Method for producing catalysts for high temperature chemical processes and resulting catalysts

Abstract

A method for producing a catalyst comprising a catalytic species consisting of a transition metal deposited on a support, the method comprising the steps of contacting a support with a solution of a metal carbonyl or other organometallic complex of said transition metal, effecting deposition and surface interaction of said transition metal with the surface of said support, and decomposing said metal carbonyl or organocomplex as a result of at least one heat treatment. The resulting catalyst is advantageously used in synthesis gas production and other high temperature industrial chemical processes.

Description

[Technical field]

[0001] The present invention relates to a method for preparing a catalyst for high temperature chemical processes and the resulting catalyst. [Background technology]

[0002] Most of the methods for preparing industrial catalysts for high temperature chemical processes that occur in a heterogeneous phase, such as those used in the production of synthesis gas, an intermediate in important chemical and refinery processes, use the incipient wet impregnation (IWI) method. These methods include: (A) Physical adsorption of aqueous solutions of inorganic salts onto porous layers of carrier materials in the form of powders, discrete particles of various shapes (pellets) or monolithic structures (e.g. honeycomb, foam, mesh). These carrier materials (hereinafter also simply referred to as "carriers"): i) inorganic oxides containing only one cation (e.g. Al2O3, MgO, ZrO2, Ce2O3) and mixed inorganic oxides containing multiple cations, such as Mg-Al oxide "spinel", perovskites, hydrotalcites, yttrium-stabilized zirconium oxide, etc.; ii) consisting of a metal support on whose surface a porous oxide layer suitable for impregnation has been grown (for example an FeCrAl alloy on whose surface a porous oxide layer has been grown by various methods); (B) A drying step of the surface impregnated with an aqueous solution of inorganic salts (e.g. nitrates, halides of Ni, Co, Fe, transition noble metals such as Rh, Ru, Ir, Pt, Pd) at a temperature usually above 100°C; and (C) A calcination step in which the inorganic salt is decomposed at high temperatures, e.g., 450-800° C., to produce inorganic gas species (e.g., NOx, halogens) and oxidative and / or metallic structures on the surface of the support of the catalyst, which contain catalytically active centers. Includes.

[0003] Moreover, in most cases, a further activation step of the catalyst is required before use. For example, Ni-based catalysts for steam reforming (SR) require a further hydrogenation step to reduce the surface species of NiO to metallic Ni species after insertion in the reactor and before starting the plant. It should be noted that in the described methods, it is not possible to reach specific catalytic centers with defined properties at the molecular level, especially by high-temperature treatment, and furthermore, it is necessary to use a suitable proportion of active metal (for example, SR catalysts contain a proportion of Ni even higher than 15 wt.%). Furthermore, high-temperature thermal treatment requires heating furnaces using electrical energy or, more frequently, the combustion of hydrocarbon compounds. These furnaces, when pyrolyzing inorganic salts, generate, in addition to CO2, toxic inorganic gas species that cannot be released into the atmosphere before appropriate treatment.

[0004] Furthermore, many of the catalysts produced by these processes, including transition metals such as Ni, have limited thermodynamic affinity for carbon formation reactions, which impose, for example, a minimum value for the ratio of moles of steam to moles of carbon atoms (the ratio called Steam / Carbon or S / C) in the reactant mixture in synthesis gas production processes, or a minimum value for the ratio of moles of oxygen to moles of carbon atoms (O2 / C ratio) in autothermal reforming (ATR), noncatalytic partial oxidation (POx), catalytic partial oxidation (CPO) and low contact time catalytic partial oxidation (SCT-CPO), the main characteristics of which are described below.

[0005] [Synthetic gas production] Syngas is produced industrially by the steam reforming (SR), non-catalytic partial oxidation (POx) and autothermal reforming (ATR) technologies. A relatively recent variation of the SR process is the gas-heated reforming (GHR) process, which at least partially replaces the radiative heat required for the endothermic catalytic steam reforming reaction with a convective source consisting only of i) hot gases produced by a total combustion reaction, and / or ii) hot syngas produced by an ATR or POx process. Furthermore, when the SR and GHR technologies are integrated with the ATR or POx technologies, they are called combined reforming (CR) processes. The characteristics of the briefly mentioned technologies are described in many publications, among which the following are mentioned: - “Technologies for large-scale gas conversion” Aasberg-Petersen, K., Bak Hansen, J. -H., Christensen, TS, Dybkjaer, I., Christensen, P. Seier, Stub Nielsen, C., Winter Madsen, SEL, Rostrup-Nielsen, JR, Applied Catalysis A: General, 221 (1-2), p. 379, Nov 2001; - “Synthesis Gas production by Steam Reforming”, Dybkjaer, Ib; Seier Christtensen P.; Lucassen Hansen V.; Rostrup-Nielsen JR, EP1097105A1; ‐ “Catalytic Steam Reforming”; Rostrup-Nielsen JR; pp- 1-117, Catalysis Vol. 5, Edited by John R. Anderson and Michel Boudart The low contact time catalytic partial oxidation (SCT-CPO) technology has not yet been applied industrially, but is described in many patent documents, among which the following may be cited: (A1), WO 2016016257 (A1), WO2016016256 (A1), WO2016016253 (A1), WO2016016251 (A1), WO 2011151082, WO 2009065559, WO 2011072877, US 2009127512, WO 2007045457, WO 2006034868, US 2005211604, WO 2005023710, WO 9737929, EP 0725038, EP 0640559. The following references are also cited: - “Issues in H2and synthesis gas technologies for refinery, GTL and small and distributed industrial needs”; Basini, Luca, Catalysis Today, 106 (1-4), p. 34, Oct 2005, - “Fuel rich catalytic combustion: Principles and technological developments in short contact time (SCT) catalytic processes”; Basini, L.; Catalysis Today, 117 (4), 384-393; DOI: 10.1016 / j.cattod.2006.06.043 Published: 15 October 2006, - “Natural Gas Catalytic Partial Oxidation: A Way to Syngas and Bulk Chemicals Production | IntechOpen”; G. Iaquaniello, E. Antonetti, B. Cucchiella, E. Palo, A. Salladini, A. Guarinoni, A. Lainati and L. Basini; http: / / dx.doi.org / 10.5772 / 48708 - “Short Contact Time Catalytic Partial Oxidation (SCT-CPO) for Synthesis Gas Processes and Olefins Production”; LE Basini, A. Guarinoni, Ind. Eng. Chem. Res. 2013, 52, 17023-17037; https: / / doi.org / 10.1021 / ie402463m.

[0006] Syngas is used in many chemical processes, such as the synthesis of methanol and its derivatives, ammonia and urea synthesis, Fischer-Tropsch synthesis of liquid hydrocarbons, hydrogen production, and has many applications in refining processes, petrochemical processes, fine chemical processes, electronics industry, metal refining and food industry. The aforementioned industrial processes require syngas of various compositions to improve energy efficiency and reduce greenhouse gas (GHG) emissions.

[0007] Furthermore, the use of synthesis gas in reduction processes for iron-based minerals is also increasing, but so far only to a small extent in direct reduction (DR) processes, where synthesis gas is currently produced by the SR process (Steam-CO2 Reforming - SCR process) with the addition of an appropriate amount of CO2 to the steam in the reagent mixture.

