Catalytic oxidation of ethanol

Abstract

Process in which ethanol, oxygen, at least one catalyst, optionally at least one co-catalyst, optionally at least one additive, and optionally at least one solvent are contacted in a reaction zone, optionally under light irradiation, to produce acetic acid and to produce ethyl acetate. The process provides an efficient conversion of ethanol to acetic acid and to ethyl acetate, and in particular provides efficient processes for the conversion of bioethanol to bio-acetic acid and for the conversion of bioethanol to bio-ethyl acetate.

Description

[0001] PCT Application based on U.S. Provisional Application 63 / 537,919 CATALYTIC OXIDATION OF ETHANOL REFERENCE TO PRIOR APPLICATIONS This application claims priority to U.S. provisional application 63 / 537,919 filed September 12, 2023, incorporated herein by reference as if fully written out. FIELD OF THE INVENTION Processes for the oxidation of ethanol are typically plagued by low yields, low selectivity, etc., often due to over-oxidation to carbon dioxide. However, because ethanol oxidation products like acetic acid and ethyl acetate can be used for example in the production of vinyl acetate monomer (VAM), acetic anhydride, acetate esters, as a solvent for purified terephthalic acid production, etc.(acetic acid), and used as a solvent, a diluent, in glues, nail polish removers, etc. (ethyl acetate), and because ethanol can be sourced in several ways, including as a renewable resource via fermentation (bioethanol), there is strong interest in the development of an efficient process for the oxidation of ethanol, particularly a process producing acetic acid and / or ethyl acetate in good yields and with good selectivity. This is especially true in view of the versatility of VAM, which can be used in downstream applications such as paint, adhesives, etc. and which can be co-polymerized with ethylene to produce poly(ethylene-vinyl acetate) or PEVA, etc. For clarity, the terms “invention,” “the invention,” “the present invention,” and the like as used herein refer only to the particular embodiment(s) and / or aspect(s) of the inventors’ contributions immediately mentioned. They are not in any way broadly limiting of the inventors’ overall contributions to the art as described herein, taken as a whole, nor are they generally or specifically limiting with regard to the several individual advances in the art described herein. SUMMARY OF THE INVENTION The inventors have discovered a versatile process for the oxidation of ethanol that can provide acetic acid and ethyl acetate in excellent yields and with high selectivities. The process is a catalytic process in which ethanol, oxygen, at least one catalyst, optionally at least one co- catalyst, optionally at least one additive, and optionally at least one solvent, are contacted in a PCT Application based on U.S. Provisional Application 63 / 537,919 reaction zone, optionally under light irradiation, to produce at least one of, and typically both of, acetic acid and ethyl acetate. As will be described in more detail herein, the yields, selectivity, etc., for acetic acid and ethyl acetate vary depending on a variety of factors including starting material, solvent use, solvent identity, catalyst identity, co-catalyst identity, additive identity, whether light irradiation is used, process conditions, etc. Generally, the production of acetic acid is optimized in the presence of solvent and the production of ethyl acetate is optimized in the absence of solvent or in the presence of acetic acid as solvent. The catalyst is a preferably carbon-hydrogen (C-H) activation catalyst, preferably a sp3 hybridized carbon-hydrogen (C-H) activation catalyst. More than one can be used. Typical examples include at least one of tetra-n-butylammonium decatungstate, sodium decatungstate, cerium (III) chloride, cerium (IV) sulfate, [NEt4]2[CeIVCl6], cerium ammonium nitrate, bis(acetylacetonato)dioxomolybdenum(VI), copper(II) chloride, benzophenone and its derivatives such as 2-trifluoromethylbenzophenone, xanthone and thioxanthone, and peroxides such as hydrogen peroxide, benzoyl peroxide, and di-tert-butyl peroxide. The optional co-catalyst is preferably one that promotes propagation of chain oxidation reactions. More than one can be used. Typical examples include at least one of N- hydroxyphthalimide and derivatives thereof such as N-hydroxysuccinimide. The optional additive is preferably one that promotes decomposition of peroxides enabling chain oxidation reactions. More than one can be used. Typical examples include at least one of cobalt (II) acetate and other cobalt, manganese, and zirconium complexes such as cobalt(II) acetylacetonate, manganese(III) acetylacetonate, and zirconium acetate. The optional irradiation, when used, is preferably provided by a light-emitting diode (LED). Wavelengths of irradiation preferably include wavelengths of 250nm to 450nm. More than one wavelength can be used. In various preferred embodiments the process achieves ethanol conversions of up to 99+%, provides a selectivity of 80+% for acetic acid, provides a selectivity of 20+% for ethyl acetate, and can provide space-time yields of up to at least 1,500gL-1h-1. In certain embodiments the process is cost-competitive with the Cativa process that uses methanol and CO feedstocks. PCT Application based on U.S. Provisional Application 63 / 537,919 In general, the