Ternary supported catalyst as well as preparation method and application thereof

Abstract

The invention provides a ternary supported catalyst and a preparation method and application thereof.The ternary supported catalyst comprises a carrier and an auxiliary loaded on the surface of the carrier, the carrier comprises In2O3 and an M-containing oxide, the M-containing oxide comprises ZrO2, Ga2O3 or ZnO, and the auxiliary comprises an Rh element, a Pd element and a Cu element; in the ternary supported catalyst, the content of an Rh element is 1 to 10 weight percent, the content of a Pd element is 0.1 to 5 weight percent, and the content of a Cu element is 0.8 to 10 weight percent. According to the ternary supported catalyst disclosed by the invention, three elements of Rh, Pd and Cu with specific contents are supported on a specific carrier, and the contents of the Rh, Pd and Cu elements in the catalyst are regulated, so that the ternary supported catalyst has the characteristics of high CO2 conversion rate, high methanol selectivity, high methanol space-time yield and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of catalysts, and relates to a ternary supported catalyst and a preparation method and application thereof. BACKGROUND

[0002] In current chemical production, methanol mainly relies on coal gasification and natural gas reforming conversion, which consumes a large amount of fossil fuels and is accompanied by high carbon emissions, causing a significant burden on the environment. With the increasingly serious problem of global warming, carbon dioxide reduction and resource utilization have become a research hotspot. CO2 hydrogenation to methanol as a green chemical technology has important economic and environmental value because it can convert greenhouse gas CO2 into high-value chemical methanol. Although this reaction is thermodynamically favorable, it is still challenging due to the lack of effective catalysts to achieve satisfactory reaction kinetics, and high-efficiency catalysts for CO2 hydrogenation to methanol need to be developed.

[0003] Traditional copper-based synthesis gas methanol synthesis catalysts have been widely studied in the process of CO2 hydrogenation. However, due to its significant activity in the reverse water gas shift (RWGS) reaction, it exhibits lower methanol selectivity, and due to the easy influence of the active phase on water and high temperature, the stability is seriously decreased. Therefore, the existing technology shifts its focus to non-copper-based catalysts. In recent years, indium oxide (In2O3) has been widely studied as a highly efficient catalyst for CO2 hydrogenation to methanol, and In2O3 exhibits higher methanol selectivity than Cu, Co or noble metal catalysts and higher catalytic activity than ZnO catalysts. In addition, In2O3 can be easily supported and modified to further promote the activation of CO2 and H2 and stabilize the key intermediates, providing broad potential for designing forward-looking catalysts for sustainable methanol production.

[0004] However, compared with Cu-based catalysts, the catalytic activity of In2O3-based catalysts is still low, so current research focuses on modifying In2O3-based catalysts through supports and additives to improve catalytic activity and methanol selectivity. For example, CN114367285A discloses a catalyst for carbon dioxide hydrogenation to methanol, which is composed of Pd x / (In2O3) y / (CeO2) z / (ZrO2) n , wherein x, y, z, n are the mass fractions of Pd, In2O3, CeO2, ZrO2, and the reasonable distribution of active components on the surface of the catalyst is achieved through component regulation, so that the catalyst has relatively optimal catalytic activity. The catalyst is prepared by a coprecipitation method with different supports, and then the active components are loaded on the supports by an impregnation method. Under test conditions, Pd5 / (In2O3) 10 / (CeO2)68 / (ZrO2) 17 The catalyst exhibits higher methanol space-time yield, but is limited to 30000h -1 The high space velocity research above lacks research on smaller space velocities.

[0005] For example, CN116135305A discloses a supported Re / In2O3 catalyst, a preparation method thereof and application thereof in CO2 hydrogenation to methanol. The catalyst comprises active component Re and carrier In2O3, wherein the Re element is atomically dispersed on the In2O3 carrier. Compared with the In2O3 catalyst alone, the Re / In2O3 catalyst can significantly improve the CO2 conversion rate and methanol selectivity. Under the conditions of 5 MPa, 300 DEG C and 24000 mL / (g.h), the CO2 single-pass conversion rate can reach 11.5%, the methanol selectivity is more than 80%, and the methanol space-time yield reaches 758 mg / (g.h). However, the CO2 single-pass conversion rate and methanol selectivity still need to be improved.

[0006] In summary, the In-based catalysts have been widely studied by means of dopant and carrier addition. However, the performance of the catalysts in CO2 hydrogenation to methanol still needs to be further improved. Therefore, it is still a difficult problem to be solved to develop a catalyst with high CO2 conversion rate, high methanol selectivity and long-term stability. SUMMARY

[0007] The purpose of the present application is to provide a ternary supported catalyst, a preparation method thereof and application thereof. The ternary supported catalyst is loaded with Rh, Pd and Cu elements in a specific content. The adsorption and activation capacity of CO2 and H2 is enhanced by the interaction between Rh, Pd and Cu elements and In2O3 and M-containing oxides, and by adjusting the content of Rh, Pd and Cu elements in the catalyst. The ternary supported catalyst can be used as a high-activity CO2 hydrogenation to methanol catalyst, and has the characteristics of high CO2 conversion rate, high methanol selectivity and high methanol space-time yield.

[0008] To achieve the purpose of the present application, the following technical solutions are adopted:

[0009] In a first aspect, the present application provides a ternary supported catalyst, which comprises a carrier and an additive supported on the surface of the carrier. The carrier comprises In2O3 and M-containing oxide, and the M-containing oxide comprises any one or a combination of at least two of ZrO2, Ga2O3 or ZnO. The additive comprises Rh, Pd and Cu elements.

[0010] The content of Rh element in the ternary supported catalyst is 1-10wt%, the content of Pd element is 0.1-5wt%, and the content of Cu element is 0.8-10wt%.