[0008] [Catalysts for catalytic partial oxidation reactions] The most active transition metal species for catalytic partial oxidation (CPO) reactions, especially for low contact time catalytic partial oxidation (SCT-CPO) reactions, as described in the literature, include Rh, Ir, Ru and Ni, which are bonded to each other. Rh is the preferred choice among the noble metals due to its chemical reactivity characteristics and the fact that it has the highest tem- perature among the aforementioned metals. The latter is half the temperature of the metal melting point and is considered to be the temperature at which the surface aggregation process (sintering) of atomic species begins, leading to the formation of large metal aggregates, which have the detrimental effect of reducing the dispersion of active catalytic centers and of the intrinsic reactivity of the catalyst. These points are also described in:- R. Merkle und J. Maier Stuttgart (Max Planck Institut fur Festkorperforschung), Z. Anorg. Allg. Chem. 2005, 631, 11631166 (DOI:10.1002 / zaac.200400540); - “Fuel rich catalytic combustion: Principles and technological developments in short contact time (SCT) catalytic processes”; L. Basini; Catalysis Today 117 (2006) 384-393; - “Two-dimensional modeling of partial oxidation of methane on Rhodium alumina support in a short contact time reactor”; O. Deutschman, LD Schmidt, AIChE Journal;44 (1998) pp. 2465-2477

[0009] It is worth noting that while Rh and Ir species have particular application in the early part of the catalyst bed where the CPO or SCT-CPO reactions take place, the use of catalysts containing Ru and Ni, which can form volatile and toxic oxidizing species, can affect the oxygen partial pressure (P O2) and is preferably used in the subsequent zones of the catalyst bed where reducing molecules, i.e. CO and H2, are the main components. More specifically, Ni-containing catalysts, as described, for example, in US2017173568 A1(B2), are used in the end parts of the catalyst bed to not only complete the SCR reaction but also to convert unsaturated hydrocarbon compounds formed in the early part of the catalyst bed into CO and H2. O2 It has been reported that this is particularly useful when the ratio of the synthesis gas to the total synthesis gas is close to zero. Indeed, the formation of unsaturated compounds in the synthesis gas mixture must be avoided to prevent their accumulation on the reactor and heat exchanger surfaces where steam is generated. Also, since said unsaturated compounds are generated, for example, in the aforementioned processes for the production of ammonia and urea, in the production of methanol and its derivatives, in the production of hydrogen and in the Fischer-Tropsch process, a reactor must be installed downstream to cool the synthesis gas before it can be used. Summary of the Invention [Problem to be solved by the invention]

[0010] The catalytically active metals in the above mentioned CPO and / or SCT-CPO processes can be deposited in various ways on the surface of oxidizing supports such as aluminum, magnesium, cerium, zirconium, lanthanum oxides and other oxides or mixed oxides containing other different cationic species and having different structures, but also on metallic supports, which can be in the form of pellets of various shapes or monoliths such as honeycomb structures, foam structures and in the case of metallic supports, various types of mesh and gauze structures.

[0011] As already mentioned, the industrial method for depositing catalytically active metals on catalyst supports uses the incipient wetness impregnation (IWI) method with aqueous solutions of inorganic salts (see, for example, US 5,336,655), and as mentioned above, the known process has obvious drawbacks, such as the need to carry out a thermal or high-temperature "calcination" treatment, which reduces the dispersion of the catalytically active metals and therefore requires the use of large amounts of the catalytically active metals, and which, upon decomposition of the inorganic salts, leads to the emission of harmful substances which cannot be released directly into the atmosphere and which must be removed from the exhaust gases.

[0012] Moreover, high-temperature heat treatment requires a furnace, which consumes considerable energy. Furthermore, the obtained catalyst may require an activation treatment. For example, catalysts with a high Ni content (usually 15 wt.% or more), such as those used in the SR process, require an activation treatment to convert oxidized species to metallic Ni species before use. The low dispersion and large amount of catalytically active metals also increase the thermodynamic affinity for the carbonaceous species production reaction, imposing limitations on the S / C and O2 / C ratios in the reagent mixture. This is not necessarily suitable for generating optimal syngas compositions for downstream processes that utilize syngas, which reduces the overall energy efficiency of the catalytic process.

[0013] Therefore, there is a need for new methods for producing catalysts for industrial chemical processes which eliminate or reduce the disadvantages of known methods. [Means for solving the problem]

[0014] Thus, one aspect of the present invention is a method for the preparation of a catalyst for a chemical process comprising catalytic species consisting of one or preferably more than one transition metal or compound of said transition metals deposited on a support, the method comprising: a) preparing a solution in an organic solvent of an organometallic compound of the transition metal which produces the catalytic species and contacting said solution with said support, wherein said organometallic compound is selected from metal carbonyls and complexes of the transition metal with organic ligands, and said support is selected from the group consisting of inorganic oxides, nitrides, oxynitrides, carbides, borides, and metal compounds having oxide structures formed on their surfaces; b) depositing said solution of an organometallic compound of said transition metal on the surface of said support by a chemisorption or physisorption process; c) removing the organic solvent of the solution of the transition metal deposited on the surface of the support and completely or partially decomposing the organometallic compound of the transition metal remaining on the surface of the support by at least one heat treatment, thereby precipitating one or more catalytic species of the transition metal on the support; The present invention relates to a method for producing the same,

[0015] Another aspect of the present invention relates to a catalyst obtainable by the above process.

[0016] A further aspect of the present invention is the use of said catalyst in CO2 reforming (CR), steam reforming (SR), steam-CO2 reforming (SCR), catalytic partial oxidation (CPO) and low contact time catalytic partial oxidation (SCT-CPO) processes for synthesis gas production. [Brief description of the drawings]

[0017] The present invention will now be described with reference to the accompanying drawings, in which: [Figure 1] FIG. 1 is a diagram of a method for producing a catalyst according to the prior art. [Diagram 2] FIG. 1 is an illustration of an embodiment of a method for producing a catalyst according to the present invention. [Diagram 3] FIG. 1 is an illustration of an embodiment of a method for producing a catalyst according to the present invention. [Figure 4] FIG. 1 is an illustration of an embodiment of a method for producing a catalyst according to the present invention. [Diagram 5] FIG. 1 is an illustration of an embodiment of a method for producing a catalyst according to the present invention. [Figure 6] FIG. 1 is an illustration of an embodiment of a method for producing a catalyst according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] According to one aspect of the invention, the reactions for producing industrial catalysts and for producing synthesis gas are advantageously carried out using organic solutions of organometallic complexes of transition metals, said organometallic complexes consisting of metal carbonyls and / or complexes of transition metals with organic ligands. Hereinafter, the terms "organometallic compound" or "organometallic complex" of transition metals are used interchangeably.

[0019] In addition to the physical interaction with the catalyst support surface, the carbonyl compounds can also undergo chemical interaction, allowing the selective grafting of catalytically active metals to the chemically active sites of the support species, such as the coordinatively unsaturated (cus) sites, Bronsted acid sites and / or Lewis acid sites. With reference to step b) of the method defined above, the term "chemisorption" denotes adsorption accompanied by chemical transformation of the adsorbed organometallic compound, and the term "physisorption" denotes adsorption without chemical transformation and without decomposition of the adsorbed compound.

[0020] According to one aspect of the invention, the carbonyl compound may be selected such that only CO2 and H2O are desorbed during its decomposition. Furthermore, the interactions between these organometallic compounds and the supports can be tailored to produce monolayers or submonolayers of catalytically active metal surface species following vacuum removal of the organic solvent at room temperature and moderate drying steps at temperatures up to 100° C.

[0021] When the organometallic compound is appropriately selected, the reaction between the organic solution and the surface of the catalyst support can be directed to the formation of monometallic species or surface clusters having two or more metal atoms with unique and unpredictable reaction properties based on the known characteristics of the metal compounds obtained on the surface of the same catalyst support by an incipient wetness process using the organometallic compound in solution or an aqueous solution of an inorganic salt of the same transition metal.

