CN-122006768-A - La2O2CO3Preparation of Pt/La by supporting Pt nanoparticles2O2CO3Method for preparing nano catalyst and catalyst application

Abstract

The invention discloses a method for preparing a Pt/La 2 O 2 CO 3 nano catalyst by La 2 O 2 CO 3 loaded Pt nano particles and application of the catalyst, and relates to the technical field of nano catalyst preparation, wherein the preparation method comprises the steps of synthesizing La 2 O 2 CO 3 single carrier La 2 O 2 CO 3 -S or La 2 O 2 CO 3 -M mixed carrier La 2 O 3 and La 2 O 2 CO 3 ; preparing Pt colloid, preparing Pt/La 2 O 2 CO 3 -S catalyst or Pt/La 2 O 2 CO 3 -M catalyst with different Pt loading by adopting a colloid deposition method, and preparing the Pt/La 2 O 2 CO 3 -S catalyst and the Pt/La 2 O 2 CO 3 -M catalyst which are used for catalyzing CO 2 hydrogenation to prepare CO. The invention has the beneficial effects that the preparation flow of the catalyst is simple and convenient, the Pt/La 2 O 2 CO 3 -S catalyst and the Pt/La 2 O 2 CO 3 -M catalyst have higher catalyst activity, selectivity and stability, and the problems of lower activity and stability of the Pt-based catalyst at high temperature in the CO hydrogenation preparation reaction of catalytic CO 2 are solved.

Inventors

• ZHANG PENG
• LIU GUANGHUI
• KANG YUHONG
• WEN YAOSHUN
• Yin Yangfan
• SHI CHEN
• ZHANG XINGLONG
• ZHU YANAN
• GAO YONG

Assignees

• 陕西榆林能源集团有限公司
• 榆林学院

Dates

Publication Date

20260512

Application Date

20251212

Claims (5)

1. The method for preparing the Pt/La 2 O 2 CO 3 nano catalyst by using the La 2 O 2 CO 3 loaded Pt nano particles is characterized by comprising the following steps of: a. synthesis of La 2 O 2 CO 3 Single vector La 2 O 2 CO 3 -S Adding 1 g La (NO 3 ) 3 •6H 2 O into 60 mL deionized water, continuously stirring, adjusting the pH to 12 with NaOH, continuously stirring for 1 h, transferring into a 100 mL hydrothermal synthesis kettle, heating for 16 h at 100-120 ℃, reducing the temperature to room temperature, filtering by using a Buchner funnel to obtain white precipitate, washing with deionized water, drying for 10 h at 60-80 ℃, grinding to obtain white powder, and finally calcining the white powder in a muffle furnace for 4h at 400-600 ℃ to obtain a La 2 O 2 CO 3 single carrier, namely La 2 O 2 CO 3 -S; b. Preparation of Pt colloid Sequentially adding 0.05-0.10 g PtCl 4 , 0.08-0.12 g NaOH and 20-40 mL ethylene glycol into a 150 mL round bottom flask, stirring at room temperature to uniformly mix, then keeping stirring, and carrying out reflux heating in an oil bath at 180-200 ℃ for 2-4h to obtain black Pt colloid; c. preparation of Pt/La 2 O 2 CO 3 -S catalysts with different Pt loadings by adopting colloid deposition method 0.5 GLa 2 O 2 CO 3 -S is dispersed in 25mL of deionized water, uniformly dispersed by stirring and ultrasonic method, then a certain amount of Pt colloid is dripped at normal temperature, stirring is continued for 24: 24h, and then the Pt/La 2 O 2 CO 3 -S catalyst is obtained by centrifugation and washing with deionized water, and drying 10: 10h at 80 ℃.
2. 2. The method for preparing a Pt/La 2 O 2 CO 3 nano-catalyst by using La 2 O 2 CO 3 -supported Pt nano-particles according to claim 1, further comprising the preparation of a Pt/La 2 O 2 CO 3 -M catalyst, comprising the following steps: (1) Process of synthesizing La 2 O 3 and La 2 O 2 CO 3 mixed vector La 2 O 2 CO 3 -M: Adding 1 g La (NO 3 ) 3 •6H 2 O into 60 mL deionized water, continuously stirring, adjusting the pH to 12 with NaOH, continuously stirring for 1h, transferring into a 100 mL hydrothermal synthesis kettle, heating for 8 hours at 100-120 ℃, reducing the temperature to room temperature, filtering by using a Buchner funnel to obtain white precipitate, washing with deionized water, drying at 60-80 ℃ for 10 h, grinding to obtain white powder, and finally calcining the white powder in a muffle furnace at 400-600 ℃ for 4 h to obtain a La 2 O 3 and La 2 O 2 CO 3 mixed carrier, namely La 2 O 2 CO 3 -M; (2) Preparation of Pt colloid Sequentially adding 0.05-0.10 g PtCl 4 , 0.08-0.12 g NaOH and 20-40 mL ethylene glycol into a 150 mL round bottom flask, stirring at room temperature to uniformly mix, then keeping stirring, and carrying out reflux heating in an oil bath at 180-200 ℃ for 2-4h to obtain black Pt colloid; (3) Preparation of Pt/La 2 O 2 CO 3 -M catalysts with different Pt loadings by adopting colloid deposition method 0.5 GLa 2 O 2 CO 3 -M was dispersed in 25mL of deionized water, uniformly dispersed by stirring and ultrasonic method, then a certain amount of Pt colloid was dropped at normal temperature and kept 24: 24h with continuous stirring, then the Pt/La 2 O 2 CO 3 -M catalyst was obtained by centrifugation and washing with deionized water and then drying 10: 10h at 80 ℃.
3. 3. The method for preparing the Pt/La 2 O 2 CO 3 nano-catalyst by using the La 2 O 2 CO 3 loaded Pt nano-particles according to claim 1 or 2, wherein the concentration of NaOH is 0.5 mol.L −1 .
4. 4. The method of preparing a Pt/La 2 O 2 CO 3 nano-catalyst with La 2 O 2 CO 3 supported Pt nano-particles according to claim 1 or 2, wherein Pt loading is 0.1%, 0.2% and 0.5%.
5. 5. Use of a Pt/La 2 O 2 CO 3 nm catalyst prepared according to the method of claim 1 or 2 for catalyzing the hydrogenation of CO 2 to produce CO.