process provides an efficient process for the conversion of ethanol to acetic acid and to ethyl acetate, and in particular provides efficient processes for the conversion of bioethanol to bio-acetic acid and for the conversion of bioethanol to bio-ethyl acetate. DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process in which ethanol, oxygen, at least one catalyst, optionally at least one co-catalyst, optionally at least one additive, and optionally at least one solvent are contacted in a reaction zone, optionally under light irradiation, to produce acetic acid and to produce ethyl acetate. As noted above, the invention process is generally optimized for the production of acetic acid when the reaction is conducted in the presence of solvent whereas the production of ethyl acetate is generally optimized in the absence of solvent or when acetic acid is used as solvent. The acetic acid produced with the invention process can be further reacted to produce VAM, acetic anhydride, acetate esters, and other value-added products, and is especially attractive when a bio-based starting material (e.g., ethanol) is used. The ethyl acetate produced with the invention process can be used as a solvent, a diluent, in glues, nail polish removers, etc. and is similarly especially attractive when a bio-based starting material (e.g., ethanol) is used. Descriptions of processes for the oxidization of ethanol and other substrates, and descriptions of other oxidations and catalysts, some aspects of which are useful herein, are found, for example, in U.S.5,840,971, U.S.8,471,060, US 2012 / 0245382, US 2023 / 0202959, U.S.10,703,700, Ishii et al., Alkane Oxidation with Molecular Oxygen Using a New Efficient Catalytic System: N- Hydroxyphthalimide (NHPI) Combined with Co(acac)n (n=2 or 3), J. Org. Chem.1996,61,4520- 4526, Ishii et al., Efficient Oxidation of Alcohols to Carbonyl Compounds with Molecular Oxygen Catalyzed by N-Hydroxyphthalimide Combined with a Co Species, J. Org. Chem. 2000,65,6502-6507, Hu et al., NHPI / tert-butyl nitrite: A highly efficient metal-free catalytic system for aerobic oxidation of alcohols to carbonyl compounds using molecular oxygen as the terminal oxidant, Catalysis Communications 83 (2016) 82–87, Christensen et al., Formation of Acetic Acid by Aqueous-Phase Oxidation of Ethanol with Air in the Presence of a Heterogeneous Gold Catalyst, Mostrou et al., Catalytic oxidation of aqueous bioethanol: an efficient upgrade from batch to flow, React. Chem. Eng., 2018,3, 781–789, Tzirakis et al., Decatungstate as an efficient photocatalyst in organic chemistry, Chem. Soc. Rev.,2009,38, 2609–2621, Laudadio et al., Selective C(sp3)-H Aerobic Oxidation Enabled by Decatungstate Photocatalysis in Flow, PCT Application based on U.S. Provisional Application 63 / 537,919 Angew. Chem.Int.Ed.2018,57, 4078–4082, and Dagle et al., Ethanol as a Renewable Building Block for Fuels and Chemicals, Ind. Eng. Chem. Res.2020, 59, 4843−4853, all of which are individually incorporated herein by reference as if fully written out. As used herein the articles “a,” “an” and “the” preceding an element or component of the invention are intended to be nonrestrictive regarding the number of instances (i.e., occurrences) of the element or component. Therefore “a,” “an” and “the” should be understood to mean one or more, and the singular word form of the element or component also includes the plural unless the number is obviously meant to be singular. As used herein the terms “comprise(s),” “include(s),” “having,” “has,” “can,” “contain(s),” and variants thereof are intended to be open-ended transitional phrases, terms, or words that do not preclude the possibility of additional features, components, acts, steps, groups, structures, etc. As used herein, including within the claims, the term “comprising” is intended to include embodiments encompassed by the terms “consisting essentially of” and “consisting of.” Similarly, the term “consisting essentially of” is intended to include embodiments encompassed by the term “consisting of.” As used herein, when an amount, concentration, or other value or parameter is given as a range, or as a list of values, this is to be understood as including endpoints, as specifically disclosing all ranges formed from any pair of any upper and lower values, and as specifically disclosing all integers and fractions within the range, regardless of whether ranges, all integers, and fractions are separately disclosed. For example, both a range of 3-10 and a listing of values such as 3, 6, 7, 9, and 10 specifically disclose and include ranges such as 5-7 and 6-9 as well as individual values such as 3, 4.7, 8.3, and 10. Recited numerical limitations include an appropriate degree of precision based on the number of significant places used; for example, “up to 5.0” can be read as setting a lower absolute ceiling than “up to 5.” As used herein, when naming substances that can exist in multiple enantiomeric forms, reference to the name of the substance without an enantiomeric designation, such as (d) or (l), refers herein to the genus of substances including the (d) form, the (l) form and the racemic mixture (e.g., d,l), unless otherwise specified. Similarly, generic reference to compounds that can exist in two or PCT Application based on U.S. Provisional Application 63 / 537,919 more polymorphs is understood to refer to the genus consisting of each