[0022] Carbonyl compounds can be obtained by simple carbonylation of inorganic precursors, e.g. Rh4(CO) 12 , Rh6(CO) 16 , Ru3(CO), Ir4(CO) 12 , Fe2(CO)9, Fe3(CO) 12 , Co2(CO)8, Co4(CO) 12 , Co6(CO) 16 You can choose from.

[0023] Alternatively, a transition metal and acetylacetonate (Acac=CH3COCHCOCH3 - ) can also be used, where the transition metal is, for example, Ni, Fe, Co, or a noble transition metal such as Rh, Ru, Ir, Pt, Pd.

[0024] The method of the invention not only improves known methods for the preparation of catalysts, but also improves the performance of the catalysts obtained, in particular for use in the processes: i) CO2 reforming (CR), ii) steam-CO2 reforming (SCR), iii) catalytic partial oxidation (CPO) or low contact time catalytic partial oxidation (SCT-CPO), in which synthesis gas can be produced that can be used in processes for the production of ammonia / urea, methanol and its derivatives, hydrogen, and in other processes with limited use of the synthesis gas produced by these methods, such as processes for the reduction of iron-based minerals.

[0025] According to the invention, in the preparation of the catalyst, organometallic compounds, in particular compounds containing only CO ligands, such as Rh4(CO) 12, Rh6(CO) 16 , Ru3(CO) 12 , Ir4(CO) 12 , Fe2(CO)9, Fe3(CO) 12 , Co2(CO)8, Co4(CO) 12 , Co6(CO) 16 Using this has the following advantages: i) the deposition of catalytic metals by selective interaction between organometallic clusters and reactive sites on the surface of the catalyst support, resulting in materials with highly dispersed catalytic sites which make it possible to reduce the amount of transition metal while maintaining values ​​of catalytic activity, and therefore of the combined conversion of reactants and selectivity towards CO and H2, comparable or superior to those obtained by the incipient wetness process using aqueous solutions of inorganic salts of the same transition metals; ii) the final catalyst for use in the reactor can be obtained using thermal treatment, thus avoiding the high temperature calcination steps required for decomposing the adsorbed inorganic salts using aqueous solutions by the incipient wetness method, thus avoiding the emission of NOx and other polluting inorganic gaseous compounds; iii) Reduces metal waste when producing large quantities of industrial catalysts compared to spraying an aqueous solution of inorganic salts onto the catalyst support until the support reaches its incipient wetness value, and then evaporating the aqueous solution to dryness; iv) Both in the case where a support in the form of pellets or in the case where a support of monolithic structure is used, monolithic catalysts can be produced with a high dispersion of the active metals and therefore of the catalytic centres, which are particularly useful for use in CPO and / or SCT-CPO reactors, where a reduction of the pressure drop in the reactor is important, thus allowing the implementation of more favourable low pressure operating conditions, for example in processes for the reduction of iron-based minerals.

[0026] By using an organic solution of carbonyl clusters, i) Deposition of active metals by incipient wetness impregnation (IWI) method using organic solutions; and ii) Deposition of active metals by solid-liquid reactions obtained by dispersing a solid support in an organic solution containing carbonyl clusters. It should be emphasized that both are possible.

[0027] In this regard, Rh dispersed in n-hexane or THF solvents 12 (CO) 12 , Ir4(CO) 12 , Ru3(CO) 12 Extensive studies on the formation and reactivity characteristics of surface metal species generated by solid-liquid reactions of clusters with active surface sites of MgO, a-Al2O3, CeO2, La2O3, ZrO2 and TiO2 have been published in the scientific literature. In this regard, please see: - “Drift and Mass Spectroscopic Studies on the Reactivity of Rhodium Clusters at the Surface of Polycrystalline Oxides” L. Basini, M. Marchionna and A. Aragno; J. Phys. Chem., Vol. 96, No. 23, 1992 - “Molecular and Temperature Aspects in Catalytic Partial Oxidation of Methane”; L. Basini, A. Guarinoni, A. Aragno; J.Catalysis, 190 (2000) pp. 284-295 - “Catalytic partial oxidation of natural gas at elevated pressure and low residence time”; L. Basini, K. Aasberg-Petersen, A. Guarinoni, M. Ostberg; Catalysis Today 64 (2001) 9-20 “In Situ EXAFS Study of Rh / Al2O3 Catalysts for Catalytic Partial Oxidation of Methane”; JD Grunwaldt, L. Basini, BS Clausen*; J. Catal. 200 (2001) pp. 321-329 “DRIFT and Mass Spectrometric Experiments on the Chemistry and Catalytic Properties of Small Ir Clusters at the Surfaces of Poly-crystalline a-Al2O3”, L. Basini and A. Aragno, JCS Faraday Trans. 1994, 90(5), 787-795; - “Molecular Aspects in Syngas Production: the CO2 Reforming Case”; L.Basini, D. Sanfilippo, J.Catal 157(1995) pp. 162-178

[0028] [Iron ore reduction process and use of synthetic gas] The reduction process of iron minerals for steel production mainly uses blast furnaces (BF), with direct reduction (DR) and smelting reduction processes being used less frequently. More specifically, the steel production process using blast furnaces (BFs) has sustainability issues related to the production and use of coke, and the polluting emissions associated with the manufacture of iron minerals that require crushing, sintering and pelletizing. Overall, pollutant emissions include monocyclic and polycyclic aromatic hydrocarbons, sulfur compounds, particulate matter and inorganic acids, with blast furnaces also producing significant amounts of CO2 and NOx. Blast furnaces produce molten metal (cast iron) with a high carbon content (usually around 4% by weight), which is converted to steel in the Basic Oxygen Furnace (BOF). The use of coke oven (COG) and blast furnace (BFG) gases, as well as synthesis gas produced outside the blast furnace, reduces the emissions of the above pollutants and the generation of greenhouse gases, in particular by reducing the production and use of coke and by reusing a share of the COG and BFG that would have been burned to produce thermal and electrical energy.

[0029] On the other hand, in the direct reduction (DR) process of iron ores, no coke is used. The reducing gas is usually produced from natural gas (GN) and can be fed directly to the DR reactor or can be first converted to syngas in a steam-CO2 reforming unit. Direct reduced iron (DRI) produces an iron sponge (cold direct reduced iron (CDRI), hot molded reduced iron (HBI), hot direct reduced iron (HDRI)), which is usually melted in an electric arch furnace (EAF) and converted to steel. On the other hand, the smelting reduction process uses neither coke nor NG, but coal combusted with pure oxygen to generate syngas in the reactor. This solution, like DR, has a lower environmental impact than processes using BF, and its use is expanding. The technology of using syngas in the reduction process of iron ores therefore constitutes an advantageous solution to reduce the environmental impact of these industrial activities and is considered to be of increasing importance in the future. However, in such cases, a mixture with a high CO content is often necessary for the production of syngas to be advantageous. This gas mixture can be obtained by feeding a mixture with a low S / C ratio and a high CO2 / C ratio to the reactor under conditions where known catalysts have a high thermodynamic affinity for the reaction for the production of carbonized residues, which is reduced by the use of the catalyst according to the invention, as described below.

[0030] [Production of metal carbonyl clusters] The preparation of carbonyl derivatives is usually carried out by reduction of the corresponding inorganic compounds. The choice of reducing agent is the most important aspect of this preparation, but if CO is used, an additional reducing agent may not be necessary. If the starting material is a metal oxide or metal chloride, the oxidation product is CO2 (DG°f = -394 kJ mol - 1) or COCl2(DG° f = -206 kJ mol -1 Molecular hydrogen can also be used as a reducing agent in the presence of CO.