[0011] The application adopts In2O3 and M-containing oxide as a carrier, and the auxiliary agent loaded on the surface of the carrier as an active component, and the auxiliary agent includes specific content of Rh, Pd and Cu elements, the synergies among the three auxiliary agents, the carrier and the active component induce the formation of oxygen vacancies, significantly increase the active sites in the catalyst, stabilize the crystal structure of the catalyst, greatly improve the stability of the metal nanoparticles in the catalyst, effectively inhibit the deactivation of the active component at high temperature, and realize the efficient activation of CO2 and H2, so that the ternary supported catalyst provided by the application has the characteristics of high CO2 conversion rate, high methanol selectivity and high methanol space-time yield.

[0012] The content of Rh element in the ternary supported catalyst is 1-10wt%, for example, it can be 1wt%, 2.5wt%, 5wt%, 7.5wt%, 9wt% or 10wt%, but is not limited to the listed values, and other values not listed in the value range are also applicable, and preferably 1-2.5wt%.

[0013] In the ternary supported catalyst, the content of Rh element is in a specific content range, if the content of Rh element is too small, the active sites are insufficient, which leads to reduced catalytic efficiency, and if the content of Rh element is too large, the carrier surface is covered, which hinders the dispersion of other components and may cause agglomeration.

[0014] The content of Pd element in the ternary supported catalyst is 0.1-5wt%, for example, it can be 0.1wt%, 0.5wt%, 1wt%, 1.5wt%, 2wt%, 3wt%, 4wt% or 5wt%, but is not limited to the listed values, and other values not listed in the value range are also applicable, and preferably 0.8-1.0wt%.

[0015] In the ternary supported catalyst, the content of Pd element is in a specific content range, if the content of Pd element is too small, it is difficult to effectively promote the intermediate reaction step, which will reduce the reaction rate, and if the content of Pd element is too large, it will compete with Rh layer or Cu layer for adsorption, which will destroy the multi-layer synergistic effect.

[0016] The content of Cu element in the ternary supported catalyst is 0.8-10wt%, for example, it can be 0.8wt%, 1.5wt%, 3wt%, 4.5wt%, 6wt%, 7wt%, 8wt%, 9wt% or 10wt%, but is not limited to the listed values, and other values not listed in the value range are also applicable, and preferably 1.5-5.2wt%.

[0017] The content of Cu element in the ternary supported catalyst is in a specific range, if the content of Cu element is too low, the surface structure cannot be sufficiently stabilized or the product selectivity cannot be optimized, and if the content of Cu element is too high, the catalyst pores are blocked, limiting the diffusion of reactants and the exposure of active sites.

[0018] Preferably, the content of In2O3 in the ternary supported catalyst is 1-15wt%, for example, it can be 1wt%, 2.5wt%, 4wt%, 6.5wt%, 8wt%, 11wt%, 13.5wt%, 14wt% or 15wt%, but is not limited to the listed values, and other values not listed in the value range are also applicable, and preferably 10-15wt%.

[0019] Preferably, the content of the oxide containing M in the ternary supported catalyst is 60-97.6wt%, for example, it can be 60wt%, 75wt%, 80wt%, 85wt%, 95wt% or 97.6wt%, but is not limited to the listed values, and other values not listed in the value range are also applicable, and preferably 60-86wt%.

[0020] Preferably, the ternary supported catalyst comprises a carrier, a first supported layer supported on the surface of the carrier, a second supported layer on the surface of the first supported layer, and a third supported layer on the surface of the second supported layer, the first supported layer comprises Rh element, the second supported layer comprises Pd element, and the third supported layer comprises Cu element.

[0021] The three elements of Rh element, Pd element and Cu element are distributed at specific positions of the carrier, wherein, since Rh element has high adsorption capacity and can preferentially activate reactants, it is closest to the carrier and is located in the first supported layer on the surface of the carrier; since Pd element has redox characteristics and can promote the conversion of intermediate products, it is located in the second supported layer away from the surface of the carrier; and since Cu element has an electronic regulation effect and can optimize product desorption and inhibit side reactions such as excessive hydrogenation, it is located in the third supported layer.

[0022] In a second aspect, the application provides a preparation method of the ternary supported catalyst according to the first aspect, the preparation method comprising the following steps:

[0023] The carrier, the Rh source, the Pd source, the Cu source and the solvent are mixed, rested, dried and calcined according to the formula amount, so as to obtain the ternary supported catalyst.

[0024] The ternary supported catalyst is prepared by the impregnation method.

[0025] Preferably, the steps of mixing, resting, drying and calcining the carrier, the Rh source, the Pd source, the Cu source and the solvent comprise:

[0026] The carrier, the Rh source and the solvent are mixed, rested, dried and calcined once to obtain the Rh-loaded carrier;

[0027] The Rh-loaded carrier, the Pd source and the solvent are mixed, rested, dried and calcined twice to obtain the Rh and Pd-loaded carrier;

[0028] The Rh and Pd-loaded carrier, the Cu source and the solvent are mixed, rested, dried and calcined thrice to obtain the ternary supported catalyst.

[0029] The ternary supported catalyst with specific structure is prepared by the step-by-step impregnation method in order to distribute Rh, Pd and Cu in specific positions.

[0030] Preferably, the Rh source comprises any one or a combination of at least two of rhodium chloride, rhodium nitrate or rhodium acetate.

[0031] Preferably, the Pd source comprises any one or a combination of at least two of palladium chloride, palladium nitrate or palladium acetate.

[0032] Preferably, the Cu source comprises any one or a combination of at least two of copper sulfate, copper nitrate or copper acetate.

[0033] Preferably, the solvent comprises deionized water.

