Multiphase copper-based bimetallic catalyst, and preparation method and application thereof

Abstract

The present invention relates to the use of a supported bimetallic catalyst having the formula Cu-M / support in a process for producing ethylene glycol from an oxamide or oxamate compound by carrying out a reaction in which the oxamide or oxamate compound is hydrogenated by hydrogen (H2) to obtain ethylene glycol, where M represents Mn, Co, Ni or Fe, respectively, the catalyst comprises copper and metal M on a carrier, wherein the metal M is selected from manganese, cobalt, nickel and iron; the invention also relates to a catalyst.

Description

Technical Field

[0001] The present invention relates to a novel heterogeneous bimetallic catalyst, a method for preparing the same and its use, in particular for the hydrogenation of oxalamide or oxalic acid ester to synthesize ethylene glycol. Background Art

[0002] Ethylene glycol is an important raw material in the chemical industry and can be used in a variety of applications, such as antifreeze or refrigerants, in particular in the production of textile fibers and polyester resins. Ethylene glycol can be used as a monomer in the manufacture of polyesters, and in particular in the manufacture of PET (polyethylene terephthalate) in the presence of terephthalic acid. PET is a polymer widely used in the textile industry, which is currently produced mainly from petroleum-based products that generate large amounts of greenhouse gases (including carbon dioxide).

[0003] The classic method for making ethylene glycol is from naphtha and is illustrated below:

[0004]

[0005] Scheme 1: Classical method for producing ethylene glycol

[0006] The recovery of CO2 is a major challenge in reducing greenhouse gas emissions. Another synthetic route for ethylene glycol is the hydrogenation of oxalamide or oxalic acid ester, which has been less studied.

[0007] Oxamide compounds can be directly synthesized by dioxidative carbonylation of amines in the presence of a catalyst, particularly palladium (Pd).

[0008] Oxamate compounds can be directly synthesized by oxidative carbonylation of alcohols and amines in the presence of a catalyst, particularly palladium (Pd).

[0009] Thus, CO2 consumption can be achieved during the synthesis of oxamide or oxamate, which is a precursor for the production of ethylene glycol by hydrogenation catalyzed by transition metals (as homogeneous catalysts or heterogeneous catalysts), as shown schematically below:

[0010]

[0011] Scheme 2: Production of ethylene glycol from CO2 via intermediate oxamide or oxamate compounds Homogeneous transition metal-based catalysts are catalysts that are soluble in the reaction solvent and form a single phase.

[0012] Heterogeneous transition metal-based catalysts are insoluble catalysts that participate in reactions involving two phases (eg, liquid and solid).

[0013] Supported bimetallic catalysts consist of a support on the surface of which particles of two metals are dispersed and fixed in the form of the oxides of these metals, or in reduced form, or even as a mixture of these two forms.

[0014] The support is advantageously an oxide, for example alumina or silica.

[0015] It is understood that a bimetallic catalyst of two metals (Metal-1 and Metal-2) comprises two metal species (Metal-1 and Metal-2) on a support on a surface thereof accessible to a substrate for catalytic reaction.

[0016] Thus, a monometallic supported catalyst consists of a support on which particles of a single metal are dispersed and fixed in oxidic form, or in reduced form, or even in a mixture of both forms.

[0017] The metal-catalyzed hydrogenation of oxalamide or oxamate to ethylene glycol was carried out in the presence of a homogeneous catalysis of an organometallic complex of ruthenium or iron, as described in Dong et al. (Nature Communications, 7:12075, DOI: 10.1038 / ncomms12075, 2016).

[0018] US application US2012 / 0071693 by De Boer et al. discloses a method for preparing ethylene glycol by hydrogenating oxamide in the presence of a monometallic catalyst. The application includes the use of a monometallic catalyst selected from the list of transition metal elements of Group VIII of the Periodic Table and copper (an element in Group IB), with preferred metals being platinum, palladium, rhodium, ruthenium, nickel, and copper. However, tests performed with a copper catalyst have shown that partial conversion of oxamide of the formula NR2CO-CO-NR2 and partial hydrogenation of oxamide preferentially and selectively produce ethanolamine HOCH2CH2NR2 or amide of the formula HOCH2(CO)NR2.

[0019] Application US2015 / 0331923 by Chen et al. relates to a material consisting of a mixture of zirconium dioxide and manganese oxide as a catalyst support, in particular for the hydrogenation or hydrolysis of sugars.

[0020] Application US 2014 / 0249334 to Miller et al. relates to nickel-based supported catalysts on a zirconium dioxide support for the hydrogenolysis of polyols, in particular the support being doped with chromium.

[0021] For many years, there has been a need for a low-cost, environmentally friendly route to the production of ethylene glycol.

[0022] To date, a search has been underway for heterogeneous catalysts that are easy to prepare, allow for the efficient and environmentally friendly synthesis of ethylene glycol from oxamides or oxamate esters, are easily industrializable and safe.

[0023] Ethylene glycol is also a model compound for the cleavage of carbon-carbon (C-C) and / or carbon-oxygen (C-O) bonds of the diol groups -CHOH-CHOH- present in carbohydrate molecules (polyols) contained in biomass by the action of hydrogen (i.e., hydrogenolysis). Therefore, a catalyst capable of cleaving the C-C and C-O bonds of ethylene glycol by hydrogenolysis will be able to depolymerize biomass by cleaving the C-C and / or C-O bonds of the diol groups present in the biomass. Summary of the Invention

[0024] One of the objects of the present invention is to propose a process for preparing ethylene glycol from oxamide or oxamate by reaction using a heterogeneous bimetallic catalyst, in particular based on copper in combination with another metal.

[0025] Another object of the present invention is a process for preparing ethylene glycol with high efficiency and selectivity.

[0026] Another object of the present invention is to prepare ethylene glycol without using toxic reagents.

[0027] Another object of the present invention is to prepare ethylene glycol using recoverable or recycled reagents and efficient and reusable heterogeneous catalysts.

[0028] Another object of the present invention is to provide a process for hydrogenolysis of ethylene glycol using a heterogeneous bimetallic catalyst.

[0029] Another object of the present invention is to provide a process for depolymerization of biomass using a heterogeneous bimetallic catalyst.

[0030] Another object of the present invention is to provide novel supported heterogeneous bimetallic catalysts.

[0031] It is another object of the present invention to provide heterogeneous catalysts that can be used in continuous flow processes.

[0032] Another object of the present invention is to provide a simple, industrial and optimized process for preparing this catalyst. DETAILED DESCRIPTION

[0033] use

[0034] A first object of the present invention is the use of a supported bimetallic catalyst having the formula Cu-M / support, wherein M represents Mn, Co, Ni or Fe, respectively, in a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, the catalyst comprising copper and metal M on a support, the metal M being selected from manganese, cobalt, nickel and iron.

[0035] The present inventors have unexpectedly and surprisingly observed that a supported bimetallic catalyst based on copper and an M metal selected from the group consisting of Mn, Co, Ni and iron can catalyze the hydrogenation of oxamide or oxamate to produce ethylene glycol, in particular with a yield of ethylene glycol up to 80%.

[0036] The experiments (see Examples 14 and 15) show that for copper-based catalysts, the presence of a second metal selected from Mn, Co, Ni and Fe makes it possible to induce or promote the catalytic performance of the catalyst, thereby improving the production yield of ethylene glycol by increasing the conversion of the substrate and / or the selectivity for obtaining ethylene glycol, compared to the monometallic catalysts of the prior art.

[0037] For the purposes of the present invention, "oxamide" refers to an amine having the formula NR a R b Oxamide derivatives of 1,1'-oxalyldiamide:

[0038]

[0039] For the purposes of the present invention, "oxamate" refers to an oxalate derivative having the formula: a R b ) and an alkoxide group or an alcohol group:

[0040]

[0041] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-M / support as defined above in the implementation of a method for preparing ethylene glycol from an oxamide compound, wherein M represents Mn, Co, Ni or Fe, respectively, and the oxamide compound is hydrogenated by hydrogen (H2) to obtain ethylene glycol, the catalyst comprising copper and metal M on a support, the metal M being selected from manganese, cobalt, nickel and iron.

[0042] In the present invention, the terms "hydrogen" and "dihydro" define the same H2 molecule.

[0043] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-M / support as defined above in the implementation of a method for preparing ethylene glycol from an oxamate compound, wherein M represents Mn, Co, Ni or Fe, respectively, and the hydrogenation reaction of the oxamate compound is carried out by hydrogen (H2) to obtain ethylene glycol, and the catalyst comprises copper and metal M on a support, and the metal M is selected from manganese, cobalt, nickel and iron.

[0044] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-M / support as defined above in the implementation of a method for preparing ethylene glycol from a mixture of oxamide and oxamate, wherein M represents Mn, Co, Ni or Fe, respectively, and the hydrogenation reaction of the mixture of oxamide and oxamate is carried out by hydrogen (H2) to obtain ethylene glycol, the catalyst comprising copper and metal M on a support, the metal M being selected from manganese, cobalt, nickel and iron.

[0045] It is understood that the Cu-M / support catalyst is a heterogeneous catalyst, wherein the catalyst is in a solid phase and the reactants are in a liquid or gaseous state.

[0046] The advantage of using a heterogeneous catalyst is that it facilitates the separation of the catalyst from other species participating in the reaction, allows for easy recovery and reuse of the catalyst, and limits contamination of the product with transition metals.

[0047] The use of heterogeneous catalysts also has the advantage that, when operating under continuous flow, the catalyst can be immobilized in the reactor within an enclosure (eg a jacket) and a catalyst-free product can thus be obtained at the reactor outlet.

[0048] For the purposes of this invention, "catalyst" or "supported catalyst" refers to a material composed of a support on which the catalytic sites are located. It is understood that a bimetallic catalyst comprises the support as well as atoms of the metal M and the element copper. The total weight of the catalyst is equivalent to the weight of the support and the weight of the two metals, namely, copper and metal M.

[0049] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-M / support as defined above in the implementation of a method for preparing ethylene glycol from oxamide or oxamate compounds, wherein M represents Mn, Co, Ni or Fe, respectively, and the hydrogenation reaction of the oxamide or oxamate compound is carried out by hydrogen (H2) to obtain ethylene glycol, the catalyst comprising copper and metal M on a support, the metal M being selected from manganese, cobalt, nickel and iron, wherein the support is an oxide, in particular zirconium dioxide (ZrO2) or aluminum oxide (γ-Al2O3).

[0050] Advantageously, the support is an oxide, for example, zirconium dioxide ZrO2 and gamma alumina (γ-Al2O3).

[0051] For the purposes of the present invention, "oxide" refers to an oxide of a transition metal that is in solid form and is insoluble in a solvent.

[0052] Using Cu-Mn catalyst / support

[0053] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Mn / support as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, said catalyst comprising copper and manganese on a support.

[0054] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Mn / oxide as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, said catalyst comprising copper and manganese on an oxide support.

[0055] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Mn / ZrO2 as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, said catalyst comprising copper and manganese on a zirconium dioxide support.

[0056] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Mn / γ-Al2O3 as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, said catalyst comprising copper and manganese on a γ-alumina support.

[0057] Using Cu-Co catalyst / support

[0058] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Co / support as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, the catalyst comprising copper and cobalt on a support.

[0059] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Co / oxide as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, said catalyst comprising copper and cobalt on an oxide support.

[0060] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Co / ZrO2 as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, the catalyst comprising copper and cobalt on a zirconium dioxide support.

[0061] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Co / γ-Al2O3 as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, the catalyst comprising copper and cobalt on a γ-alumina support.

[0062] Using catalyst Cu-Ni / support

[0063] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Ni / support as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, the catalyst comprising copper and nickel on a support.

[0064] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Ni / oxide as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, said catalyst comprising copper and nickel on an oxide support.

[0065] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Ni / ZrO2 as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, the catalyst comprising copper and nickel on a zirconium dioxide support.

[0066] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Ni / γ-Al2O3 as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, the catalyst comprising copper and nickel on a γ-alumina support.

[0067] Using Cu-Fe catalyst / support

[0068] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Fe / support as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, said catalyst comprising copper and iron on a support.

[0069] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Fe / oxide as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, said catalyst comprising copper and iron on an oxide support.

[0070] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Fe / ZrO2 as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, said catalyst comprising copper and iron on a zirconium dioxide support.

[0071] According to a specific embodiment, the present invention relates to the use of a supported bimetallic catalyst having the formula Cu-Fe / γ-Al2O3 as defined above in the implementation of a process for preparing ethylene glycol from oxamide or oxamate compounds, wherein the oxamide or oxamate compounds are hydrogenated by hydrogen (H2) to obtain ethylene glycol, said catalyst comprising copper and iron on a γ-alumina support.

[0072] Oxamide

[0073] According to a specific embodiment, the present invention relates to the use as defined above, wherein the oxamide has the following formula 1:

[0074]

[0075] Among them, R a and R b Independently of each other:

[0076] Hydrogen atoms,

[0077] C1 to C 20 a straight-chain or branched alkyl group,

[0078] C2 to C 20 a straight-chain or branched alkenyl group,

[0079] C1 to C 20 a straight-chain or branched heteroalkyl group,

[0080] C3 to C 20 an aryl or heteroaryl group,

[0081] C5 to C 20 an alkyl-aryl or alkyl-heteroaryl group,

[0082] C3 to C 10 cycloalkyl groups,

[0083] R a or R b At least one of the groups is different from hydrogen,

[0084] R a and R b Can be covalently linked and form a ring.

[0085] According to a particular embodiment, the present invention relates to the use as defined above, wherein the oxamide is selected from oxamides prepared with diethylamine, piperidine, pyrrolidine, morpholine and aniline, preferably piperidine.

[0086] Oxamate

[0087] According to a specific embodiment, the present invention relates to the use as defined above, wherein the oxamate has the following formula 2:

[0088]

[0089] Among them, R a and R b Independently means:

[0090] Hydrogen atoms,

[0091] C1 to C 20 a straight-chain or branched alkyl group,

[0092] C2 to C 20 a straight-chain or branched alkenyl group,

[0093] C1 to C 20 a straight-chain or branched heteroalkyl group,

[0094] C3 to C 20 an aryl or heteroaryl group,

[0095] C5 to C 20 an alkyl-aryl or alkyl-heteroaryl group,

[0096] C3 to C 10 cycloalkyl groups,

[0097] R a or R b At least one of the groups is different from hydrogen,

[0098] R a and R b Can be covalently linked to form a ring,

[0099] Among them, R c represents a group selected from the following:

[0100] C1 to C 10 a straight-chain or branched alkyl group, and

[0101] C3 to C 10 cycloalkyl groups,

[0102] C3 to C 20 an aryl or heteroaryl group,

[0103] C5 to C 20 Alkyl-aryl or alkyl-heteroaryl groups.

[0104] According to a specific embodiment, the present invention relates to the use as defined above, wherein the oxamate is selected from oxamate prepared with diethylamine, piperidine, pyrrolidine, morpholine and aniline (preferably piperidine) and water, methanol, ethanol or isopropanol.

[0105] From CO2

[0106] Advantageously, the oxamide used is obtainable by carbonylation of amines in the presence of CO and oxygen.

[0107] Advantageously, the oxamate used is obtainable by carbonylation of an amine with an alcohol or water in the presence of CO and oxygen.

[0108] Advantageously, the carbon monoxide CO used for preparing oxamide or oxamate originates from the electrolysis of carbon dioxide CO2 to carbon monoxide CO.

[0109] Therefore, the synthesis of ethylene glycol is advantageously carried out from the recovery of CO2.

[0110] Use of catalyst preparation via soft chemistry

[0111] According to a particular embodiment, the invention relates to the use as defined above, wherein the catalyst is prepared by mixing the support in powder form with an aqueous solution of a copper salt and a salt of a metal M chosen from Mn, Co, Ni and Fe, followed by drying and calcination.

[0112] According to a particular embodiment, the invention relates to the use as defined above, in which the catalyst is prepared by mixing the support in powder form with an aqueous solution of a copper salt and a salt of a metal M (without additives or surfactants, in particular without ammonia solution), followed by drying the material obtained and calcining the material.

[0113] It will be appreciated that the mixture of the support in powder form with the aqueous solution of the copper salt and the salt of the metal M consists of contacting the solution of the copper salt and the salt of the metal M with the support and that the support is thus impregnated with the copper salt and the salt of the metal M, i.e. copper atoms and metal M atoms are deposited on the surface of the support, said M being selected from the group consisting of Mn, Co, Ni and Fe.

[0114] “Drying” means an operation consisting of heating the material and ambient air in a closed enclosure to a temperature of about 60°C to 100°C for a period of 10 hours to 24 hours to dry the material, i.e., to remove water molecules (i.e., free water, water adsorbed on the surface or in the interstitial space).

[0115] "Calcination" refers to an operation consisting of heating a solid material in ambient air in a closed enclosure to an elevated temperature of about 400°C to 1000°C to activate it or change the physical properties of the support and to remove bound water and salts of metal precursors (e.g., nitrates and acetates). After calcination, the material is free of water.

[0116] Advantageously, the catalyst used is prepared by the following preparation method, which comprises the following steps:

[0117] ●Step A: Dissolve in an aqueous solution (5 mL to 10 mL by volume of water)

[0118] The copper salt and the salt of metal M are impregnated on a support in powder form, and the ratio of the mass of the solution to the mass of the support is 0.6 to 1.0, wherein M is selected from Mn, Co, Ni and Fe;

[0119] To obtain the catalyst Cu-M / support in the form of a homogeneous mixture,

[0120] Step B, drying the homogeneous mixture to obtain the catalyst Cu-M / support in the form of a dry homogeneous mixture,

[0121] • An activation step C, comprising calcining said dried homogeneous mixture to obtain said catalyst.

[0122] For the purposes of the present invention, a "homogeneous mixture" means a homogeneous material obtained by mixing an aqueous solution of a metal salt, which is uniformly distributed on the surface of the particles constituting the support and in the interstices of said particles, with a support in solid powder form.

[0123] A "dried homogeneous mixture" is a homogeneous mixture from which most of the free water molecules adsorbed on the surface of the particles of the support or in the interstices have been removed, for example, by drying at 60° C. to 100° C. (particularly at 80° C.) to obtain a powder. The preparation of the catalyst results in the formation of the corresponding insoluble metal oxides, since the metal salts (e.g., nitrates) of the metals are completely removed after the calcination step at 600° C.

[0124] Advantageously, during the impregnation of step A, the aqueous solution containing the copper salt and the salt of the metal M, said M being selected from Mn, Co, Ni and Fe, is free of additives and surfactants. In other words, the aqueous impregnation solution consists of a demineralized aqueous solution in which the copper salt and the salt of the metal M are dissolved.

[0125] Advantageously, the salt of metal M is a nitrate and the copper salt is copper nitrate.

[0126] Therefore, the use according to the present invention is carried out by preparing the catalyst using an aqueous solution, which is a non-hazardous green solvent compared to the organic solvents used in the prior art. Advantageously, no additional additives and surfactants are required in the synthesis of the catalyst, making it more industrializable at a lower cost.

[0127] "Green solvents" are non-toxic, biodegradable or agro-based alternative solvents that have the same properties as the toxic solvents they replace.

