Production of formate, glycolate, and hydrogen from carbohydrates using violene catalysts

Abstract

The present disclosure relates generally to a process for producing formate, glycolate, and hydrogen as a result of a catalytic reaction of violenes with carbohydrates.

Description

PRODUCTION OF FORMATE, GLYCOLATE., AND HYDROGEN FROM CARBOHYDRATES USING VIOLENE CATALYSTSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 651,249, filed May 23, 2024; the entire contents of this application is hereby incorporated by reference herein.FIELD

[0002] The present disclosure relates generally to a process for producing formate, glycolate, and hydrogen as a result of a catalytic reaction of violenes with carbohydrates.BACKGROUND

[0003] Formic acid (formate in its deprotonated form) has a wide range of uses including in leather tanning, as a decalcifying agent, as a deicing and cleaning agent; as a preservative for foods, as an antibacterial agent, and as an intermediate in chemical manufacturing. Recently, formic acid has been recognized as a potential source for hydrogen (H2) production to enable the H2 economy, because formic acid can transport H2 in a liquid form that is safer and more convenient than transporting compressed H2 gas. Formic acid has limited availability in nature as it is distributed only in certain plants and insects. Formic acid may be industrially synthesized by reacting carbon monoxide (CO) with methanol (CH3OH) under high pressure and temperature to make methyl formate that is hydrolyzed to formic acid. This process is technically involved and expensive, and alternate methods are needed to facilitate low-cost formation of formate from renewable resources for uses outlined above.

[0004] Production of formate from biomass and industrial carbohydrate waste streams would provide a low-cost input for formate production, but catalysts have not been available to transform carbohydrates into formate at low cost and at mild conditions. Additionally, common sources of OH' such as sodium and potassium hydroxide are expensive.

[0005] Initial catalytic experiments to produce electricity from carbohydrate oxidation and convert carbohydrates to CO2 and water, showed that the reaction stopped at formate, which was unexpected and produced 50% of the recovered potential electrical energy with the remaindercontained in formate. In addition, glycolate is also produced from these reactions. Glycolate is used in the cosmetic industry and its value per ton is much more than formate. Therefore, the present disclosure highlights an unmet need for a low-cost input production of formate, glycolate, and hydrogen for a variety of industry applications.BRIEF SUMMARY OF THE DISCLOSURE

[0006] In one aspect, a method for producing formate includes: (1) providing a carbohydrate solution; (2) adjusting the carbohydrate solution pH to between about 11 and about 13; (3) heating the carbohydrate solution to at least 30° Celsius; (4) contacting the carbohydrates solution with a violene catalyst; and (5) producing formate and glycolate products in the presence of oxygen (O2).

[0007] In some embodiments, the method also includes (i) converting the formate into hydrogen gas and carbon dioxide gas; (ii) creating a calcium formate through the addition of a calcium oxide (CaO); (iii) performing a carbon capture resulting in conversion into calcium carbonate; (iv) providing CaO / calcium hydroxide to regulate the pH of the first catalyst. In some embodiments, one or more of steps (i), (ii), (iii), and (iv) are performed prior to a second performance of the steps 1-5.

[0008] In some embodiments, the carbohydrate solution comprises glycerol. In some embodiments, the method also includes converting glycerol into a glyceraldehyde and a dihydroxyacetone (DHA) with a second catalyst; and providing the glyceraldehyde or the dihydroxyacetone or both in the step of providing a carbohydrate.

[0009] In some embodiments, the carbohydrate is selected from: a 12-carbon carbohydrate, a 6- carbon carbohydrate, a 5-carbon carbohydrate, a 4-carbon carbohydrate, a 3-carbon carbohydrate, and mixtures of the same. In some embodiments, the 12-carbon carbohydrate is lactose. In some embodiments, the carbohydrate is derived from fruit juice or potato residues or other carbohydrate waste streams.

[0010] In some embodiments, the method also includes depolymerizing a biomass source comprising a polymeric carbohydrate into monomeric carbohydrates. In some embodiments, the biomass is from a ground-up timber product, further selected from one or more of: sawdust, cellulose, hemi-cellulose, paper pulp, and switchgrass.

[0011] In some embodiments, the method also includes washing manure to obtain the carbohydrate solution and the dried solids both containing useful constituents.

[0012] In some embodiments, the violene catalyst is methyl viologen. In some embodiments, the violene catalyst is homogenous and dispersed in the carbohydrate solution. In some embodiments, the violene catalyst is heterogeneous and fixed to a reactor surface.

[0013] In some embodiments, the chemical base is a hydroxide ion. In some embodiments, the release of a formate and a glycolate is in response to a magnetic separation. In some embodiments, steps 1-5 are performed in an aerobic environment. In some embodiments, steps 1-5 are performed in an anaerobic environment.BRIEF DESCRIPTION OF THE FIGURES

[0014] FIG. 1 illustrates a flowchart representing a process for producing formate, glycolate, and hydrogen as a result of a catalytic reaction of violenes with carbohydrates.

[0015] FIG. 2 illustrates a flowchart of a process for deriving sugars and / or carbohydrates from biomass sources and manure.

[0016] FIG. 3 illustrates a flowchart of a process using biodiesel to produce carbohydrates.

[0017] FIG. 4 illustrates a process for generating hydrogen from the formate, generated as a result of the process / equation demonstrated in FIG. 1.

[0018] FIG. 5 is a possible variation on the process demonstrated in FIG. 4.DETAILED DESCRIPTION OF THE DISCLOSUREDefinitions

[0019] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0020] Units, prefixes, and symbols may be denoted in their SI accepted form. Numeric ranges recited herein are inclusive of the numbers defining the range and include and are supportive ofeach integer within the defined range. Unless otherwise noted, the terms “a” or “an” are to be construed as meaning “at least one of.” The section headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described. All documents, or portions of documents, cited in this application, including but not limited to patents, patent applications, articles, books, and treatises, are hereby expressly incorporated by reference in their entirety for any purpose.

[0021] Throughout this application, the term “about” is used to indicate that a value includes the standard deviation of error for the device of method being employed to determine the value.

