CN-117654565-B - Supported noble metal catalyst for reverse water gas shift reaction and preparation method and application thereof

CN117654565BCN 117654565 BCN117654565 BCN 117654565BCN-117654565-B

Abstract

The invention provides a supported noble metal catalyst for reverse water gas shift reaction, which comprises a zirconium carbide carrier and active components uniformly supported on the carrier, wherein the active components comprise noble metal elements such as Pt, rh, au, ru, pd, ir. The invention also provides a preparation method of the supported noble metal catalyst, which comprises the steps of preparing impregnating solution of active components, adding the impregnating solution into a carrier for mixing, removing a solvent from the mixed solution to obtain a solid product, and grinding to obtain the supported noble metal catalyst. The supported noble metal catalyst provided by the invention has a wide active temperature window (the active temperature interval is 250-500 ℃), a high CO 2 conversion rate (33% -42%) and a high CO selectivity (80% -100%) in the reverse water gas shift reaction, and has the advantages of simple preparation method, obvious catalytic effect, suitability for the conversion treatment of CO 2 in industry and wide popularization and application prospect.

Inventors

DING SHIPENG
DONG HONGSEN
ZHANG YAPING
SHEN KAI

Assignees

东南大学

Dates

Publication Date: 20260505
Application Date: 20231124

Claims (7)

1. The application of the supported noble metal catalyst in the reverse water gas shift reaction is characterized in that the supported noble metal catalyst comprises a carrier and active components uniformly supported on the carrier, wherein the carrier is zirconium carbide, the active components are selected from Pt or Rh, and the loading amount of the active components on the carrier is 0.1-2.0 wt.%; The reverse water gas shift reaction condition comprises that the reaction gas is mixed gas formed by H 2 and CO 2 according to a molar ratio of 3:1, the volume space velocity of the reactor is 12000-60000H -1 , the reaction temperature is 250-500 ℃, and the reaction pressure is 0.1-1 MPa.
2. The use according to claim 1, wherein the preparation method of the supported noble metal catalyst comprises the following steps: s1, preparing an impregnating solution of an active component; S2, adding the impregnating solution into a carrier, and fully mixing to obtain a mixed solution; S3, removing the solvent from the mixed solution to obtain a solid product, and grinding to obtain the supported noble metal catalyst for the reverse water gas shift reaction.
3. The application of the method according to claim 2, wherein in the step S1, the preparation method of the impregnation liquid of the active component comprises the steps of dispersing salt or acid of the active component in a solvent to obtain the impregnation liquid with the concentration of the active component of 1-10 mg/mL.
4. The use according to claim 3, wherein the salt or acid of the active ingredient comprises one of the nitrate, chloride, organic salt of the active metal.
5. The use according to claim 2, wherein in step S2 the mixing is performed at a temperature of 20-30 ℃ for a time of 6-24 hours.
6. The use according to claim 2, wherein in step S3, the solvent removal means comprises one of freeze-drying or rotary evaporation drying.
7. The method according to claim 1, wherein the supported noble metal catalyst is subjected to reduction activation, and the reduced and activated supported noble metal catalyst is applied to a fixed bed reactor for reverse water gas shift reaction.

Description

Supported noble metal catalyst for reverse water gas shift reaction and preparation method and application thereof Technical Field The invention belongs to the technical field of catalysts, and particularly relates to a supported noble metal catalyst and a preparation method thereof, and application of the supported noble metal catalyst in reverse water gas shift reaction. Background The consumption of a large amount of fossil energy causes excessive CO 2 emission, causes serious environmental problems such as climate change, global warming, sea level rising and the like, and brings serious threat to daily life of human beings. Meanwhile, CO 2 is the most abundant and cheapest C1 resource in the global reserves, and has huge development and utilization potential. Therefore, improving the efficiency of capturing, storing and recycling CO 2 is an important direction of current research on CO 2. Among the numerous CO 2 treatments, the preparation of CO by hydrogenation of CO 2 by reverse water gas shift reaction (CO 2+H2＝CO+H2 O) is a promising research direction. CO is not only one of important raw materials for industrial Fischer-Tropsch synthesis, but also can be further hydrogenated and converted into high-added-value chemicals such as olefin, aromatic hydrocarbon and the like, and has wide application prospect in spark detection. The current industrial application of the reverse water gas shift reaction has the obstacle of overcoming the defects that the energy consumption of C=O bond is higher, CH 4 and other byproducts are generated in the reaction, and the deactivation behaviors such as agglomeration, oxidation, carbon deposition and the like are easy to occur under the high-temperature condition of the existing catalyst, so that the catalytic efficiency is reduced. Therefore, the key to the current research is to develop efficient, highly selective, highly stable catalysts. Reverse water gas shift reaction catalysts can be mainly classified into three types, namely, supported catalysts, oxide catalysts and carbide catalysts. The supported catalyst has the dual functions of synergistically activating CO 2 and dissociating H 2, and is the most widely studied and commonly used catalyst in RWGS reactions. The supported catalyst comprises a noble metal catalyst and a non-noble metal catalyst, and the noble metal catalyst has good catalytic performance and high efficiency and shows extremely high catalytic activity on reverse water gas shift reaction. However, a part of supported noble metal catalysts (such as platinum-based catalysts, rhodium-based catalysts, etc.) cannot always have both higher CO 2 conversion rate and higher CO selectivity (especially at higher reaction temperatures), which is also a problem to be solved in the current research of supported noble metal catalysts. Common carrier materials for the supported platinum-based catalyst include Al 2O3、CeO2、TiO2、Fe2O3, KLTL molecular sieves, mullite and the like. Yang et al report a catalyst using L-type zeolite as a carrier and Pt as an active component, wherein the CO selectivity of the catalyst can reach 100% at 400 ℃, but the CO 2 conversion rate is only about 5%, chinese patent CN106881084A discloses a supported platinum-based catalyst using mullite as a carrier, pt as an active component, an additive is any one or more than two of oxides of X (Li, na, K, rb, cs), the highest CO 2 conversion rate of the catalyst can reach 35%, but the CO selectivity is reduced at high temperature, chinese patent CN108144637A discloses a supported platinum-based catalyst using KLTL molecular sieve as a carrier and Pt as an active component and introducing alkali metal M (Li, na, K, cs) as an additive, and the highest CO 2 conversion rate and nearly 100% CO selectivity of the catalyst can reach 27%, but the preparation method is more complex. Common support materials for supported rhodium-based catalysts include TiO 2、Al2O3、SiO2, zeolites, srTiO 3、CeO2, and the like. Buche et Al explored the reverse water gas shift reactivity of Rh/Al 2O3 under H 2:CO2 =4:1 conditions. The results show that at 400 ℃, the CO 2 conversion of the catalyst reached 60%, but the CO selectivity was only about 1%. Loading Rh on ZrO 2 by Li et al prepared the single-atom catalyst Rh 1/ZrO2 and studied its reactivity, which was found to have a CO 2 conversion of 62% at 440 ℃, but also a CO selectivity of only 1%. Based on the above, a brand new supported noble metal catalyst for the reverse water gas shift reaction is provided, so that the higher CO 2 conversion rate and higher CO selectivity are simultaneously shown in the reverse water gas shift reaction process, and the technical problem to be solved is needed. Disclosure of Invention One of the purposes of the present invention is to provide a supported noble metal catalyst which exhibits both a higher CO 2 conversion and a higher CO selectivity in the reverse water gas shift reaction. The second purpose of the invention is to provi