[0128] Use of catalysts with properties related to specific surface area

[0129] According to a particular embodiment, the present invention relates to the use as defined above, wherein the catalyst has a surface area of ​​1 m 2 / g to 250m 2 / g.

[0130] 1m 2 / g to 250m 2 The range of / g includes the following ranges: 1m 2 / g to 25m 2 / g; 25m 2 / g to 50m 2 / g; 50m 2 / g to 75m 2 / g;75m 2 / g to 100m2 / g; 100m 2 / g to 125m 2 / g; 125m 2 / g to 150m 2 / g; 150m 2 / g to 175m 2 / g; 175m 2 / g to 200m 2 / g; 200m 2 / g to 225m 2 / g; 225m 2 / g to 250m 2 / g.

[0131] According to a particular embodiment, the present invention relates to the use as defined above, wherein the catalyst has a surface area of ​​1 m 2 / g to 50m 2 / g.

[0132] 1m 2 / g to 50m 2 The range of / g includes the following ranges: 1m 2 / g to 10m 2 / g; 10m 2 / g to 20m 2 / g; 20m 2 / g to 30m 2 / g; 30m 2 / g to 40m 2 / g; 40m 2 / g to 50m 2 / g.

[0133] According to a particular embodiment, the present invention relates to the use as defined above, wherein the catalyst has a surface area of ​​1 m 2 / g to 10m 2 / g, preferably about 5m 2 / g.

[0134] 1m 2 / g to 10m 2 The range of / g includes the following ranges: 1m 2 / g to 2m 2 / g; 2m 2 / g to 3m 2 / g; 3m 2 / g to 4m 2 / g; 4m 2 / g to 5m 2 / g; 5m 2 / g to 6m2 / g; 6m 2 / g to 7m 2 / g;7m 2 / g to 8m 2 / g;8m 2 / g to 9m 2 / g、9m 2 / g to 10m 2 / g, especially about 5m 2 / g.

[0135] Using a catalyst with a specific crystal structure on a ZrO2 support

[0136] According to a particular embodiment, the invention relates to the use of a catalyst Cu-M / ZrO2 as defined above, wherein said catalyst comprises a crystalline phase crystallizing in the monoclinic system as analyzed by X-ray diffraction.

[0137] "Monoclinic" refers to a crystal system having one of the following symmetry point groups: 2, m, or 2 / m.

[0138] According to a particular embodiment, the invention relates to the use of a Cu-M / ZrO2 catalyst as defined above, wherein said crystalline phase represents from 50% to 90% of the total weight of the catalyst.

[0139] According to a particular embodiment, the invention relates to the use of a catalyst Cu-M / ZrO2 as defined above, wherein the crystalline phase is baddeleyite.

[0140] According to a particular embodiment, the invention relates to the use of a catalyst Cu-M / ZrO 2 as defined above, wherein the catalyst support is natural zirconium dioxide (ZrO 2 ) crystallized as monoclinic zirconite.

[0141] For the purposes of the present invention, "badgeonis" refers to natural zirconium oxide having the formula ZrO2, containing 0.1% to 5% hafnium oxide, and crystallizing in the monoclinic system. The characteristics of baddeleyite (e.g., its composition and crystal structure, particularly its space group and lattice dimensions) are reported and provided in the prior art and are known to those skilled in the art, for example, by Kudoh, Y. et al. (Phys Chem Minerals 13, 233-237 (1986)) or McCullough, J. D. et al. (Acta Crystallographica 12 (1959) 507-511).

[0142] According to a particular embodiment, the invention relates to the use as defined above, wherein the zirconium dioxide ZrO 2 catalyst support comprises impurities, such as hafnium (Hf), rhenium (Re) and silicon (Si) atoms.

[0143] Advantageously, the mass ratio between hafnium atoms and zirconium atoms (Hf / Zr) is less than 5%.

[0144] Advantageously, the mass ratio between rhenium atoms and zirconium atoms (Re / Zr) is less than 5%.

[0145] Advantageously, the mass ratio between silicon atoms and zirconium atoms (Si / Zr) is less than 2%.

[0146] According to a particular embodiment, the invention relates to the use as defined above, wherein the catalyst has a microstructure whose crystallite size is between 15 nm and 100 nm, preferably between 15 nm and 50 nm.

[0147] The crystal structure of the catalyst can be analyzed by powder X-ray diffraction. By comparing the diffraction peaks in the obtained diffraction pattern with reference materials, the phases present and their structures can be analyzed.

[0148] For example, the baddeleyite crystalline phase of zirconium dioxide ZrO 2 is shown in ICDD reference no. 00-037-1484.

[0149] From the diffraction pattern, the grain size can be estimated according to the following Scherrer formula:

[0150]

[0151] The range of "15 nm to 100 nm" includes the following ranges: 15 nm to 20 nm; 20 nm to 30 nm; 30 nm to 40 nm; 40 nm to 50 nm; 50 nm to 60 nm; 60 nm to 70 nm; 70 nm to 80 nm; 80 nm to 90 nm; 90 nm to 100 nm.

[0152] Using catalysts with specific Cu and metal M contents

[0153] According to a particular embodiment, the invention relates to the use as defined above, wherein the total content of the bimetallic elements copper and metal M, selected from Mn, Co, Ni and Fe, is between 0.5% and 25% by weight of the total catalyst.

[0154] The total weight of the catalyst includes the mass of the support and the mass of the copper and metal M bimetallic elements.

[0155] The range of 0.5% to 25% includes the following ranges: 0.5% to 5%; 5% to 10%; 10% to 15%; 15% to 20%; 20% to 25%.

[0156] According to a particular embodiment, the invention relates to the use as defined above, wherein the total content of the bimetallic elements copper and the metal M is between 5% and 20% by weight of the total catalyst.

[0157] The “total content of bimetallic copper and metal M” refers to the content of elemental copper and metal M added to the catalyst.

[0158] According to a particular embodiment, the invention relates to the use as defined above, wherein the total content of elemental copper is from 1% to 25% by weight of the total catalyst, in particular from 1% to 10% by weight of the total catalyst.

[0159] According to a specific embodiment, the invention relates to the use as defined above, wherein the total content of elemental metals M is from 1% to 25% by weight of the total catalyst, in particular from 1% to 10% by weight of the total catalyst, and M is chosen from Mn, Co, Ni and Fe.

[0160] According to a particular embodiment, the present invention relates to the use as defined above, wherein:

[0161] - a total content of elemental copper of 1 to 25% by weight, based on the total weight of the catalyst, in particular of 1 to 10% by weight, based on the total weight of the catalyst,

[0162] - and a total content of elemental metals M of 1 to 25% by weight, based on the total weight of the catalyst,

[0163] In particular, it is from 1 to 10% by weight, based on the total weight of the catalyst.

[0164] According to a particular embodiment, the invention relates to the use as defined above, in which the mass of copper is greater than the mass of metal M.

[0165] According to a particular embodiment, the invention relates to the use as defined above, wherein the mass of metal M is greater than the mass of copper.

[0166] According to a particular embodiment, the invention relates to the use as defined above, wherein the weight ratio of metal M to copper varies from 1:1 to 1:10, preferably from 1:1 to 1:5, in particular the weight ratio is 1:2.

[0167] According to a particular embodiment, the invention relates to the use as defined above, wherein the mass composition of the metal M and copper of the catalyst is M(5%)Cu(10%), said M being selected from Mn, Co, Ni and Fe.

[0168] The mass composition M(5%)Cu(10%) corresponds to a metal M content of 5% based on the total weight of the catalyst and a Cu content of 10% based on the total weight of the catalyst, ie, a mass ratio of metal M to copper of 1:2.

[0169] Using CuMn / support catalysts with surface characteristics of Cu and Co

[0170] According to a particular embodiment, the invention relates to the use as defined above, wherein the catalyst is a Cu-Mn / support and wherein the catalyst has a molar amount of more than 50% of elemental copper in oxidation degree (II) and / or wherein elemental manganese in oxidation degrees (II), (III) and (IV) is present.

[0171] According to a particular embodiment, the invention relates to the use as defined above, wherein the catalyst is CuMn / ZrO2 and the catalyst has a molar amount of elemental copper in oxidation degree (II) and / or elemental manganese in oxidation degree (II) greater than 50%.

[0172] According to a particular embodiment, the invention relates to the use as defined above, wherein the catalyst is CuMn / γ-Al2O3 and the catalyst has a molar amount of elemental copper in oxidation degree (II) and / or elemental manganese in oxidation degree (III) greater than 50%.

[0173] Using CuCo / ZrO2 catalyst with surface characteristics of Cu and Co

[0174] According to a particular embodiment, the invention relates to the use as defined above, wherein the catalyst is CuCo / ZrO2 and has a molar amount greater than 50% of elemental copper in oxidation degree (II) and / or elemental cobalt in oxidation degree (II).

[0175] The present inventors have unexpectedly found that for the hydrogenation of oxamide or oxamate to ethylene glycol, a CoCu / ZrO2 bimetallic catalyst can be used directly after preparation by calcination in air, without any prior reduction step of the copper and cobalt atoms under hydrogen before using the catalyst in the hydrogenation reaction.

[0176] Advantageously, the use of a catalyst in which the majority of the copper and cobalt elements are already present in oxidized form allows the catalyst to be used before carrying out the hydrogenation reaction of oxamide or oxamate to ethylene glycol, without requiring prior reduction of the copper and cobalt elements in the catalyst. This also makes it possible to avoid storing the catalyst in an inert atmosphere to prevent oxidation of the copper and cobalt atoms.

[0177] According to a particular embodiment, the invention relates to the use as defined above, wherein the catalyst CuCo / ZrO2 has a molar amount of greater than 50% of elemental copper in oxidation degree (II) and greater than 50% of elemental cobalt in oxidation degree (II).

[0178] According to a particular embodiment, the invention relates to the use as defined above, wherein the catalyst CuCo / ZrO2 has a molar amount of greater than 70% of elemental copper in oxidation degree (II) and greater than 65% of elemental cobalt in oxidation degree (II).

[0179] According to a specific embodiment, the invention relates to the use as defined above, wherein the catalyst CuCo / ZrO2 has a molar amount of greater than 50% of elemental copper in oxidation degree (II) in the form of CuO and greater than 50% of elemental cobalt in oxidation degree (II) in the form of Co2O3 or Co(OH)2.

[0180] According to a specific embodiment, the present invention relates to the use as defined above, wherein the catalyst CuCo / ZrO2 has a molar amount of more than 70% of elemental copper in oxidation degree (II) in the form of CuO and a molar amount of more than 65% of elemental cobalt in oxidation degree (II) in the form of Co2O3 or Co(OH)2.

[0181] According to a particular embodiment, the present invention relates to the use as defined above, wherein the catalyst CuCo / ZrO2 has:

[0182] - from 10 to 30% by mole of elemental copper in the metallic state in oxidation degree (0) or in the form of Cu2O in oxidation degree (I),

[0183] - and from 10 to 35% by mole of elemental cobalt in the metallic state in the oxidation state (0).

[0184] According to a particular embodiment, the present invention relates to the use as defined above, wherein the catalyst CuCo / ZrO2 has:

[0185] - a molar amount of more than 70% of elemental copper in the form of CuO in oxidation degree (II),

[0186] - from 10 to 30% by mole of elemental copper in the metallic state in oxidation degree (0) or in the form of Cu2O in oxidation degree (I),

[0187] - from 10 to 35% by mole of elemental cobalt in the metallic state at the oxidation degree (0),

[0188] - and more than 65% by molar amount of elemental cobalt in the form of Co2O3 or Co(OH)2 in oxidation degree (II).

[0189] Using a catalyst with a specific morphology, CuCo / ZrO2

[0190] According to a particular embodiment, the invention relates to the use as defined above, wherein the catalyst CuCo / ZrO2 is in the form of a population of micronized particles ranging from 1 μm to 500 μm.

[0191] The range of 1 μm to 500 μm includes the following ranges: 1 μm to 50 μm; 50 μm to 100 μm; 100 μm to 200 μm; 200 μm to 300 μm; 300 μm to 400 μm.

[0192] "Particles" refer to distinct clusters that have either visual or mechanical consistency.

[0193] According to a particular embodiment, the invention relates to the use as defined above, wherein the catalyst CuCo / ZrO2 is in the form of a group of particles having a rounded morphology.

[0194] For the purposes of the present invention, "round particles" refer to particles that have no edges, angles, or bevels.

[0195] catalyst

[0196] The second subject of the present invention relates to a supported bimetallic catalyst having the formula Cu-M / support, wherein M represents Mn, Co, Ni or Fe, said catalyst comprising copper and a metal M on a support, said metal M being selected from manganese, cobalt, nickel and iron.

[0197] Catalyst Cu-M / γ-Al2O3

[0198] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-M / γ-Al2O3, said catalyst comprising copper and a metal M selected from the group consisting of Mn, Co, Ni and Fe on a γ-alumina support,

[0199] The catalyst has a specific surface area of ​​1 m 2 / g to 250m 2 / g, preferably 100m 2 / g to 200m 2 / g, more preferably 150m 2 / g to 160m 2 / g,

[0200] And optionally, wherein the catalyst comprises a crystalline phase comprising a crystallite size less than 10 nm as analyzed by X-ray diffraction.

[0201] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-M / γ-Al2O3, said catalyst comprising copper and metal M on the surface of a γ-alumina support, said M being selected from Mn and Co,

[0202] The catalyst has a specific surface area of ​​100 m 2 / g to 200m 2 / g.

[0203] Catalyst Cu-M / ZrO2

[0204] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-M / ZrO2, said catalyst comprising copper and a metal M selected from the group consisting of Mn, Co, Ni and Fe on a zirconium dioxide support,

[0205] The catalyst has a specific surface area of ​​1 m 2 / g to 250m 2 / g, preferably 1m 2 / g to 50m 2 / g, preferably 1m 2 / g to 10m 2 / g, especially about 5m 2 / g,

[0206] And wherein, the catalyst includes a crystalline phase, which is monoclinic crystallized by X-ray diffraction analysis, especially the crystalline phase accounts for 50% to 90% of the total weight of the catalyst, preferably, the crystalline phase is baddeleyite and preferably includes a grain size of 15nm to 100nm.

[0207] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-M / ZrO2, said catalyst comprising copper and a metal M selected from the group consisting of Mn, Co, Ni and Fe on the surface of a zirconium dioxide support.

[0208] Specific surface area

[0209] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / ZrO2 as defined above, wherein said catalyst has a specific surface area of ​​1 m 2 / g to 50m 2 / g.

[0210] According to a specific embodiment, the present invention relates to a bimetallic catalyst having the formula Cu-M / ZrO2, said catalyst comprising copper and a metal M selected from Mn and Co on the surface of a zirconium dioxide support,

[0211] The catalyst has a specific surface area of ​​1 m 2 / g to 50m 2 / g.

[0212] According to a particular embodiment, the present invention relates to a bimetallic catalyst as defined above, wherein the zirconium dioxide support is manganese-free and / or chromium-free.

[0213] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / ZrO2 as defined above, wherein said catalyst has a specific surface area of ​​1 m 2 / g to 10m 2 / g, preferably about 5m 2 / g.

[0214] According to a specific embodiment, the present invention relates to a bimetallic catalyst having the formula Cu-M / ZrO2 as defined above, said catalyst comprising copper and a metal M selected from Mn and Co on the surface of a zirconium dioxide support,

[0215] The catalyst has a specific surface area of ​​1 m 2 / g to 10m 2 / g, preferably about 5m 2 / g.

[0216] structure

[0217] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / ZrO2 as defined above, wherein said crystalline phase represents 50% to 90% of the total weight of the catalyst.

[0218] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / ZrO2 as defined above, wherein the crystalline phase is baddeleyite.

[0219] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / ZrO2 as defined above, wherein the catalyst support of zirconium dioxide ZrO2 comprises impurities such as hafnium (Hf) atoms, rhenium (Re) atoms and silicon (Si) atoms.

[0220] Advantageously, the mass ratio between hafnium atoms and zirconium atoms (Hf / Zr) is less than 5%.

[0221] Advantageously, the mass ratio between rhenium atoms and zirconium atoms (Re / Zr) is less than 5%.

[0222] Advantageously, the mass ratio between silicon atoms and zirconium atoms (Si / Zr) is less than 2%.

[0223] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst Cu—M / ZrO 2 as defined above, wherein said catalyst has a microstructure with a grain size ranging from 15 nm to 100 nm, preferably from 15 nm to 50 nm.

[0224] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / ZrO2 as defined above, wherein:

[0225] - The catalyst has a specific surface area of ​​1 m 2 / g to 250m 2 / g, especially 1m 2 / g to 50m 2 / g, preferably 1m 2 / g to 10m 2 / g,

[0226] - The catalyst comprises a crystalline phase, which is crystallized in a monoclinic system according to X-ray diffraction analysis.

[0227] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / ZrO2 as defined above, wherein:

[0228] - The catalyst has a specific surface area of ​​1 m 2 / g to 10m 2 / g,

[0229] - The catalyst comprises a crystalline phase, which is crystallized as monoclinic zircon by X-ray diffraction analysis, and has a crystallite size of 15 nm to 100 nm, preferably 15 nm to 50 nm.

[0230] - and including impurities such as hafnium (Hf) atoms, rhenium (Re) atoms and silicon (Si)

[0231] atom.

[0232] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / ZrO2 having the formula Cu-M / ZrO2 as defined above, said catalyst comprising copper and a metal M selected from the group consisting of Mn, Co, Ni and Fe on a zirconium dioxide support,

[0233] The catalyst has a specific surface area of ​​1 m 2 / g to 250m 2 / g, preferably 1m 2 / g to 50m 2 / g, more preferably 1m 2 / g to 10m 2 / g, especially about 5m2 / g,

[0234] And wherein, the catalyst includes a crystalline phase, which is monoclinic crystallized by X-ray diffraction analysis, especially the crystalline phase accounts for 50% to 90% of the total weight of the catalyst, preferably, the crystalline phase is baddeleyite and preferably includes a grain size of 15nm to 100nm.

[0235] According to a specific embodiment, the present invention relates to a bimetallic catalyst having the formula Cu-M / ZrO2 as defined above, said catalyst comprising copper and a metal M selected from Mn and Co on the surface of a zirconium dioxide support,

[0236] The zirconium dioxide carrier includes a crystalline phase, and X-ray diffraction analysis shows that the phase is monoclinic.

[0237] According to a specific embodiment, the present invention relates to a bimetallic catalyst having the formula Cu-M / ZrO2 as defined above, said catalyst comprising copper and a metal M selected from Mn and Co on the surface of a zirconium dioxide support,

[0238] The crystalline phase accounts for 50% to 90% of the total weight of the catalyst.

[0239] The range of 50% to 90% includes the following ranges: 50% to 55%, 55% to 60%, 60% to 65%, 65% to 70%, 70% to 75%, 75% to 80%, 80% to 85%, and 85% to 90%.

[0240] According to a particular embodiment, the present invention relates to a bimetallic catalyst having the formula Cu-M / ZrO2 as defined above, comprising copper and a metal M selected from Mn and Co on the surface of a zirconium dioxide support, wherein the crystalline phase is baddeleyite.