[0022] The term “alkyl” as used herein, means a straight or branched hydrocarbon radical or group having at least one carbon atom including but not limited to saturated Ci-Ce such as: methyl, ethyl, 1 -propyl and 2-propyl, 1 -butyl, 2-butyl, 2-methyl-l -propyl, 1,1 -dimethylethyl, 1 -pentyl, 2-pentyl, 3-pentyl, 2-methyl-l-butyl, 3-methyl-l -butyl, 2,2-dimethylpropyl, 1-hexyl, 2-hexyl, 3-hexyl, 2- methyl-1 -pentyl, 3-methyl-l -pentyl, 4-methyl-l -pentyl, 3,3-dimethyl-l-butyl, 3,3-dimethyl-2- butyl, 2-ethyl-l -butyl and the like; C7-C12 such as: 1-heptyl, 2-heptyl, 3-heptyl, 4-heptyl, 2-methyl- 1-hexyl, 4-methyl-l -hexyl, 5-methyl- 1-hexyl, 1-octyl, 2-octyl, 3-octyl, 4-octyl, 6-methyl- 1-heptyl, 5,5-dimethyl-l-hexyl, 2-ethyl-l-hexyl, 2-methyl-l -heptyl, 2-propyl-l -pentyl, 1-nonyl, 2-nonyl, 2- ethyl-2-methyl- 1-hexyl, 4-methyl-l -octyl, 3, 5, 5 -trimethyl- 1-hexyl, 1-decyl, 2-decyl, 4-ethyl-l- octanyl, 2-methyl-l -nonyl, 4-methyl-l -nonyl, 8-methyl-l -nonyl, 1 -undecyl (1 -hendecyl), 2- undecyl, 7-methyl-l-decyl, 1-dodecyl, 5-dodecyl, 2-butyl- 1-octyl, 10-methyl-l-undecyl and the like; C13-C18 such as: 1-tridecyl, 4-methyl-l -dodecyl, 11 -methyl- 1-dodecyl, 1-butyldecyl, 11- methyl-1 -tridecyl, 1-pentadecyl, 1-hexadecyl, 2-hexyl- 1-decyl, 1-heptadecyl, 14-methyl-l- hexadecyl, 15 -methyl -1-hexadecyl, 1-octadecyl, 16-methyl 1-heptadecyl and the like; C19-C32 such as 1-nonadecyl, 2-methyl-l -octadecyl, 10-methyl- 1-octadecyl, 17-methyl- 1-octadecyl, 2,6,10,14-tetramethylpentadecyl, 1-eicosyl (1-arachidinyl, 1-leicosanyl), 18-methyl-l-nonadecyl, 1 -heneicosyl, 19-methyl- 1-eicosyl and 1 -docosyl (1 -behenyl), 1 -tricosyl, 1 -tetracosyl, 1- pentacosyl, 1-hexacosyl, 1-heptacosyl, 1-octacosyl, 1-nonacosyl, 1-triaconstyl, 2,6,10,15,19,23- hexam ethyl- 1 -tetracosyl, 1-hentriaconsyl, 1 -dotriacontyl and the like. Alkyl groups may be unsubstituted or substituted. Alkyl also includes groups having three or more carbons that contain 1 or more sites of unsaturation, that group being known as cycloalkyl groups or radicals.

[0023] The term “cycloalkyl” as used herein means a monocyclic or polycyclic hydrocarbyl group. Illustrative examples of a cycloalkyl group or radical include cyclopropyl, cycloheptyl, cyclooctyl, cyclodecyl, cyclobutyl, adamantyl, norpinanyl, decalinyl, norbornyl, cyclohexyl, and cyclopentyl. Cycloalkyl groups may be unsubstituted or substituted.

[0024] The term “aryl” means an aromatic carbocyclic ring having from 6 to 14 carbon atoms. Illustrative examples of an aryl group or radical include, but are not limited to, phenyl, 1 -naphthyl, 2-naphthyl, 1 -anthryl, 2-antrhyl, 9-anthryl, 1 -phenanthryl, 2-phenanthryl, 3 -phenanthryl, 4- phenanthryl, 5 -phen anthryl, and the like; including fused ring systems with rings that have less than 6 carbons such as 1-acenaphthyl, 3-acenaphthyl, 4-acenaphthyl, 5-acenaphthyl, 1-azulyl, 2- azulyl, 4-azulyl, 5-azulyl, 6-azulyl and the like. Aryl groups may be unsubstituted or substituted with one or more electron donating groups and electron withdrawing groups. The term “aryl” also includes heteroaryls unless otherwise designated.

[0025] The term “heteroaryl” means an unsaturated monocyclic group or radical of 5 or 6 atoms, an unsaturated fused bicyclic group or radical of from 8 to 10 atoms, or an unsaturated fused tricyclic group or radical of from 11 to 14 atoms, the cyclic groups having 1 or 2 heteroatoms independently selected from O, N, or S. Illustrative examples of monocyclic heteroaryl include 2- or 3-thienyl, 2-or 3-furanyl, 1-, 2-, or 3-pyrrolyl, 1-, 2-, or 4-imidazolyl, 1-, 3-, or 4-pyrazolyl, 2-, 4-, or 5-oxazolyl, 2-, 4-, or 5-thiazolyl, 3-, 4-, or 5-isoxazolyl, 3-, 4-, or 5 -isothiazolyl, 2-, 3-, or 4- pyridinyl, 3-or 4-pyridazinyl, 2-or 3-pyrazinyl, and 2-, 4-, or 5-pyrimidinyl. Illustrative examples of bicyclic heteroaryl include 2-, 3-, 4-, 5-, 6-, 7-, or 8-quinolinyl, 1-, 3-, 4-, 5-, 6-, 7-, or 8- isoquinolinyl, 1-, 2-, 3-, 4-, 5-, 6-, or 7-indolyl, 2-, 3-, 4-, 5-, 6-, or 7-benzo[b]thienyl, 2-, 4-, 5-, 6- , or 7-benzofuran, 2-, 4-, 5-, 6-, or 7-benzoxazolyl, 2-, 4-, 5-, 6-, or 7-benzothiazolyl, and 1-, 2-, 3- , 4-, 5-, 6-, or 7-benzimidazolyl. Illustrative examples of tricyclic heteroaryl include 1-, 2-, 3-, or 4-dibenzofuranyl, 1-, 2-, 3-, or 4-dibenzothienyl, and 1-, 2-, 3-, 4-, 5-, 6-, 7-, 8-, or 9-(l, 2,3,4- tetrahydroacridinyl). Heteroaryl groups may be unsubstituted or substituted.