[0034] Preferably, the resting time of the first, second and third resting is independently 1-4h, for example, 1h, 2h, 2.5h, 3.0h or 4.0h, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0035] Preferably, the mixing temperature of the first, second and third mixing is independently 70-90℃, for example, 70℃, 80℃ or 90℃, the stirring rate is independently 200-400rpm, for example, 200rpm, 300rpm or 400rpm, and the time is independently 2-4h, for example, 2h, 3h or 4h, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0036] Preferably, the temperature of the first drying is 80-150°C, for example it can be 80°C, 85°C, 90°C, 100°C, 105°C, 115°C, 125°C or 130°C, but is not limited to the listed values, other values not listed within the range of values are equally applicable, preferably 80-130°C.

[0037] Preferably, the time of the first drying is 8-15h, for example it can be 8h, 10h, 12h, 13h or 15h, but is not limited to the listed values, other values not listed within the range of values are equally applicable, preferably 8-12h.

[0038] Preferably, the temperature of the first firing is 300-500°C, for example it can be 300°C, 350°C, 400°C, 450°C or 500°C, but is not limited to the listed values, other values not listed within the range of values are equally applicable, preferably 380-450°C.

[0039] Preferably, the time of the first firing is 3-8h, for example it can be 3h, 4h, 5h, 7h or 8h, but is not limited to the listed values, other values not listed within the range of values are equally applicable.

[0040] Preferably, the temperature of the second drying is 80-120°C, for example it can be 80°C, 85°C, 90°C, 100°C, 105°C, 115°C or 120°C, but is not limited to the listed values, other values not listed within the range of values are equally applicable, preferably 80-110°C.

[0041] Preferably, the time of the second drying is 6-13h, for example it can be 6h, 8h, 10h, 12h or 13h, but is not limited to the listed values, other values not listed within the range of values are equally applicable, preferably 6-12h.

[0042] Preferably, the temperature of the second firing is 240-450°C (preferably 300-400°C), for example it can be 250°C, 300°C, 350°C, 400°C or 450°C, and the time is 2-6h (preferably 2-4h), for example it can be 2h, 3h, 4h, 5h or 6h, but is not limited to the listed values, other values not listed within the range of values are equally applicable.

[0043] Preferably, the temperature of the third drying is 60-110°C (preferably 80-105°C), for example it can be 60°C, 70°C, 80°C, 90°C, 105°C or 110°C, and the time is 8-15h (preferably 8-12h), for example it can be 8h, 10h, 12h, 13h or 15h, but is not limited to the listed values, other values not listed within the range of values are equally applicable.

[0044] Preferably, the temperature of the third calcination is 200-400℃ (preferably 250-350℃), for example, it can be 200℃, 250℃, 300℃, 350℃ or 400℃, and the time is 2-6h (preferably 2-4h), for example, it can be 2h, 3h, 4h, 5h or 6h, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0045] Preferably, the method for preparing the carrier comprises the following steps:

[0046] The mixed metal salt solution and the precipitant are mixed to carry out a precipitation reaction and aging to obtain a reaction product, and the reaction product is washed, dried and sintered to obtain the carrier.

[0047] The mixed metal salt solution comprises In ions and M ions, and the M ions comprise any one or a combination of at least two of Zr ions, Ga ions or Zn ions.

[0048] The present application adopts a co-precipitation method to prepare a carrier containing In and M.

[0049] Preferably, the end point pH of the precipitation reaction is 8.5-10.5, for example, it can be 8.5, 8.8, 9.1, 9.4, 9.7, 10.0, 10.2, 10.3, 10.4 or 10.5, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0050] The end point pH of the precipitation reaction of the present application refers to the pH of the reaction solution after the precipitation is completed.

[0051] Preferably, the temperature of the precipitation reaction is 60-80℃, for example, it can be 60℃, 65℃, 70℃, 75℃ or 80℃, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0052] Preferably, the aging time (carried out under static state) is 1.5-3h, for example, it can be 1.5h, 2h, 2.5h or 3.0h, but is not limited to the listed values, and other values not listed in the value range are also applicable.

[0053] Preferably, the heating rate of the sintering is 1-5℃ / min, for example, it can be 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min or 5℃ / min, the temperature is 300-600℃, for example, it can be 300℃, 350℃, 400℃, 450℃, 500℃, 520℃, 550℃, 580℃ or 600℃, the holding time is 2-5h, for example, it can be 2h, 2.5h, 3h, 3.5h, 4h, 4.5h or 5h, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0054] Preferably, the mixed metal salt solution is mixed by an indium source, an M source and deionized water, the indium source includes any one or a combination of at least two of indium nitrate, indium sulfate or indium acetate, the M source includes any one or a combination of at least two of a zirconium source, a gallium source or a zinc source, the zirconium source includes any one or a combination of at least two of zirconium oxynitrate, zirconium sulfate or zirconium chloride, the gallium source includes any one or a combination of at least two of gallium nitrate, gallium sulfate or gallium acetate, the zinc source includes any one or a combination of at least two of zinc nitrate, zinc acetate or zinc chloride.

[0055] Preferably, the precipitant includes any one or a combination of at least two of sodium carbonate solution, ammonium carbonate solution, ammonium acetate solution or sodium hydroxide solution, wherein the mass fraction of the sodium hydroxide solution is 3-18wt%, for example, it can be 3wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 12wt%, 15wt%, 16wt%, 17wt% or 18wt%, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0056] Preferably, the mixing of the mixed metal salt solution and the precipitant includes dropping the precipitant into the mixed metal salt solution at 60-80℃, for example, it can be 60℃, 62℃, 65℃, 70℃, 75℃ or 80℃.