individual polymorph species and any combinations or mixtures thereof. Any published article, reference, brochure, written material, etc., including patents and published patent applications, identified herein are incorporated herein by reference as if written out. In a preferred embodiment the invention process is a liquid / gas phase oxidation process. For example, liquid ethanol, a liquid phase catalyst composition (e.g., a catalyst composition dissolved in a solvent), and oxygen gas are contacted in a reaction zone. In the liquid / gas phase oxidation process some of the ethanol can be in gas form but some of the ethanol is present in liquid form. Also, in the liquid / gas phase oxidation process, some of the catalyst composition can be in gas form, but some of the catalyst composition is present in liquid form. In another preferred embodiment the process is a solid / liquid / gas phase oxidation process. Liquid ethanol, a catalyst composition in solid form, and oxygen gas are contacted in a reaction zone. In the solid / liquid / gas phase oxidation process some of the catalyst composition can be liquid, be dissolved in solvent, etc., but some of the catalyst composition is present in solid form. In addition, in the solid / liquid / gas phase oxidation process some of the ethanol can be in gas form but some of the ethanol is present in liquid form. In another preferred embodiment the process is a gas phase selective oxidation process. Ethanol, a catalyst composition, and oxygen, all in the gas phase, are contacted in a reaction zone. The ethanol used in the invention process is not limited. Any source of ethanol is acceptable, petrochemical or other, with bioethanol being one preferred source of ethanol. Bioethanol produced from corn or sugarcane is especially preferred, but any source can be used including sugar, starch, cellulose, waste gas, etc. The ethanol, regardless of source, can be anhydrous ethanol (200 proof ethanol), or can be a mixture of ethanol and water, preferably not denatured, such as 10-99%, 20-99%, 30-99%, 40-99%, 50-99%, 60-99%, 70-99%, 80-99%, and 90-99% ethanol / water mixtures (20-198 proof), etc., for example 60% / 120 proof - 90% / 180 proof, or higher, including preferably 95% / 190 proof. The oxygen used in the invention process is not limited, and it may be added to / present in the reaction zone in mixture with one or more other gases. Pure oxygen and mixtures of oxygen with non-reactive gases such as nitrogen, carbon dioxide, any one or more of the noble gasses PCT Application based on U.S. Provisional Application 63 / 537,919 (helium, neon, argon, krypton, xenon and radon), etc., are preferred, but other sources of oxygen, such as air, can be used. Where mixtures are used the mixture preferably contains at least 5% v / v oxygen, including 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and more. However, oxygen mixtures containing from less than 1% to 99+% oxygen can be used, preferably in mixture with one other gas, preferably nitrogen. For all of the catalysts, co-catalysts, additives, etc. described herein that are transition metal complexes, these complexes can be used in any form, including hydrate form, in a form coordinated to a solvent molecule (e.g., acetonitrile), etc. The catalyst is a preferably carbon-hydrogen (C-H) activation catalyst, preferably a sp3 hybridized carbon-hydrogen (C-H) activation catalyst. More than one can be used. Typical examples include at least one tungstate, cerium, or molybdenum compound or complex, such as at least one of tetra-n-butylammonium decatungstate, sodium decatungstate, cerium (III) chloride, cerium (IV) sulfate, [NEt4]2[CeIVCl6], cerium ammonium nitrate, bis(acetylacetonato)dioxomolybdenum(VI), copper(II) chloride, benzophenone and its derivatives such as 2-trifluoromethylbenzophenone, xanthone and thioxanthone, and peroxides such as hydrogen peroxide, benzoyl peroxide, and di-tert-butyl peroxide. Preferred catalysts include TBADT = Tetra-n-butylammonium decatungstate (e.g., CAS: 68109-03-5); NaDT = Sodium decatungstate (e.g., CAS: 126752-51-0); CeCl3= cerium(III) chloride (e.g., CAS: 7790- 86-5); Na2WO42H2O = sodium tungstate dihydrate, MoO2(acac)2 = bis(acetylacetonato)dioxomolybdenum(VI), and 2-CF3BP = 2-trifluoromethylbenzophenone. The optional co-catalyst may include at least one of N-hydroxyphthalimide, N- hydroxysuccinimide, 2,6-Dihydroxypyrrolo[3,4-f]isoindole-1,3,5,7(2H,6H)-tetraone, N- Hydroxymaleimide, 2-hydroxy-1H-benzo[de]isoquinoline-1,3(2H)-dione, and 2-hydroxy-1H- benzo[f]isoindole-1,3(2H)-dione. When used, preferred co-catalysts include NHPI and derivatives of NHPI such as1,3-dioxoisoindolin-2-yl acetate and N- hydroxytetrachloropthalimide. NHPI = N-Hydroxyphthalimide (e.g., CAS: 524-38-9) The optional additive may include at least one of cobalt (II) acetate and other cobalt and manganese complexes such as Co(acac)2, Co(acac)3,Mn(acac)3, Cu(OAc)2, Fe(acac)3, etc. When used, Co(OAc)2 is a preferred additive (Cobalt(II) acetate, e.g., CAS: 71-48-7). PCT Application based on U.S. Provisional Application 63 / 537,919 The optional solvent may include at least one of ethanol, methanol, propanol, isopropanol, acetonitrile, acetone, water, ethyl acetate, acetic acid, benzene, cyclohexane, chloroform, methylene chloride, hexane, toluene, xylene, carbon tetrachloride, ethyl acetate, dichloroethane, dimethyl carbonate, DMF, benzonitrile, anisole, methyl