[0026] As used above, a fused bicyclic group or radical is a group wherein two ring systems share two and only two atoms. As used above, a fused tricyclic group or radical is a group wherein three ring systems share four and only four atoms.

[0027] The terms “alkylaryl” and “arylalkyl” as used herein, means an alkyl portion where alkyl is defined above and to include an aryl portion where aryl is defined above. Illustrative examples of alkylaryl include, but are not limited to, toluene, ethylbenzene, propylbenzene, and xylene. Examples of arylalkyl include, but are not limited to benzyl, 2-phenylethyl, 3 -phenylpropyl, 4- phenylethyl, phenylpropyl, 3-methyl-3-phenylpropyl, 1 -naphthylmethyl, 1 -naphthyl ethyl, 3-(l- naphthyl)-propyl, 4-(l-naphthyl)-butyl, 4-(2-naphthyl)-butyl, and 4-phenylheptyl.

[0028] The term “alkylthio” as used herein, means straight or branched chain alkylsulfides of from 1 to 18 (Ci-Cis) carbons with a sulfide group. Illustrative examples include, but are not limited to, methylthio, ethylthio, isopropylthio.

[0029] The term “alkylammonium” as used herein, means radical or group containing a cationic nitrogen (also called a quaternary nitrogen, or tetravalent nitrogen) with one or more alkyl groups as defined above. Examples include, but are not limited to monoalkylammonium, dialkylammonium, trialkylammonium, and tetraalkylammounium. In compounds with an alkylammonium group, a counterion, i.e., an anion, is usually present to offset the positive charge.

[0030] The term “carbohydrate” as used herein, refers to a carbohydrate with a reducing end. “Carbohydrate” means aldoses and ketoses having the general stoichiometric formula Cn(H2O)n, and includes monosaccharides, oligosaccharides and polysaccharides as well as substances derived from monosaccharides by reduction of the carbonyl group (alditols) such as glycerol (glycerin), maltitol, sorbitol, and isomalt, by oxidation of one or more terminal groups to carboxylic acids, or by replacement of one or more hydroxy group(s) by a hydrogen atom, an amino group (amino sugar), thiol group or similar groups. It also includes derivatives of these compounds. By way of example, carbohydrates include sugars such as such as glucose, mannose, galactose, fructose, glyceraldehyde, dihydroxyacetone, erythrose, ribulose, xylulose, sedoheptulose, ribose, deoxyribose, sorbose, glucosamine, and galactosamine; disaccharides such as isomaltose, maltose, cellobiose, lactose, and raffinose; ketoses including trioses such as dihydroxyacetone, tetroses such as erythrulose, pentoses such as ribulose and xylulose, and hexoses such as fructose, psicose, sorbose, tagatose; aldoses including trioses such as glyceraldehyde, tetroses such as erythrose and threose, pentoses such as ribose, arabinose, xylose, and lyxose, and hexoses such as allose, atlrose, glucose, mannose, gulose, idose, galactose, talose; oligosaccharides; polysaccharides such asstarch, glycogen, cellulose, glycoprotein, glycosaminoglycan, and glycolipid. For clarity, in some embodiments, carbohydrates lacking a reducing end are excluded.

[0031] The term “amino sugar” as used herein, means monosaccharides having one hydroxyl group, i.e., alcohol, (commonly but not necessarily in position 2) replaced by an amino group, systematically known as x-deoxy-x-monosaccharides. By way of example, D-glucosamine or 2- amino-2-deoxy-D-glucopyranose is an amino sugar. Other illustrative amino sugars include but are not limited to erythrosamine, threosamine, ribosamine, arabinosamine, xylosamine, lyxosamine, allosamine, altrosamine, glucosamine, mannosamine, idosamine, galactosamine, talosamine, and their derivatives. The amino sugars include both aldose and ketose sugars. Additionally, the amino sugars may be of a straight-chain structure; however, the aldehyde or ketone group of the amino sugar may react with a hydroxyl group on a different carbon atom to form a hemiacetal or hemiketal, in which case there is an oxygen bridge between the two carbon atoms, forming a heterocyclic ring. Amino sugar rings with five and six atoms are called furanose and pyranose forms, respectively and exist in equilibrium with their corresponding straight-chain form. It should be noted that the ring form has one more optically active carbon than the straightchain form, and so has both an a and a form, which interconvert in equilibrium. The term “amino sugar” also means glycosylamines, amino sugars where the nitrogen is substituted with a functional group other than H. Illustrative examples of glycosylamines include N- acetylglucosamine, N-methyl glucosamine.

[0032] The term “violene” and “violene compound” as used herein means a compound of the general formula X — (CR=CR')n— X' , where X and X' are independently a heteroatom such as oxygen, sulfur, or nitrogen independently substituted with H, alkyl, alkylaryl, alkylthio, and alkylammonium; (CR=CR') is an aromatic group or apart of an aromatic group; n is an integer so long as aromaticity of (CR=CR') is maintained; and R and R' are each independently H or a bond. Violene compounds may be characterized by the stability of their radical cations through delocalization throughout a 7i-framework together with a heteroatom.

[0033] Violene compounds include compounds that can become Weitz -type radicals and Wtirster- type radicals. The substituted heteroatom (N-R for example) or heteroatoms in Weitz-type radicals are directly incorporated within the aromatic system, for example viologen compounds includingpyridiniums, conjugated pyridiniums, and bipyridiniums that are defined below. The substituted heteroatom or heteroatoms in Wurster-type radicals are not directly incorporated within the aromatic system, for example N',Nl,N4,N4-tetramethylbenzene-l ,4-diamine and N4,N4,N4',N4'- tetramethylbiphenyl-4,4'-diamine. Additional examples of violene compounds may be found in Hunig, Pure Appl. Chem. 1967, 15, 109-122 and Hunig et al., Top. Curr. Chem. 1980, 92, 1-44, which are hereby incorporated by reference. A violene compound can be viologen or a salt there of. An example of a viologen is l,l’-di(hydrocarbyl)-4, 4’ -bipyridinium salt.

[0034] The term “pyridinium compound” as used herein, as used herein means a cationic form of pyridine by the addition of a substituent to the ring nitrogen, z.e., by alkylation.

[0035] The term “conjugated pyridinium compound” as used herein, means a compound including at least one pyridinium substructure conjugated to an aryl substructure

[0036] The term “bipyridinium compound” as used herein means two pyridinium compounds sharing a common carbon-carbon bond.