[0031] In the dry method, no solvent is used. In the wet method, anhydrous organic solvents are used, usually hydrocarbons or ethers. Exceptionally, in the case of carbonyl derivatives of Pt(II), Pd(II) and Au(I), thionyl chloride (SOCl2) can be used as the solvent, since it provides strictly anhydrous conditions for the survival of the reaction products. In some cases, water can also be used as the reaction medium, with or without the addition of a specific reducing agent. In the latter case, CO is the reducing agent and carbonates are the corresponding oxidation products.

[0032] The preparation methods reported in the literature usually require high temperatures (50-200 °C) and high pressures (50-200 atm), but most of the modern preparation methods operate at room temperature or slightly above and at atmospheric pressure. especially, i) Rh4(CO) 12 can be produced from RhCl3 and CO in a very wide pressure range (PCO = 1-20 MPa), often in the presence of halogen acceptors such as copper, silver, cadmium or zinc. The nature of the product depends on the temperature. At 50-80 °C, tetranuclear compounds are mainly formed, and at 80-230 °C, Rh6(CO) 16is the preferred product. A detailed method for obtaining the clusters in 80-90% yield at atmospheric pressure using RhCl3.3H2O salt is described in “Tri-m-Carbonyl-Nonacarbonyl-Tetra-Rhodium; Rh4(CO)9(pCO)3”; S. Martinengo et al.; Inorganic Syntheses, Volume 28, 1990, pages 243-245. ii) Ir4(CO) 12 can be produced by carbonylation of iridium halides in the presence of a halogen acceptor (copper or silver), usually at high temperature and pressure. CO There are also manufacturing methods that require, for example, 0.1 MPa. 12 "; S. Martinengo et al.; Inorganic Syntheses, Volume 28, 1990, pages 245-248. In the first step, IrCl3.3H2O is converted to [Ir(CO)2Cl2] by high temperature carbonylation. - In the second step, it is converted to [Ir(CO)2Cl2]- - At room temperature, Ir(CO) is formed by partial buffering of the acid. 12 is converted to iii) Ru(CO) at atmospheric CO pressure using hydrated ruthenium(III) chloride RuCl3·xH2O in 2-ethoxyethanol or isopropanol 12 The production of “Dodeca-carbonyl-tri-Ruthenium: Ru3(CO) 12 The "one-pot" method described in "di M. Faure et al., in "Transition Metal CarbonylCompounds;2004"; pp.110-115;https: / / doi.org / 10.1002 / 0471653683.ch3" involves the conversion of a moderate amount of RuCl3.3H2O to Ru3(CO) under 1 atm CO pressure. 12to 1,000,000,000, with yields of over 90%. In fact, it combines the advantages of simplicity, speed, high efficiency, and insensitivity to humidity, allowing the use of all commercially available reagents. iv) Co2(CO)8 can be produced by carbonylation of cobalt(II) salts of organic or inorganic acids in hydrocarbon solvents at moderate temperatures and high pressures (10-18 MPa) with synthesis gas. However, milder conditions are required to produce [Co(CO)4] - There is a synthetic route to form [Co(CO)4] by controlled oxidation. - Co2(CO)8 can be obtained from Co(CO)8. This monometallic anion is produced by carbonylation of aqueous alkaline solutions of cobalt(II) salts at atmospheric pressure and room temperature, using carbon monoxide as the reducing agent. Finely divided cobalt, as obtained from Li / naphthalene and any cobalt halide in diethyl ether of ethylene glycol (1,2-diethoxyethane), is converted in good yields to Co2(CO)8 at 100 °C and 95 atm pressure. Co4(CO) 12 is the product of the thermal decarboxylation of Co2(CO)8.

[0033] [Acetylacetonate formation] Metal acetylacetonates are formed by the acetylacetonate anion (CH3COCHCOCH3 - ) and a metal ion, usually a transition metal. Bidentate acetylacetonate ligands are often abbreviated as "acac". Usually, both oxygen atoms are bound to the metal to form a six-membered chelate ring. In some cases, however, acac also bonds to the metal through the central carbon atom. Therefore, this binding mode is more common with tertiary transition metals such as platinum(II) and iridium(III). The simplest complexes are of the formula M(acac)3 and M(acac)2. Many variations of acetylacetonate are available with various substituents R and R' instead of methyl (general formula R'COCH2COR -have also been developed, where R and R′ can be the same or different and each contain up to six carbon atoms. Many of these complexes, unlike the related metal halides, are soluble in organic solvents. The following are some of the known acac compounds: Fe(acac)3, Co(acac)3, Ni(acac)2and [Ni(acac)2]3, e Rh(acac)3, Ru(acac)3, Ir(acac)3, e Ir(acac)(CO)2, Pt(acac)2, Pd(acac)2. A common synthetic method is treatment of a metal salt with acetylacetone (acacH). M z+ + z Hacac ⇔ M(acac) z +zH + However, in some cases, transition metal carbonates can be used, as in the following reaction: 2 CoCO3+ 6 Hacac + H2O2→ 2 Co(acac)3+ 4 H2O + 2 CO2

[0034] [Rh4(CO) 12 , Ir4(CO) 12 , Ru3(CO) 12 and solid-liquid reaction of organic solutions of Ni, Co, Fe, Rh, Ir, Ru, Pd, and Pt Acac complexes with catalyst supports] Carbonyl cluster Rh4(CO) 12 , Ir4(CO) 12 , Ru3(CO) 12 n-Hexane and THF solutions of 10 m 2 The solid-liquid reactivity of MgO (CO) with the polycrystalline MgO surface, α-Al2O3, CeO2, La2O3, ZrO2 and TiO2 has been extensively described above. In short, if we limit the discussion to the α-Al2O3 support, this method can be used with M-0-Rh'(CO)2, M-HIr4(CO) 11In this regard, see: “Reactivity of Ruthenium Carbonyls on Metal Oxide Surfaces: Effects of the Surface Acid-Base Chemistry”; S. Uchiyama, BC Gates; Inorganica Chimica Acta, 147 (1988) 65-70; and “Surface characterization of the Ru3(CO) 12 -Al2O3system: I. Interaction with the hydroxylated surface”; A. Zecchina et Al., J. Catal., 74 (1982), pp. 225-239; 1707439768459_0 . It should also be noted that the dissociation reactions of clusters on monometallic species are more effective on CeO2 and TiO2 surfaces and less effective on MgO and La2O3. In any case, drying and / or thermal treatment under moderate vacuum conditions decomposes the surface carbonyl species, leaving bare metal atoms on the catalyst support. However, it is also noted that the carbonyl species obtained after drying are already active in SR, SCR, CPO and SCT-CPO reactions and are converted to the final species of bare metal clusters on the catalyst surface during the initial reactions. Virtually all acac complexes soluble in organic solvents (e.g., MeOH, THF, CHCl3) can react with the coordinatively unsaturated surface sites (cus) of the support via liquid-solid interactions. With respect to surface OH groups, there seems to be a correlation between the acid / base sensitivity of the acac complexes and their reactivity towards these groups. - In the presence of +Those sensitive to acetylacetonates react (to some extent) with acidic OH. See “Interaction of Transition-metal Acetylacetonates with y-Al,O, Surfaces”; J. A. Rob van Veen, Gert Jonkers and Wim H. Hesselink, J. Chem. SOC., Faraday Trans. I, 1989, 85(2), 389413. Some of these reactions can be expressed in the following equations for the Al2O3 support: Surface n -OH + M(acac) n -> Surface-O n M + n acacH Surface - Al s 3+ + M(acac) n -> [Al(acac) n ] s (3-n) + M s n+ (where M = Rh, Ru, Ir, Pd, Pt, Ni, Fe, Co, …)