acetate, methyl benzoate, benzonitrile, etc. When used, acetic acid and ethyl acetate are preferred solvents. Generally, the invention process is optimized for the production of acetic acid when the reaction is conducted in the presence of solvent, whereas the production of ethyl acetate is optimized when the reaction is conducted in the absence of solvent or when acetic acid is used as solvent. When used, preferably the solvent is nonreactive. The solvent may be deuterated if desired. When one or more solvents are used the amount of ethanol reactant present in the reaction zone is not limited, but is preferably present in the reaction zone an amount of at least 5 vol% ethanol / solvent, more preferably 10-95% v / v ethanol / solvent including 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, and 90% v / v ethanol / solvent. The amount of catalyst used in the invention process is not limited. Based on total volume of ethanol and optional solvent, the catalyst can be used in amounts of, e.g., 0.01 – 500 mM, including 0.05, 0.1, 0.5, 1, 3, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, and 400 mM for each catalyst species used. The amount of optional co-catalyst used in the invention process is not limited. Based on total volume of ethanol and optional solvent, the co-catalyst can be used in amounts of, e.g., 0.01 – 1000 mM, including 0.05, 0.1, 0.5, 1, 3, 5, 10, 50, 100, 200, 300, 400, 500, 600, 700, 800, and 900 mM for each co-catalyst species used. The amount of optional additive used in the invention process is not limited. Based on total volume of ethanol and optional solvent, the additive can be used in amounts of, e.g., 0.01 – 500 mM, including 0.05, 0.1, 0.5, 1, 3, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, and 400 mM for each additive species used. The catalyst used in the present invention process may be commercially available and can generally prepared by one of ordinary skill in the art in view of the description in this application. When used in combination with the optional co-catalyst and / or in combination with the optional additive the combination may be prepared separately before introduction to the PCT Application based on U.S. Provisional Application 63 / 537,919 reaction zone, or the catalyst(s), the optional co-catalyst(s), and the optional additive(s) can be added to the reaction zone individually or in any combination. The invention process can be accomplished in any manner that brings together the ethanol, the oxygen, the at least one catalyst, the at least one optional co-catalyst, the at least one optional additive, and the at least one optional solvent in a reaction zone under conditions (time, temperature, pressure, optionally under light irradiation, etc.) sufficient to produce acetic acid and / or ethyl acetate from the ethanol. Examples include batch, fed batch, and continuous processes. In a preferred embodiment a fed-batch process is used where, for example, the pressure of an oxygen-containing gas is maintained relatively constant throughout reaction. In a preferred embodiment the invention process is not conducted in the presence of solvent. In certain embodiments the present invention process can be conducted while illuminating the reaction zone with light, preferably light having a wavelength range of 250 – 450 nm, more preferably 300-400 nm, most preferably 340-370 nm such as 365 nm. Generally, light can be used in any manner, for example by varying exposure times, and at various doses, wavelengths, and irradiance levels, as determined by one of ordinary skill in the art in consideration of the particular catalyst, etc., used and apparatus used, in view of this disclosure. Generally, light irradiation reduces the reaction induction period, resulting in faster reaction initiation. Several wavelengths of light can be used together and / or serially, if desired. In certain embodiments the invention process can be conducted under a pressure of 1-100 bar (gauge) including 2, 3, 4, 5, 6, 7, 8, 10, 20, 30, 40, 50, 60, 70, 80, and 90 bar, and a temperature of, e.g., room temperature (25oC) and above, such as 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 220, 240, 250, 260, 280, and 300oC. In certain embodiments a preferred temperature is 80-150oC. While not limited, in certain embodiments the invention process can be conducted for a time of from 15 minutes to four or more hours (batch and fed batch), with times of approximately 1-2 hours providing good results. Generally, the greater the amount of ethanol present the longer the reaction takes. In a preferred embodiment the invention reaction is conducted under fed batch conditions, where oxygen is continuously supplied and the desired pressure (e.g., 5-5,000 psig, including 25, 75 PCT Application based on U.S. Provisional Application 63 / 537,919 100, 150, 300, 500, 700, 1000, 2000, 3000, 4000, and 4500 psig) is maintained. For example, the ethanol, optional solvent, and catalyst composition are placed in a vessel and the air inside the vessel is purged and replaced with oxygen. The system is then pressurized to the desired pressure with gas comprising oxygen, the temperature of the system is raised to the desired temperature (e.g., 40-250oC; 120oC), and the vessel is irradiated with, e.g., a 250-450 nm; 365nm LED. After a given reaction time (e.g., 0.25 – 3 hours; 1 hour), the light is turned off, and the reaction mixture is