[0037] The term “electrode” as used herein, means an electric conductor through which an electric current enters or leaves an electrolytic cell.

[0038] The term “formate” or “formic acid” refers to the chemical H2CO2 and are used interchangeably throughout the disclosure.

[0039] The apparatuses and processes described herein are directed to processes for producing formate, glycolate, and hydrogen as a result of a catalytic reaction of violenes with carbohydrates.

[0040] In one embodiment of the disclosure, reaction 1 is made up of two sub reactions, (la) and (lb), for producing formate as a result of a catalytic reaction of viologens with carbohydrates, using glucose. Vo and Vr are the oxidized and reduced forms of the viologen catalyst, V.C6H12O6 (glucose) + 12 Vo + 18OH’ = 6HCO2 + 12H2O + 12Vr (la)12Vr + 3O2+ 12H+= 12Vo + 6H2O (lb)C6H12O6 (glucose) + 3O2+ 12H++ 18OH- = 6HCO2 + 6H3C2O3- + I8H2O (T)

[0041] Reaction (la) illustrates first the oxidation of glucose by Vo, the oxidized form of the viologen catalyst, to form formate and glycolate and the reduced form of the catalyst, Vr with H2O as a byproduct. Reaction (lb) illustrates the second step of oxidation of Vr using O2 in air and H~ from the solution to convert Vr to H2O and Vo, thereby completing the violene catalytic cycle. The resulting formate and glycolate from reaction (1) and (la) may be used to produce H2 as outlined herein.

[0042] The reaction sequence (la)-(lb) constitutes the “Aerobic Catalytic Cycle” because molecular oxygen (O2) is used for catalyst regeneration. This Aerobic Catalytic Cycle is distinguished from the “Anaerobic Catalytic Cycle” also discussed herein. The Anaerobic Catalytic Cycle includes catalyst regeneration by H+(hydronium, not O2) to form H2. In both processes, formate is formed which can be converted to H2.

[0043] FIG. 1, which illustrates an embodiment of reaction (1), i.e. a flow chart demonstrating a process for producing formate, glycolate, and hydrogen as a result of a catalytic reaction of violenes with carbohydrates.

[0044] In step 100, a carbohydrate may be [is] received as input for the reaction. In some embodiments disclosed herein, a carbohydrate of any source may be used as input. In some embodiments, principal carbohydrates, other carbohydrates (e.g., waste products from fruit juice, potatoes, or any other carbohydrate source), polymers or polymeric sugars. As described in more detail below, biomass (e.g., ground up timber products, sawdust, cellulose, hemi-cellulose, paper pulp, switchgrass), manure, or biodiesel may be used.

[0045] In step 101, a solution containing the carbohydrates described herein may be adjusted to a basic pH. In some embodiments, the solution pH is between 11 and 13. In some embodiments, the carbohydrate solution may be adjusted to a pH of 12. In some embodiments, the carbohydrate solution may be adjusted to a pH of 11. In some embodiments, the carbohydrate solution may be adjusted to a pH of less than 13. In some embodiments, the pH must be limited to pH 11-14. This initial pH adjustment may be required to remove fats, proteins, metal ions and bacterial contamination prior to reaction according to reaction (1) and is accomplished with known caustic reagents (those capable of providing OH'). This initial process is to be distinguished from the use of OH' required as an essential component of reaction (1).

[0046] In step 102 of FIG. 1, in some embodiments (e.g., wherein the carbohydrate solution contains carbohydrates with a higher number of monomeric units n>l, such as lactose, a carbohydrate containing 12 carbon atoms), the carbohydrate may be heated to a temperature of at least 30° degrees Celsius, to induce a more efficient reaction. In some embodiments, the carbohydrate solution may be heated to a temperature of at least 30° degrees Celsius. In some embodiments, the carbohydrate solution is heated to a temperature of at least 35° degrees Celsius. In some embodiments, the carbohydrate solution is heated to a temperature of at least 40° degrees Celsius. In some embodiments, the carbohydrate solution is heated to a temperature of at least 45° degrees Celsius. In some embodiments, the carbohydrate solution is heated to a temperature of at least 50° degrees Celsius. In some embodiments, the carbohydrate solution is heated to a temperature of between 30° and 100° degrees Celsius. In some embodiments, the carbohydrate solution is heated to a temperature of between 40° and 100° degrees Celsius. In some embodiments, the carbohydrate solution is heated to a temperature of between 50° and 100° degrees Celsius.

[0047] In step 103, a violene may be added to the carbohydrate solution as a catalyst. Any viologen as a subset of the violene classification may be used as the catalyst in this reaction. In some embodiments, the violene may be methyl viologen. In some embodiments, the viologen may be dimethyl viologen. In some embodiments the viologen may be monomethyl viologen. In some embodiments, the R group may comprise additional aromatic ring systems connected to the quaternary nitrogen atoms.

[0048] In some embodiments, the catalyst used may be homogenous, so that the catalyst is mobile within a solution. In some embodiments, the catalyst used may be heterogenous, so it is fixed to a substrate or other surface. Non-limiting examples of violenes on metals include violenes on thiol- functionalized gold (e.g. an AU-SH) and violenes on carbon black.

[0049] In step 103 of FIG. 1, a chemical base may be added to maintain a constant ratio with carbohydrate (i.e. maintaining the stoichiometry described in reaction 1). As a non-limiting example, a hydroxide ion may be used as the chemical base or a caustic reagent. Non-limiting examples of substances containing such hydroxide ions include sodium hydroxide and calcium hydroxide.

[0050] It should be noted, however, that an excess of chemical base (e.g., a caustic reagent, such as hydroxide ion) resulting in a pH outside the range of about 11 to about 13 will inactivate the catalyst used in the reaction demonstrated in FIG. 1 reaction (1), which may include, the violenes described above.

[0051] The essential role for OH' may require a balance between preventing an insufficient OH' concentration, which retards the catalytic reaction, and excess OH' concentration, which at higher concentrations (pH >13), can decrease catalytic activity. In some embodiments, to maintain a proper balance, Ca(OH)2 may be used. Ca(OH)2 provides sufficient OH' to maintain the catalytic reaction at a high rate but also assures that a destructive pH is not attained. Ca(OH)2 is a solid that is only slightly soluble and exists in equilibrium with water (Ca(OH)2 = Ca2++ 2OH ), so that as reaction (1) consumes OH', it is replaced by rapid equilibration.