[0241] Advantageously, the catalyst according to the invention comprises from 50% to 90% baddeleyite.

[0242] Advantageously, the zirconium dioxide catalyst support according to the invention consists of more than 50% baddeleyite, in particular of 50% to 100% baddeleyite.

[0243] According to a specific embodiment, the present invention relates to a bimetallic catalyst having the formula Cu-M / ZrO2 as defined above, comprising copper and a metal M on the surface of a zirconium dioxide support, said M being selected from Mn and Co, wherein said catalyst comprises a crystalline phase comprising a grain size of 15 nm to 100 nm as analyzed by X-ray diffraction.

[0244] composition

[0245] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / support as defined above, wherein the catalyst comprises the bimetallic element copper and the metal M in an amount of 0.5% to 25% by weight based on the total weight of the catalyst, wherein the M is selected from the group consisting of Mn, Co, Ni and Fe.

[0246] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / support as defined above, wherein the catalyst comprises the bimetallic element copper and the metal M in an amount of 5% to 20% by weight based on the total weight of the catalyst, wherein the M is selected from the group consisting of Mn, Co, Ni and Fe.

[0247] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / support as defined above, wherein the total content of elemental copper is from 1% to 25% by weight, preferably from 1% to 10% by weight, based on the total weight of the catalyst.

[0248] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / support as defined above, wherein the total content of elemental metal M is from 1% to 25% by weight of the total catalyst, preferably from 1% to 10% by weight of the total catalyst, and M is selected from Mn, Co, Ni and Fe.

[0249] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / support as defined above, wherein the weight ratio of metal M to copper varies from 1:1 to 1:10, preferably the weight ratio is 1:2.

[0250] Cu-Mn / support (ZrO2 or γ-Al2O3): degree of oxidation of Mn and Cu on the surface

[0251] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst Cu-Mn / support as defined above, wherein the catalyst has a molar amount of elemental copper in oxidation degree (II) of greater than 50%, and / or wherein elemental manganese is present in oxidation degrees (II), (III) and (IV).

[0252] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst Cu-Mn / ZrO2 as defined above, wherein the catalyst has a molar amount of elemental copper in oxidation degree (II) and / or elemental manganese in oxidation degree (II) greater than 50%.

[0253] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst Cu-Mn / γ-Al2O3 as defined above, wherein the catalyst has a molar amount of elemental copper in oxidation degree (II) and / or elemental manganese in oxidation degree (III) greater than 50%.

[0254] CuCo / ZrO2: Oxidation degree of Co and Cu on the surface

[0255] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst CuCo / ZrO2 as defined above, wherein the catalyst has a molar amount of elemental copper in oxidation degree (II) and / or elemental cobalt in oxidation degree (II) greater than 50%.

[0256] Advantageously, in some cases, the following bimetallic catalyst, CuCo / ZrO2, can be used before carrying out the hydrogenation reaction of oxamide or oxamate to ethylene glycol without prior reduction of the copper and cobalt elements of the catalyst: the majority of the elemental copper and cobalt are already present in oxidized form. This also makes it possible to avoid storing the catalyst in an inert atmosphere to avoid oxidation of the copper and cobalt atoms.

[0257] According to a particular embodiment, the invention relates to the catalyst CuCo / ZrO2 as defined above, wherein said catalyst has a molar amount of greater than 50% of elemental copper in oxidation degree (II) and greater than 50% of elemental cobalt in oxidation degree (II).

[0258] According to a particular embodiment, the invention relates to the catalyst CuCo / ZrO2 as defined above, wherein said catalyst has a molar amount of greater than 70% of elemental copper in oxidation degree (II) and greater than 65% of elemental cobalt in oxidation degree (II).

[0259] According to a specific embodiment, the present invention relates to the catalyst CuCo / ZrO2 as defined above, wherein the catalyst has a molar amount of greater than 50% of elemental copper in oxidation degree (II) in the form of CuO and greater than 50% of elemental cobalt in oxidation degree (II) in the form of Co2O3 or Co(OH)2.

[0260] According to a specific embodiment, the present invention relates to the catalyst CuCo / ZrO2 as defined above, wherein the catalyst has a molar amount of more than 70% of elemental copper in oxidation degree (II) in the form of CuO and a molar amount of more than 65% of elemental cobalt in oxidation degree (II) in the form of Co2O3 or Co(OH)2.

[0261] According to a particular embodiment, the present invention relates to a catalyst CuCo / ZrO2 as defined above, wherein said catalyst has:

[0262] - from 10 to 30% by mole of elemental copper in the metallic state at the oxidation degree (0),

[0263] Or in the form of Cu2O in oxidation degree (I).

[0264] According to a particular embodiment, the present invention relates to a catalyst CuCo / ZrO2 as defined above, wherein said catalyst has:

[0265] - from 10 to 30% by mole of elemental copper in the metallic state in oxidation degree (0) or in the form of Cu2O in oxidation degree (I),

[0266] - and from 10 to 35% by mole of elemental cobalt in the metallic state in the oxidation state (0).

[0267] According to a particular embodiment, the present invention relates to a catalyst CuCo / ZrO2 as defined above, wherein said catalyst has:

[0268] - a molar amount of more than 70% of elemental copper in the form of CuO in oxidation degree (II),

[0269] - from 10 to 30% by mole of elemental copper in the metallic state in oxidation degree (0) or in the form of Cu2O in oxidation degree (I),

[0270] - and more than 65% by molar amount of elemental cobalt in the form of Co2O3 or Co(OH)2 in oxidation degree (II).

[0271] According to a particular embodiment, the present invention relates to a catalyst CuCo / ZrO2 as defined above, wherein said catalyst has:

[0272] - a molar amount of more than 70% of elemental copper in the form of CuO in oxidation degree (II),

[0273] - from 10 to 30% by mole of elemental copper in the metallic state in oxidation degree (0) or in the form of Cu2O in oxidation degree (I),

[0274] - from 10 to 35% by mole of elemental cobalt in the metallic state at the oxidation degree (0),

[0275] - and more than 65% by molar amount of elemental cobalt in the form of Co2O3 or Co(OH)2 in oxidation degree (II).

[0276] According to a particular embodiment, the present invention relates to a catalyst CuCo / ZrO2 as defined above, wherein said catalyst has:

[0277] - a molar amount of more than 50% of elemental copper in oxidation state (II) and more than 50% of elemental cobalt in oxidation state (II),

[0278] -Specific surface area is 1m 2 / g to 50m 2 / g,

[0279] - The crystalline phase was analyzed by X-ray diffraction and was found to be monoclinic.

[0280] According to a particular embodiment, the present invention relates to a catalyst CuCo / ZrO2 as defined above, wherein said catalyst has:

[0281] - a molar amount of more than 70% of elemental copper in the form of CuO in oxidation degree (II),

[0282] - from 10 to 30% by mole of elemental copper in the metallic state in oxidation degree (0) or in the form of Cu2O in oxidation degree (I),

[0283] - more than 65% by molar amount of elemental cobalt in the form of Co2O3 or Co(OH)2 in oxidation degree (II),

[0284] -Specific surface area is 1m by BET analysis 2 / g to 50m 2 / g, especially 1m 2 / g to 10m 2 / g,

[0285] - and a crystalline phase, analyzed by X-ray diffraction, crystallizing in the monoclinic system, in particular baddeleyite, including in particular impurities of hafnium, rhenium and silicon.

[0286] According to a particular embodiment, the present invention relates to a catalyst CuCo / ZrO2 as defined above, wherein said catalyst has:

[0287] - a molar amount of more than 70% of elemental copper in the form of CuO in oxidation degree (II),

[0288] - from 10 to 30% by mole of elemental copper in the metallic state in oxidation degree (0) or in the form of Cu2O in oxidation degree (I),

[0289] - from 10 to 35% by mole of elemental cobalt in the metallic state at the oxidation degree (0),

[0290] - more than 65% by molar amount of elemental cobalt in the form of Co2O3 or Co(OH)2 in oxidation degree (II),

[0291] -Specific surface area is 1m by BET analysis 2 / g to 50m 2 / g, especially 1m 2 / g to 10m 2 / g,

[0292] - and crystalline phases, analyzed by X-ray diffraction, crystallizing in the monoclinic system, in particular baddeleyite, in particular hafnium, rhenium and silicon impurities.

[0293] Morphology of catalyst Cu-M / ZrO2

[0294] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst Cu-M / ZrO2 as defined above, wherein said catalyst is in the form of micronized particles ranging from 1 μm to 500 μm, preferably in the form of a cluster of particles with a rounded morphology.

[0295] Morphology of Cu-Mn / ZrO2 catalyst

[0296] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst Cu—Mn / ZrO 2 as defined above, wherein said catalyst is in the form of micronized particles ranging from 1 μm to 500 μm, preferably in the form of a cluster of particles with a rounded morphology.

[0297] Morphology of CuCo / ZrO2 catalyst

[0298] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst CuCo / ZrO2 as defined above, wherein said catalyst is in the form of micronized particles ranging from 1 μm to 500 μm.

[0299] As a non-limiting example, morphology and average size can be assessed by scanning electron microscopy (SEM).

[0300] The micron size makes the catalyst easier to handle.

[0301] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst CuCo / ZrO2 as defined above, wherein the catalyst comprises the bimetallic elements copper and cobalt in a total content of 0.5% to 25% by weight of the total weight of the catalyst, preferably the weight ratio between cobalt and copper varies from 1:1 to 1:10, preferably from 1:1 to 1:5,

[0302] and / or wherein the catalyst has a molar amount of elemental copper in oxidation degree (II) and / or elemental cobalt in oxidation degree (II) greater than 50%,

[0303] And / or wherein the catalyst is in the form of a population of micronized particles ranging from 1 μm to 500 μm, preferably in the form of a population of particles having a rounded morphology.

[0304] These particles consist in particular of agglomerates of rods in a ratio of 1 to 10 and have an average thickness of 50 nm to 500 nm.

[0305] Morphology of Cu-Mn / γ-Al2O3 catalyst

[0306] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst Cu—Mn / γ-Al 2 O 3 as defined above, wherein said catalyst is in the form of micronized particles ranging from 1 μm to 500 μm, preferably in the form of a cluster of particles with a rounded morphology.

[0307] Characteristics of catalysts under reducing atmosphere

[0308] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst as defined above, wherein said catalyst is analyzed by performing a temperature-programmed reduction (TPR) in a dihydrogen reducing atmosphere at a temperature ranging from 30°C to 900°C, characterized in that the reduction temperature of metallic copper with a degree of oxidation (0) ranges from 150°C to 250°C.

[0309] Advantageously, at a temperature above said reduction temperature of metallic copper, in particular at least 10° C. above, more than 80%, in particular 80% to 100%, preferably 100%, of the copper atoms are in metallic form.

[0310] The range of 80% to 100% includes the following ranges: 80% to 85%, 85% to 90%, 90% to 95%, 95% to 96%, 96% to 97%, 97% to 98%, 98% to 99%, and 99% to 100%.

[0311] Advantageously, at a temperature above the reduction temperature of metallic copper, in particular at least 10° C. above, more than 80%, in particular 80% to 100%, preferably 100%, of the metal M atoms are in oxidized form, ie at a degree of oxidation greater than zero.

[0312] Advantageously, at a temperature above the reduction temperature of the metallic copper, in particular at least 10° C. above, 0% to 20%, in particular 0% to 10%, preferably less than 5% of the metal M atoms are in the metallic state with zero oxidation degree.

[0313] The range of 0% to 20% includes the following values: 0.0%, 0.05%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%.

[0314] Advantageously, at a temperature above said reduction temperature of metallic copper, in particular at least 10° C. above, the metal M is Co and 80% to 100% of the cobalt atoms are in oxidized form, or at least 10%, preferably at least 20% of the cobalt atoms are in metallic form.

[0315] Advantageously, at a temperature above said reduction temperature of metallic copper, in particular at least 10° C. above, the metal M is Mn and 95% to 100%, preferably 100%, of the manganese atoms are in oxidized form, ie at a degree of oxidation greater than zero.

[0316] Advantageously, at a temperature above said reduction temperature of metallic copper, in particular at least 10° C. above, the metal M is Fe and 95% to 100%, preferably 100%, of the iron atoms are in oxidized form, ie at a degree of oxidation greater than zero.

[0317] Advantageously, at a temperature above said reduction temperature of metallic copper, in particular at least 10° C. above, the metal M is Ni and 95% to 100%, preferably 100%, of the nickel atoms are in oxidized form.

[0318] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst as defined above, wherein said catalyst is analyzed by performing a temperature-programmed reduction (TPR) in a dihydrogen reducing atmosphere at a temperature ranging from 30°C to 900°C, characterized in that the reduction temperature of metallic copper with a degree of oxidation (0) ranges from 150°C to 250°C,

[0319] In particular, at a temperature at least 10° C. higher than the reduction temperature of said metallic copper as analyzed by TPR,

[0320] 80% to 100%, preferably 100%, of the copper atoms are in metallic form,

[0321] From 80% to 100%, preferably 100%, of the atoms of the metal M are in oxidized form.

[0322] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst as defined above, wherein the catalyst is analyzed by performing temperature-programmed reduction (TPR) in a reducing atmosphere of a 5 vol% H2 flow in argon (especially at 30 mL / min) in a temperature range of 30°C to 900°C, especially at a heating rate of 5°C / min, characterized in that the reduction temperature of metallic copper with degree of oxidation (0) is in the range of 150°C to 250°C.

[0323] Advantageously, before said analysis, the catalyst is pretreated in an inert atmosphere, in particular under helium, at 200°C.

[0324] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst as defined above, wherein, under a reducing atmosphere of hydrogen, at a pressure of 2 MPa to 10 MPa and a temperature of 150° C. to 250° C., in particular 180° C. to 220° C., the catalyst comprises 80% to 100%, in particular 95% to 100%, preferably 100%, of metallic copper atoms Cu(0), and 80% to 100% of metal M atoms in a degree of oxidation greater than zero, preferably, the metal M is not in metallic form.

[0325] Advantageously, 95%, preferably 100%, of the copper atoms are in metallic form.

[0326] Advantageously, 80% to 100%, in particular 95% to 100%, preferably 100%, of the atoms of the metal M are in oxidized form with a degree of oxidation greater than zero.

[0327] Advantageously, 0% to 20%, in particular 0% to 15%, preferably less than 20%, of the cobalt atoms are in metallic form.

[0328] Advantageously, 95%, preferably 100%, of the manganese atoms are in oxidized form with a degree of oxidation greater than zero.

[0329] Advantageously, 95%, preferably 100%, of the iron atoms are in oxidized form with a degree of oxidation greater than zero.

[0330] Advantageously, 95%, preferably 100%, of the nickel atoms are in oxidized form.

[0331] Preparation method of ethylene glycol

[0332] A third object of the present invention relates to a method for preparing ethylene glycol, comprising:

[0333] o a hydrogenation step of an oxamide or oxamate compound to ethylene glycol by hydrogen in the presence of a supported bimetallic catalyst having the formula Cu-M / support (wherein M represents Mn, Co, Ni or Fe), said catalyst comprising copper and metal M on a support,

[0334] The metal M is selected from manganese, cobalt, nickel and iron.

[0335] According to a particular embodiment, the invention relates to a preparation process as defined above, wherein the support is chosen from oxides, in particular zirconium dioxide (ZrO2) and gamma-aluminum oxide (γ-Al2O3).

[0336] According to a particular embodiment, the present invention relates to a preparation method as defined above, wherein the catalyst support is zirconium dioxide (ZrO2).

[0337] According to a specific embodiment, the present invention relates to a preparation method as defined above, wherein the catalyst support is zirconium dioxide (ZrO2) and gamma-aluminum oxide (γ-Al2O3).

[0338] According to a specific embodiment, the present invention relates to the preparation method as defined above, wherein the oxamide compound has the following formula 1:

[0339]

[0340] Among them, R a and R b Independently of each other:

[0341] Hydrogen atoms,

[0342] C1 to C 20 a straight-chain or branched alkyl group,

[0343] C2 to C 20 a straight-chain or branched alkenyl group,

[0344] C1 to C 20 a straight-chain or branched heteroalkyl group,

[0345] C3 to C 20 an aryl or heteroaryl group,

[0346] C5 to C 20 an alkyl-aryl or alkyl-heteroaryl group,

[0347] C3 to C 10 cycloalkyl groups,

[0348] R a or R b At least one of the groups is different from hydrogen,

[0349] R a and R b Can form a ring.

[0350] According to a specific embodiment, the present invention relates to a process for preparing ethylene glycol as defined above, wherein the oxamide compound is selected from oxamides prepared with diethylamine, piperidine, pyrrolidine, morpholine and aniline (preferably piperidine).

[0351] According to a specific embodiment, the present invention relates to the preparation method as defined above, wherein the oxamate compound has the following formula 2:

[0352]

[0353] Among them, R a and R b Independently of each other:

[0354] Hydrogen atoms,

[0355] C1 to C 20 a straight-chain or branched alkyl group,

[0356] C2 to C 20 a straight-chain or branched alkenyl group,

[0357] C1 to C 20 a straight-chain or branched heteroalkyl group,

[0358] C3 to C 20 an aryl or heteroaryl group,

[0359] C5 to C 20 an alkyl-aryl or alkyl-heteroaryl group,

[0360] C3 to C 10 cycloalkyl groups,

[0361] R a or R b At least one of the groups is different from hydrogen,

[0362] R a and R b Can be covalently linked to form a ring,

[0363] Among them, R c represents a group selected from the following:

[0364] C1 to C 10 a straight-chain or branched alkyl group, and

[0365] C3 to C 10 cycloalkyl groups,

[0366] C3 to C 20 an aryl or heteroaryl group,

[0367] C5 to C 20 Alkyl-aryl or alkyl-heteroaryl groups.

[0368] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0369] The hydrogenation step includes:

[0370] o Contacting the following to obtain a reaction medium that can be pressurized:

[0371] - the oxamide or oxamate compound,

[0372] -dihydrogen,

[0373] - the supported bimetallic catalyst having the formula Cu-M / support, wherein

[0374] M represents Mn, Co, Ni or Fe, the catalyst comprises copper and metal M on a support, the metal M being selected from manganese, cobalt, nickel and iron,

[0375] - Optional base

[0376] - optionally a solvent,

[0377] o optionally, heating the reaction medium,

[0378] to obtain ethylene glycol.

[0379] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0380] The hydrogenation step includes

[0381] o contacting the following to obtain a reaction medium,

[0382] - the oxamide or oxamate compound,

[0383] -dihydrogen,

[0384] - the supported bimetallic catalyst having the formula Cu-M / support, wherein

[0385] M represents Mn, Co, Ni or Fe, the catalyst comprises copper and metal M on a support, the metal M being selected from manganese, cobalt, nickel and iron,

[0386] - alkali,

[0387] - solvent,

[0388] o optionally, heating the reaction medium,

[0389] to obtain ethylene glycol.