allowed to cool to room temperature. The contacting step(s) of the invention process may be practiced in any manner and at any scale, including laboratory scale experiments through full scale commercial operations. The process may be operated in any way, including batch, fed-batch, continuous, and semi-continuous mode. The contacting step(s) can take place in any of various ways. The order of addition of the reaction materials – ethanol, catalyst, optional co-catalyst, optional additive, oxygen, optional solvent, etc., is not critical. For example, the materials can be added individually, or two or more materials may be combined or mixed before being combined or mixed with other materials. Preferably, the oxygen is added last. Conventional, liquid phase oxidation reactors as known in the art may be used to practice the invention. Examples include vessels, which may have one or more mechanical agitators, continuous stirred tank reactors, flow reactors and various bubble column reactors such as those described in U.S. Pat. No.7,692,036. It is also known to design, operate, and control such reactors and the oxidation reaction for the oxidation conditions employed including, e.g., the temperature, pressure, liquid and gas volumes, and corrosive nature of the liquid and gas phases where applicable. See, e.g., U.S. Pat. Nos.7,692,036 and 6,137,001. In preferred embodiments the process achieves ethanol conversions of at least 25, 30, 40, 50, 60, 70, 80, 85, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, and 99+%. In preferred embodiments the invention process provides a selectivity for acetic acid of at least 25, 30, 40, 50, 60, 70, 80, 85, 90, 91, 92, 93, 94, 95, 96, 97, 98, and 99%. Ethyl acetate is typically a co-product. Other products of the process can include one or more of ethanal, methanol, formic acid, and methyl acetate. Preferably, selectivity for all products other than acetic acid and ethyl acetate is less than 20, 15, 10, 9, 8, 7, 6, 5, 4, 3, 2 and 1%. In certain embodiments the yield of acetic acid ranges from 1.0 M to 15.0 M. PCT Application based on U.S. Provisional Application 63 / 537,919 In preferred embodiments the invention process provides a selectivity for ethyl acetate of at least 3, 5, 7, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, and 35%. Acetic acid is typically a co- product. Other products of the process can include one or more of ethanal, methanol, formic acid, and methyl acetate. Preferably, selectivity for all products other than ethyl acetate and acetic acid is less than 20, 15, 10, 9, 8, 7, 6, 5, 4, 3, 2 and 1%. In preferred embodiments the process provides space-time yields of 100-1,500 gL-1h-1including 200, 300, 350, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, and 1500 gL-1h-1. Space-time yield is product yield per unit reactor volume and per unit time. It quantifies productivity of a chemical process where a higher number is preferred. The invention process includes the production of acetic acid from bio-ethanol and air. For example, corn ethanol and air are converted into acetic acid. This provides a renewable, plant- based version of acetic acid for downstream chemical manufacturing. The reaction can be conducted under fed batch conditions, where oxygen is continuously supplied and a desired pressure (e.g., 75 psig) is maintained. Air (containing about 20% oxygen) can be used as well. The feedstock and reagents can be dosed in a glass tube, the air inside the glass tube is purged and replaced with oxygen, and then the system is pressurized to the desired pressure using oxygen or air, etc. The temperature of the system is raised to the desired temperature (e.g., 120oC), and an, e.g., 365nm LED light is optionally shined on the glass tube. After the reaction time (e.g., 1 hour), the light is turned off, and the reaction mixture is allowed to cool to room temperature. The product(s) can then be subjected to analysis, e.g., NMR and / or GC-MS analysis, and then separated and purified using common techniques in the art (distillation, etc.). EXAMPLES Numerous non-limiting Examples are summarized in Tables 1 and 2 below. General procedure for 1ml reaction in a batch reactor: To a 9 mL Ace Glass pressure tube containing a stir bar, 0.5 mL of 100 mM stock solution of N- hydroxyphthalimide (NHPI) in acetone, and 0.04 mL of 12.5 mM stock solution of Co(OAc)2 in methanol were introduced. The solvent was evaporated in a vacuum oven at room temperature. PCT Application based on U.S. Provisional Application 63 / 537,919 Then 0.25 mL of 4 mM stock solution of TBADT in d-ACN was added without drying.0.35 mL of d-ACN, and 0.4 mL 200 proof bio-ethanol were added to the Ace tube. The tube was tightly sealed on the manifold and was placed on a holder with 365 nm LED. The tube was purged with pure oxygen and was dosed with 75 psig pure oxygen, and the pressure was maintained during the reaction. The holder was heated up with a heat circulator at 120oC. When the temperature reached 120oC, LED light was turned on and the intensity of LED was 200 mW. After 1h, the LED light was turned off, oxygen tank was closed, and the reaction tube was allowed to cool to room temperature. Pressure was released before the tube was opened.0.1 mL of 0.5M solution of 1,4-dimethoxybenzene in d-DMSO was added as internal standard. For1H-NMR analysis, 50 µL of reaction solution with internal standard was added to 500 µL d-DMSO.