[0035] [Rh4(CO) 12 , Ir4(CO) 12 , Ru3(CO) 12 Incipient wetness impregnation (IWI) of organic solutions and catalyst supports with Ni, Co, Fe, Rh, Ru, Ir, Pt, and Pd Acac complexes] In this case, concentrated organic solutions of carbonyl clusters (e.g., n-hexane or THF) or other solutions of acac complexes (MeOH, THF, CHCl3) are sprayed with a nebulizer or left dripping onto the catalyst support, which is then dried under vacuum at moderate temperatures, usually 25-100 °C. This method is similar to the IWI method used with aqueous solutions of inorganic salts (e.g., Rh(NO)3, Ir(NO)3, Ru(NO)3), but after impregnation, drying and heat treatment are carried out at much lower temperatures or simply under vacuum, since the catalyst does not contain inorganic anionic substances that need to be pyrolyzed at high temperatures to obtain catalytic performance. It should be noted that the IWI method can give rise to both chemisorption phenomena (organometallic compounds decompose and chemically react with the active sites of the support) and physisorption phenomena (organometallic compounds are adsorbed on the support but do not undergo chemical changes).

[0036] [Explanation of the innovative production method of catalysts and the new products obtained by them] The new catalyst manufacturing process and new catalyst products have three manufacturing methods, namely: (A) IWI process using aqueous solutions of inorganic salts; (B) an IWI process using an organic solution of an organometallic compound; and (C) This can be obtained by appropriately combining a solid-liquid reaction between an organic solution of an organometallic complex and a catalyst support dispersed in the same solvent. A block diagram illustrating these methods is shown diagrammatically in FIG.

[0037] Method (A) requires the highest calcination temperatures and leads to emissions of polluting inorganic gaseous compounds (eg, NOx and halogens) that cannot be freely released into the atmosphere. Method (B) does not require a calcination step, but includes a step of preparing an organometallic compound, which then allows for chemical and / or physical interaction between the solid support and the organometallic compound, to obtain a catalyst which may also contain a large amount of catalytically active metal. Method (C), like procedure (B), does not require a calcination step and includes a step of preparing an organometallic compound, but it is possible to selectively deposit a catalytically active metal by a solid-liquid reaction, and also to obtain a monolayer or less than a monolayer deposit of a catalytically active species on a catalyst support. Methods (B) and (C) not only avoid NOx and halide emissions and do not require a calcination step, but are also very effective in obtaining specific compositional features on the catalyst surface, especially when the amount of active metal is low (i.e., sub-monolayer) and high dispersion of catalytic sites is beneficial. Additionally, methods (B) and (C) provide a simpler and more effective way to prepare bimetallic and trimetallic catalysts.

[0038] 2, 3 and 4 include combinations of methods (A) + (B) = (D) or (A) + (C) = (E) and (B) + (C) = (F), which are particularly useful for combining the deposition of relatively large amounts of transition metals, such as Ni, Fe, Co, by method (A), with relatively small amounts of precious metals, such as Rh, Ru, Ir, by methods (B) or (C). The combination of methods (B) and (C) has the same potential as the combination of processes (A) and (B) or (A) and (C), but avoids the need for high temperature processing and the formation of NOx emissions or halide compounds and large surface metal aggregates containing the same concentrations of active metals. Other combination methodologies, (B) + (A) = (G) and (C) + (A) = (H), are included in Figures 5 and 6 and are useful for depositing transition metals such as Ni, Fe, Co by method (A) and precious metals such as Rh, Ru, Ir by methods (B) or (C) in similar amounts, and potentially producing metal alloys on the surface of the catalyst.

[0039] These manufacturing methods can be used for powdered catalyst supports in the form of pellets, or for structured supports in monolithic or other forms. The latter are particularly useful for reducing the pressure drop across the catalyst bed, as already mentioned. In fact, it has been found that the pressure drop using structured catalysts is two orders of magnitude lower than when using packed beds. Furthermore, monolithic supports can also reduce radial and axial temperature gradients due to their greater effective thermal conductivity and regularity of the internal pathways, allowing operation in the layered regime.

[0040] Cordierite is a mixture of oxides of Mg, Si and Al, which is commonly used as a high-temperature structured support formed as a monolith for automotive exhaust gas treatment, see “Nano-Array Integrated Structured Catalysts: A New Paradigm upon Conventional Wash-Coated Monolithic Catalysts?”; Weng, J.; Lu, X.; Gao, P.-X. Catalysts 7(2017) pp. 253-280. Other monolithic ceramic materials have foam structures composed of different oxides, such as Al2O3 and ZrO2, nitriles, such as Si3N4, borides, such as BN, and carbides, such as SiC. Furthermore, monolithic metal supports, such as FeCrAl alloys, are also used when it is advantageous to increase the conductive heat transfer capacity within the catalyst layer, see in this regard “FeCrAl as a Catalyst Support”; Gianluca Pauletto, Angelo Vaccari, Gianpiero Groppi, Lauriane Bricaud, Patricia Benito, Daria C. Boffito, Johannes A. Lercher, and Gregory S. Patience; Chemical Reviews, 2020; https: / / dx.doi.org / 10.1021 / acs.chemrev.0c00149.

[0041] These structured catalysts are used in many reactions. The first applications were in exhaust gas treatment, electrocatalytic reduction (SCR) of NOx, destruction of volatile organic compounds (VOC) and catalytic combustion. Other reactions are currently being developed, such as SR and SCR of natural gas or methanol with steam and CO2 (SCR), catalytic partial oxidation of natural gas (CPO), water-gas shift (WGS) process, Fischer-Tropsch synthesis (FT) and oxidative coupling of methane (OCM).

[0042] State-of-the-art methods for producing catalysts on FeCrAl alloy supports are often laborious and time-consuming, including, for example, a series of steps including the growth of an Al2O3 layer on the outer surface of the FeCrAl alloy, the production of g-alumina powder, possibly modified with stabilizers, impregnation with an aqueous solution containing salts of the precious metals, calcination in air, reduction with hydrogen, preparation of a suspension of the precious metal-alumina powder, repeated immersion of the FeCrAl alloy support in the suspension and drying, and final calcination; see in this regard “Premixed metal fibre burners based on a Pd catalyst”; I. Cerri, M. Pavese, G. Saracco, V. Specchia; Catal. Today 83 (2003); 19 -31.

[0043] Another method involves the preparation of hydrotalcite compounds containing precious metals, followed by calcination and spontaneous deposition by galvanic displacement reactions or electrodeposition reactions, see in this regard “Preparation of 3D electrocatalysts and catalysts for gas-phase reactions, through electrodeposition or galvanic displacement”; M. Musiani, S. Cattarin, S. Cimino, N. Comisso, L. Mattarozzi, L. Va´zquez-Go´mez, E. Verlato; J. Appl. Electrochem.; 45(2015) pp. 715-725.DOI 10.1007 / s10800-015-0808-1.

[0044] The use of organic solutions of organometallic compounds such as carbonyl clusters and / or acetylacetonates in the process of the invention is particularly applicable to the deposition of precious metal species both on ceramic supports (e.g. cordierite) and on metallic supports (e.g. FeCrAl alloys) using the IWI method and the above mentioned solid-liquid reaction methods. By using these methods, the complexity of drying, calcination and reduction steps can be reduced or even completely avoided. Also, the quality of the catalytic properties can be improved with respect to the distribution and grafting of the precious metals, leading to improved performance and lifetime.