[0052] Another advantageous feature of Ca(OH)2 is that its equilibrium concentration of OH' is such that the pH of the solution never exceeds 12-13, providing a buffered solution so no catalytic destruction can occur.

[0053] In step 104 of FIG. 1, the violene catalyst, such as methyl viologen as a non-limiting example, may break down the carbohydrate to release formate and glycolate (see reaction 2a and 2b, below).

[0054] In addition to formate and glycolate, in some embodiments, an additional product of the reaction demonstrated in reaction (1) may include carbonate. In some embodiments, the carbonate may be recycled. In some embodiments, calcium carbonate may be isolated and heated to produce calcium oxide (CaO) and carbon dioxide (CO2). In some embodiments, CO2 may be captured or used or reused. In some embodiments, the CaO can be reacted with water to form Ca(OH)2 and used as a source of OH' in reaction (1) (see reactions immediately below).CaCO3A = CaO + CO2(2a)CaO + H2O^ Ca(OH)2(2b)CaCO3A + H2O = Ca(OH)2+ CO2(2)

[0055] Regulation of Ch-exposure conditions (for example atmospheric oxygen) can alter the catalytic outcome and produce various percentages of formate to glycolate. High O2 conditions (i.e., where atmospheric oxygen is bubbling through a solution and / or actively being agitated with a stirrer) can change the course of reaction to not only produce formate and glycolate but also useful carboxylic acids. The acid type is dependent on the carbohydrate source undergoing catalytic reaction. For example, when the carbohydrate feed source is glyceraldehyde, the product would be glyceric acid, and when the carbohydrate feed source is glucose, the product would be gluconic acid.Carbohydrate + 1 O2 = Carbohydrate acid

[0056] However, the reaction conditions within the aerobic environment may be adjusted to vary the percentages of formate and glycolate produced. Modifying the reaction conditions can alter the formate to glycolate ratio and produce more glycolate and less formate. Such reaction conditions include temperature, rate or volume of oxygen exposure during carbohydrate oxidation, and catalyst concentration. Higher O2 conditions favor carbohydrate acid formation and less formate and glycolate, producing a new reaction that can be manipulated. As non-limiting examples, altered temperature, pressure, pH, concentrations used of carbohydrates and the selected violene catalyst may all be chosen to preferentially lead to a desirable end product. Passing the formate / glycolate mixture over the correct catalyst may convert the formate to H2 and CO2 which may be released as a gas leaving only glycolate in the solution, providing a unique purification process of glycolate.

[0057] The disclosed embodiments do not require formate formation from an anaerobic, electrical process involving an electrode in a fuel cell. However, as demonstrated herein, formate formation using such an environment is also not precluded from the disclosed embodiments.

[0058] In step 105 in FIG. 1, the formate (and / or glycolate) may be separated from a homogeneous catalyst. In some embodiments, during the homogeneous catalytic reaction of formate and glycolate formation from carbohydrates, the desired formate and glycolate products may be formed in the presence of the homogeneous catalyst. In some embodiments, the formate and glycolates may be separated from the homogeneous catalyst. In some embodiments, this separation step may be necessary to recover products, but importantly, the catalyst may be recovered for reuse.

[0059] In some embodiments, once completed, two separation steps are needed for the homogeneous reaction. The first is separation of the catalyst from the solution. In some embodiments, the separation of formate from glycolate and / or water may be accomplished through distillation. In some embodiments, the separation of formate from glycolate and / or water may be accomplished through precipitation. In some embodiments, the separation of formate from glycolate and / or water may be accomplished through membrane separation. The second separation step may include separation of formate and small but variable amounts of glycolate from the solution.

[0060] In some embodiments, the separation of formate and glycolate from the catalyst may be accomplished using polymeric and immobilization methods (e.g., using immobilized violenes). Viologens are easily polymerized, and polymerized viologens continue to catalyze the formation of formate and glycolate as outlined in reaction (1) but their large size allows separation from the products they catalyzed by membrane separation methods. The products pass through the membrane pores effectively separating the products from the catalyst.

[0061] In some embodiments, if the catalyst is immobilized on a water insoluble support, then separation is accomplished by simply filtering or centrifuging the reaction solution to remove the solid catalytic phase from the liquid phase containing the desired products. In some embodiments, the catalyst may be immobilized on a magnetic substrate such as a metal piece or metal particle. In further embodiments, the immobilized catalyst may be separated by magnetic separation in which the metallic particles are attracted to, and removed by, magnetic action.

[0062] In some embodiments, the catalytic reaction may be performed in an anaerobic environment without oxygen (O2). These conditions are referred to as the Anaerobic Catalytic Cycle as opposed to the Aerobic Catalytic Cycle involving O2, discussed above. The Anaerobic Catalytic Cycle is outlined by reactions (3a)-(3b) herein, using glucose as an example with Vo and Vr being the oxidized and reduced forms of the viologen catalyst. Reaction (3) is the net reaction of reaction (3a) and (3b), showing that glucose can be converted to H2 and formate. Thermodynamic calculations demonstrate that reaction 3 is favorable with a standard free energy change AGo = -254 kJ / mol glucose, and laboratory experiments have demonstrated reaction (3b) using various acids to create acid conditions.C6HI2O6 (glucose) + 12 Vo + 18OH- = 6HCO2+ 12H2O + 12Vr (3 a)12 Vr + 12H+= 12 Vo + 6H2(3b)C6HI2O6(glucose) + 12H++ 18OH’ = 6HCO2+ 6H2+ 12H2O (3)

[0063] In some embodiments, H2CO3 (carbonic acid) formed by dissolving CO2in H2O (H2O + CO2= H2CO3) acts as a source of low cost acid. This process removes CO2from the atmosphere with formation of carbonate salts as a byproduct. In processes using the consumption of atmospheric CO2, another advantage of the disclosed process is removal of atmospheric CO2or reduction of its emission from other processes.

[0064] In some embodiments, reaction (3) may be performed in an anaerobic environment that excludes O2. In these embodiments, the product of the reaction may be approximately 90% formate, and 10% glycolate. These results are only exemplary; in embodiments disclosed herein, the amounts of formate and glycolate may be adjusted according to the environment in which they are formed.