[0057] Preferably, the washing liquid used in the washing includes deionized water at 60-80℃, for example, it can be 60℃, 65℃, 70℃, 75℃, 78℃ or 80℃, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0058] Preferably, the drying temperature is 80-110℃, for example, it can be 80℃, 85℃, 90℃, 95℃, 100℃, 102℃, 106℃, 109℃ or 110℃, and the time is 6-12h, for example, it can be 6h, 8h, 9h, 10h or 12h, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0059] In a third aspect, the present application provides an application of the ternary supported catalyst as described in the first aspect, the application comprising a use for synthesizing methanol by CO2 hydrogenation.

[0060] Compared with the prior art, the present application has the following beneficial effects:

[0061] The ternary supported catalyst with the specific composition of the present application can exert a synergistic effect between components, induce the formation of oxygen vacancies, promote the increase of active sites, greatly improve the stability of metal nanoparticles, and effectively inhibit the deactivation of active components at high temperatures, thereby realizing the efficient activation of CO2 and H2. Therefore, compared with traditional monocomponent or bicomponent supported catalysts, the ternary supported catalyst of the present application significantly improves the catalytic activity of the catalyst while maintaining or even greatly improving the high selectivity advantage of traditional In-based catalysts, realizes high methanol space-time yield, and the stability of the catalyst is also obviously improved. Under the condition of 5 MPa, 300℃ and 12000 mL / (g cat ·h), the CO2 conversion rate can be as high as 18.5%, the methanol selectivity can be as high as 86.52%, and the methanol space-time yield can be as high as 658.54 mg MeOH / (g cat ·h). DETAILED DESCRIPTION

[0062] The technical solutions of the present application will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only used to help understand the present application and should not be regarded as specific limitations on the present application.

[0063] Embodiment 1

[0064] The present embodiment provides a ternary supported catalyst, the ternary supported catalyst comprising a carrier supported catalyst including a carrier, a first support layer supported on the surface of the carrier, a second support layer on the surface of the first support layer, and a third support layer on the surface of the second support layer, wherein the carrier comprises In2O3 and ZrO2, the first support layer comprises Rh element, the second support layer comprises Pd element, and the third support layer comprises Cu element.

[0065] The ternary supported catalyst is specifically a 1wt%Rh-0.8wt%Pd-1.5wt%Cu / 12wt%In2O3 / 84.7wt%ZrO2 catalyst, wherein the content of Rh is 1.0wt%, the content of Pd element is 0.8wt%, the content of Cu is 1.5wt%, the content of In2O3 is 12wt%, and the content of ZrO2 is 84.7wt%.

[0066] The preparation method of the ternary supported catalyst comprises the following steps:

[0067] (1) Weigh indium nitrate and zirconyl nitrate according to the formula amount, dissolve in deionized water to obtain a precursor solution;

[0068] 20 g of sodium hydroxide is added to deionized water to prepare a 15 wt% alkaline precipitant solution. At 70°C, the above precipitant solution is slowly added to the precursor solution to carry out the precipitation reaction, and the end point pH of the precipitation reaction is controlled at 9.5. After the addition is completed, the stirring is continued for 30 min to obtain a suspension, and then the suspension is aged for 2 h to obtain a precipitate product;

[0069] The precipitate product is repeatedly washed with deionized water until the last washing solution is neutral. Then, the precipitate product is placed in an oven and dried at 80°C for 10 h. Then, the temperature is increased to 550°C at a rate of 5°C / min and calcined for 4 h to obtain a carrier;

[0070] (2) Then, the carrier prepared above is ground into a powder that passes through a 60 mesh sieve but does not pass through an 80 mesh sieve. The powder is added to the nitrate precursor solution of Rh, stirred at 300 rpm at 80°C for 3 h, then immersed at room temperature for 2 h, and then dried at 100°C for 10 h. The large sample after drying is broken, and the temperature is increased to 450°C at a rate of 5°C / min at room temperature and calcined for 5 h to obtain a Rh / In2O3-ZrO2 catalyst containing a first loading layer of Rh;

[0071] (3) The Rh / In2O3-ZrO2 catalyst containing the first loading layer of Rh is added to the nitrate precursor solution of Pd, stirred at 300 rpm at 80°C for 3 h, then immersed at room temperature for 2 h, dried at 80°C for 12 h, and the large sample after drying is broken. The temperature is increased to 350°C at a rate of 5°C / min at room temperature and calcined for 3 h to obtain a second loading layer of Pd in the Rh / In2O3-ZrO2 catalyst containing the first loading layer of Rh;

[0072] (4) The catalyst obtained in step (3) is added to the nitrate precursor solution of Cu, stirred at 300 rpm at 80°C for 3 h, then immersed at room temperature for 2 h, and then dried at 105°C for 10 h. The large sample after drying is broken, and the temperature is increased to 330°C at a rate of 5°C / min at room temperature and calcined for 3 h to obtain the ternary supported catalyst.

[0073] Example 2

[0074] The embodiment provides a ternary supported catalyst, and the ternary supported catalyst comprises a carrier supported catalyst comprising a carrier, a first supported layer supported on the surface of the carrier, a second supported layer on the surface of the first supported layer, and a third supported layer on the surface of the second supported layer, wherein the carrier comprises In2O3 and ZrO2, the first supported layer comprises Rh elements, the second supported layer comprises Pd elements, and the third supported layer comprises Cu elements.

[0075] The ternary supported catalyst is specifically a 1wt% Rh-0.1wt% Pd-1.5wt% Cu / 12wt% In2O3 / 85.4wt% ZrO2 catalyst, wherein the content of Rh is 1.0wt%, the content of Pd elements is 0.1wt%, the content of Cu is 1.5wt%, the content of In2O3 is 12wt%, and the content of ZrO2 is 85.4wt%.