[0390] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0391] ●The hydrogenation steps include

[0392] o Contacting the following to obtain a reaction medium:

[0393] - the oxamide or oxamate compound,

[0394] -dihydrogen,

[0395] - the supported bimetallic catalyst having the formula Cu-M / support, wherein

[0396] M represents Mn, Co, Ni or Fe, the catalyst comprises copper and metal M on a support, the metal M being selected from manganese, cobalt, nickel and iron,

[0397] - alkali,

[0398] - solvent,

[0399] o heating the reaction medium,

[0400] to obtain ethylene glycol.

[0401] Cu-Mn / support (ZrO2 or γ-Al2O3)

[0402] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0403] The hydrogenation step includes

[0404] o Contacting the following to obtain a reaction medium that can be pressurized:

[0405] - the oxamide or oxamate compound,

[0406] -dihydrogen,

[0407] - said supported bimetallic catalyst having the formula Cu-Mn / support, said catalyst comprising copper and manganese on a support,

[0408] - optionally a base,

[0409] - optionally a solvent,

[0410] o optionally, heating the reaction medium,

[0411] to obtain ethylene glycol.

[0412] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0413] The hydrogenation step includes

[0414] o Contacting the following to obtain a reaction medium that can be pressurized:

[0415] - the oxamide or oxamate compound,

[0416] -dihydrogen,

[0417] - said supported bimetallic catalyst having the formula Cu-Mn / oxide, said catalyst comprising copper and manganese on an oxide support,

[0418] - Optional base

[0419] - optionally a solvent,

[0420] o optionally, heating the reaction medium,

[0421] to obtain ethylene glycol.

[0422] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0423] The hydrogenation step includes

[0424] o Contacting the following to obtain a reaction medium that can be pressurized:

[0425] - the oxamide or oxamate compound,

[0426] -dihydrogen,

[0427] - said supported bimetallic catalyst having the formula Cu-Mn / ZrO2, said catalyst comprising copper and manganese on a zirconium dioxide support,

[0428] - Optional base

[0429] - optionally a solvent,

[0430] o optionally, heating the reaction medium,

[0431] to obtain ethylene glycol.

[0432] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0433] The hydrogenation step includes

[0434] o Contacting the following to obtain a reaction medium that can be pressurized:

[0435] - the oxamide or oxamate compound,

[0436] -dihydrogen,

[0437] - said supported bimetallic catalyst having the formula Cu-Mn / γ-Al2O3, said catalyst comprising copper and manganese on a γ-alumina support,

[0438] - Optional base

[0439] - optionally a solvent,

[0440] o optionally, heating the reaction medium,

[0441] to obtain ethylene glycol.

[0442] Cu-Co / support (ZrO2 or γ-Al2O3)

[0443] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0444] The hydrogenation step includes

[0445] o Contacting the following to obtain a reaction medium that can be pressurized:

[0446] - the oxamide or oxamate compound,

[0447] -dihydrogen,

[0448] - said supported bimetallic catalyst having the formula Cu-Co / support, said catalyst comprising copper and cobalt on a support,

[0449] - Optional base

[0450] - optionally a solvent,

[0451] o optionally, heating the reaction medium,

[0452] to obtain ethylene glycol.

[0453] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0454] The hydrogenation step includes

[0455] o Contacting the following to obtain a reaction medium that can be pressurized:

[0456] - the oxamide or oxamate compound,

[0457] -dihydrogen,

[0458] - said supported bimetallic catalyst having the formula Cu-Co / oxide, said catalyst comprising copper and cobalt on an oxide support,

[0459] - optionally a base,

[0460] - optionally a solvent,

[0461] o optionally, heating the reaction medium,

[0462] to obtain ethylene glycol.

[0463] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0464] The hydrogenation step includes

[0465] o Contacting the following to obtain a reaction medium that can be pressurized:

[0466] - the oxamide or oxamate compound,

[0467] -dihydrogen,

[0468] - said supported bimetallic catalyst having the formula Cu-Co / ZrO2, said catalyst comprising copper and cobalt on a zirconium dioxide support,

[0469] - optionally a base,

[0470] - optionally a solvent,

[0471] o optionally, heating the reaction medium,

[0472] to obtain ethylene glycol.

[0473] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0474] The hydrogenation step includes:

[0475] o Contacting the following to obtain a reaction medium that can be pressurized:

[0476] - the oxamide or oxamate compound,

[0477] -dihydrogen,

[0478] - said supported bimetallic catalyst having the formula Cu-Co / γ-Al2O3, said catalyst comprising copper and cobalt on a γ-alumina support,

[0479] - optionally a base,

[0480] - optionally a solvent,

[0481] o optionally, heating the reaction medium,

[0482] to obtain ethylene glycol.

[0483] Cu-Ni / support (ZrO2 or γ-Al2O3)

[0484] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0485] The hydrogenation step includes

[0486] o Contacting the following to obtain a reaction medium that can be pressurized:

[0487] - the oxamide or oxamate compound,

[0488] -dihydrogen,

[0489] - said supported bimetallic catalyst having the formula Cu-Ni / support, said catalyst comprising copper and nickel on a support,

[0490] - Optional base

[0491] - optionally a solvent,

[0492] o optionally, heating the reaction medium,

[0493] to obtain ethylene glycol.

[0494] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0495] The hydrogenation step includes

[0496] o Contacting the following to obtain a reaction medium that can be pressurized:

[0497] - the oxamide or oxamate compound,

[0498] -dihydrogen,

[0499] - said supported bimetallic catalyst having the formula Cu-Ni / oxide, said catalyst comprising copper and nickel on an oxide support,

[0500] - optionally a base,

[0501] - optionally a solvent,

[0502] o optionally, heating the reaction medium,

[0503] to obtain ethylene glycol.

[0504] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0505] The hydrogenation step includes

[0506] o Contacting the following to obtain a reaction medium that can be pressurized:

[0507] - the oxamide or oxamate compound,

[0508] -dihydrogen,

[0509] - said supported bimetallic catalyst having the formula Cu-Ni / ZrO2, said catalyst comprising copper and nickel on a zirconium dioxide support,

[0510] - optionally a base,

[0511] - optionally a solvent,

[0512] o optionally, heating the reaction medium,

[0513] to obtain ethylene glycol.

[0514] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0515] The hydrogenation step includes

[0516] o Contacting the following to obtain a reaction medium that can be pressurized:

[0517] - the oxamide or oxamate compound,

[0518] -dihydrogen,

[0519] - said supported bimetallic catalyst having the formula Cu-Ni / γ-Al2O3, said catalyst comprising copper and nickel on a γ-alumina support,

[0520] - optionally a base,

[0521] - optionally a solvent,

[0522] o optionally, heating the reaction medium,

[0523] to obtain ethylene glycol.

[0524] Cu-Fe / support (ZrO2 or γ-Al2O3)

[0525] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0526] The hydrogenation step includes

[0527] o Contacting the following to obtain a reaction medium that can be pressurized:

[0528] - the oxamide or oxamate compound,

[0529] -dihydrogen,

[0530] - said supported bimetallic catalyst having the formula Cu-Fe / support, said catalyst comprising copper and iron on a support,

[0531] - optionally a base,

[0532] - optionally a solvent,

[0533] o optionally, heating the reaction medium,

[0534] to obtain ethylene glycol.

[0535] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0536] The hydrogenation step includes

[0537] o Contacting the following to obtain a reaction medium that can be pressurized:

[0538] - the oxamide or oxamate compound,

[0539] -dihydrogen,

[0540] - said supported bimetallic catalyst having the formula Cu-Fe / oxide, said catalyst comprising copper and iron on an oxide support,

[0541] - optionally a base,

[0542] - optionally a solvent,

[0543] o optionally, heating the reaction medium,

[0544] to obtain ethylene glycol.

[0545] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0546] ●The hydrogenation steps include

[0547] o Contacting the following to obtain a reaction medium that can be pressurized:

[0548] - the oxamide or oxamate compound,

[0549] -dihydrogen,

[0550] - said supported bimetallic catalyst having the formula Cu-Fe / ZrO2, said catalyst comprising copper and iron on a zirconium dioxide support,

[0551] - optionally a base,

[0552] - optionally a solvent,

[0553] o optionally, heating the reaction medium,

[0554] to obtain ethylene glycol.

[0555] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein:

[0556] The hydrogenation step includes

[0557] o Contacting the following to obtain a reaction medium that can be pressurized:

[0558] - the oxamide or oxamate compound,

[0559] -dihydrogen,

[0560] - said supported bimetallic catalyst having the formula Cu-Fe / γ-Al2O3, said catalyst comprising copper and iron on γ-alumina,

[0561] - optionally a base,

[0562] - optionally a solvent,

[0563] o optionally, heating the reaction medium,

[0564] to obtain ethylene glycol.

[0565] Method for preparing ethylene glycol using a catalyst

[0566] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein the catalyst is a catalyst according to the present invention as defined above.

[0567] According to a particular embodiment, the invention relates to a process for the preparation of ethylene glycol as defined above, wherein the catalyst is prepared by mixing the support in powder form with an aqueous solution of copper and cobalt salts, followed by calcination.

[0568] According to a particular embodiment, the invention relates to a process for the preparation of ethylene glycol as defined above, wherein the catalyst is prepared by mixing the support in powder form with an aqueous solution of copper and cobalt salts, without adding additives or surfactants, followed by calcination.

[0569] Advantageously, the catalyst Cu-M / support used in the process as defined above is prepared according to a preparation method comprising the following steps:

[0570] Step A: Dissolve in an aqueous solution (5 mL to 10 mL by volume of water)

[0571] The copper salt and the salt of the metal M are impregnated on a support in powder form, in particular on zirconium dioxide or γ-alumina, wherein the ratio of the mass of the solution to the mass of the support is 0.6 to 1.0;

[0572] to obtain the catalyst Cu-M / support in the form of a homogeneous mixture,

[0573] Step B, drying the homogeneous mixture to obtain the catalyst Cu-M / support in the form of a dry homogeneous mixture,

[0574] • An activation step C, comprising calcining said dried homogeneous mixture to obtain said catalyst.

[0575] Advantageously, during the impregnation step A, the aqueous solution containing the copper salt and the salt of a metal M, said M being chosen from Mn, Co, Ni and Fe, is free of additives and surfactants. In other words, the aqueous impregnation solution consists of a demineralized aqueous solution in which the salt of the metal M and the copper salt are dissolved.

[0576] Advantageously, the salt of metal M is a nitrate and the copper salt is copper nitrate.

[0577] Thus, the process for preparing ethylene glycol according to the invention as defined above is carried out with a catalyst prepared from an aqueous solution, advantageously free of additives and surfactants, making it more industrializable and less costly.

[0578] Catalyst Cu-M / ZrO2

[0579] According to a specific embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein the catalyst Cu-M / ZrO2 has a specific surface area of ​​1 m 2 / g to 250m 2 / g, especially 1m 2 / g to 50m 2 / g, preferably 1m 2 / g to 10m 2 / g, more preferably about 5m 2 / g.

[0580] According to a specific embodiment, the present invention relates to a process for preparing ethylene glycol as defined above, wherein the catalyst Cu-M / ZrO2 comprises a crystalline phase, which, by X-ray diffraction analysis, crystallizes in the monoclinic system, in particular baddeleyite,

[0581] Optionally, the crystalline phase of the Cu-M / ZrO2 catalyst accounts for 50% to 90% of the total weight of the catalyst,

[0582] Optionally, the crystallite size of the crystalline phase is 15 nm to 40 nm.

[0583] Conditions for the preparation of ethylene glycol

[0584] According to a particular embodiment, the invention relates to a process for the preparation of ethylene glycol as defined above, wherein the catalyst is used in a proportion of 0.1 mmol to 10 mmol of copper, in particular in a proportion of 4 mmol of Cu.

[0585] The range of 0.1 mmol to 10 mmol includes the following ranges: 0.1 mmol to 0.5 mmol, 0.5 mmol to 1 mmol, 1 mmol to 2 mmol, 2 mmol to 3 mmol, 3 mmol to 4 mmol.

[0586] According to a specific embodiment, the present invention relates to a process for preparing ethylene glycol as defined above, wherein the oxamide or oxamate compound is used in a ratio of 2 to 400 molar equivalents, in particular 5 equivalents, relative to metallic Cu.

[0587] The range of 2 molar equivalents (eq.) to 400 molar equivalents (eq.) includes the following ranges: 2eq. to 3eq., 3eq. to 4eq., 4eq. to 5eq., 5eq. to 10eq., 10eq. to 50eq., 50eq. to 100eq., 100eq. to 200eq., 200eq. to 300eq., 300eq. to 400eq.

[0588] According to a particular embodiment, the invention relates to a process for the preparation of ethylene glycol as defined above, wherein the hydrogen used is at a pressure ranging from 2 MPa to 10 MPa, in particular at 6 MPa.

[0589] The expression MPa corresponds to 10 6 Pascal, which is equivalent to 10 bar.

[0590] The expression "2.0 MPa to 10.0 MPa" corresponds to the following ranges: 2.0 MPa to 2.5 MPa; 2.5 MPa to 3.0 MPa; 3.0 MPa to 3.5 MPa; 3.5 MPa to 4.0 MPa; 4.0 MPa to 4.5 MPa; 4.5 MPa to 5.0 MPa; 5.0 MPa to 5.5 MPa; 5.5 MPa to 6.0 MPa; 6.0 MPa to 6.5 MPa; 6.5 MPa to 7.0 MPa; 7.0 MPa to 7.5 MPa; 7.5 MPa to 8.0 MPa; 8.0 MPa to 8.5 MPa; 8.5 MPa to 9.0 MPa; 9.0 MPa to 9.5 MPa; 9.5 MPa to 10 MPa.

[0591] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein the solvent is selected from dioxane, xylene, mesitylene, tetrahydrofuran (THF), 2-methyltetrahydrofuran, toluene, in particular THF.

[0592] According to a particular embodiment, the invention relates to a process for the preparation of ethylene glycol as defined above, wherein the reaction medium is placed at a pressure ranging from 2 MPa to 10 MPa, in particular at 6 MPa.

[0593] According to a particular embodiment, the invention relates to a process for the preparation of ethylene glycol as defined above, wherein the reaction medium is heated to a temperature ranging from 100°C to 250°C, in particular from 180°C to 200°C.

[0594] The range of 100°C to 250°C includes the following ranges: 100°C to 110°C, 110°C to 120°C, 120°C to 130°C, 130°C to 140°C, 140°C to 150°C, 150°C to 160°C, 160°C to 170°C, 170°C to 180°C, 180°C to 190°C, 190°C to 200°C, 200°C to 210°C, 210°C to 220°C, 220°C to 230°C, 230°C to 240°C, and 240°C to 250°C.

[0595] According to a particular embodiment, the invention relates to a process for the preparation of ethylene glycol as defined above, wherein the reaction medium is heated for 5 to 24 hours, in particular for 8 to 16 hours.

[0596] Catalyst in activated form

[0597] According to a specific embodiment, the present invention relates to a process for preparing ethylene glycol as defined above,

[0598] Among them, hydrogen is used at a pressure of 2 MPa to 10 MPa, particularly 6 MPa.

[0599] wherein the reaction medium is heated to a temperature of 100° C. to 250° C., in particular 180° C. to 220° C., optionally wherein the reaction medium is heated for 5 hours to 24 hours, in particular 8 hours or 16 hours,

[0600] wherein, during the step of heating the reaction medium, the supported bimetallic catalyst is activated, the activated catalyst comprising:

[0601] 80% to 100%, in particular 95% to 100%, preferably 100%, of metallic copper atoms Cu(0) in a zero oxidation state, and

[0602] - 80% to 100% of the metal M atoms in a degree of oxidation greater than zero, preferably,

[0603] The metal M is not in metallic form.

[0604] Advantageously, 95%, preferably 100%, of the copper atoms are in metallic form.

[0605] Advantageously, 80% to 100%, in particular 95% to 100%, preferably 100%, of the atoms of the metal M are in oxidized form with a degree of oxidation greater than zero.

[0606] Advantageously, 0% to 20%, in particular 0% to 15%, preferably less than 20%, of the cobalt atoms are in metallic form.

[0607] Advantageously, 95%, preferably 100%, of the manganese atoms are in oxidized form with a degree of oxidation greater than zero.

[0608] Advantageously, 95%, preferably 100%, of the iron atoms are in oxidized form with a degree of oxidation greater than zero.

[0609] Advantageously, 95%, preferably 100%, of the nickel atoms are in oxidized form.

[0610] Advantageously, embodiments of the process according to the present invention do not require pre-activation of the catalyst by reducing metal species, but rather activate the catalyst in situ during the process.

[0611] The catalytic substance (i.e., metallic copper with a degree of oxidation (0)) for the hydrogenation reaction of oxamide or oxamate is formed in situ. The second metal element M is mainly in an oxidized form on the support surface and acts as a promoter for the copper used to catalyze the hydrogenation reaction of oxamide or oxamate. Therefore, the bimetallic catalyst based on copper and metal M can be directly introduced into the oxamide or oxamate hydrogenation method according to the present invention, and does not need to be reduced to a metallic form in advance to start the hydrogenation reaction. Unlike many bimetallic catalysts in the prior art, it is inactive under the first reduction step without a catalytic substance.

[0612] Conditions for the flow method

[0613] The method according to the invention can be implemented in a flow chemistry instrument, for example, in a commercial reactor, for example, the "H-Cube" by Thales Nano INC. "or" ” (7 Zahony Street, Graphisoft Park, Building D, H-1031 Budapest, Hungary), or for example the “E-series” or “R-series flow chemistry system” reactors of Vapourtec Ltd (Unit 21 / Park Farm Business Centre / Fornham Pk, Bury Saint Edmunds IP28 6TS, UK).

[0614] Advantageously, the continuous flow process is carried out at a temperature of 100°C to 250°C.

[0615] Advantageously, the continuous flow process is carried out at a pressure of 0.1 MPa to 10 MPa.

[0616] According to a specific embodiment, the continuous flow process is carried out in a reactor wherein the gas occupies 10% to 90% of the reactor volume.

[0617] The expression "10% to 90%" corresponds to the following ranges: 10% to 20%; 20% to 30%; 30% to 40%; 40% to 50%; 50% to 60%; 60% to 70%; 70% to 80%; 80% to 90%.

[0618] According to a specific embodiment, the continuous flow method is carried out by making the contact time between the reactants 1 second to 2 hours, in particular 1 second to 2 minutes.

[0619] The expression "1 second to 2 hours" corresponds to the following scales: 1 second to 15 seconds; 15 seconds to 30 seconds; 30 seconds to 1 minute; 1 minute to 2 minutes; 2 minutes to 15 minutes; 15 to 30 minutes; 30 minutes to 1 hour; 1 hour to 2 hours.

[0620] According to a specific embodiment, the hydrogenation step of the method is carried out in a continuous flow and comprises a device for introducing a hydrogen gas stream into the reactor to contact the substrate (oxalamide or oxamate).

[0621] According to a particular embodiment, the present invention relates to a process for the preparation of ethylene glycol as defined above, wherein the substrate (i.e. oxamide or oxamate or a mixture thereof) is circulated under flow and / or hydrogen is circulated under flow, passing through or in contact with the catalyst.