[0065] In some embodiments, the catalyst is not regenerated by O2-oxidation but by oxidation by H+to produce H2. Through this catalytic process formate is used to produce H2still produced in addition to H2.

[0066] In some embodiments, subsequent to completing the process demonstrated in reactions (3 a) and (3b), hydrogen may be created from the formate that results as a product of this process. The H2production that results first provides a path to produce hydrogen that is lower in cost and in larger abundance than typically used methods. In some embodiments, hydrogen produced may then be run or used in hydrogen fuel cells. This process first produces H2from an anaerobic chemical reactor and formate as a coproduct. The formate is then reacted to form from additional H2. The combined processes produce a two-fold increase in H2production.H2 Production

[0067] In some embodiments, the H2production reactions disclosed herein may require a hydrogenation catalyst. A non-limiting example of such a catalyst may include platinum black. Platinum black is one of many hydrogenation catalysts that may be used to convert reducedviologen catalyst to hydrogen. Other examples of hydrogenation catalyst include palladium, nickel, and rhodium.

[0068] Formate, or formic acid, comprises two hydrogens, as well as carbon dioxide (CO2). Thus, formate may be converted to hydrogen (e.g., H2 or H2 gas) + carbon dioxide gas (e.g., CO2 or CO2 gas), as shown in the following equation:H2CO2-^catalyst — >H2+ CO2

[0069] In some embodiments, carbohydrates may be used in reaction (1), resulting in the roughly half-and-half formate / glycolate mixture. In further embodiments, the initial pH of reduced viologen at pH 12 may be reduced to pH near 5. In some embodiments, the proper pH (e.g., 5) may be achieved using acids with formation of hydrogen gas. Examples of suitable acids include nitric acid, hydrochloric acid, acetic acid, carbonic acid. Suitable acids will typically provide a pH condition ranging from 5 to 7. In some embodiments, platinum black may be added to convert reduced viologen and hydrogen ions from acids into hydrogen gas.

[0070] FIG. 4 demonstrates a process for generating hydrogen from the formate, generated as a result of the process / equation reactions demonstrated in FIG. 1 / reaction (1). In step [5] 700, the formate resulting from the processes disclosed herein may be received as an input. In step 401, the pH associated with the violene (e.g., methyl viologen) may be set to approximately 5. In some embodiments, carbon dioxide (CO2) may be bubbled through the viologen solution to lower the pH to the desired level (e.g., 4-5). In step 402, a hydrogenation catalyst may be added. In some embodiments, this hydrogenation catalyst may be platinum black. With the lowered pH of between 4 and 5 in step 401 , the formate may be converted into hydrogen in step 403. In some embodiments, this may be accomplished because a reduced catalyst (Vr) at pH 5 may react with Pt catalysts (e.g., platinum black) to produce oxidized catalyst (Vo) and H2(g). The result from the reaction in step 403 may include hydrogen (H2) and carbon dioxide (CO2).

[0071] FIG. 5 demonstrates a possible variation on the process demonstrated in FIG. 4. In step [6]500, the formate from any of the processes disclosed herein may be used. In step 501, the pH associated with the violene catalyst (e.g., methyl viologen) may be set to between 4 and 8. In some embodiments, the pH is about 5. In some embodiments, carbon dioxide (CO2) may be bubbledthrough the viologen solution to lower the pH to the desired level (e.g., 4-5). In step 502, a hydrogenation catalyst may be added. In some embodiments, this hydrogenation catalyst may be platinum black. Due to the lowered pH of between 4 and 5 in step 501, the formate may be converted to hydrogen. In step 503, hydrogen (H2) will be produced and carbon dioxide evolved (CO2).

[0072] The example embodiments previously described may exist within a practical apparatus, wherein the product solution at pH 5 may be flowed through a tube that has the hydrogenation catalyst fixed in the tube. This tube may include vents where the hydrogen and CO2 are released. Both of these may be captured and separated for hydrogen power use and carbon capture.Aluminum Formate

[0073] The successful production of calcium formate (CaQTCCh ) described herein provides a basis for a low-cost process for formation of aluminum formate (A1(HCO2)3 as outlined by the reaction sequence (4). In some embodiments, aluminum chloride may be added to soluble calcium formate forming insoluble aluminum formate and soluble calcium chloride. In further embodiments, the resulting aluminum formate may be isolated and treated to form a known metalorganic framework. Metal-organic frameworks (MOFs), with their high surface areas, tuneable pore sizes, surface functionality, and structural diversity offer several advantages as the next generation solid adsorbent materials for CO2 capture. The resulting aluminum metal-organic framework exhibits excellent CO2 adsorption characteristics for removal of CO2 from CCh-laden industrial gas streams, providing a low cost process for CO2 capture.3Ca(HCO2)2+ 2A1CF = 2A1(HOCO2)3 +3CaCl2(4)

[0074] In some embodiments, a process for carbon capture may be utilized which, in some embodiments, may be an extension of the process demonstrated in FIG. 1 reaction (1). In these embodiments, the calcium formate, which may be a product of the processes demonstrated herein, may be an input and / or a catalyst in the conversion of carbohydrates to formate, and hence formate to aluminum formate (see equations 5 and 6).H2CO2 -^catalyst — >H2+ CO2(5)nCO2+ A1MOF AlMOF(CO2)n (6)

[0075] As previously discussed, in some embodiments, the calcium hydroxide may regulate the pH of the catalyst. In some embodiments, CaO may be used as an OH' source. In these embodiments, the reactions disclosed herein may create the formate with using CaO as a catalyst, which may create a self-adjusting pH component that protects the viologen catalyst from destruction. In some embodiments, the CaO-formate combination may then be converted to H2 and CO2, as previously described, and the cycle may continue. In some embodiments, the calcium formate resulting from such a reaction may be used as a cement hardener.

[0076] In some embodiments disclosed herein, a carbohydrate of any source may be used as input. In some embodiments, principal carbohydrates may be used. As non-limiting examples, principal carbohydrates may include 12 carbon carbohydrates (e.g., lactose), 6 carbon carbohydrates (e.g., glucose), 5 carbon carbohydrates (e.g., arabinose, xylose), 4 carbon carbohydrates (e g., erythrose), and 3 carbon carbohydrates (e.g., dihydroxyacetone).

[0077] In some embodiments, other carbohydrates may be received as input. As non-limiting examples, carbohydrate sources in these embodiments may include waste products from fruit juice, potatoes, or any other carbohydrate source (e.g., sugar beet waste sugar).

