fly ash F-sand and fly ash C-sand mortars is detailed in Tables 13 and 14 respectively. Mortars prepared with sodium lactatoaluminate(III) admixtures achieved substantially greater hardness and compressive strength than those prepared with water, sodium lactate, or the commercial SikaSet or Pozzutec admixtures.

The results show that lactatoaluminate(III) complexes are useful as admixtures for hydraulic cement compositions, and that they improve setting, hardness and compressive strength.

Example 4

Admixture C12. Sodium Lactate: Na₁(Lac)₁

Sodium hydroxide (2.48 g) was dissolved with stirring (340 rpm) in water (11.3 g) maintained at 293 K, lactic acid (6.22 g) added over 1 minute, and stirring continued at 293 K for 22 hours. A clear solution was obtained, and this was diluted to 6% w/w solids for testing.

Example 5

Admixture C13. Aluminum(III) Lactate: Al₁(LAC)₃

Aluminum(III) hydroxide (2.21 g) was suspended with stirring (340 rpm) in water (10.8 g) maintained at 343 K, lactic acid (6.97 g) added over 1 minute, and stirring continued at 343 K for 70 hours. A white suspension was obtained, and this was diluted to 6% w/w solids for testing.

Example 6

Admixture C14. Sodium Lactatoaluminate(III): Na₁Al₁(Lac)₁

Sodium hydroxide (1.55 g) was dissolved with stirring (340 rpm) in water (10.9 g) maintained at 293 K, lactic acid (3.89 g) added over 2 minutes, and stirring continued for 15 minutes. Aluminum(III) hydroxide (3.69 g) was then added, the temperature raised to 343 K, and stirring continued for 70 hours. A white suspension was obtained, and this was diluted to 6% w/w solids for testing.

Admixtures C15-C20 were similarly prepared using the method of Example 6.

TABLE 12

Preparation and Properties of Admixtures C12-C20

Admixture

Reactants (Mass in g)

Reaction Product

#

Mol Composition

NaOH

Al(OH)₃

Lac

Water

pH

Appearance

C12

Na₁(Lac)₁

2.48

—

6.22

11.3

12.4

Clear Solution

C13

Al₁(Lac)₃

—

2.21

6.97

10.8

3.5

White Suspension

C14

Na₁Al₁(Lac)₁

1.55

3.69

3.89

10.9

9.0

White Suspension

C15

Na₁Al₁(Lac)₂

1.08

2.58

5.43

10.9

8.6

Cloudy Solution

C16

Na₂Al₁(Lac)₃

1.51

1.79

5.67

11.0

8.9

Cloudy Solution

C17

Na₂Al₂(Lac)₃

1.28

3.04

4.79

10.9

7.8

Cloudy Solution

C18

Na₃Al₂(Lac)₃

1.78

2.81

4.44

11.0

10.4

Cloudy Solution

C19

Na₃Al₂(Lac)₄

1.52

2.42

5.08

11.0

9.2

White Suspension

C20

Na₅Al₂(Lac)₆

1.80

1.71

5.41

11.1

9.1

White Suspension

Notes.

Reaction conditions are detailed in Examples 1-3;

NaOH is sodium hydroxide;

Al(OH)₃ is aluminum(III) hydroxide;

Lac is lactic acid;

W is water.

TABLE 13

1:1:3 (w/w) OPC-Fly Ash F-Sand Mortars made with Admixtures C12-C20

Compressive

[Admixture]

Strength

W/C

(% w/w)

Set Time

Hardness (MPa)

(MPa)

#

(w/w)

In Stock

vs Cement

(min)

1 day

1 day

28 day

Water

0.46

—

—

190

48

7.8

18.9

SNC

0.42

—

0.5

160

52

8.1

22.9

SHE

0.41

—

0.5

125

81

13.6

28.7

P20

0.42

—

0.5

110

93

14.0

32.4

C12

0.41

6.0

2.46

185

65

11.8

28.6

C13

0.41

6.0

2.46

135

69

10.2

28.8

C14

0.41

6.0

2.46

80

132

19.3

47.4

C15

0.41

6.0

2.46

75

136

21.4

53.1

C16

0.41

6.0

2.46

65

137

23.7

55.8

C17

0.41

6.0

2.46

85

155

21.3

56.5

C18

0.41

6.0

2.46

57

162

26.5

53.9

C19

0.41

6.0

2.46

52

154

21.4

49.8

C20

0.41

6.0

2.46

47

138

18.1

47.2

Notes:

W/C is the water-to-cement ratio;

Hardness is the Vickers indentation hardness;

SNC is SikaSet NC;

SHE is SikaSet HE;

P20 is Pozzutec 20+.

TABLE 14

2:3 (w/w) Fly Ash C-Sand Mortars made with Admixtures C12-C20

Compressive

[Admixture]

Strength

W/C

(% w/w)

Set Time

Hardness (MPa)

(MPa)

#

(w/w)

In Stock

vs Cement

(min)

1 day

1 day

28 day

Water

0.27

—

—

26

31

4.1

14.3

SNC

0.25

—

0.5

37

44

5.7

16.8

SHE

0.23

—

0.5

42

63

8.9