[0622] Catalyst preparation method

[0623] The fourth object of the present invention relates to a method for preparing a Cu-M / support catalyst, comprising:

[0624] Step A, impregnating a copper salt and a salt of a metal M dissolved in an aqueous solution (5 mL to 10 mL by volume of water) without additives and surfactants on a support in powder form, wherein M is selected from Mn, Co, Ni and Fe, and the ratio of the mass of the solution to the mass of the support is 0.6 to 1.0;

[0625] to obtain the catalyst Cu-M / support in the form of a homogeneous mixture,

[0626] step B, drying the homogeneous material at a temperature ranging from 60° C. to 100° C. for a period ranging from 10 hours to 24 hours, so as to obtain the catalyst Cu-M / support in the form of a dry homogeneous mixture,

[0627] • An activation step C comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air, so as to obtain said catalyst Cu-M / support.

[0628] According to a specific embodiment, the present invention relates to a method for preparing a catalyst Cu-M / oxide, comprising:

[0629] Step A, impregnating a copper salt and a salt of a metal M dissolved in an aqueous solution (5 mL to 10 mL by volume of water) without additives and surfactants onto an oxide support in powder form, wherein M is selected from Mn, Co, Ni and Fe, with a ratio of the mass of the solution to the mass of the support being 0.6 to 1.0;

[0630] to obtain the catalyst Cu-M / support in the form of a homogeneous mixture,

[0631] step B, drying the homogeneous material at a temperature ranging from 60° C. to 100° C. for a period ranging from 10 hours to 24 hours, so as to obtain the catalyst Cu-M / support in the form of a dry homogeneous mixture,

[0632] • An activation step C comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air, so as to obtain said catalyst Cu-M / support.

[0633] According to a specific embodiment, the present invention relates to a method for preparing a Cu-M / ZrO2 catalyst, comprising:

[0634] Step A, impregnating a copper salt and a salt of a metal M dissolved in an aqueous solution (5 mL to 10 mL by volume of water) without additives and surfactants on a zirconium dioxide support in powder form, wherein M is selected from Mn, Co, Ni and Fe, and the ratio of the mass of the solution to the mass of the support is 0.6 to 1.0;

[0635] To obtain the catalyst Cu-M / ZrO2 in the form of a homogeneous mixture,

[0636] The carrier has a surface area of ​​1 m 2 / g to 250m 2 / g, especially 1m 2 / g to 50m 2 / g, preferably 1m 2 / g to 10m 2 / g,

[0637] and comprising a crystalline phase, which is monoclinic crystallized by X-ray diffraction analysis,

[0638] step B, drying the homogeneous material at a temperature of 60° C. to 100° C. for a period of 10 to 24 hours, so as to obtain the catalyst Cu—M / ZrO 2 in the form of a dry homogeneous mixture,

[0639] • An activation step C comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air to obtain said catalyst.

[0640] According to a specific embodiment, the present invention relates to a method for preparing a Cu-Mn / ZrO2 catalyst, comprising:

[0641] Step A: impregnating a copper salt and a manganese salt dissolved in an aqueous solution (5 mL to 10 mL by volume of water) without additives and surfactants onto a zirconium dioxide support in powder form, with the ratio of the mass of the solution to the mass of the support being 0.6 to 1.0; to obtain a catalyst Cu-Mn / ZrO2 in the form of a homogeneous mixture,

[0642] The carrier has a surface area of ​​1 m 2 / g to 250m 2 / g, especially 1m 2 / g to 50m 2 / g, preferably 1m 2 / g to 10m 2 / g,

[0643] and comprising a crystalline phase, which is monoclinic crystallized by X-ray diffraction analysis,

[0644] step B, drying the homogeneous material at a temperature of 60° C. to 100° C. for a period of 10 to 24 hours, so as to obtain the catalyst Cu—Mn / ZrO 2 in the form of a dry homogeneous mixture,

[0645] • An activation step C comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air to obtain said catalyst.

[0646] According to a specific embodiment, the present invention relates to a method for preparing a Cu-Co / ZrO2 catalyst, comprising:

[0647] Step A: impregnating a copper salt and a cobalt salt dissolved in an aqueous solution (5 mL to 10 mL by volume of water) without additives and surfactants onto a zirconium dioxide support in powder form, with the ratio of the mass of the solution to the mass of the support being 0.6 to 1.0; to obtain a catalyst Cu-Co / ZrO2 in the form of a homogeneous mixture,

[0648] The carrier has a surface area of ​​1 m 2 / g to 250m 2 / g, especially 1m 2 / g to 50m 2 / g, preferably 1m 2 / g to 10m 2 / g,

[0649] and comprising a crystalline phase, which is monoclinic crystallized by X-ray diffraction analysis,

[0650] step B, drying the homogeneous material at a temperature of 60° C. to 100° C. for a period of 10 to 24 hours, so as to obtain the catalyst Cu—Co / ZrO 2 in the form of a dry homogeneous mixture,

[0651] • An activation step C comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air to obtain said catalyst.

[0652] According to a specific embodiment, the present invention relates to a method for preparing a Cu-Ni / ZrO2 catalyst, comprising:

[0653] Step A: impregnating a copper salt and a nickel salt dissolved in an aqueous solution (5 mL to 10 mL by volume of water) without additives and surfactants onto a zirconium dioxide support in powder form, with the ratio of the mass of the solution to the mass of the support being 0.6 to 1.0; to obtain a catalyst Cu-Ni / ZrO2 in the form of a homogeneous mixture,

[0654] The carrier has a surface area of ​​1 m 2 / g to 250m 2 / g, especially 1m 2 / g to 50m 2 / g, preferably 1m 2 / g to 10m 2 / g,

[0655] and comprising a crystalline phase, which is monoclinic crystallized by X-ray diffraction analysis,

[0656] step B, drying the homogeneous material at a temperature of 60° C. to 100° C. for a period of 10 to 24 hours, so as to obtain the catalyst Cu—Ni / ZrO 2 in the form of a dry homogeneous mixture,

[0657] • An activation step C comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air to obtain said catalyst.

[0658] According to a specific embodiment, the present invention relates to a method for preparing a Cu-Fe / ZrO2 catalyst, comprising:

[0659] Step A: impregnating a copper salt and an iron salt dissolved in an aqueous solution (5 mL to 10 mL by volume of water) without additives and surfactants onto a zirconium dioxide support in powder form, with the ratio of the mass of the solution to the mass of the support being 0.6 to 1.0; to obtain a catalyst Cu-Fe / ZrO2 in the form of a homogeneous mixture,

[0660] The carrier has a surface area of ​​1 m 2 / g to 250m 2 / g, especially 1m 2 / g to 50m 2 / g, preferably 1m 2 / g to 10m 2 / g,

[0661] and comprising a crystalline phase, which is monoclinic crystallized by X-ray diffraction analysis,

[0662] step B, drying the homogeneous material at a temperature of 60° C. to 100° C. for a period of 10 to 24 hours, so as to obtain the catalyst Cu—Fe / ZrO 2 in the form of a dry homogeneous mixture,

[0663] • An activation step C comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air to obtain said catalyst.

[0664] According to a specific embodiment, the present invention relates to a method for preparing a Cu-M / γ-Al2O3 catalyst, comprising:

[0665] Step A, impregnating a copper salt and a salt of a metal M dissolved in an aqueous solution (5 mL to 10 mL by volume of water) without additives and surfactants on a γ-Al2O3 alumina support in powder form, wherein M is selected from Mn, Co, Ni and Fe, with a ratio of the mass of the solution to the mass of the support being 0.6 to 1.0;

[0666] To obtain the catalyst Cu-M / γ-Al2O3 in the form of a homogeneous mixture,

[0667] step B, drying the homogeneous material at a temperature of 60° C. to 100° C. for a period of 10 to 24 hours, so as to obtain the catalyst Cu-M / γ-Al2O3 in the form of a dry homogeneous mixture,

[0668] An activation step C, comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air, in order to obtain said catalyst Cu—M / γ-Al 2 O 3 .

[0669] According to a specific embodiment, the present invention relates to a method for preparing a Cu-Mn / γ-Al2O3 catalyst, comprising:

[0670] Step A: impregnating a powdered γ-Al2O3 alumina support with a copper salt and a manganese salt dissolved in an aqueous solution (5 mL to 10 mL by volume of water) without additives and surfactants, with a solution mass to support mass ratio of 0.6 to 1.0;

[0671] To obtain the catalyst Cu-Mn / γ-Al2O3 in the form of a homogeneous mixture,

[0672] step B, drying the homogeneous material at a temperature of 60° C. to 100° C. for a period of 10 to 24 hours, so as to obtain the catalyst Cu—Mn / γ-Al 2 O 3 in the form of a dry homogeneous mixture,

[0673] An activation step C, comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air, to obtain said catalyst Cu—Mn / γ-Al 2 O 3 .

[0674] According to a specific embodiment, the present invention relates to a method for preparing a Cu-Co / γ-Al2O3 catalyst, comprising:

[0675] Step A: impregnating a γ-Al2O3 alumina support in powder form with a copper salt and a cobalt salt dissolved in an aqueous solution (5 mL to 10 mL by volume of water) without additives and surfactants, with a solution mass to support mass ratio of 0.6 to 1.0;

[0676] To obtain the catalyst Cu-Co / γ-Al2O3 in the form of a homogeneous mixture,

[0677] step B, drying the homogeneous material at a temperature of 60° C. to 100° C. for a period of 10 to 24 hours, so as to obtain the catalyst Cu—Co / γ-Al 2 O 3 in the form of a dry homogeneous mixture,

[0678] An activation step C, comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air, to obtain said catalyst Cu—Co / γ-Al 2 O 3 .

[0679] According to a specific embodiment, the present invention relates to a method for preparing a Cu-Ni / γ-Al2O3 catalyst, comprising:

[0680] Step A: impregnating a γ-Al2O3 alumina support in powder form with a copper salt and a nickel salt dissolved in an aqueous solution (5 mL to 10 mL by volume of water) without additives and surfactants, with a solution mass to support mass ratio of 0.6 to 1.0;

[0681] To obtain the catalyst Cu-Ni / γ-Al2O3 in the form of a homogeneous mixture,

[0682] step B, drying the homogeneous material at a temperature of 60° C. to 100° C. for a period of 10 to 24 hours, so as to obtain the catalyst Cu—Ni / γ-Al 2 O 3 in the form of a dry homogeneous mixture,

[0683] An activation step C, comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air, to obtain said catalyst Cu—Ni / γ-Al 2 O 3 .

[0684] According to a specific embodiment, the present invention relates to a method for preparing a Cu-Fe / γ-Al2O3 catalyst, comprising:

[0685] Step A: impregnating a powdered γ-Al2O3 alumina support with a copper salt and an iron salt dissolved in an aqueous solution (5 mL to 10 mL by volume of water) without additives and surfactants, with a solution mass to support mass ratio of 0.6 to 1.0;

[0686] To obtain the catalyst Cu-Fe / γ-Al2O3 in the form of a homogeneous mixture,

[0687] step B, drying the homogeneous material at a temperature of 60° C. to 100° C. for a period of 10 to 24 hours to obtain the catalyst Cu—Fe / γ-Al 2 O 3 in the form of a dry homogeneous mixture,

[0688] An activation step C, comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air, to obtain said catalyst Cu—Fe / γ-Al 2 O 3 .

[0689] According to a particular embodiment, the invention relates to a process for preparing a catalyst according to the invention as defined above, wherein, in step A, the salt of the metal M is a nitrate and / or the copper salt is copper nitrate.

[0690] According to a particular embodiment, the invention relates to a process for preparing a catalyst according to the invention as defined above, wherein, in step A, the support is used in an amount ranging from 1 g to 50 g.

[0691] According to a specific embodiment, the present invention relates to a process for preparing the Cu-M / support catalyst according to the invention as defined above, wherein, in step A, the total mass content of the bimetallic elements copper and metal M is from 0.5% to 25% by weight, based on the total weight of the catalyst.

[0692] According to a specific embodiment, the present invention relates to a process for preparing the Cu-M / support catalyst according to the invention as defined above, wherein, in step A, the total mass content of the bimetallic elements copper and metal M is from 5% to 20% by weight, based on the total weight of the catalyst.

[0693] According to a specific embodiment, the present invention relates to a process for preparing the Cu-M / support catalyst according to the invention as defined above, wherein, in step A, the total mass content of elemental copper is from 1% to 25% by weight, preferably from 1% to 10% by weight, based on the total weight of the catalyst.

[0694] According to a specific embodiment, the present invention relates to a process for preparing the Cu-M / support catalyst according to the invention as defined above, wherein, in step A, the total mass content of elemental metals M is from 1% to 25% by weight, preferably from 1% to 10% by weight, based on the total weight of the catalyst.

[0695] According to a particular embodiment, the invention relates to a process for preparing the Cu-M / support catalyst according to the invention as defined above, wherein, in step A, the weight ratio between metal M and copper varies from 1:1 to 1:10, in particular from 2:10 to 5:10.

[0696] According to a particular embodiment, the invention relates to a process for preparing the catalyst Cu-M / support according to the invention as defined above, wherein, in step B, the homogeneous mixture is dried at 80° C. for 16 hours.

[0697] According to a particular embodiment, the invention relates to a process for preparing the catalyst Cu-M / support according to the invention as defined above, wherein, in step C, the dried homogeneous mixture is calcined at 600° C. for 2 hours.

[0698] According to a specific embodiment, the present invention relates to a method for preparing the catalyst Cu-M / ZrO2 according to the invention as defined above, wherein, in step A, the support used has a specific surface area of ​​1 m 2 / g to 50m 2 / g.

[0699] According to a particular embodiment, the present invention relates to a process for preparing a catalyst according to the invention as defined above, wherein, in step A, the support for the catalyst Cu-M / ZrO2 has a specific surface area of ​​1 m 2 / g to 10m 2 / g, preferably 5m 2 / g to 7m 2 / g.

[0700] According to a particular embodiment, the invention relates to a process for preparing the catalyst Cu-M / ZrO2 according to the invention as defined above, wherein, in step A, the support used has a crystalline phase representing 50% to 90% of the total weight of the catalyst.

[0701] According to a particular embodiment, the invention relates to a process for preparing the catalyst Cu-M / ZrO2 according to the invention as defined above, wherein, in step A, the support used comprises baddeleyite.

[0702] According to a specific embodiment, the present invention relates to a process for preparing the catalyst Cu-M / ZrO2 according to the invention as defined above, wherein, in step A, the support used comprises baddeleyite having a grain size of 15 nm to 100 nm, preferably 15 nm to 50 nm, and optionally comprising impurities of hafnium (Hf), rhenium (Re) and silicon (Si).

[0703] According to a particular embodiment, the invention relates to a process for preparing the Cu—Co / ZrO 2 catalyst according to the invention as defined above, wherein, in step A, the support is in the form of microparticles ranging from 1 μm to 500 μm.

[0704] Catalyst prepared according to the method of the present invention

[0705] A fifth object of the present invention relates to a supported bimetallic catalyst having the formula Cu-M / support, said catalyst comprising copper and metal M on a support, said M being selected from the group consisting of Mn, Co, Ni and Fe, said catalyst being obtainable by the method for preparing the catalyst as defined above.

[0706] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-M / oxide, said catalyst comprising copper and metal M on an oxide support, said M being selected from Mn, Co, Ni and Fe, said catalyst being obtainable by the method for preparing the catalyst as defined above.

[0707] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-M / ZrO2, comprising copper and a metal M on a zirconium dioxide support, wherein M is selected from the group consisting of Mn, Co, Ni and Fe, and the catalyst can be obtained by the method for preparing the catalyst as defined above.

[0708] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-Mn / ZrO2, said catalyst comprising copper and manganese on a zirconium dioxide support, said catalyst being obtainable by the method for preparing the catalyst as defined above.

[0709] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-Co / ZrO2, said catalyst comprising copper and cobalt on a zirconium dioxide support, said catalyst being obtainable by the method for preparing the catalyst as defined above.

[0710] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-Ni / ZrO2, said catalyst comprising copper and nickel on a zirconium dioxide support, said catalyst being obtainable by the method for preparing the catalyst as defined above.

[0711] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu—Fe / ZrO 2 , said catalyst comprising copper and iron on a zirconium dioxide support, said catalyst being obtainable by the method for preparing the catalyst as defined above.

[0712] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-M / γ-Al2O3, comprising copper and metal M on a γ-Al2O3 alumina support, wherein M is selected from the group consisting of Mn, Co, Ni and Fe, and the catalyst can be obtained by the method for preparing the catalyst as defined above.

[0713] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-Mn / γ-Al2O3, comprising copper and manganese on a γ-Al2O3 alumina support, obtainable by the method for preparing the catalyst as defined above.

[0714] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-Co / γ-Al2O3, comprising copper and cobalt on a γ-Al2O3 alumina support, obtainable by the method for preparing the catalyst as defined above.

[0715] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-Ni / γ-Al2O3, comprising copper and nickel on a γ-Al2O3 alumina support, obtainable by the method for preparing the catalyst as defined above.

[0716] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst having the formula Cu-Fe / γ-Al2O3, said catalyst comprising copper and iron on a γ-Al2O3 alumina support, said catalyst being obtainable by the method for preparing the catalyst as defined above.

[0717] Characteristics of catalysts under reducing atmosphere

[0718] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst prepared according to the invention and as defined above,

[0719] The catalyst is analyzed by temperature-programmed reduction (TPR) in a dihydrogen reducing atmosphere at a temperature range of 30°C to 900°C, characterized in that the reduction temperature of metallic copper with an oxidation degree (0) is in the range of 150°C to 250°C, in particular 180°C to 220°C.

[0720] Advantageously, at a temperature above the reduction temperature of metallic copper, in particular at least 10° C. higher, 80% to 100%, in particular 95% to 100%, preferably 100%, of the copper atoms are in metallic form.

[0721] Advantageously, at a temperature above the reduction temperature of metallic copper, in particular at least 10° C. above, more than 80%, in particular 80% to 100%, preferably 100%, of the metal M atoms are in oxidized form, ie the degree of oxidation is greater than zero.

[0722] Advantageously, at a temperature above the reduction temperature of the metallic copper, in particular at least 10° C. above, 0% to 20%, in particular 0% to 10%, preferably less than 5% of the metal M atoms are in metallic form with zero oxidation degree.

[0723] Advantageously, the metal M is Co and 80% to 100% of the cobalt atoms are in oxidized form or at least 10%, preferably 20%, of the cobalt atoms are in metallic form at a temperature above said reduction temperature of metallic copper, in particular at least 10°C above.

[0724] Advantageously, at a temperature above said reduction temperature of metallic copper, in particular at least 10° C. above, the metal M is Mn and 95% to 100%, preferably 100%, of the manganese atoms are in oxidized form, ie the degree of oxidation is greater than zero.

[0725] Advantageously, at a temperature above said reduction temperature of metallic copper, in particular at least 10° C. above, the metal M is Fe and 95% to 100%, preferably 100%, of the iron atoms are in oxidized form, ie the degree of oxidation is greater than zero.

[0726] Advantageously, the metal M is Ni and 95% to 100%, preferably 100%, of the nickel atoms are in oxidized form at a temperature above said reduction temperature of metallic copper, in particular at least 10°C above.