[0002] PCT Application based on U.S. Provisional Application 63 / 537,919 Table 1: Oxidation of ethanol in a fed-batch reactor. Unless otherwise specified, reaction conditions are: (i) Bioethanol used as feedstock; (ii) 1 ml of total reaction volume; (iii) solvent is deuterated acetonitrile (MeCN-d3) used to facilitate analysis by NMR. Non-deuterated MeCN results in similar performance; (iv) 75 psig of oxygen as co-feedstock, pressure is maintained under fed batch mode; (v) 120oC temperature; (vi) 1 hour reaction time; (vii) irradiation with 365nm LED. Ethanol Co- Acetic C2 volume Catalyst Co- catalyst Additive acid yield Acetic acid products(f)ty) 4% 0% 8% 8% 4% 4% 8% 7% 5% 4% 0% 8% 6% 0% Notes: (a) 200 proof bioethanol; (b) 190 proof bioethanol; (c) Reaction time = 2 hours; (d) Reaction time = 4 hours; (e) No light; (f) C2 products include acetic acid, ethanal and ethyl acetate. PCT Application based on U.S. Provisional Application 63 / 537,919 General procedure for 100 ml reaction in a bubble column reactor: To a 500 mL Ace Glass pressure tube containing a stir bar, 33 mg of Na2WO4∙2H2O, 408 mg of NHPI, and 8.9 mg of Co(OAc)2were added. The tube was sealed with a custom-made top equipped with a gas inlet, gas outlet, cooling coil, and thermometer. The gas inlet was connected to a gas diffuser positioned at the bottom of the tube. The pressure in the tube was controlled by a back pressure regulator (BPR) with 75 psig or 120 psig. The oxygen flow rate was controlled by a gas flow meter with 30 mL / min. The tube was heated to 130oC with a propylene glycol bath. When the temperature of the solution reached 80oC, the LED light was turned on. The tube was illuminated with one 40W 370nm Kessil lamp. After about 2h, the light was turned off, and the reaction tube was allowed to cool to room temperature. Pressure was released before the tube opened.14 g of 1,4-dimethoxybenzene was added as internal standard. For1H-NMR analysis, 15 µL of reaction solution with internal standard was added to 500 µL d-DMSO.