[0076] The preparation method of the ternary supported catalyst comprises the following steps:

[0077] (1) Indium nitrate and zirconyl nitrate are weighed according to the formula amount and dissolved in deionized water to obtain a precursor solution;

[0078] 20g of sodium hydroxide is configured into an 18wt% alkaline precipitant solution, and the precipitant solution is slowly dropped into the precursor solution at 60°C to perform a precipitation reaction, the end point pH of the precipitation reaction is controlled to be 10.5, after the dropping is completed, the stirring is continued for 30min to obtain a suspension, and then the suspension is aged for 1.5h to obtain a precipitate product;

[0079] After the precipitate product is repeatedly washed with deionized water until the last washing liquid is neutral, the precipitate product is placed in an oven for drying at 110°C for 6h, and then the temperature is increased to 300°C at a temperature increasing rate of 3°C / min for calcination for 5h to obtain a carrier;

[0080] (2) Then, a nitrate precursor solution of Rh, Pd and Cu in a corresponding proportion is configured according to the content of Rh, Pd and Cu, the carrier prepared in the above is ground into a powder that passes through a 60-mesh sieve but does not pass through an 80-mesh sieve, and the powder is added into the nitrate precursor solution of Rh, and stirred at 200rpm at 90°C for 4h, and then the impregnation is performed at room temperature for 4h, and then the large block sample after drying is broken, and the temperature is increased to 500°C at a temperature increasing rate of 5°C / min at room temperature for calcination for 3h to obtain a Rh / In2O3-ZrO2 catalyst with a first supported layer containing Rh elements;

[0081] (3) adding the Rh / In2O3-ZrO2 catalyst with the first loading layer containing Rh into a nitrate precursor solution of Pd, stirring at 200 rpm for 4 h at 90℃, then standing for impregnation at room temperature for 1 h, drying at 120℃ for 6 h, crushing the large sample after drying, and calcining at a temperature increasing rate of 5℃ / min to 450℃ for 2 h at room temperature, to obtain the second loading layer containing Pd in the Rh / In2O3-ZrO2 catalyst with the first loading layer containing Rh;

[0082] (4) adding the catalyst obtained in step (3) into a nitrate precursor solution of Cu, stirring at 400 rpm for 2 h at 70℃, then standing for impregnation at room temperature for 4 h, and drying at 60℃ for 15 h, crushing the large sample after drying, and calcining at a temperature increasing rate of 5℃ / min to 200℃ for 6 h at room temperature, to obtain the ternary supported catalyst.

[0083] Example 3

[0084] The embodiment provides a ternary supported catalyst, the ternary supported catalyst comprising a carrier supported catalyst including a carrier, a first loading layer supported on the surface of the carrier, a second loading layer on the surface of the first loading layer, and a third loading layer on the surface of the second loading layer, wherein the carrier comprises In2O3 and ZrO2, the first loading layer comprises Rh elements, the second loading layer comprises Pd elements, and the third loading layer comprises Cu elements.

[0085] The ternary supported catalyst is specifically a 1wt% Rh-0.8wt% Pd-1.5wt% Cu / 12wt% In2O3 / 84.7wt% ZrO2 catalyst, wherein the content of Rh is 1.0wt%, the content of Pd elements is 0.8wt%, the content of Cu is 1.5wt%, the content of In2O3 is 12wt%, and the content of ZrO2 is 84.7wt%.

[0086] The preparation method of the ternary supported catalyst comprises the following steps:

[0087] (1) weighing indium nitrate and zirconyl nitrate according to the formula amount, and dissolving in deionized water to obtain a precursor solution;

[0088] 20g of sodium hydroxide is configured into a 3wt% alkaline precipitator solution, and the precipitator solution is slowly dropped into the precursor solution at 80℃ for a precipitation reaction, the end point pH of the precipitation reaction is controlled to be 8.5, and after the dropping is completed, the stirring is continued for 30 min to obtain a suspension, and then the suspension is aged for 3h to obtain a precipitate;

[0089] The precipitated product was washed repeatedly with deionized water until the last washing liquid was neutral, dried in an oven at 100°C for 12h, then heated to 600°C at a heating rate of 1°C / min and calcined for 2h to obtain the carrier;

[0090] (2) The carrier prepared above was ground into a powder that passed through a 60 mesh sieve but not through an 80 mesh sieve, and then added to a nitrate precursor solution of Rh at a corresponding proportion. The mixture was stirred at 70°C at 400 rpm for 2h, then left to stand at room temperature for 1h of impregnation, and then dried at 80°C for 15h. The dried bulk sample was crushed, and then heated to 300°C at a heating rate of 5°C / min and calcined for 8h at room temperature to obtain a Rh / In2O3-ZrO2 catalyst with a first loading layer of Rh;

[0091] (3) The Rh / In2O3-ZrO2 catalyst with the first loading layer of Rh was added to a nitrate precursor solution of Pd, and the mixture was stirred at 70°C at 400 rpm for 2h, then left to stand at room temperature for 4h of impregnation, and then dried at 100°C for 13h. The dried bulk sample was crushed, and then heated to 240°C at a heating rate of 5°C / min and calcined for 6h at room temperature to obtain a second loading layer of Pd in the Rh / In2O3-ZrO2 catalyst with the first loading layer of Rh;

[0092] (4) The catalyst obtained in step (3) was added to a nitrate precursor solution of Cu, and the mixture was stirred at 90°C at 200 rpm for 4h, then left to stand at room temperature for 1h of impregnation, and then dried at 110°C for 8h. The dried bulk sample was crushed, and then heated to 400°C at a heating rate of 5°C / min and calcined for 2h at room temperature to obtain the ternary supported catalyst.