[0727] According to a particular embodiment, the present invention relates to a supported bimetallic catalyst as defined above, wherein said catalyst is analyzed by performing a temperature-programmed reduction (TPR) in a dihydrogen reducing atmosphere at a temperature ranging from 30°C to 900°C, characterized in that the reduction temperature of metallic copper with a degree of oxidation (0) ranges from 150°C to 250°C,

[0728] In particular, at a temperature at least 10° C. higher than the reduction temperature of said metallic copper as analyzed by TPR,

[0729] 80% to 100%, preferably 100%, of the copper atoms are in metallic form,

[0730] From 80% to 100%, preferably 100%, of the atoms of the metal M are in oxidized form.

[0731] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst as defined above, wherein the catalyst is analyzed by performing temperature-programmed reduction (TPR) in a reducing atmosphere of a 5 vol% H2 flow in argon (especially at 30 mL / min) in a temperature range of 30°C to 900°C, especially at a heating rate of 5°C / min, characterized in that the reduction temperature of metallic copper with degree of oxidation (0) is in the range of 150°C to 250°C.

[0732] Advantageously, before said analysis, the catalyst is pretreated in an inert atmosphere, in particular under helium, at 200°C.

[0733] According to a specific embodiment, the present invention relates to a supported bimetallic catalyst as defined above, wherein, under a reducing atmosphere of hydrogen, at a pressure of 2 MPa to 10 MPa and a temperature of 150° C. to 250° C. (in particular 180° C. to 220° C.), the catalyst comprises:

[0734] 80% to 100%, in particular 95% to 100%, preferably 100%, of metallic copper atoms Cu(0), and

[0735] - 80% to 100% of atoms of metal M in a degree of oxidation greater than zero, preferably said metal M not being in metallic form.

[0736] Advantageously, 95%, preferably 100%, of the copper atoms are in metallic form.

[0737] Advantageously, 80% to 100%, in particular 95% to 100%, preferably 100%, of the atoms of the metal M are in oxidized form with a degree of oxidation greater than zero.

[0738] Advantageously, 0% to 20%, in particular 0% to 15%, preferably less than 20%, of the cobalt atoms are in metallic form.

[0739] Advantageously, 95%, preferably 100%, of the manganese atoms are in oxidized form with a degree of oxidation greater than zero.

[0740] Advantageously, 95%, preferably 100%, of the iron atoms are in oxidized form with a degree of oxidation greater than zero.

[0741] Advantageously, 95%, preferably 100%, of the nickel atoms are in oxidized form.

[0742] Catalyst in activated form

[0743] Another object of the present invention relates to an activated supported bimetallic catalyst having the formula Cu-M / support, said catalyst comprising copper and a metal M selected from the group consisting of Mn, Co, Ni and Fe on the surface of the support, wherein

[0744] 80% to 100%, in particular 95% to 100%, preferably 100%, of the copper atoms are in the zero oxidation state Cu(0), and

[0745] - 80% to 100%, in particular 95% to 100%, preferably 100% of the metal M atoms

[0746] At a degree of oxidation greater than zero.

[0747] "Activated catalyst" refers to a catalyst in its activated form, ie the form of the catalyst during a chemical reaction catalyzed by the catalyst, ie the form comprising the catalytic species that initiates catalysis.

[0748] Advantageously, more than 95%, preferably 100%, of the copper atoms are in metallic form.

[0749] Advantageously, 80% to 100%, in particular 95% to 100%, preferably 100%, of the cobalt atoms are in oxidized form with a degree of oxidation greater than zero.

[0750] Advantageously, more than 95%, preferably 100%, of the manganese atoms are in oxidized form with a degree of oxidation greater than zero.

[0751] Advantageously, more than 95%, preferably 100%, of the iron atoms are in oxidized form with a degree of oxidation greater than zero.

[0752] Advantageously, more than 95%, preferably 100%, of the nickel atoms are in oxidized form.

[0753] Use of catalyst for ethylene glycol hydrogenolysis or biomass depolymerization

[0754] Another object of the present invention relates to the use of a catalyst of the formula Cu-M / support, wherein M represents Mn, Co, Ni or Fe, for the hydrogenolysis of ethylene glycol, the catalyst comprising copper and a metal M on a support, the metal M being chosen from manganese, cobalt, nickel and iron.

[0755] According to a particular embodiment, the invention relates to the use of a catalyst having the formula Cu—Co / ZrO 2 as defined above, comprising copper and cobalt on a zirconium dioxide support, for the hydrogenolysis of ethylene glycol.

[0756] Another object of the present invention relates to the use of the catalyst Cu-M / support as defined above according to the invention for the hydrogenolysis of ethylene glycol.

[0757] The inventors have surprisingly observed that the Cu-M / support catalyst according to the invention makes it possible to catalyze the hydrogenation of oxamide or oxamate to ethylene glycol, and also to catalyze the hydrogenolysis of ethylene glycol present in the mixture resulting from the hydrogenation of oxamide or oxamate. Varying the parameters of the conditions (e.g., temperature) allows for regulation, in particular by promoting the hydrogenation of oxamide or oxamate.

[0758] For the purposes of the present invention, "hydrogenolysis" refers to a reaction in which at least one carbon-carbon (CC) or carbon-heteroatom covalent bond (eg, carbon-oxygen bond) is broken by the action of hydrogen.

[0759] Another object of the present invention relates to a method for hydrogenolysis of ethylene glycol, comprising:

[0760] o A step of contacting ethylene glycol with a heterogeneous supported bimetallic catalyst as defined above having the formula Cu-M / support, said catalyst comprising copper and a metal M selected from the group consisting of Mn, Co, Ni and Fe on a support, in the presence of hydrogen.

[0761] According to a particular embodiment, the present invention relates to a process for the hydrogenolysis of ethylene glycol as defined above, comprising:

[0762] o Contacting the following to obtain a reaction medium that can be pressurized:

[0763] -ethylene glycol,

[0764] - dihydrogen, in particular at 20 bar to 100 bar, preferably 60 bar,

[0765] - the supported catalyst having the formula Cu-M / support, wherein M represents Mn,

[0766] Co, Ni or Fe, the catalyst comprises copper and a metal M on a support, the metal M being selected from manganese, cobalt, nickel and iron,

[0767] - in particular zirconium dioxide or gamma-aluminum oxide,

[0768] - optionally a solvent, in particular tetrahydrofuran (THF),

[0769] - optionally a base, in particular potassium tert-butoxide (KOtBu),

[0770] o optionally, heating the reaction medium,

[0771] Degradation of ethylene glycol is thereby achieved by breaking at least one carbon-carbon or carbon-oxygen covalent bond.

[0772] Another object of the present invention relates to the use of a catalyst of formula Cu-M / support, wherein M represents Mn, Co, Ni or Fe, for depolymerizing biomass by hydrogenolysis of ethylene glycol groups present in the compounds constituting said biomass, said catalyst comprising copper and a metal M chosen from manganese, cobalt, nickel and iron, on a support.

[0773] According to a particular embodiment, the invention relates to the use of a catalyst of formula Cu—Co / ZrO 2 as defined above, comprising copper and cobalt on a zirconium dioxide support, for depolymerizing biomass by hydrogenolysis of ethylene glycol groups present in the compounds constituting said biomass.

[0774] Another object of the present invention relates to the use of the catalyst Cu-M / support as defined above according to the invention for depolymerizing biomass.

[0775] The inventors have unexpectedly observed that, based on ethylene glycol as a model compound, the catalyst Cu-M / support according to the invention can catalyze the hydrogenolysis reaction of diol groups present in carbohydrate molecules contained in biomass by breaking carbon-carbon (CC) or carbon-oxygen (CO) bonds.

[0776] For the purposes of this invention, "biomass" refers to organic matter derived from plants (including microalgae), animals, bacteria, or fungi that can be used as an energy source (bioenergy). Biomass includes carbohydrate molecules or polyols, in which diol groups -CHOH-CHOH-, i.e., ethylene glycol groups, are present, containing covalent C-C and C-O bonds.

[0777] For the purposes of the present invention, "depolymerizing biomass" refers to the act of breaking carbon-carbon (CC) or carbon-heteroatom (CX) covalent bonds (eg, carbon-oxygen (CO) bonds) of carbohydrate molecules contained in the biomass.

[0778] Another object of the present invention relates to a method for degrading biomass, comprising:

[0779] o A hydrogenolysis step of C—C and C—O bonds in diol groups contained in carbohydrate molecules contained in the biomass in the presence of a supported bimetallic catalyst of formula Cu—M / support as defined above, comprising copper and a metal M on a support, in particular an oxide, preferably zirconium dioxide or gamma-alumina, said M being chosen from Mn, Co, Ni and Fe. BRIEF DESCRIPTION OF THE DRAWINGS

[0780] The following examples and figures illustrate the present invention without limiting its scope.

[0781] Figure 1 An X-ray powder diffraction pattern of supported ZrO 2 calcined at 600° C. for 2 hours is shown.

[0782] Figure 2 The X-ray powder diffraction pattern of the catalyst Cu(10%)Co(5%) / ZrO2 prepared with ZrO2 as carrier is shown. The specific surface area of ​​the catalyst is about 5m 2 / g.

[0783] Figure 3 Shown is a scanning electron microscopy image of supported ZrO2 calcined at 600°C for 2 hours.

[0784] Figure 4 The scanning electron microscopy image of the catalyst Cu(10%)Co(5%) / ZrO2 calcined at 600°C for 2 hours is shown. The specific surface area of ​​the catalyst is about 5 m 2 / g.

[0785] Figure 5 The scanning electron microscopy image of the catalyst Cu(10%)Mn(5%) / ZrO2 calcined at 600°C for 2 hours is shown. The specific surface area of ​​the catalyst is about 5m 2 / g.

[0786] Figure 6 The scanning electron microscopy image of the catalyst Cu(10%)Mn(5%) / γ-Al2O3 calcined at 600°C for 2 hours is shown. The specific surface area of ​​the catalyst is about 150 m 2 / g.

[0787] Figure 7Shown are the X-ray photoelectron spectra of the catalyst Cu-Co / ZrO2 calcined at 600°C for 2 hours, having a composition of 10% by weight of Cu and 5% by weight of Co relative to the total weight of the catalyst (spectrum A), and the X-ray photoelectron spectrum of the support ZrO2 used for the preparation of the catalyst calcined at 600°C for 2 hours (spectrum B).

[0788] Figure 8 Shown are the X-ray photoelectron spectra of the catalyst Cu-Mn / ZrO2 calcined at 600°C for 2 hours, having a composition of 10% by weight of Cu and 5% by weight of Mn relative to the total weight of the catalyst (spectrum C), and the X-ray photoelectron spectrum of the catalyst Cu-Mn / γ-Al2O3 calcined at 600°C for 2 hours, having a composition of 10% by weight of Cu and 5% by weight of Mn relative to the total weight of the catalyst (spectrum D).

[0789] Figure 9 The X-ray photoelectron spectra of copper Cu2p of the catalysts Cu(10%)Mn(5%) / ZrO2 and Cu(10%)Mn(5%) / γ-Al2O3 are shown.

[0790] Figure 10 The X-ray photoelectron spectra of manganese Mn2p of the catalysts Cu(10%)Mn(5%) / ZrO2 and Cu(10%)Mn(5%) / γ-Al2O3 are shown.

[0791] Figure 11 The analytical curves of programmed temperature reduction (H2-TPR) of the following catalysts prepared under dihydrogen flow in the temperature range of 100°C to 500°C are shown: Cu(10%)Co(5%) / γ-Al2O3 in part (a), Cu(10%)Mn(5%) / γ-Al2O3 in part (b), Cu(10%)Co(5%) / ZrO2 in part (c), and Cu(10%)Mn(5%) / ZrO2 in part (e).

[0792] Example

[0793] Example 1 - Materials and Methods

[0794] Two different supports were used to prepare the catalyst, one made of zirconium dioxide ZrO2 and the other made of aluminum oxide (γ-Al2O3).

[0795] The specific surface area is 5m 2 / g to 7m 2 / g zirconium dioxide support ZrO2, provided by Sterm Chemicals (15 Rue de l'Atome, 67800 Bischheim), reference number 93-4013.

[0796] The zirconium dioxide support ZrO2 supplied by Sterm Chemicals consists of approximately 97% by weight zirconium dioxide, 1.86% by weight hafnium dioxide (HfO2), and trace amounts of silicon dioxide (SiO2) and yttrium oxide (Y2O3).

[0797] The γ-Al2O3 support was supplied by Strem Chemicals (15 Rue del'Atome, 67800 Bischheim) under the reference number 13-2525 and had a specific surface area of ​​approximately 185 m 2 / g, and the pore volume is 0.43cc / g.

[0798] SiO2 supports (40 mm-63 mm) were supplied by VWR chemicals, reference number 154425P.

[0799] Copper nitrate Cu(NO3)2.3H2O, cobalt nitrate (Co(NO3)2.3H2O), manganese nitrate, nickel nitrate and iron nitrate were provided by Fischer.

[0800] The autoclave was supplied by Parr Instrument Company.

[0801] Example 2 - General Procedure for Preparation of Heterogeneous Catalysts Cu-M / Support

[0802] A nitrate of a metal M (M selected from Mn, Co, Ni, and Fe) and copper nitrate Cu(NO3)2.3H2O were dissolved in a minimum volume of demineralized water (5 mL to 10 mL) to form a solution. This solution containing the metal precursor was added to an appropriate amount of support and mixed at room temperature until a homogeneous material was obtained. The material was then dried at 80°C for 16 hours and subsequently calcined at 600°C in air for 2 hours to obtain the catalyst.

[0803] Table 1 below shows the preparation conditions of the catalysts Cu-M / ZrO2 and Cu-M / γ-Al2O3 prepared according to Example 2.

[0804] Table 1: Composition of the prepared catalysts Cu-M / ZrO2 and Cu-M / γ-Al2O3.

[0805]

[0806]

[0807] Example 3 - General Procedure for Heterogeneous Catalysis of Oxamide Hydrogenation in a 450 mL Reactor

[0808] A heterogeneous catalyst based on copper (4 mmol Cu) and a metal M (described M is selected from Mn, Co, Ni and Fe) on a support, oxalamide (10 mmol), potassium tert-butoxide (KOtBu) (2 mmol) as a base and toluene or THF (40 mL to 75 mL) as a solvent were introduced into a 450 mL Parr autoclave equipped with a magnetic stirrer. The reactor was sealed and the reaction mixture was purged three times with nitrogen (5 bar) and twice with hydrogen (5 bar).

[0809] The autoclave is then pressurized with 60 bar of hydrogen.The reaction medium is then stirred at a temperature between 180° C. and 200° C. for 8 hours, 15 hours or 24 hours.

[0810] When the reaction was complete, the autoclave was returned to room temperature, decompressed, and purged with nitrogen (5 bar) three times.

[0811] The finally obtained mixture was diluted, and an internal standard (mesitylene) was added to calculate the yield by using GC-MS.

[0812] Example 4 - Tests using catalyst Cu-M / support

[0813] The test was carried out according to the following reaction scheme according to Example 3:

[0814]

[0815] Table 2 shows the conditions for the hydrogenation experiments carried out using the catalyst Cu-M / support prepared according to Example 2. The hydrogenation yield was calculated using GC-MS, using mesitylene as an internal standard. The conversion of oxalamide corresponds to the amount of substrate consumed during the reaction.

[0816] Table 2: Conditions of hydrogenation experiments with bimetallic catalyst Cu-M / support and the results obtained.

[0817]

[0818]

[0819] Example 5 - Experiments carried out - Influence of hydrogenation process parameters

[0820] A) Monometallic Catalysts

[0821] Table 3 reports the conditions for hydrogenation experiments using the monometallic catalysts Cu / ZrO2, Co / ZrO2, and Ni / ZrO2, respectively. The hydrogenation yields were calculated using GC-MS, using mesitylene as an internal standard. The conversion of oxalamide corresponds to the amount of substrate consumed during the reaction.

[0822] These results indicate that monometallic catalysts are not capable of hydrogenating oxalamide to ethylene glycol.

[0823] Table 3: Conditions of hydrogenation experiments using monometallic catalysts and the results obtained.

[0824]

[0825] B) Effect of temperature and reaction time

[0826] Table 4 reports the conditions of the hydrogenation experiments carried out using the Cu-Co / ZrO2 catalyst prepared according to Example 2. The conversion of oxalamide (corresponding to the amount of substrate consumed during the reaction) was calculated by using GC-MS, using mesitylene as an internal standard.

[0827] Table 4: Conditions of hydrogenation tests carried out using the Cu-Co / ZrO2 catalyst and the results obtained.

[0828]

[0829]

[0830] C) Effect of alkali

[0831] The conditions of the hydrogenation experiments carried out without the introduction of a base using the catalyst Cu-Co / ZrO2 are reported in Table 5. The yield and conversion of oxalamide were calculated by using GC-MS, with mesitylene used as an internal standard.

[0832] Table 5: Conditions and results obtained for hydrogenation tests carried out without the introduction of a base using the catalyst Cu—Co / ZrO 2 .

[0833]

[0834] Example 6 BET analysis of catalyst Cu-M / support

[0835] Table 6 below shows the average specific surface area of ​​the catalysts Cu(10%)-Co(5%) / ZrO2, Cu(10%)-Mn(5%) / ZrO2 and Cu(10%)-Mn(5%) / γ-Al2O3 prepared according to Example 2 after calcination at 600°C for 2 hours, as analyzed by BET.

[0836] Table 6: Average specific surface area of ​​the catalysts by BET

[0837] Compound <![CDATA[Average specific surface area (m 2 / g)]]> <![CDATA[ZrO2]]> 6.11 <![CDATA[Co(5%)Cu(10%)ZrO2]]> 5.44 <![CDATA[Cu(10%)-Mn(5%) / ZrO2]]> 5.63 <![CDATA[Cu(10%)-Mn(5%) / γ-Al2O3]]> 152.14

[0838] Example 7: Structural Analysis

[0839] A. Phase Analysis

[0840] The X-ray powder diffractogram of the material (catalyst or support) was carried out using a MINIFLEXII diffractometer from the Rigaku brand, which emits X-ray radiation (wavelength Kα) through a tube and a copper source. ).

[0841] Figure 1 The obtained calcined at 600 ° C for 2 hours has a 5.4 m 2 / g of the catalyst Co (5%) Cu (10%) / ZrO2 RX diffraction pattern.

[0842] Figure 2 The obtained calcined at 600 ° C for 2 hours has a 6.1m 2 RX diffraction pattern of the carrier ZrO2 used with a specific surface area of ​​1.577 W / g.

[0843] The utilization results of the different diffraction patterns obtained are shown in Tables 7 to 10 below:

[0844] - support ZrO2 (A) in Table 7,

[0845] - the catalyst Cu(10%)Co(5%) / ZrO2 in Table 8,

[0846] - the catalyst Cu(10%)Mn(5%) / ZrO2 in Table 9,

[0847] - Catalyst Cu(10%)Mn(5%) / γ-Al2O3 in Table 10.