[0003] PCT Application based on U.S. Provisional Application 63 / 537,919 Table 2: Oxidation of ethanol in a bubble column reactor. Unless otherwise specified, reaction conditions are: (i) Bioethanol (190 proof) used as feedstock; (ii) 0.5mM of Co(OAc)2 used as additive; (iii) 100 ml of total reaction volume; (iv) 75-120 psig of oxygen as co-feedstock; (v) 120-130oC temperature; (vi) 2 hours reaction time; (vii) irradiation with 370nm LED. Ethanol Co- Co- Acetic Acetic Ethyl Ethyl C2 Entry volumeSolvent Catalyst Catalystacid acid acetate acetate products loadingcataly catalyst yield (selecti yield (selecti (selectivi Notes: (a) No light; (b) PTFE diffuser with 20 micron pore size used; (c) 2-CF3BP = 2- Trifluoromethyl-benzophenone; (d) C2 products include acetic acid, ethanal and ethyl acetate. While not limiting, preferred embodiments of the present invention, all of which are fully described and enabled herein, include the following: 1. A process, comprising reacting ethanol with oxygen in the presence of at least one carbon-hydrogen activation catalyst, optionally at least one co-catalyst, and optionally at least one additive to produce at least one of acetic acid and ethyl acetate, wherein said reacting is PCT Application based on U.S. Provisional Application 63 / 537,919 optionally conducted in the presence of at least one solvent and optionally conducted under light irradiation. 2. The process according to embodiment 1, wherein said reacting occurs under irradiation with light having a wavelength range of 250 – 450 nm, more preferably 300-400 nm, most preferably 340-370 nm such as 365 nm. 3. The process according to each individual preceding embodiment and any combination thereof, wherein said reacting occurs in the presence of said at least one co-catalyst. 4. The process according to each individual preceding embodiment and any combination thereof, wherein said reacting occurs in the presence of said at least one additive. 5. The process according to each individual preceding embodiment and any combination thereof, wherein said reacting occurs in the presence of said at least one solvent. 6. The process according to each individual preceding embodiment and any combination thereof, wherein said process produces acetic acid and provides a selectivity for acetic acid of at least 25, 30, 40, 50, 60, 70, 80, 85, 90, 91, 92, 93, 94, 95, 96, 97, 98, and 99%, and, optionally but preferably, a selectivity for all products other than acetic acid and ethyl acetate of less than 20, 15, 10, 9, 8, 7, 6, 5, 4, 3, 2 and 1%. 7. The process according to each individual preceding embodiment and any combination thereof, wherein said process produces ethyl acetate and provides a selectivity for ethyl acetate of at least 3, 5, 7, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, and 35%, and, optionally but preferably, a selectivity for all products other than ethyl acetate and acetic acid is less than 20, 15, 10, 9, 8, 7, 6, 5, 4, 3, 2 and 1%. 8. The process according to each individual preceding embodiment and any combination thereof, wherein said at least one catalyst is selected from at least one tungstate and / or cerium compound or complex, such as at least one of tetra-n-butylammonium decatungstate, sodium decatungstate, cerium (III) chloride, cerium (IV) sulfate, [NEt4]2[CeIVCl6], cerium ammonium nitrate, bis(acetylacetonato)dioxomolybdenum(VI), copper(II) chloride, benzophenone and its derivatives such as 2-trifluoromethylbenzophenone, xanthone and PCT Application based on U.S. Provisional Application 63 / 537,919 thioxanthone, and peroxides such as hydrogen peroxide, benzoyl peroxide, and di-tert-butyl peroxide where preferred catalysts include TBADT = Tetra-n-butylammonium decatungstate (e.g., CAS: 68109-03-5); NaDT = Sodium decatungstate (e.g., CAS: 126752-51-0); CeCl3= cerium(III) chloride (e.g., CAS: 7790-86-5); Na2WO42H2O = sodium tungstate dihydrate, MoO2(acac)2 = bis(acetylacetonato)dioxomolybdenum(VI), and 2-CF3BP = 2- trifluoromethylbenzophenone. 9. The process according to each individual preceding embodiment and any combination thereof, wherein said at least one co-catalyst is present and is at least one of N- hydroxyphthalimide, N-hydroxysuccinimide, N-Hydroxytetrachloropthalimide, 2,6- Dihydroxypyrrolo[3,4-f]isoindole-1,3,5,7(2H,6H)-tetraone, N-Hydroxymaleimide, 2-hydroxy- 1H-benzo[de]isoquinoline-1,3(2H)-dione, and 2-hydroxy-1H-benzo[f]isoindole-1,3(2H)-dione, where preferred co-catalysts include NHPI and derivatives of NHPI such as 1,3-dioxoisoindolin- 2-yl acetate and N-hydroxytetrachloropthalimide. 10. The process according to each individual preceding embodiment and any combination thereof, wherein said at least one additive is present and is selected from at least one of Fe(acac)3, cobalt (II) acetate and other cobalt, manganese, and zirconium complexes such as Co(acac)2, Co(acac)3,Mn(acac)3, and Cu(OAc)2, and zirconium acetate where Co(OAc)2 is a preferred additive. 11. The process according to each individual preceding embodiment and any combination thereof, wherein said optional solvent is present and is at least one of ethanol, methanol, propanol, isopropanol, acetonitrile, acetone, water, ethyl acetate, acetic acid, benzene, cyclohexane, chloroform, methylene chloride, hexane, toluene, xylene, carbon tetrachloride, ethyl acetate, dichloroethane, dimethyl carbonate, DMF, benzonitrile, anisole, methyl acetate, methyl benzoate, and benzonitrile, where acetic acid and ethyl acetate are preferred. 12. The process according to each individual preceding embodiment except embodiment 11 and any combination thereof, wherein said process is conducted in the absence of said optional solvent. PCT Application based on U.S. Provisional Application 63 / 537,919 13. The process according to each individual preceding embodiment and any combination thereof, wherein said oxygen may be added to / present in the reaction zone in mixture with one or more other gases, wherein pure oxygen and mixtures of oxygen with non- reactive gases such as nitrogen, carbon dioxide, any one or more of the noble gasses (helium, neon, argon, krypton, xenon and radon), etc., can be used, as well as other sources of oxygen, such as air, and wherein when a mixture of oxygen with at least one other nonreactive gas is used the mixture preferably contains at least 5% v / v oxygen, including 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and more where oxygen mixtures containing from less than 1% to 99+% oxygen can be used, preferably in mixture with one other gas, preferably nitrogen. 14. The process according to each individual preceding embodiment and any combination thereof, wherein the selectivity for all products other than acetic acid and ethyl acetate is less than 20, or 15, or 10, or 9, or 8, or 7, or 6, or 5, or 4, or 3, or 2 or 1%. 15. The process according to each individual preceding embodiment and any combination thereof, wherein the process achieves an ethanol conversion of at least 25, 30, 40, 50, 60, 70, 80, 85, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, and 99+%. 16. The process according to each individual preceding embodiment and any combination thereof, wherein the process is conducted at a temperature of 80oC – 180oC. 17. The process according to each individual preceding embodiment and any combination thereof, wherein said process is conducted at a pressure of 75-300 psig. 18. The process according to each individual preceding embodiment and any combination thereof, wherein said ethanol is 190 proof ethanol. 19. The process according to each individual preceding embodiment and any combination thereof, wherein said ethanol is 200 proof ethanol. 20. The process according to each individual preceding embodiment and any combination thereof, wherein said ethanol is bioethanol. PCT Application based on U.S. Provisional Application 63 / 537,919 The above written description of the invention provides a manner and process of making and using it such that any person of ordinary skill in the relevant art is enabled to make and use the same, this enablement being provided in particular for the subject matter of the preferred embodiments described below as well as the appended claims, which make up a part of the original description. This description is provided in the context of a particular application and its requirements. Various modifications to the embodiments will be readily apparent to those of ordinary skill in the relevant art, and the generic principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Thus, this invention is not intended to be limited to the embodiments shown but is to be accorded the widest scope consistent with the principles and features disclosed herein. In this regard, certain embodiments within the invention may not show every benefit of the invention, considered broadly. Each embodiment, preferred embodiment, aspect, etc., described herein can be used in combination with every and any other embodiment described herein, preferred or otherwise. Additionally, some of the aforedescribed features can be used to advantage without a corresponding use of other features in certain embodiments while, in other embodiments, an advantage can be obtained by using all features together.