[0093] Example 4

[0094] The ternary supported catalyst provided in this example is identical to that of Example 1 except that the specific formula is 2.5wt% Rh-5.0wt% Pd-1.0wt% Cu / 10wt% In2O3 / 81.5wt% ZrO2, the content of Rh is 2.5wt%, the content of Pd is 5.0wt%, the content of Cu is 1.0wt%, the content of In2O3 is 10.0wt%, and the content of ZrO2 is 81.5wt%.

[0095] The preparation method of the ternary supported catalyst is identical to that of Example 1 except that the formula is adapted.

[0096] Example 5

[0097] The embodiment provides a ternary supported catalyst, which is 10wt% Rh-5wt% Pd-10wt% Cu / 15wt% In2O3 / 60wt% ZrO2 except that the content of Rh is 10wt%, the content of Pd element is 5.0wt%, the content of Cu is 10wt%, the content of In2O3 is 15wt%, and the content of ZrO2 is 60wt%, and the rest is the same as in embodiment 1;

[0098] The preparation method of the ternary supported catalyst is the same as in embodiment 1 except that the formula amount is adaptively changed.

[0099] Embodiment 6

[0100] The embodiment provides a ternary supported catalyst, which is 2wt% Rh-1.1wt% Pd-1wt% Cu / 10wt% In2O3 / 85.9wt% ZrO2 except that the content of Rh is 2wt%, the content of Pd element is 1.1wt%, the content of Cu is 1wt%, the content of In2O3 is 10wt%, and the content of ZrO2 is 85.9wt%, and the rest is the same as in embodiment 1;

[0101] The preparation method of the ternary supported catalyst is the same as in embodiment 1 except that the formula amount is adaptively changed.

[0102] Embodiment 7

[0103] The embodiment provides a ternary supported catalyst, which is 1wt% Rh-0.8wt% Pd-0.8wt% Cu / 12wt% In2O3 / 85.4wt% ZrO2 except that the content of Rh is 1wt%, the content of Pd element is 0.8wt%, the content of Cu is 0.8wt%, the content of In2O3 is 12wt%, and the content of ZrO2 is 85.4wt%, and the rest is the same as in embodiment 1;

[0104] The preparation method of the ternary supported catalyst is the same as in embodiment 1 except that the formula amount is adaptively changed.

[0105] Embodiment 8

[0106] The embodiment provides a ternary supported catalyst, which is the same as that in the embodiment 1 except that the ternary supported catalyst is 1wt% Rh-0.8wt% Pd-5.2wt% Cu / 12wt% In2O3 / 81wt% ZrO2, the content of Rh is 1wt%, the content of Pd is 0.8wt%, the content of Cu is 5.2wt%, the content of In2O3 is 12wt%, and the content of ZrO2 is 81wt%.

[0107] The preparation method of the ternary supported catalyst is the same as that in the embodiment 1 except that the formula amount is adaptively changed.

[0108] Embodiment 9

[0109] The embodiment provides a ternary supported catalyst, which is the same as that in the embodiment 1 except that the ternary supported catalyst is 1wt% Rh-1wt% Pd-1.5wt% Cu / 12wt% In2O3 / 84.5wt% Ga2O3, the content of Rh is 1wt%, the content of Pd is 1wt%, the content of Cu is 1.5wt%, the content of In2O3 is 12wt%, and the content of Ga2O3 is 84.5wt%.

[0110] The preparation method of the ternary supported catalyst is the same as that in the embodiment 1 except that the formula amount is adaptively changed.

[0111] Embodiment 10

[0112] The embodiment provides a ternary supported catalyst, which is the same as that in the embodiment 1 except that the ternary supported catalyst is 2wt% Rh-0.8wt% Pd-1wt% Cu / 12wt% In2O3 / 84.2wt% ZnO, the content of Rh is 2wt%, the content of Pd is 0.8wt%, the content of Cu is 1.0wt%, the content of In2O3 is 12wt%, and the content of ZnO is 84.2wt%.

[0113] The preparation method of the ternary supported catalyst is the same as that in the embodiment 1 except that the formula amount is adaptively changed.

[0114] Embodiment 11

[0115] The embodiment provides a ternary supported catalyst, which is the same as that in the embodiment 1 except that the first supported layer comprises Pd elements and the second supported layer comprises Rh elements.

[0116] The preparation method of the ternary supported catalyst is the same as that in the embodiment 1 except that the impregnation sequence of Rh and Pd is changed.

[0117] Example 12

[0118] This example provides a ternary supported catalyst, which is identical to Example 1 except that the first supported layer includes Cu element and the third supported layer includes Rh element.

[0119] The preparation method of the ternary supported catalyst is identical to Example 1 except that the Rh and Cu impregnation sequence is changed.

[0120] Example 13

[0121] This example provides a ternary supported catalyst, which is identical to Example 1 except that the second supported layer includes Cu element and the third supported layer includes Pd element.

[0122] The preparation method of the ternary supported catalyst is identical to Example 1 except that the Pd and Cu impregnation sequence is changed.

[0123] Comparative Example 1

[0124] This comparative example provides a supported catalyst, which is identical to Example 1 except that the specific formula is 1wt% Rh-1.3wt% Cu / 12wt% In2O3 / 85.7wt% ZrO2, the content of Rh is 1wt%, the content of Cu is 1.3wt%, the content of In2O3 is 12.0wt%, and the content of ZrO2 is 85.7wt%;

[0125] The preparation method of the supported catalyst is identical to Example 1 except that the formula amount is adaptively changed.

[0126] Comparative Example 2

[0127] This comparative example provides a supported catalyst, which is identical to Example 1 except that the specific formula is 1wt% Rh-0.8wt% Pd / 12wt% In2O3 / 86.2wt% ZrO2, the content of Rh is 1wt%, the content of Pd element is 0.8wt%, the content of In2O3 is 12wt%, and the content of ZrO2 is 86.2wt%;

[0128] The preparation method of the supported catalyst is identical to Example 1 except that the formula amount is adaptively changed.