[0078] In some embodiments, polymers or polymeric sugars may be used as the carbohydrates in reaction (1) herein.

[0079] In some embodiments, a cobalt catalyst may be used to break down polymeric carbohydrates. For exemplary catalysts see US 9,809,613 incorporated herein by reference.

[0080] In some embodiments, such as those disclosed herein that break up biomass into polymeric carbohydrates, a cobalt catalyst may also be utilized as a preliminary step, and / or in the steps of FIG. 1 / reaction (1), as needed. (See US 9,809,613, incorporated herein by reference.)

[0081] In some embodiments, a cobalt catalyst, as described above, may be used to break up biomass into the carbohydrates used in reaction (1). As non-limiting examples, such biomass may include ground up timber products, sawdust, cellulose, hemi-cellulose, paper pulp, switchgrass, etc.

[0082] In some embodiments, manure may be used as a carbohydrate resource described above. FIG. 2 demonstrates a process for deriving sugars and / or carbohydrates from manure. In step 300, the manure may be washed with caustic solution (a solution containing OH ) to remove proteins, fats, metal ions, and catalyst inhibitors. In some embodiments, the wash may contain sugars initially present or that were produced during the washing process in step [3]200. In step 201, these sugars may be collected for example by reverse osmosis. In some embodiments, the sugars can be used directly to form formate when the sugars are otherwise free of contaminants. In step 202, sugars and / or carbohydrates may be derived from the manure directly, providing two separate sources of carbohydrates: those derived from the solid manure directly, and from the sugars collected from the wash.

[0083] In some embodiments, the sugar fraction may be treated to remove possible organic inhibitors, adjusted to pH 12 to remove metal ion contamination, and filtered to remove particulate matter. To use the polymeric carbohydrate components of manure (mainly cellulose, hemicellulose and lignin) they may be first converted to monomeric (one), dimeric (two), or lower forms of polymerization (<five) that readily and efficiently undergo catalytic reaction. In some embodiments, if high efficiency is not required, the washed manure fraction with high polymerization (>five) may undergo partial reaction with a lower overall efficiency.

[0084] In step 203, the resulting carbohydrates, both directly from the manure, or collected from the wash, may then be used as the carbohydrate in step 100 of FIG. 1 / reaction (1) described above.Biodiesel

[0085] FIG. 3 demonstrates another source of carbohydrates that may be used in the disclosed embodiments. Specifically, the carbohydrates, and in turn, the formate and glycolate produced by these carbohydrates, may be derived from the manufacture of biodiesel. In some embodiments, demonstrated in step [4]300, manufacture of biodiesel may produce glycerol as a product (possibly a waste product) from a biodiesel reaction (possibly making up 20-30% of the overall input for biodiesel).

[0086] In some embodiments, demonstrated in step 301, a process may be used to convert glycerol to di hydroxy acetone (DHA) and glyceraldehyde. (See D. Voss, R. Dietrich, M. Stuckart J. Albert.Switchable catalytic polyoxometalate-based systems for biomass conversion to carboxylic acids. ACS omega.5, 2020,19082-19091; see also Mishra R. Jain SR. Kumar A. Microbial production of diydroxyacetone. Biotechnol Adv 2008:26:293-303;Chin liu, Makoto Hirohara, Tatsuhiro Maekawa, Ryongsok Chang, Tomohiro Hayashi, Chia-Yang Chiang. Selective electro-oxidation of glycerol to dihydroxyacetone by a non-precious electrocatalyst-CuO. Applied Catalysis B: Environmental 265 (2020) 118543.) In step 402, the resulting DHA or glyceraldehyde may then be used as the carbohydrate in step 100 of FIG. 1 and catalytically converted to formate in a process similar to the above in reaction (1).

[0087] Additionally, evidence of conversion of DHA and other carbohydrates into various valuable acids has also been observed using the reaction demonstrated in reaction (1). (See D. Voss, R. Dietrich, M. Stuckart J. Albert. Switchable catalytic polyoxometalate-based systems for biomass conversion to carboxylic acids. ACS omega.5, 2020,19082-19091.) Although the conversion of DHA and other carbohydrates to acids offers an additional useful products, the formation of these other acid products terminates further reaction of DHA and carbohydrates from forming formate.

[0088] In some embodiments, hydrogen and formate generated from waste sugars may be taken from milk products, as well as any of the carbohydrates disclosed as non-limiting examples herein, and these sugars and / or carbohydrates may be converted into hydrogen. Specifically, in some embodiments, the synthesis of hydrogen production from formate may begin with the steps outlined in the embodiments associated with FIG. 1 / reaction (1).Violenes

[0089] Non-limiting examples of the R groups present on viologens may include: dimethyl viologens; monomethyl viologens, which react more slowly than dimethyl viologens, but monomethyl viologens provide a better overall potential energy recovery; polymers of viologen, or polymeric viologens.

[0090] Other viologen variations may include: polymeric and dendrimeric viologen species; immobilized viologens on electrodes, which are connected to electrical apparatuses; viologensfrom nanoparticles; viologens on carbon black and other carbon substrates; and all of the viologens that oxidize carbohydrates.

[0091] In some embodiments, the catalyst used may be heterogenous, so it is fixed to a surface. Non-limiting examples of violenes on metals including alkyl violenes functionalized with a thiol (-SH) group. The thiol group can bind to gold, silver, nickel, copper, or other transition metal surfaces. Violenes can also be connected to carbon substrates through strong carbon-carbon bonds.

[0092] In some embodiments, the catalyst may be immobilized on a magnetic substrate such as a metal piece, metal particle, metal beads and nanoparticles of metal.

[0093] In some embodiments, metallic gold (Au) is reacted with an alkyl thiol (R-SH) to form thiol functionalized gold surface (Au-SH). In some embodiments, metallic nickel (Ni) is reacted with alkyl thiol to form thiol functionalized nickel surface.Statements

[0094] 1. A method for producing formate and glycolate comprising: a. providing a carbohydrate solution; b. adjusting the carbohydrate solution pH to between about 11 and about 13; c. heating the carbohydrate solution to at least 30° Celsius; d. contacting the carbohydrates solution with a violene catalyst; and e. producing formate and glycolate products.