[0848] Table 7: Phase analysis in calcined ZrO2 support

[0849] Sample reference Identified crystalline phases ICDD table <![CDATA[ZrO2]]> <![CDATA[Baddeleyite–ZrO2]]> 00-037-1484

[0850] Table 8: Phase analysis in catalyst Co(5%)Cu(10%) / ZrO2

[0851]

[0852] Table 9: Phase analysis in catalyst Cu(10%)Mn(5%) / ZrO2

[0853]

[0854] Table 10: Phase analysis in catalyst Cu(10%)Mn(5%) / γ-Al2O3

[0855]

[0856] Zirconium dioxide ZrO2 catalyst

[0857] The diffraction pattern of the catalyst on zirconium dioxide showed the presence of a crystalline phase.

[0858] XRD analysis indicated that the crystalline phase of baddeleyite (ZrO2) existed in the catalytic samples ZrO2, Cu(10%)Co(5%) / ZrO2 and Cu(10%)Mn(5%) / ZrO2.

[0859] The diffraction pattern of the sample Co(5%)Cu(10%) / ZrO2 reveals the presence of two additional crystalline phases of copper(I) oxide Cu2O and copper(II) oxide CuO with weak features.

[0860] The diffraction pattern of the sample Cu(10%)Mn(5%) / ZrO2 reveals the presence of a crystalline phase of baddeleyite in most cases, and copper oxide CuO and manganese copper oxide CuMn2O4 in a few cases.

[0861] Catalyst Cu(10%)Mn(5%) / γ-Al2O3 on alumina

[0862] The diffraction pattern of the sample Cu(10%)Mn(5%) / γ-Al2O3 reveals the presence of a crystalline phase of aluminum oxide close to aluminum oxide, as well as a crystalline phase of copper oxide CuO, a crystalline phase of manganese copper oxide CuMn2O4 and a crystalline phase of manganese aluminum oxide.

[0863] B. Crystallinity-Microstructure: Grain Size Analysis

[0864] Grain size

[0865] The crystallinity of a material is characterized by its grain size.

[0866] In order to compare the different ZrO2 supports of the catalysts, a qualitative evaluation of the crystallite size was performed.

[0867] The grain size is evaluated according to the following Scherrer formula:

[0868]

[0869] The peak width at half height was estimated using ImageJ processing software (developed by the National Institutes of Health).

[0870] The grain sizes calculated from the diffraction pattern of the catalyst Co(5%)Cu(10%) / ZrO2 are shown in Table 11 below:

[0871] Table 11: Grain size

[0872] refer to Grain size (nm) Cat A <![CDATA[Cu(10%)Co(5%) / ZrO2]]> 21.2nm

[0873] Example 8 - Morphological and Compositional Analysis

[0874] Figures 3 to 6 The SEM images in were taken using a Zeiss SEM-FEG scanning microscope with pressure control, which enables the observation of materials with low or no electrical conductivity without any specific preparation.

[0875] The samples were stabilized on carbon adhesive paper to enable SEM observation. It should therefore be noted that the content of elemental carbon may be related to the use of the latter.

[0876] The results of SEM observation and EDX analysis are summarized as follows.

[0877] Calcinated support ZrO2

[0878] right Figure 3 Observation of the SEM images in the

[15] reveals the presence of multiple particle populations (rounded, spherical, and angular morphologies). The predominant population has a rounded morphology, similar to that of the Co(5%)Cu(10%) / ZrO2 sample. These particles are primarily composed of zirconium (Zr), oxygen (O), and carbon (C), with trace amounts of rhenium (Re), hafnium (Hf), and silicon (Si).

[0879] The minor group has a spherical morphology and is composed mainly of zirconium (Zr), oxygen (O) and carbon (C), with small amounts of hafnium (Hf) and rhenium (Re) and trace amounts of silicon (Si).

[0880] EDX spectroscopy was used to quantify two regions of the particles of the support calcined at 600° C. for two hours. The results are shown in Table 12 as weight percent.

[0881] Table 12: Chemical composition of supported ZrO2 by EDX

[0882]

[0883] Catalyst Co(5%)Cu(10%) / ZrO2

[0884] right Figure 4Observation of the SEM images in [ 1 ] revealed the presence of a cluster of particles with a rounded morphology, similar to the calcined ZrO2 support. These particles are primarily composed of zirconium (Zr), copper (Cu), oxygen (O), carbon (C), and cobalt (Co), with small amounts of hafnium (Hf), rhenium (Re), and trace amounts of silicon (Si). EDX spectroscopy was used to quantify the area of ​​these particles. The results, expressed as mass percentages, are shown in Table 13.

[0885] Table 13: Chemical composition of the catalyst Co(5%)Cu(10%) / ZrO2 by EDX

[0886]

[0887]

[0888] Catalyst Cu(10%)Mn(5%) / ZrO2

[0889] right Figure 5 Observation of the SEM images in the [ 14 ] revealed the presence of a cluster of particles with a rounded morphology in the form of aggregates, similar to the calcined ZrO2 support. These particles are primarily composed of zirconium (Zr), copper (Cu), oxygen (O), and manganese (Mn), with small amounts of hafnium (Hf) and rhenium (Re). EDX spectroscopy was used to quantify the area of ​​these particles. The results, expressed as mass percentages, are shown in Table 14.

[0890] SEM observations were also performed with backscattered electrons and did not show any differences in the chemical contrast of the particles.

[0891] Table 14: Chemical composition of the catalyst Cu(10%)Mn(%) / ZrO2 according to EDX

[0892] element Quantification by EDX spectroscopy (wt%) C 5.81 O 25.80 Mn 5.79 Cu 10.93 Zr 49.35 Hf 1.40 Re 0.92 total 100.00

[0893] Catalyst Cu(10%)Mn(5%) / γ-Al2O3

[0894] right Figure 6 Observation of the SEM images in [ 15 ] revealed the presence of a cluster of particles having a rounded morphology of varying sizes. The entire cluster was covered with very small particles having a needle-like morphology. These particles were primarily composed of aluminum (Al), copper (Cu), oxygen (O), and manganese (Mn). EDX spectroscopy was used to quantify the area of ​​these particles. The results, expressed as mass percentages, are shown in Table 15.

[0895] SEM observations were also performed with backscattered electrons and did not show any differences in the chemical contrast of the particles.

[0896] Table 15: Chemical composition of the catalyst Cu(10%)Mn(5%) / γ-Al2O3 by EDX

[0897] element Quantification by EDX spectroscopy (wt%) C 4.87 O 40.53 Al 37.89 Mn 5.66 Cu 11.05

[0898] Example 9: Composition Analysis by ICP-AES

[0899] The compositions of the catalysts Cu(10%)Mn(%) / ZrO2 and Cu(10%)Mn(5%) / γ-Al2O3 were analyzed by ICP-AES. The results are reported in Tables 16 and 17, respectively.

[0900] The sample was mineralized in a solution of 2 mL of nitric acid HNO3 and 1 mL of hydrofluoric acid HF at 100°C for 2 hours.

[0901] Table 16: Chemical composition of catalyst Cu(10%)Mn(%) / ZrO2 by ICP-AES

[0902] element Content (weight %) Mn 4.59 Zr 58.91 Cu 9.91

[0903] Table 17: Chemical composition of catalyst Cu(10%)Mn(5%) / γ-Al2O3 by ICP-AES

[0904] element Content (weight %) Mn 4.57 Al 43.78 Cu 9.97

[0905] Example 10: Surface analysis by XPS

[0906] The analyses were performed using a PHIQUANTES photoemission spectrometer equipped with a monochromatic X-ray source (aluminum Ka line), a chromium X-ray source for hard XPS, a charge neutralization system for electrically insulating samples, and a hemispherical electron analyzer.

[0907] XPS analysis was performed on the catalyst Co(5%)Cu(10%) / ZrO2 calcined at 600°C for 2 hours and the support ZrO2 sample calcined at 600°C for 2 hours.

[0908] XPS spectra show that Figure 7 middle.

[0909] A. Quantification of the outermost surface area

[0910] The quantification of the outermost surface area of ​​the two samples of calcined ZrO2 and Co(5%)Cu(10%) / ZrO2 is shown in Table 18 below, the quantification being expressed as mass percentage.

[0911] Table 18: Outermost surface chemical composition of calcined ZrO2 and Co(5%)Cu(10%) / ZrO2 by XPS

[0912] atom <![CDATA[Co(5%)Cu(10%)ZrO2(%)]]> <![CDATA[ZrO2(%)]]> Oxygen (O) 34.96 39.74 Zirconium (Zr) 44.53 54.11 Cobalt (Co) 5.71 / Copper (Cu) 11.13 /

[0913] Both samples have low carbon content, mainly from atmospheric pollution.

[0914] The sample Co(5%)Cu(10%)ZrO2 consists of zirconium (Zr), oxygen (O), copper (Cu), cobalt (Co), and trace amounts of silicon (Si) and sodium (Na).

[0915] Sample ZrO2 consists of zirconium (Zr) and oxygen (O) with trace amounts of silicon (Si) and sodium (Na).

[0916] The quantification of the outermost surface area of ​​the two samples of Cu(10%)Mn(5%) / ZrO2 and Cu(10%)Mn(5%) / γ-Al2O3 is shown in Table 19 below, and the quantification is expressed as a mass percentage.

[0917] Table 19: Outermost surface chemical composition of Cu(10%)Mn(5%) / ZrO2 and Cu(10%)Mn(5%) / γ-Al2O3 by XPS

[0918] atom <![CDATA[Cu(10%)Mn(5%) / ZrO2]]> <![CDATA[Cu(10%)Mn(5%) / γ-Al2O3]]> Carbon (C) 7.21 3.38 Oxygen (O) 61.51 59.64 Zirconium (Zr) 16.93 / aluminum / 30.59 manganese 7.53 3.85 Copper (Cu) 1.35 2.54 Silicon (Si) 2.72 / Sodium(Na) 2.33 / Hafnium (Hf) 0.42 /

[0919] Both samples have low carbon content, mainly from atmospheric pollution.

[0920] On the outermost surface, the sample Cu(10%)Mn(5%) / ZrO2 is mainly composed of zirconium (Zr), oxygen (O), and manganese (Mn).

[0921] The sample Cu(10%)Mn(5%) / γ-Al2O3 is composed primarily of aluminum (Al) and oxygen (O). B. Determination of the Chemical Environment of Calcinated ZrO2 and Co(5%)Cu(10%) / ZrO2 The results of Gaussian deconvolution of the spectra are shown in Table 20 below:

[0922] Table 20: Results of XPS analysis

[0923]

[0924] C1s spectrum:

[0925] For all samples, the deconvolution of the C1s carbon spectra has two components:

[0926] The main component at 285.0 eV is characterized by C—C and C—H bonds. These bonds originate from air contamination.

[0927] The component at -288.40 eV is characterized by CO and C=O bonds. These bonds also represent surface contamination.

[0928] O1s spectrum:

[0929] For all samples, the deconvolution of the oxygen O1s spectrum has two components:

[0930] - The major component at 531.0 eV is typically characterized as an oxide.

[0931] The component at -531.2 eV is characterized by transition metal oxides.

[0932] Si2p spectrum:

[0933] For all samples, the deconvolution of the Si2p silicon spectrum has two components:

[0934] - The main component at 103.3 eV is characterized by silicon oxide SiO x .

[0935] The component at -102.0 eV is characterized by silicon oxide SiO2.

[0936] It should be noted that the characteristic composition of cobalt(II) oxide CoO is similar to that of SiO x The components are at the same energy.

[0937] Na1s spectrum:

[0938] For all samples, deconvolution of the sodium Na1s spectra revealed a single component characteristic of air pollution.

[0939] Cu2p3 / 2 spectrum:

[0940] For the sample Co(5wt%)Cu(10wt%)ZrO2, the deconvolution of the copper 2p3 / 2 spectrum has two components:

[0941] - The main component at 934.0 eV is characterized by copper (II) oxide CuO.

[0942] The two strong satellite components at 943.5 eV and 963.5 eV are characterized by Cu 2+ ions and is therefore characterized as copper (II) oxide CuO.

[0943] The -932.6 eV component is characterized by metallic copper or copper (I) oxide, Cu2O.

[0944] Co2p3 / 2 spectrum:

[0945] For the sample Co(5%)Cu(10%)ZrO2, the spectrum of cobalt 2p3 / 2 presents characteristic components of cobalt(III) oxide Co2O3 and cobalt(II) oxide CoO as well as cobalt(II) hydroxide Co(OH)2.

[0946] High-resolution XPS spectrum of zirconium 3d5 / 2

[0947] XPS analysis revealed that for all samples, zirconium oxide (ZrO2) was predominantly present, along with trace amounts of silicon oxides (SiO2 and SiO x ) and the presence of surface contamination (carbon and sodium).

[0948] Sample Co(5%)Cu(10%) / ZrO2 shows the additional presence of copper in two oxidized forms: CuO and Cu2O. XPS analysis also reveals that for this sample, cobalt is present in the form of cobalt hydroxide Co(OH)2, cobalt(II) oxide CoO, or cobalt(III) oxide Co2O3.

[0949] C. Determination of the Chemical Environment of the Catalysts Cu(10%)Mn(5%) / ZrO2 (Spectrum C) and Cu(10%)Mn(5%) / γ-Al2O3 (Spectrum D)

[0950] The results of Gaussian deconvolution of the spectrum are described below:

[0951] The spectrum of carbon C1s:

[0952] The C1s spectra in both samples show the presence of two contributions related to CC / CH bonds and C=O bonds. These bonds are typical for air pollution.

[0953] The spectrum of oxygen O1s:

[0954] The O1s spectrum of Cu(10%)Mn(5%) / ZrO2 (spectrum C) shows the presence of three contributions related to copper(II) oxide CuO, zirconium oxide ZrO2 and O=C bonds, which have been identified in the carbon spectrum.

[0955] The O1s spectrum of Cu(10%)Mn(5%) / γ-Al2O3 (spectrum D) presents four contributions and highlights the presence of alumina γ-Al2O3, copper(II) oxide CuO, and O=C bonds associated with surface contamination.

[0956] Spectrum of copper Cu2p:

[0957] The spectrum of copper Cu2p is not explained only by deconvolution. The position of different peaks and the overall shape of the spectrum can reflect the degree of oxidation of the element. The overall shape of the Cu2p spectrum of Cu(10%)Mn(5%) / ZrO2 (spectrum C) shows very obvious satellite peaks at about 943eV and 963eV. 2+ ions, particularly in the form of oxidized CuO.

[0958] The deconvolution of the Cu2p3 / 2 peak also showed the presence of small amounts of Cu in metallic and ionic form. + form of copper.

[0959] The overall shape of the Cu2p spectrum (spectrum D) of Cu(10%)Mn(5%) / γ-Al2O3 also corresponds to Cu 2+ ions and a smaller proportion of Cu + ion.

[0960] Spectrum of manganese Mn2p:

[0961] As with copper Cu2p, the shape of the spectrum of manganese Mn2p teaches about its oxidation state.

[0962] Cu(10%)Mn(5%) / ZrO2 (spectrum C)

[0963] The overall shape of the Mn2p spectrum of Cu(10%)Mn(5%) / ZrO2 shows the presence of a satellite peak at about 648 eV, which is 2+ The deconvolution of the Mn2p3 / 2 peak confirmed that the oxidation degree (II) mainly exists on the surface of the sample, and the Mn 3+ ions and Mn 4+ The presence of small amounts of ions.

[0964] Cu(10%)Mn(5%) / γ-Al2O3 (spectrum D)

[0965] The overall shape of the Mn2p spectrum of Cu(10%)Mn(5%) / γ-Al2O3 does not show any 2+ Satellite peaks of ions.

[0966] Deconvolution of the Mn2p3 / 2 peak confirmed that for this sample, the main ions present on the surface are Mn 3+ Ion. Mn 2 + ions and Mn 4+ Ions were identified in smaller proportions.

[0967] Spectrum of zirconium Zr3d:

[0968] The Zr3d spectrum of Cu(10%)Mn(5%) / ZrO2 (spectrum C) consists of spin-orbit pairs, and their contributions are all related to zirconium oxide ZrO2.

[0969] Spectrum of aluminum Al2p:

[0970] The spectrum of aluminum Al2p of Cu(10%)Mn(5%) / γ-Al2O3 (spectrum D) has a single component corresponding to aluminum oxide γ-Al2O3. The shoulder observed at about 77 eV corresponds to the peak of copper 3p.

[0971] Spectra of silicon Si2p and sodium Na1s:

[0972] The silicon Si2p spectrum (C spectrum) of Cu(10%)Mn(5%) / ZrO2 shows the presence of silicon oxide SiO2.

[0973] The sodium Na1s spectrum of Cu(10%)Mn(5%) / ZrO2 (spectrum C) has a unique composition typical of air pollution.

[0974] in conclusion

[0975] Cu(10%)Mn(5%) / ZrO2 (spectrum C)

[0976] XPS analysis of Cu(10%)Mn(5%) / ZrO2 showed that most of the zirconium oxide ZrO2 was present on the surface. Manganese was also identified to be present in a smaller proportion. Manganese appeared in different ionic forms: Mn 2+ 、Mn 3+ and Mn 4+ Most of the Mn 2+ The form of MnO is consistent with the presence of oxides. 3+ The presence of ions is consistent with the compound CuMn2O4 identified by XRD. 2+ The presence of copper is identified by the ionic form, which is consistent with copper(II) oxide CuO and the compound CuMn2O4.

[0977] Cu(10%)Mn(5%) / γ-Al2O3 (spectrum D)

[0978] XPS analysis of Cu(10%)Mn(5%) / γ-Al2O3 showed that most of the aluminum oxide γ-Al2O3 was present on the surface. Manganese was also identified to be present in a smaller proportion. Manganese appeared in different ionic forms: Mn 2+ 、Mn 3+ and Mn 4+ Most of the Mn 3+ The form of CuMn2O4 is consistent with the compound identified by XRD.2+ The presence of copper was identified by the ionic form, which was consistent with the copper(II) oxide CuO and the compounds CuMn2O4 and CuAl2O4 identified by XRD.

[0979] Example 11 - Continuous Flow Hydrogenation Procedure

[0980] The 0.05M to 0.5M oxamide solution in THF is pumped into the reactor at a rate of 0.3mL / min to 3mL / min. Then, the pressure of the system is set between 30bar and 100bar using a back pressure regulator, and the reactor is subsequently heated to between 150°C and 220°C. The reactor is composed of a stainless steel tube, in which the catalyst (between 150mg and 700mg) for the reaction is positioned. Finally, hydrogen is introduced from the outside through a valve or produced in situ in the equipment and injected into the system at a desired flow rate between 20mLN / min and 100mLN / min. Ultimately, the catalyst is first contacted with a hydrogen stream before the reagent is introduced. When the system is stable, the product is collected in a vial at the reactor outlet before being analyzed by GC-MS.

[0981] Example 12 - Procedure for Degradation of Ethylene Glycol by Reduction under Hydrogen in the Presence of CuCo / ZrO2 Catalyst

[0982] A copper (4 mmol Cu) and cobalt-based heterogeneous catalyst, ethylene glycol (10 mmol), a base (potassium tert-butoxide (KOtBu)) and tetrahydrofuran (THF) (75 mL) as solvent were introduced into a 450 mL Parr autoclave equipped with a magnetic stirrer. The reactor was sealed and the reaction mixture was purged three times with nitrogen (5 bar) and twice with hydrogen (5 bar).