[0129] Comparative Example 3

[0130] This comparative example provides a supported catalyst, which is the same as in Example 1 except that it is composed of 0.8wt% Pd-1.5wt% Cu / 12wt% In2O3 / 85.7wt% ZrO2, with the Pd content being 0.8wt%, the Cu content being 1.5wt%, the In2O3 content being 12wt%, and the ZrO2 content being 85.7wt%.

[0131] The preparation method of the supported catalyst is the same as that in Example 1, except that the formulation amount is adapted to change.

[0132] Comparative Example 4

[0133] This comparative example provides a supported catalyst, which is the same as in Example 1 except that it is specifically composed of 1wt% Rh-0.8wt% Pd-1.5wt% Cu / 96.7wt% ZrO2, with the Rh content being 1wt%, the Pd content being 0.8wt%, the Cu content being 1.5wt%, and the ZrO2 content being 96.7wt%.

[0134] The preparation method of the supported catalyst is the same as that in Example 1, except that the formulation amount is adapted to change.

[0135] Comparative Example 5

[0136] This comparative example provides a supported catalyst, which is the same as in Example 1 except that it is specifically composed of 1wt% Rh-0.8wt% Ni-1.5wt% Cu / 12wt% In2O3 / 84.7wt% ZrO2, with Rh content of 1wt%, Ni content of 0.8wt%, Cu content of 1.5wt%, In2O3 content of 12wt%, and ZrO2 content of 84.7wt%.

[0137] The preparation method of the supported catalyst is the same as that in Example 1, except that the formulation amount is adapted to change.

[0138] Comparative Example 6

[0139] This comparative example provides a supported catalyst, which is the same as in Example 1 except that it contains 0.1wt% Rh-0.8wt% Pd-1.5wt% Cu / 12wt% In2O3 / 85.6wt% ZrO2, with Rh content of 0.1wt%, Pd content of 0.8wt%, Cu content of 1.5wt%, In2O3 content of 12wt%, and ZrO2 content of 85.6wt%.

[0140] The preparation method of the supported catalyst is the same as that of Example 1 except that the formulation amount is adaptively changed.

[0141] Comparative Example 7

[0142] This comparative example provides a supported catalyst which is the same as that of Example 1 except that the specific formulation is 15wt% Rh-0.8wt% Pd-1.5wt% Cu / 12wt% In203 / 70.7wt% Zr02, the content of Rh is 15wt%, the content of Pd element is 0.8wt%, the content of Cu is 1.5wt%, the content of In203is 12wt%, and the content of Zr02is 70.7wt%;

[0143] The preparation method of the supported catalyst is the same as that of Example 1 except that the formulation amount is adaptively changed.

[0144] Comparative Example 8

[0145] This comparative example provides a supported catalyst which is the same as that of Example 1 except that the specific formulation is 1wt% Rh-0.01wt% Pd-1.5wt% Cu / 12wt% In203 / 85.49wt% Zr02, the content of Rh is 1wt%, the content of Pd element is 0.01wt%, the content of Cu is 1.5wt%, the content of In203is 12wt%, and the content of Zr02is 85.49wt%;

[0146] The preparation method of the supported catalyst is the same as that of Example 1 except that the formulation amount is adaptively changed.

[0147] Comparative Example 9

[0148] This comparative example provides a supported catalyst which is the same as that of Example 1 except that the specific formulation is 1wt% Rh-8wt% Pd-1.5wt% Cu / 12wt% In203 / 77.5wt% Zr02, the content of Rh is 1wt%, the content of Pd element is 8wt%, the content of Cu is 1.5wt%, the content of In203is 12wt%, and the content of Zr02is 77.5wt%;

[0149] The preparation method of the supported catalyst is the same as that of Example 1 except that the formulation amount is adaptively changed.

[0150] Comparative Example 10

[0151] This comparative example provides a supported catalyst, which is the same as in Example 1 except that it is specifically composed of 1wt% Rh-0.8wt% Pd-0.1wt% Cu / 12wt% In2O3 / 86.1wt% ZrO2, with Rh content of 1wt%, Pd content of 0.8wt%, Cu content of 0.1wt%, In2O3 content of 12wt%, and ZrO2 content of 86.1wt%.

[0152] The preparation method of the supported catalyst is the same as that in Example 1, except that the formulation amount is adapted to change.

[0153] Comparative Example 11

[0154] This comparative example provides a supported catalyst, which is the same as in Example 1 except that it is composed of 1wt% Rh-0.8wt% Pd-15wt% Cu / 12wt% In2O3 / 71.2wt% ZrO2, with Rh content of 1wt%, Pd content of 0.8wt%, Cu content of 15wt%, In2O3 content of 12wt%, and ZrO2 content of 71.2wt%.

[0155] The preparation method of the supported catalyst is the same as that in Example 1, except that the formulation amount is adapted to change.

[0156] The catalysts obtained in the above examples and comparative examples were ground and sieved into powder that passed through a 60-mesh sieve but not an 80-mesh sieve, and then their activity was evaluated. In the catalyst activity evaluation, the reaction of carbon dioxide hydrogenation to methanol was carried out in a fixed-bed reactor. After reduction with pure hydrogen at 300°C for 2 hours, the temperature was lowered to the reaction temperature, and the reaction was switched to reactant gases (H2: 69 vol%; CO2: 23 vol%; N2: 8 vol%). The reaction conditions were as follows: P = 5 MPa, T = 300°C, GHSV = 12000 h⁻¹. -1 The ratio of n(H2):n(CO2) is 3:1. The test results and the content of each component of the catalyst obtained in the above examples and comparative examples are shown in Table 1.