[0045] Similarly, the methodology described can be applied to wall reactors that include walls coated with catalytic species. In some cases, these reactors are designed to carry out exothermic reactions, such as combustion, on one side of the wall and endothermic reactions on the other side, see in this regard “Thermal and hydrothermal stability of a metal monolithic anodic alumina support for steam reforming of methane”; Yu Guo, Lu Zhou, Hideo Kameyama; Chem.Eng. J. 168 (2011) 341-350; doi:10.1016 / j.cej.2011.01.036.

[0046] In this case, the heat released by the exothermic reaction is directly transferred to the other side of the wall, driving the endothermic reaction. This configuration significantly reduces the boundary layer heat transfer resistance, thus increasing the speed and efficiency of heat transfer to the environment where the catalytic reaction takes place. Recently, electrified reactors of this type have also been proposed for the steam reforming of methane (SR), see in this regard “Electrified methane reforming: A compact approach to greener industrial hydrogen production”; Wismann et al., Science 364 (2019) 756-759; e “Thermal and hydrothermal stability of a metal monolithic anodic alumina support for steam reforming of methane”; Yu Guo, Lu Zhou, Hideo Kameyama; Chemical Engineering Journal 168 (2011) 341-350; doi:10.1016 / j.cej.2011.01.03.

[0047] The preparation methods using organometallic compounds are also particularly suitable for these applications. In general, it has been reported that the described method makes it possible to produce catalysts with highly dispersed metal species (dispersity 100%) and is therefore particularly advantageous when it is desired to use catalytic systems with low contents of active metals, in particular precious metals. Moreover, these catalysts showed higher activity for SR, CR, SCR in the presence of large amounts of CO2 and catalytic partial oxidation (CPO) at low contact times (SCT-CPO). In these cases, the catalysts prepared with organometallic precursors show higher intrinsic activity than known materials and exhibit good reaction properties for synthesis gas production reactions at reaction conditions with high thermodynamic affinity for carbon species formation, e.g., low values ​​of S / C ratio and therefore low amounts of steam in the reagent mixture. In fact, it has been found that catalysts prepared by methods using organometallic precursors of elements such as Ni, Co, Fe and relatively small amounts of noble metals such as Rh, Ir, Ru are capable of carrying out the SR, SCR of CPO and SCT-CPO reactions under conditions where catalysts prepared by known methods are deactivated by the formation of carbonized residues.

[0048] The invention will now be described with reference to the following examples, which are provided as non-limiting examples. EXAMPLES

[0049] [Example 1 (Comparative)] The Ni / α-Al2O3 specimen was obtained by incipient wetness (IWI) impregnation followed by drying and calcination according to the scheme represented in Figure 1A. The incipient wetness impregnation was performed on a Ni / α-Al2O3 specimen with a diameter of 2 mm and a surface area of ​​11 m 2 / g, porosity 0.57 cm 3The IWI and drying procedure was repeated twice, and the samples were then heated to 750 °C for 2 h at a heating rate of 3 °C / min. After two IWI and drying procedures, the samples were heated to 750 °C for 2 h at a heating rate of 3 °C / min to decompose the nitrates. X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements revealed that Ni species existed mainly as NiO clusters with sizes of 15–25 nm. The obtained raw material contained 2.9 wt% Ni and needed to be reduced in a H2+N2 flow containing 10 v / v% H2, the temperature was increased between 25 and 500 °C at a heating rate of 3 °C / min, and the catalyst was left at 500 °C for 3 h. This treatment transformed the oxidized species of Ni on the surface of the α-Al2O3 support into aggregates of metallic Ni, generating catalytic active sites for synthesis gas production.

[0050] [Example 2 (Comparison)] Diameter 2 mm, surface area 11 m 2 / g, porosity 0.57 cm 3An aqueous solution containing Rh(NO3)2 (Rh 12.5 wt%) was dropped onto an α-Al2O3 sample consisting of spherical particles with a molecular weight of 1.0 g / g and an average pore diameter of 350 Å. The IWI process and drying / calcination heat treatment were performed according to the scheme in Figure 1A to obtain a Rh / α-Al2O3 sample. After impregnation, the sample was dried at 120 °C for 2 h with a heating rate of 3 °C / min. After repeating the IWI and drying procedure three times, the sample was heated to 750 °C with a heating rate of 3 °C / min and left at the maximum temperature for 2 h to decompose the nitrates. The final material, cooled to room temperature, contained 1.0 wt% Rh. XRD and SEM measurements revealed that Rh species existed as surface Rh2O3 clusters with a size of 10–50 nm. Before use in the synthesis gas production reaction, it was reduced in a H2+N2 flow containing 10 v / v% H2, the temperature was increased between 25 and 500 °C at a heating rate of 3 °C / min, and the catalyst was left at 500 °C for 3 h.

[0051] [Example 3 (Comparison)] Diameter 2 mm, surface area 11 m 2 / g, porosity 0.57 m 3 / g, α-Al consisting of spheres with an average pore diameter of 350 A 2 O 3 Two aqueous solutions of Ni(NO3)3 (Ni 27 wt%) and Rh(NO3)2 (Rh 12.5 wt%) were dropped onto the sample, and the IWI procedure and drying-calcination heat treatment were performed according to the scheme described in Figure 1A to obtain the Rh-Ni / α-Al2O3 sample. The volumes of the Ni(NO3)3 and Rh(NO3)3 solutions were adjusted to give Rh / Ni ratios of 0.25 g / g and 0.14 mol / mol. The sample was dried at 120 °C with a heating rate of 3 °C / min for 2 h, and the IWI and drying procedures were repeated twice. After that, the sample was heated at 750 °C with a heating rate of 3 °C / min for 2 h to decompose the nitrates. The final material, cooled to room temperature at 10 °C / min, contained 2.6 wt% Ni and 0.7 wt% Rh. XRD and SEM measurements revealed that the Ni species mostly existed as NiO species with sizes between 10 and 15 nm, while the Rh species mostly existed as surface Rh2O3 clusters with sizes difficult to estimate. Before use in the synthesis gas production reaction, it was reduced in a H2+N2 flow containing 10 v / v% H2, the temperature was increased between 25 and 500 °C with a heating rate of 3 °C / min, and the catalyst was left at 500 °C for 3 h.

[0052] [Examples 4 to 6] Samples of Rh, Ru and Ir deposited on α-Al2O3 supports (with the same characteristics as those described in Examples 1-3) were prepared to obtain catalysts containing 1 wt.% of precious metals. The procedure followed is depicted in the diagram of Figure 1B, and shows that the precious metal Rh4(CO) 12 Example 4: Ru(CO) 12 (Example 5) or Ir(CO) 12 The IWI step was carried out by dropping a solution of 10 wt% of (Example 6) in anhydrous THF onto the α-Al2O3 support. More specifically, the impregnation step by incipient wetness was carried out in a rotating vessel (20 rpm). The noble metal clusters reacted with the surface to produce a monolayer of surface species, mainly M(I) dicarbonyl (M=Rh, Ru, Ir), until the coordinatively unsaturated surface sites (cus) were consumed, and the excess metal clusters accumulated on the surface as physisorbed species. This information was obtained by performing diffuse reflectance infrared spectroscopy (DRIFT) on the samples thus obtained. The solvent was removed under a slight vacuum and the material was heated in air to 150 °C at a heating rate of 3 °C / min. During the heat treatment, the carbonyl clusters decomposed, mainly producing CO2 and H2O species, leaving small Rh aggregates on the surface of the α-Al2O3. The material obtained in this way did not require calcination or reduction in the flow treatment of hydrogen-containing mixtures and was used directly in the synthesis gas (SR, SCR, CPO, SCT-CPO) production reaction.