[0983] The autoclave is then pressurized with 60 bar of hydrogen.The reaction medium is then stirred at 180° C. to 200° C. for 15 hours.

[0984] When the reaction was complete, the autoclave was returned to room temperature, decompressed, and purged with nitrogen (5 bar) three times.

[0985] The final mixture obtained was diluted and an internal standard (mesitylene) was added to calculate the conversion of ethylene glycol using GC-MS.

[0986] The equilibrium of the degradation reaction of ethylene glycol by hydrogenation in the presence of the CuCo / ZrO2 catalyst is as follows:

[0987]

[0988] Example 13 - Tests with the Cu-Co / ZrO2 catalyst

[0989] Table 21 shows the conditions for the hydrogenation degradation test of ethylene glycol in the presence of the catalyst CoCu / ZrO2 prepared according to Example 5. The ethylene glycol conversion was calculated using GC-MS, with mesitylene used as an internal standard.

[0990] Table 21: Experimental conditions and results obtained for the hydrogenation of ethylene glycol in the presence of the catalyst CoCu / ZrO2.

[0991]

[0992]

[0993] Example 14: Effect of introducing a second metal M into a copper-based supported catalyst on a zirconium dioxide support in a process for preparing ethylene glycol by hydrogenation of oxalamide.

[0994] Table 3 of Example 5 shows that a monometallic catalyst of copper, cobalt, and nickel on a zirconium dioxide support is inactive for the hydrogenation reaction of oxalamide in the process for preparing ethylene glycol. It should be noted that, since iron and manganese are known to be reduced at higher temperatures (above 200° C.) under a reducing atmosphere, the monometallic catalyst of iron and manganese does not have active metal sites for catalyzing the hydrogenation reaction and is therefore a priori an inactive catalyst for the hydrogenation of oxalamide to ethylene glycol.

[0995] Table 22 below shows the results of the selectivity for producing ethylene glycol from oxalamide hydrogenation tests in the presence of a copper-based supported catalyst under similar conditions (temperature, pressure or temp), at a constant copper content, i.e., a copper content of 10% based on the total weight of the catalyst, in the absence of a second metal and in the presence of a second metal M selected from Co, Fe and Mn (in an amount of 5% based on the total weight of the catalyst). Table 22: Conditions and results obtained for oxalamide hydrogenation tests in the presence of a copper-based supported catalyst, in the presence and absence of a second metal M

[0996]

[0997] The following conclusions can be drawn from the tests in Table 3 and Table 22:

[0998] - Monometallic catalysts on zirconium dioxide supports are inactive for the hydrogenation of oxalamide.

[0999] The presence of a second metal element on the surface of the support makes it possible to obtain an active copper-based catalyst.

[1000] - A promoter effect on the catalytic activity of copper-based catalysts in the hydrogenation of oxamide, in terms of substrate conversion (values ​​ranging from 50% to 70%) and selectivity for the reaction to ethylene glycol (values ​​ranging from 67% to 80%), attributed to the presence of a second metal element.

[1001] Example 15: Effect of introducing a second metal M into a copper-based supported catalyst on an alumina support in a process for producing ethylene glycol by hydrogenation of oxalamide.

[1002] Table 23 below shows the results of the selectivity for producing ethylene glycol from oxalamide hydrogenation tests in the presence of a copper-based supported catalyst under similar conditions (temperature, pressure or temp) at a constant copper content, i.e., a copper content of 10% based on the total weight of the catalyst, in the presence of a second metal M selected from Co, Ni and Mn (in an amount of 2% to 5% based on the total weight of the catalyst), the conversion of the substrate (oxalamide), and the yield of ethylene glycol.

[1003] Table 23: Conditions and results obtained for the oxalamide hydrogenation experiments in the presence of a copper-based catalyst and in the presence of a second metal M

[1004]

[1005] The experiments in Table 23 show the following conclusions: the promoter effect on the catalytic activity of the copper-based catalyst for the hydrogenation of oxamide due to the presence of the second metal element is such that:

[1006] - the conversion of the substrate has values ​​ranging from 68% to 100%,

[1007] - the selectivity of the reaction to ethylene glycol is between 68% and 80%,

[1008] - and ethylene glycol production yields of 55% to 80%.

[1009] The selectivity of the bimetallic catalyst on an alumina support for the hydrogenation reaction of oxamide to produce ethylene glycol is significantly better than the selectivity of the hydrogenation reaction prepared by a copper monometallic catalyst on a mixed support of alumina and silica in the prior art.

[1010] Example 16: Analysis of bimetallic catalysts by temperature-programmed reduction in a reducing atmosphere

[1011] Materials and methods

[1012] Temperature programmed reduction (PTR) or (TPR) analysis is used to characterize solid materials, including metal oxides (oxide type, oxide mixture, dispersion on a support). This analytical technique, performed under a reducing atmosphere, is known to the skilled person for characterizing heterogeneous catalysts.

[1013] It consists of determining the amount of hydrogen consumed as a function of temperature. It makes it possible to determine the temperature at which the reduction from the oxidized form to the metallic form occurs and possibly the nature of the metal oxides and the ratios between the metal oxides present.

[1014] The measurements were performed by temperature-programmed reduction in hydrogen (H2-TPR) using a Micromeritics AutochemII 2920 analyzer.

[1015] In a typical experiment, a 50 mg sample was pretreated at 200°C (heating rate = 10°C / min) for 30 min under a helium (He) flow (30 mL / min). The sample was then cooled to 30°C, maintaining the He flow. Reduction analysis was performed from 30°C to 900°C (heating rate = 5°C / min) under a 5 vol% H2 in argon flow (30 mL / min). The final temperature (900°C) was maintained for 30 minutes.

[1016] result

[1017] The analysis of the bimetallic catalyst prepared according to Example 2 by temperature programmed reduction in a dihydrogen reducing atmosphere was Figure 11 It shows:

[1018] -Cu(10%)Co(5%) / γ-Al2O3,

[1019] -Cu(10%)Mn(5%) / γ-Al2O3,

[1020] -Cu(10%)Co(5%) / ZrO2,

[1021] -Cu(10%)Mn(5%) / ZrO2.

[1022] Analysis of the temperature curves indicates that:

[1023] Cu(10%)Co(5%) / γ-Al2O3( Figure 11 a): The reduction peak at low temperature has two maxima at 204°C and 215°C, which may correspond to the continuous reduction of CuO to Cu2O and Cu2O to Cu, respectively. In addition, the reduction peak at high temperature (centered at 285°C) may be related to the reduction of Co3O4 to CoO and the subsequent reduction to Co in close interaction with copper species.

[1024] Cu(10%)Mn(5%) / γ-Al2O3( Figure 11 b): The main reduction peak is located at 233 ° C, which can react with CuO on the surface of alumina. x and Mn x O yspecies (and / or the corresponding mixed oxide Cu x Mn y O z ), which are reduced to similar temperatures to form metallic copper and MnO.

[1025] Cu(10%)Co(5%) / ZrO2( Figure 11 c) The low-temperature reduction peak has two maxima at 155°C and 174°C, which may correspond to the continuous reduction of CuO to Cu2O and Cu2O to Cu, respectively. In addition, the high-temperature reduction peak (centered at 221°C) may be related to the reduction of Co3O4 to CoO and the subsequent reduction to Co.

[1026] The reduction peak of Cu(10%)Mn(5%) / ZrO2- at low temperature has two maxima at 157℃ and 169℃, which can be corresponding to the continuous reduction of CuO to Cu2O and Cu2O to Cu, respectively. The main reduction peak is located at 226℃, which can be related to the Mn on the zirconia surface. x O y species (and / or the corresponding mixed oxide Cu x Mn y O z ) to form metallic copper and MnO.

Claims

1. Use of a supported bimetallic catalyst having the formula Cu-M / support in a method for preparing ethylene glycol from an oxamide or oxamate compound, wherein: M represents Mn, Co, Ni or Fe respectively, and the hydrogenation reaction of the oxamide or oxamate compound is carried out by hydrogen (H2) to obtain ethylene glycol. The catalyst includes copper and metal M on a carrier, and the metal M is selected from manganese, cobalt, nickel and iron.

2. The use according to claim 1, wherein The support is an oxide.

3. The use according to claim 2, wherein The carrier is zirconium dioxide (ZrO2) or aluminum oxide (γ-Al2O3).

4. A method for preparing ethylene glycol, comprising: A hydrogenation step of an oxalate or oxamate compound to ethylene glycol by hydrogen in the presence of a supported bimetallic catalyst having the formula Cu-M / support, wherein M represents Mn, Co, Ni or Fe, the catalyst comprising copper and a metal M on a support, the metal M being selected from manganese, cobalt, nickel and iron.

5. The method for preparing ethylene glycol according to claim 4, wherein: The catalyst carrier is zirconium dioxide (ZrO2).

6. The method for preparing ethylene glycol according to claim 4, wherein: The catalyst carrier is gamma alumina (γ-Al2O3).

7. The method for preparing ethylene glycol according to any one of claims 4 to 6, wherein: The hydrogenation step includes o Contacting the following to obtain a reaction medium that can be pressurized: - the oxamide or oxamate compound, -dihydrogen, - the supported bimetallic catalyst having the formula Cu-M / support, wherein M represents Mn, Co, Ni or Fe, the catalyst comprising copper and metal M on a support, the metal M being selected from manganese, cobalt, nickel and iron, - Optional base - optionally a solvent, o optionally, heating the reaction medium, to obtain ethylene glycol.

8. The method for preparing ethylene glycol according to any one of claims 4 to 7, wherein: The oxamide compound has the following formula 1: Among them, R a and R b Independently of each other: Hydrogen atoms, C1 to C 20 a straight-chain or branched alkyl group, C2 to C 20 a straight-chain or branched alkenyl group, C1 to C 20 a straight-chain or branched heteroalkyl group, C3 to C 20 an aryl or heteroaryl group, C5 to C 20 an alkyl-aryl or alkyl-heteroaryl group, C3 to C 10 cycloalkyl groups, R a or R b At least one of the groups is different from hydrogen, R a and R b Can form a ring.

9. The method for preparing ethylene glycol according to any one of claims 4 to 7, wherein: The oxamate compound has the following formula 2: Among them, R a and R b Independently of each other: Hydrogen atoms, C1 to C 20 a straight-chain or branched alkyl group, C2 to C 20 a straight-chain or branched alkenyl group, C1 to C 20 a straight-chain or branched heteroalkyl group, C3 to C 20 an aryl or heteroaryl group, C5 to C 20 an alkyl-aryl or alkyl-heteroaryl group, C3 to C 10 cycloalkyl groups, R a or R b At least one of the groups is different from hydrogen, R a and R b Can be covalently linked to form a ring, Among them, R c represents a group selected from the following: C1 to C 10 a straight-chain or branched alkyl group, and C3 to C 10 cycloalkyl groups, C3 to C 20 an aryl or heteroaryl group, C5 to C 20 Alkyl-aryl or alkyl-heteroaryl groups.

10. The method for preparing ethylene glycol according to any one of claims 4 to 9, in, Using hydrogen at a pressure of 2 MPa to 10 MPa, in particular 6 MPa, wherein the reaction medium is heated to a temperature of 100° C. to 250° C., in particular 180° C. to 220° C., optionally wherein the reaction medium is heated for 5 hours to 24 hours, in particular 8 hours or 16 hours, wherein, during the step of heating the reaction medium, the supported bimetallic catalyst is activated, the activated catalyst comprising: 80% to 100%, in particular 95% to 100%, preferably 100%, of metallic copper atoms Cu(0) in a zero oxidation state, and - 80% to 100% of metal M in a degree of oxidation greater than zero, preferably said metal M not being in metallic form.

11. A supported bimetallic catalyst having the formula Cu-M / ZrO2, said catalyst comprising copper and a metal M selected from the group consisting of Mn and Co on the surface of a zirconium dioxide support, in, The catalyst has a specific surface area of ​​1 m 2 / g to 50m 2 / g.

12. The catalyst according to claim 11, wherein The zirconium dioxide support is manganese-free and / or chromium-free.

13. The catalyst according to any one of claims 11 to 12, wherein The catalyst has a specific surface area of ​​1 m 2 / g to 10m 2 / g, especially about 5m 2 / g.

14. The catalyst according to any one of claims 11 to 12, in, The zirconium dioxide carrier includes a crystalline phase, and X-ray diffraction analysis shows that the phase is monoclinic.

15. The catalyst according to claim 14, wherein The crystalline phase accounts for 50% to 90% of the total weight of the catalyst.

16. The catalyst according to any one of claims 14-15, wherein The crystalline phase is baddeleyite.

17. The catalyst according to any one of claims 11 to 16, wherein The catalyst includes a crystalline phase, and according to X-ray diffraction analysis, the crystalline phase includes a crystallite size of 15 nm to 100 nm.

18. A supported bimetallic catalyst having the formula Cu-M / γ-Al2O3, said catalyst comprising copper and metal M on the surface of a γ-alumina support, said metal M being selected from the group consisting of Mn and Co, in, The catalyst has a specific surface area of ​​100 m 2 / g to 200m 2 / g.

19. The catalyst according to any one of claims 11 to 18, wherein The catalyst is analyzed by performing temperature programmed reduction (TPR) in a dihydrogen reducing atmosphere at a temperature range of 30° C. to 900° C., wherein the reduction temperature of metallic copper with an oxidation degree (0) is in the range of 150° C. to 250° C., In particular, at a temperature at least 10° C. higher than the reduction temperature of said metallic copper as analyzed by TPR, 80% to 100%, preferably 100%, of the copper atoms are in metallic form, From 80% to 100%, preferably 100%, of the atoms of the metal M are in oxidized form.

20. The catalyst according to any one of claims 11 to 19, in, Under a reducing atmosphere of hydrogen, at a pressure of 2 MPa to 10 MPa and a temperature of 150° C. to 250° C., particularly 180° C. to 220° C., the catalyst comprises: 80% to 100%, in particular 95% to 100%, preferably 100%, of metallic copper atoms Cu(0), and - 80% to 100% of atoms of metal M in a degree of oxidation greater than zero, preferably said metal M not being in metallic form.

21. A method for preparing a Cu-M / support catalyst, the method comprising: Step A, impregnating a copper salt and a salt of a metal M dissolved in an aqueous solution without additives and surfactants onto a support in powder form, wherein the aqueous solution is 5 mL to 10 mL by volume of water, the M being selected from Mn, Co, Ni and Fe, and the ratio of the mass of the solution to the mass of the support being 0.6 to 1.0; to obtain the catalyst Cu-M / support in the form of a homogeneous mixture, step B, drying the homogeneous material at a temperature ranging from 60° C. to 100° C. for a period ranging from 10 hours to 24 hours, so as to obtain the catalyst Cu-M / support in the form of a dry homogeneous mixture, • An activation step C comprising calcining said dried homogeneous mixture at a temperature ranging from 200° C. to 1000° C. for a period ranging from 1 hour to 15 hours under air, so as to obtain said catalyst Cu-M / support.

22. The method for preparing the catalyst Cu-M / ZrO2 according to claim 21, comprising: Step A, impregnating a copper salt and a salt of a metal M dissolved in an aqueous solution without additives and surfactants onto a support in powder form, wherein the aqueous solution is 5 mL to 10 mL by volume of water, the M being selected from Mn, Co, Ni and Fe, and the ratio of the mass of the solution to the mass of the support being 0.6 to 1.0; To obtain the catalyst Cu-M / ZrO2 in the form of a homogeneous mixture, The carrier has a surface area of ​​1 m 2 / g to 250m 2 / g, preferably 1m 2 / g to 50m 2 / g, more preferably 1m 2 / g to 10m 2 / g, especially about 5m 2 / g, and comprising a crystalline phase, which is monoclinic crystallized by X-ray diffraction analysis, step B, drying said homogeneous mixture, preferably at a temperature ranging from 60° C. to 100° C. for a period ranging from 10 hours to 24 hours, so as to obtain the catalyst Cu—M / ZrO 2 in the form of a dry homogeneous mixture, • An activation step C, comprising calcining said dried homogeneous mixture, preferably at a temperature comprised between 200° C. and 1000° C., for a period comprised between 1 hour and 15 hours, in order to obtain said catalyst Cu—M / ZrO 2 .

23. A supported bimetallic catalyst having the formula Cu-M / support, the catalyst comprising copper and metal M on a support, wherein M is selected from the group consisting of Mn, Co, Ni and Fe, and the catalyst can be obtained by the method for preparing the catalyst according to any one of claims 21 or 22.

24. The catalyst according to claim 23, wherein The catalyst is analyzed by performing temperature programmed reduction (TPR) in a dihydrogen reducing atmosphere at a temperature range of 30° C. to 900° C., wherein the reduction temperature of metallic copper with an oxidation degree (0) is in the range of 150° C. to 250° C., In particular, at a temperature at least 10° C. higher than the reduction temperature of said metallic copper as analyzed by TPR, 80% to 100%, preferably 100%, of the copper atoms are in metallic form, From 80% to 100%, preferably 100%, of the atoms of the metal M are in oxidized form.

25. The catalyst according to any one of claims 23 or 24, wherein Under a reducing atmosphere containing hydrogen, at a pressure of 2 MPa to 10 MPa and a temperature of 150° C. to 250° C., particularly 180° C. to 220° C., the catalyst comprises: 80% to 100%, in particular 95% to 100%, preferably 100%, of metallic copper atoms Cu(0), and - 80% to 100% of the metal M atoms in a degree of oxidation greater than zero, preferably, The metal M is not in metallic form.

26. An activated supported bimetallic catalyst having the formula Cu-M / support, said catalyst comprising copper and metal M on the surface of a support, said M being selected from the group consisting of Mn, Co, Ni and Fe, wherein 80% to 100%, in particular 95% to 100%, preferably 100%, of the copper atoms are in the zero oxidation state Cu(0), and 80% to 100%, in particular 95% to 100%, preferably 100%, of the atoms of the metal M are in a degree of oxidation greater than zero.

27. The method for preparing ethylene glycol according to any one of claims 4 to 10, wherein: The catalyst is the catalyst according to any one of claims 11-18 and 23-26.

28. Use of a catalyst having the formula Cu-M / support for the hydrogenolysis of ethylene glycol, wherein: M represents Mn, Co, Ni or Fe respectively, and the catalyst comprises copper and a metal M selected from manganese, cobalt, nickel and iron on a carrier.

29. Use of a catalyst of formula Cu-Co / ZrO2 comprising copper and cobalt on a zirconium dioxide support for the hydrogenolysis of ethylene glycol according to claim 28.

30. Use of a catalyst of formula Cu-M / support for depolymerizing biomass by hydrogenolysis of ethylene glycol groups present in compounds constituting said biomass, wherein M represents Mn, Co, Ni or Fe respectively, and the catalyst comprises copper and a metal M selected from manganese, cobalt, nickel and iron on a carrier.

31. Use of a catalyst of formula Cu-Co / ZrO2 comprising copper and cobalt on a zirconium dioxide support for the depolymerization of biomass by hydrogenolysis of ethylene glycol groups present in the compounds constituting said biomass according to claim 30.

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