[0157] Table 1

[0158]

[0159]

[0160] As can be seen from Table 1:

[0161] As can be seen from the embodiment 1 and the comparative examples 1-5, the three elements of Rh, Pd and Cu are loaded on the carrier including In2O3 and the oxide containing M, so that the catalytic performance, the selectivity to methanol and the methanol space-time yield of the catalyst can be effectively improved; as can be seen from the embodiment 1, the embodiment 4-10 and the comparative examples 6-11, when the content of the three elements of Rh, Pd and Cu in the ternary supported catalyst varies, the catalytic activity of the catalyst has obvious difference, in order to simultaneously ensure the catalytic performance, the selectivity to methanol and the methanol space-time yield of the catalyst, the content of Rh is 1-10wt%, the content of Pd is 0.1-5wt% and the content of Cu is 0.8-10wt% in the ternary supported catalyst; as can be seen from the embodiment 1 and the embodiment 11-13, the Rh is preferably in the first loading layer of the catalyst, the Pd is preferably in the second loading layer of the catalyst and the Cu is preferably in the third loading layer of the catalyst, so that the synergistic effect among Rh, Pd and Cu can be further played and the performance of the catalyst can be improved.

[0162] The above merely provides the specific implementation of the present application, but the protection scope of the present application is not limited to this, and the skilled in the art should understand that any change or replacement which can be easily thought by the skilled in the art within the technical range disclosed by the present application falls within the protection scope and the disclosed range of the present application.

Claims

1. A ternary supported catalyst, characterized in that, The ternary supported catalyst includes a support and an additive supported on the surface of the support. The support includes In2O3 and an oxide containing M. The oxide containing M includes any one or a combination of at least two of ZrO2, Ga2O3 or ZnO. The additive includes Rh, Pd and Cu elements. In the ternary supported catalyst, the content of Rh element is 1-10wt%, the content of Pd element is 0.1-5wt%, and the content of Cu element is 0.8-10wt%.

2. The ternary supported catalyst according to claim 1, characterized in that, In the ternary supported catalyst, the In2O3 content is 1-15 wt%, preferably 10-15 wt%; Preferably, the content of the oxide containing M in the ternary supported catalyst is 60-97.6 wt%, more preferably 60-86 wt%.

3. The ternary supported catalyst according to claim 1 or 2, characterized in that, The ternary supported catalyst includes a support, a first supported layer supported on the surface of the support, a second supported layer on the surface of the first supported layer, and a third supported layer on the surface of the second supported layer. The first supported layer includes Rh element, the second supported layer includes Pd element, and the third supported layer includes Cu element.

4. A method for preparing a ternary supported catalyst as described in any one of claims 1-3, characterized in that, The preparation method includes the following steps: According to the formulation, the support, Rh source, Pd source, Cu source and solvent are mixed, allowed to stand, dried and calcined to obtain the ternary supported catalyst.

5. The preparation method according to claim 4, characterized in that, The steps of mixing, settling, drying, and calcining the support, Rh source, Pd source, Cu source, and solvent include: The carrier, Rh source, and solvent are first mixed, allowed to stand, dried, and calcined once to obtain the Rh-loaded carrier. The Rh-loaded support, Pd source, and solvent were then subjected to a second mixing, a second settling, a second drying, and a second calcination to obtain the Rh and Pd-loaded support. The ternary supported catalyst is obtained by mixing the Rh and Pd supported carrier, Cu source and solvent three times, allowing them to stand three times, drying three times and calcining three times.

6. The preparation method according to claim 5, characterized in that, The time for the first settling, second settling, and third settling is independently 1-4 hours; Preferably, the temperatures for the first mixing, second mixing, and third mixing are each independently 70-90℃, the stirring rates are each independently 200-400rpm, and the times are each independently 2-4h. Preferably, the temperature for the first drying step is 80-150℃, and the time is 8-15 hours. Preferably, the temperature of the first roasting is 300-500℃ and the time is 3-8 hours; Preferably, the secondary drying temperature is 80-120℃ and the time is 6-13 hours; Preferably, the secondary calcination temperature is 240-450℃ and the time is 2-6 hours; Preferably, the temperature for the three drying processes is 60-110℃, and the time is 8-15 hours. Preferably, the temperature of the three calcinations is 200-400℃ and the time is 2-6 hours.

7. The preparation method according to any one of claims 4-6, characterized in that, The method for preparing the carrier includes the following steps: A mixed metal salt solution and a precipitant are mixed, and a precipitation reaction and aging are carried out to obtain a reaction product. The reaction product is then washed, dried, and sintered to obtain the carrier. The mixed metal salt solution includes In ions and M ions, wherein the M ions include any one or a combination of at least two of Zr ions, Ga ions, or Zn ions.

8. The preparation method according to claim 7, characterized in that, The endpoint pH of the precipitation reaction is 8.5-10.5; Preferably, the precipitation reaction is carried out at a temperature of 60-80°C; Preferably, the aging time is 1.5-3 hours; Preferably, the sintering heating rate is 1-5℃ / min, the temperature is 300-600℃, and the holding time is 2-5h.

9. The preparation method according to claim 7 or 8, characterized in that, The precipitant includes any one or a combination of at least two of sodium carbonate solution, ammonium carbonate solution, ammonium acetate solution or sodium hydroxide solution; Preferably, the washing solution used in the washing process includes deionized water; Preferably, the drying temperature is 80-110℃ and the drying time is 6-12h.

10. An application of the ternary supported catalyst as described in any one of claims 1-3, characterized in that, The applications include the synthesis of methanol from CO2 hydrogenation.

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