[0053] [Examples 7 to 12] The Rh-containing sample was prepared by the reaction of Rh4(CO) in n-hexane according to the scheme in Figure 1C. 12 The pellets were prepared at room temperature by adding dropwise a red solution of 5% Rh (5 wt%) to a suspension of the pelletized oxide in the same solvent. The pellets had a grain size of 2 mm and ranged from 5 to 20 μm. 2 The pellets consisted of i) α-Al2O3 (Example 7), ii) spinel oxide MgAlOx (Example 8), iii) CeO2 (Example 9), La2O3 (Example 10), and iv) ZrO2·3Y2O3·CeO2 (Examples 11-12). After the solid-liquid reaction of the solution containing the organometallic compounds with the oxidized surface, the solution containing the carbonyl clusters was decolorized. After 2 hours, the solid was isolated by filtration and dried under vacuum at room temperature. The DRIFT spectrum (diffuse reflectance infrared Fourier transform spectroscopy) of the sample thus obtained showed that Rh / MgAO x The sample is at 2085 cm -1 and 2008 cm -1 and 2090 cm for the Rh / α-Al2O3 sample. -1 and 2010 cm -1 Carbonyl stretching bands were observed at the surface of the polycrystalline oxide, and were assigned to the Rh(I)(CO)2 surface species formed by oxidative dissociation of rhodium clusters involving OH groups on the surface of the polycrystalline oxide. Rh4(CO) 12 + [M]-OH →[M]-0-Rh'(C0)2+ H2 + CO The IR spectra of Rh samples deposited on the CeO2, ZrO2·3Y2O3·CeO2 and ZrO2·3Y2O3 supports show a peak at 2095 cm -1 and 2010 cm -1 A peak attributable to the same Rh monometallic species was found at 2110 cm -1 A shoulder was found near the catalyst that could be assigned to a carbonyl complex with a rhodium atom in the oxidation state of +I or higher. The catalyst did not require further heat treatment before it could be used in the synthesis gas production reaction. The amount of Rh adsorbed on La2O3 and ZrO2·3Y2O3 was equivalent to 0.15 wt%. The amount of Rh adsorbed on ZrO2·3Y2O3·CeO2 was equivalent to 0.2%. xThe Rh content in the sample corresponded to 0.5 wt%, while the amounts of Rh in the α-Al2O3 and CeO2 samples corresponded to 0.3 and 0.4 wt%, respectively. These Rh contents and spectroscopic information indicated that this method produced 100% Rh dispersions on each sample, whose surfaces contained less than one monolayer of Rh.

[0054] [Example 13] The manufacturing procedure (D) described in FIG. 2 was adopted. First, a 2 mm diameter, 11 m surface area was prepared as in Examples 1 and 3. 2 / g, porosity 0.57 cm 3 The Ni / α-Al2O3 samples obtained by IWI were prepared using an aqueous solution of Ni(NO3)2 (Ni 27 wt %) dropped onto a spherical sample of α-Al2O3 with 100% CO2 / g. The impregnation process was repeated twice, each impregnation step being followed by a heat treatment at 120 °C for 2 h as described in Examples 1 and 3. The samples were then calcined at 750 °C for 2 h. After cooling, the material obtained was dissolved in Rh4(CO) in THF as in Example 4. 12 The catalyst was treated again with the IWI phase using a solution of 0.01% Ni and 0.01% Rh. The final impregnation step was followed by a vacuum drying step and a heat treatment at 120 °C for 2 h in air with a heating rate of 3 °C / min as described in Example 4. The final catalyst contained 2.9 wt% Ni and 0.9 wt% Rh and was used in a synthesis gas production reaction without further reduction steps.

[0055] [Example 14] The manufacturing procedure (E) described in FIG. 3 was adopted, and first, a 2 mm diameter, 11 m surface area was prepared as in Example 13. 2 / g, porosity 0.57 cm 3 Ni / α-Al2O3 samples were prepared by IWI using an aqueous solution of Ni(NO3)2 (Ni 27 wt%) dropped onto spherical samples of α-Al2O3 with 1.0 μm / g. The impregnation process was repeated twice, and each impregnation step was followed by a heat treatment at 120 °C for 2 h as described in Example 13. The samples were then calcined at 750 °C for 2 h and, after cooling, dissolved in Rh4(CO) in n-hexane. 12The catalyst was immersed in the solution and chemisorbed as in Examples 7-12, reacting with the coordinatively unsaturated sites (cus) on the α-Al2O3 / NiO surface. After 2 hours, the solid was isolated by filtration and dried at room temperature under vacuum. No other heat or reduction treatments were required for use in the synthesis gas production reaction. The final material contained 2.9 wt% Ni and 0.5 wt% Rh.

[0056] [Example 15] The preparation procedure (F) described in Figure 4 was adopted, using α-Al2O3 spheres as described in Examples 1-14 above for the first IWI step, but using a solution of Ni(acac)3 in THF. Samples were obtained by drying under vacuum and then heating to 150 °C for 2 h at a heating rate of 3 °C / min. After cooling, the spheres were dissolved in Rh4(CO) in n-hexane. 12 The catalyst was immersed in the solution to allow a solid-liquid reaction between the coordinatively unsaturated sites (cus) on the surface of Ni-containing α-Al2O3 and the carbonyl clusters. After 2 hours, the solid was isolated by filtration and dried under vacuum at room temperature. No other heat or reduction treatments were performed before the catalyst containing 2.7 wt% Ni and 0.5 wt% Rh was used in the synthesis gas production reaction.

[0057] [Example 16] The preparation procedures (F and D) described in Figures 4 and 2 were employed using the α-Al2O3 spheres described in Example 15 above in an initial IWI step with a solution of Ni(acac)3 in THF. The resulting sample was dried under vacuum and then heated to 150 °C for 2 h at a heating rate of 3 °C / min. After cooling, the spheres were dissolved in Rh4(CO) in n-hexane. 12 The initial immersion in the solution allowed for a solid-liquid reaction between the Ni-containing α-Al2O3 surface coordinatively unsaturated sites (cus) and the carbonyl clusters. After 2 h, the solid was isolated by filtration and dried under vacuum at room temperature. The dried sample was then dissolved in Ru3(CO) 12 The catalyst thus prepared, containing 2.6 wt% Ni, 0.4 wt% Rh, and 0.3 wt% Ru, was not subjected to any other heat or reduction treatment before being used in the synthesis gas production reaction.

[0058] [Example 17] The preparation procedures (F and D) described in Figures 4 and 2 were employed using α-Al2O3 spheres described in Examples 15 and 16 above in an initial IWI step using a solution of Ni(acac)3 in THF. The resulting samples were dried under vacuum and then heated to 150 °C for 2 h at a heating rate of 3 °C / min. After cooling, the spheres were dissolved in Rh4(CO) 12 The initial immersion in the solution allowed for a solid-liquid reaction between the Ni-containing α-Al2O3 surface coordinatively unsaturated sites (cus) and the carbonyl clusters. After 2 h, the solid was isolated by filtration and dried under vacuum at room temperature. The dried sample was then dissolved in Ir4(CO) 12 The catalyst thus prepared, containing 2.6 wt% Ni, 0.4 wt% Rh, and 0.3 wt% Ru, was treated by the IWI procedure using a solution of 1.0% Ni, 0.4 wt% Rh, and 0.3 wt% Ru in n-hexane. No other heat or reduction treatment was performed before the catalyst was used in the synthesis gas production reaction.