[0095] 2. The method of statement 1, further comprising:(i) converting the formate into hydrogen gas and carbon dioxide gas;(ii) creating a calcium carbonate through the addition of a calcium;(iii) performing a carbon capture resulting in conversion into calcium hydroxide or calcium carbonate;(iv) providing the calcium hydroxide to regulate the pH of the first catalyst, prior to a second performance of the steps of statement 1.

[0096] 3. The method of any one of statements 1 and 2, wherein the carbohydrates is glycerol, further comprising: converting glycerol into a glyceraldehyde and di hydroxy acetone (DHA) with second catalyst; and providing the glyceraldehyde or the dihydroxyacetone or both in the providing a carbohydrate step.

[0097] 4. The method of any one of statements 1-3, wherein the carbohydrate is selected from: a 12-carbon carbohydrate, a 6-carbon carbohydrate, a 5-carbon carbohydrate, a 4-carbon carbohydrate, or a 3 -carbon carbohydrate.

[0098] 5. The method of statement 4, wherein the 12-carbon carbohydrate is lactose.

[0099] 6 The method of any one of statements 1-5, wherein the carbohydrate is derived from a fruit juice or a potato.

[0100] 7 The method of any one statements 1-6, further comprising: depolymerizing a biomass comprising a polymeric carbohydrate into monomeric carbohydrates.

[0101] 8. The method of claim 7, wherein the biomass is from a ground-up timber product, further selected from one or more of: sawdust, cellulose, hemi-cellulose, paper pulp, and switchgrass.

[0102] 9. The method of claim 1, further comprising: washing manure to obtain the carbohydrate solution and a solid fraction containing complex polycarbohydrate components.

[0103] 10. The method of any one of statements 1-9, wherein the violene catalyst is methyl viologen.

[0104] 11. The method of any one of statements 1-10, wherein the violene catalyst is homogenous and dispersed in the carbohydrate solution.

[0105] 12. The method of any one of statements 1-10, wherein the violene catalyst is heterogeneous and fixed to a reactor surface.

[0106] 13. The method of any one of statements 1 -12, wherein the chemical base is a hydroxide ion or CaO

[0107] 14. The method of any one of statements 1-13, wherein the release of a formate and a glycolate is in response to a magnetic separation.

[0108] 15. The method of any one of statements 1-14, wherein the steps of claim 1 are performed in an aerobic environment.

[0109] 16. The method of any one of statements 1-14, wherein the steps of claim 1 are performed in an anaerobic environment.

[0110] The present disclosure enables one of skill in the relevant art to make and use the inventions provided herein in accordance with multiple and varied embodiments. Various alterations, modifications, and improvements of the present disclosure that readily occur to those skilled in the art, including certain alterations, modifications, substitutions, and improvements are also part of this disclosure. Accordingly, the foregoing descriptions are by way of example to illustrate the discoveries provided herein. Furthermore, the foregoing Description and Examples are exemplary of the present invention and not limiting thereof. The scope of the invention is therefore set out in the appended claims.

[0111] Although specific embodiments of the present disclosure are herein illustrated and described in detail, the disclosure is not limited thereto. The above detailed descriptions are provided as exemplary of the present disclosure and should not be construed as constituting any limitation of the disclosure. Modifications will be obvious to those skilled in the art, and all modifications that do not depart from the spirit of the disclosure are intended to be included within the scope of the appended claims.

Claims

1. A method for producing formate and glycolate comprising:(1) providing a carbohydrate solution;(2) adjusting the carbohydrate solution pH to between about 11 and about 13;(3) heating the carbohydrate solution to at least 30° Celsius;(4) contacting the carbohydrates solution with a violene catalyst; and(5) producing formate and glycolate products.

2. The method of claim 1, further comprising:(i) converting the formate into hydrogen gas and carbon dioxide gas;(ii) creating a calcium carbonate through the addition of a calcium;(iii) performing a carbon capture resulting in conversion into calcium hydroxide or calcium carbonate;(iv) providing the calcium hydroxide to regulate the pH of the first catalyst, prior to a second performance of the steps of claim 1.

3. The method of claim 1, wherein the carbohydrates is glycerol, and the method further comprises: converting glycerol into a glyceraldehyde and dihydroxyacetone (DHA) with second catalyst; and providing the glyceraldehyde or the dihydroxyacetone or both in the providing a carbohydrate step.

4. The method of claim 1, wherein the carbohydrate is selected from: a 12-carbon carbohydrate, a 6-carbon carbohydrate, a 5-carbon carbohydrate, a 4-carbon carbohydrate, or a 3- carbon carbohydrate.

5. The method of claim 4, wherein the 12-carbon carbohydrate is lactose.

6. The method of claim 1, wherein the carbohydrate is derived from a fruit juice or a potato.

7. The method of any claim 1, further comprising: depolymerizing a biomass comprising a polymeric carbohydrate into monomeric carbohydrates.

8. The method of claim 7, wherein the biomass is from a ground-up timber product, further selected from one or more of: sawdust, cellulose, hemi-cellulose, paper pulp, and switchgrass.

9. The method of claim 1, further comprising: washing manure to obtain the carbohydrate solution and a solid fraction containing complex polycarbohydrate components.

10. The method of claim 1, wherein the violene catalyst is methyl viologen.

11. The method of any claim 1, wherein the violene catalyst is homogenous and dispersed in the carbohydrate solution.

12. The method of claim 1, wherein the violene catalyst is heterogeneous and fixed to a reactor surface.

13. The method of claim 1, wherein the chemical base is a hydroxide ion or CaO.

14. The method of claim 1, wherein the release of a formate and a glycolate is in response to a magnetic separation.

15. The method of claim 1, wherein the steps of claim 1 are performed in an aerobic environment.

16. The method of claim 1, wherein the steps of claim 1 are performed in an anaerobic environment.

17. The method of claim 2, wherein the carbohydrates it glycerol, and the method further comprises: converting glycerol into a glyceraldehyde and dihydroxyacetone (DHA) with second catalyst; and providing the glyceraldehyde or the dihydroxyacetone or both in the providing a carbohydrate step.

18. The method of any claim 17, wherein the carbohydrate is selected from: a 12-carbon carbohydrate, a 6-carbon carbohydrate, a 5-carbon carbohydrate, a 4-carbon carbohydrate, or a 3- carbon carbohydrate.

19. The method of claim 18, wherein the 12-carbon carbohydrate is lactose.

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