Claims

PCT Application based on U.S. Provisional Application 63 / 537,919 CLAIMS What is claimed is:

1. A process, comprising reacting ethanol with oxygen in the presence of at least one catalyst, optionally at least one co-catalyst, and optionally at least one additive to produce at least one of acetic acid and ethyl acetate, wherein said reacting is optionally conducted in the presence of at least one solvent and optionally conducted under light irradiation.

2. The process according to claim 1, wherein said reacting occurs in the presence of said at least one co-catalyst.

3. The process according to claim 1, wherein said reacting occurs in the presence of said at least one additive.

4. The process according to claim 1, wherein said reacting occurs in the presence of said at least one solvent.

5. The process according to claim 1, wherein said reacting occurs under irradiation with light having a wavelength range of 250 – 450 nm.

6. The process of claim 1, wherein said process produces acetic acid and provides a selectivity of at least 50% for acetic acid.

7. The process of claim 1, wherein said process produces ethyl acetate and provides a selectivity of at least 20% for ethyl acetate.

8. The process of claim 1, wherein said at least one catalyst is selected from TBADT, NaDT, CeCl3, Na2WO42H2O, MoO2(acac)2, 2-trifluoromethylbenzophenone and di- tert-butyl peroxide.

9. The process of claim 1, wherein said at least one co-catalyst is present and is at least one of N-hydroxyphthalimide, N-hydroxysuccinimide, N-Hydroxytetrachloropthalimide, 2,6-Dihydroxypyrrolo[3,4-f]isoindole-1,3,5,7(2H,6H)-tetraone, N-Hydroxymaleimide, 2- hydroxy-1H-benzo[de]isoquinoline-1,3(2H)-dione, 2-hydroxy-1H-benzo[f]isoindole-1,3(2H)- dione, 1,3-dioxoisoindolin-2-yl acetate and N-hydroxytetrachloropthalimide.PCT Application based on U.S. Provisional Application 63 / 537,919 10. The process of claim 1, wherein said at least one additive is present and is selected from Co(OAc)2,Co(acac)2, Co(acac)3,Mn(acac)3, Cu(OAc)2, zirconium acetate, and Fe(acac)3.

11. The process of claim 1, wherein said optional solvent is present and is at least one of ethanol, methanol, propanol, isopropanol, acetonitrile, acetone, water, acetic acid, and ethyl acetate.

12. The process of claim 1, wherein said process is conducted in the absence of said optional solvent.

13. The process of claim 1, wherein said oxygen is supplied in the form of air.

14. The process of claim 1, wherein the selectivity for all products other than acetic acid and ethyl acetate is less than 20%.

15. The process of claim 1, wherein the process achieves an ethanol conversion of at least 25%.

16. The process of claim 1, wherein the process is conducted at a temperature of 80oC – 180oC.

17. The process of claim 1, wherein said process is conducted at a pressure of 75-300 psig.

18. The process of claim 1, wherein said ethanol is 190 proof ethanol.

19. The process of claim 1, wherein said ethanol is 200 proof ethanol.

20. The process of claim 1, wherein said ethanol is bioethanol.

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