[0059] [Example 18] The preparation procedures (F and D) described in Figures 4 and 2 were employed using α-Al2O3 spheres as described in Examples 15-17 above in an initial IWI step using a solution of Ni(acac)3 and Co(acac) in THF. The resulting samples were dried under vacuum and then heated to 150 °C for 2 h at a heating rate of 3 °C / min. After cooling, the spheres were dissolved in Rh4(CO) in n-hexane. 12 The catalyst was first immersed in the solution to allow a solid-liquid reaction between the Ni-containing α-Al2O3 surface coordinatively unsaturated sites (cus) and the carbonyl clusters. After 2 h, the solid was isolated by filtration and dried under vacuum at room temperature. No other heat or reduction treatments were performed before the catalyst thus produced, containing 2 wt% Ni, 1 wt% Co, and 0.5 wt% Rh, was used in the synthesis gas production reaction.

[0060] [Examples 19 to 36: Reactivity tests of CO2 reforming and catalytic partial oxidation] Table 1 shows the catalyst composition and the main characteristics observed in the reactivity tests for the synthesis gas production reaction by CO2 reforming and CPO reaction.

[0061] [CO2 reforming test] Each test was performed for 100 hours in a plug flow reactor with an inner diameter of 15 mm under a pressure of 0.5 Mpa, and the length of the catalyst bed was 100 mm. The gas hourly space velocity value [GHSV = (NL x hours -1 of reagent) / L CAT] for 5000 hours 1 The temperature was adjusted to 750°C. Electrical preheating and reactor heating were adjusted to maintain the inlet temperature of the first layer of the catalyst bed at 750°C. The catalysts prepared in Examples 1-3 were pre-reduced with a flow rate of H2+90%N2, 10% and a heating cycle of 25-400°C for about 5 hours. The Ni-based catalyst prepared as in Example 1 was deactivated within 1 hour by the carbonization residue formation reaction. The Ni-Rh catalyst prepared in Example 3 was partially deactivated and contained 10.4 wt% carbonization residue during the 100 hour reaction after discharge. In contrast, catalysts containing the same amount of Ni-Rh metals prepared using organometallic carbonyl compounds had a much lower affinity for the coke formation reaction (see Examples 13, 14, 15 and Table 1). It should be noted that the Rh-containing catalysts (0.1–0.5% Rh deposited on α-Al2O3 and MgAlOx from organometallic precursors), as in Examples 4–15, were not deactivated despite not being activated by pretreatment of reduction with H2+N2, and maintained their reactivity characteristics with equilibrium approach values ​​below 5 °C. In this regard, the approach temperature to equilibrium (T approach CR and T approach SR ) is the temperature at which the experimental composition of the gas leaving the reactor is in equilibrium with the actual temperature of the gas leaving the reactor (Tg). eq ) is reported to be defined as the difference between the CH4 + CO2 = 2CO + 2H2DH° 298 = 247 kJ / mole (CR) CH4 + H2O = CO + 3H2DH° 298 = 206 kJ / mole (SR) ΔT approach SR = T g - Teq SR ΔT approach CR = T g - T eq SR

[0062] [SCT-CPO low contact time catalytic partial oxidation test] The reactivity test was carried out for 100 h under a pressure of 0.5 MPa, reactor outlet temperature of 750-850°C, CH4 / O2 / H2O = 2 / 1.2 / 1 v / v CH4 / O2 / CO2 = 2 / 1.2 / 1 v / v and GHSV = 85,000 h -1 The reagent mixture was preheated to 150° C. before entering the catalyst bed designed in a truncated cone shape, as described in WO97 / 37929 and dx.doi.org / 10.1021 / ie402463m, Ind. Eng. Chem. Ris. 2013, 52, 17023-17037. In particular, the inlet diameter of the truncated cone was 5 mm, the outlet diameter was 25 mm and the height of the truncated cone was 30 mm. The deactivation phenomenon due to the formation of carbonized residues is emphasized in examples 1 and 3 and to a lesser extent in examples 10 and 11 (see Table 1). It should be noted that in some reactivity tests, the approach to the equilibrium temperature showed negative values, indicating that the reaction occurred in localized regions where the catalyst surface temperature was higher than the gas outlet temperature, as discussed in dx.doi.org / 10.1021 / ie402463m, Ind. Eng. Chem. Ris. 2013, 52, 17023-17037. [Table 1]

Claims

1. 1. A method for preparing a catalyst for a chemical process comprising a catalytic species comprised of one or more transition metals or compounds of said transition metals supported on a support, the method comprising: a) preparing a solution in an organic solvent of an organometallic compound of the transition metal which produces the catalytic species and contacting said solution with said support, wherein said organometallic compound is selected from metal-carbonyl and complexes of the transition metal with organic ligands, and said support is selected from the group consisting of inorganic oxides, nitrides, oxynitrides, carbides, borides, and metal compounds having oxide structures formed on their surfaces; b) depositing said solution of an organometallic compound of said transition metal on the surface of said support by a chemisorption or physisorption process, said depositing being (i) contacting the solution of the organometallic compound of the transition metal by incipient wetness impregnation of the support with the solution of the organometallic compound of the transition metal; or (ii) dispersing the support in the solution of the organometallic compound of the transition metal; This is done by c) removing the organic solvent in the solution of the organometallic compound of the transition metal deposited on the surface of the support, and completely or partially decomposing the organometallic compound of the transition metal remaining on the surface of the support by at least one heat treatment, whereby one or more catalytic species of the transition metal are deposited on the support, wherein a step of separating the support from the solution of the organometallic compound of the transition metal is carried out prior to the heat treatment. Including, wherein, prior to carrying out step a) of contacting the support with a solution of an organometallic compound of said transition metal, a first loading of one or more transition metals is carried out on said support by impregnating said support with an aqueous solution of an inorganic salt of said transition metal or an organic solution of an organometallic compound of said transition metal, followed by drying and heating until decomposition of said organic salt or said organometallic compound and loading of said transition metal on said support, after which step a) is carried out on said support using an organic complex of a transition metal selected from Rh, Ru, Ir.

2. The metal-carbonyl is Rh 4 (CO) 12 , Rh 6 (CO) 16 , Ru 3 (CO) 12 , Ir 4 (CO) 12 , Fe 2 (CO) 9 , Fe 3 (CO) 12 , Co 2 (CO) 8 , Co 4 (CO) 12 , Co 6 (CO) 16 The method of claim 1 , wherein the compound is selected from the group consisting of:

3. 2. The method of claim 1, wherein the organometallic compound of the transition metal with an organic ligand is a complex, wherein the transition metal is selected from Co, Fe, Ni, Rh, Ru, Ir, Pt, Pd, and the ligand is a RCOCHCOR'- group, where R and R' may be the same or different and are C1-C6 alkyl groups, preferably C1-C6 alkyl groups bearing at least one methyl group.

4. The support is in the form of pellets or a monolithic structure, and is made of MgO, α-Al 2 O 3 , MgAlO x , CEO 2 , La 2 O 3 , ZrO 2 , TiO 2 2. The method of claim 1, wherein the SiO 2 is selected from the group consisting of FeCrAl alloys, perovskite, cordierite and FeCrAl alloys.

5. A catalyst obtained by the method according to any one of claims 1 to 4.

6. CO 2 Reforming, Steam-CO 2 6. Use of the catalyst according to claim 5 in reforming, steam reforming, catalytic partial oxidation and low contact time catalytic partial oxidation processes and in the production of synthesis gas.

7. 7. Use of the catalyst according to claim 6 in the production of synthesis gas, which reduces the conditions of thermodynamic affinity for the formation of carbonized residues and also reduces the ratio of water vapor atoms to carbon atoms and / or the ratio of oxygen atoms to carbon atoms in the reactant mixture.

Images