Description

Method for preparing Pt/La 2O2CO3 nano-catalyst by using La 2O2CO3 loaded Pt nano-particles and catalyst application Technical Field The invention relates to the technical field of nano-catalyst preparation, in particular to a method for preparing a Pt/La 2O2CO3 nano-catalyst by using La 2O2CO3 loaded Pt nano-particles and application of the catalyst. Background Under the driving of global energy structure transformation and a double-carbon target, the recycling utilization of carbon dioxide (CO 2) becomes a key break. The reverse water gas shift reaction (RWGS: CO 2 + H2 → CO + H2 O) is a core technology for converting CO 2 into high value-added synthesis gas (CO/H 2), and has important strategic values in the fields of chemical industry, metallurgy and hydrogen energy. However, the high energy consumption of the reaction (the endothermic reaction requires 500-800 ℃) and the high cost and easy deactivation of the noble metal catalyst seriously restrict the industrial application thereof. The platinum (Pt) based catalyst becomes a research hot spot of RWGS reaction due to excellent hydrogenation activity and sintering resistance, but the problems of insufficient stability, low CO 2 activation efficiency and the like in a high-temperature oxidation environment are needed to be solved. La 2O2CO3 is used as a novel catalyst carrier, has obvious advantages in reactions such as Reverse Water Gas Shift (RWGS) and the like, and has the characteristics that (1) compared with the traditional oxide carrier (such as CeO 2、Al2O3), the La 2O2CO3 has the characteristics that (1) a unique layered structure and oxygen vacancy enrichment ‌ are formed by alternating La 2O22 + and CO 32 -layers, and the interlayer oxygen vacancy concentration is obviously higher than that of the traditional oxide. This structure not only enhances the chemisorption of CO 2, but also promotes heterolytic dissociation of H 2, forming a hindered Lewis acid base pair (FLP), thereby accelerating the RWGS reaction rate. In contrast, ceO 2 has oxygen vacancies, but is susceptible to structural reconstruction at high temperatures, resulting in deactivation of the active site. (2) The strong alkaline surface of La 2O2CO3 can stabilize carbonate intermediate, reduce by-product generation, and meanwhile, the layered structure can still keep stability in high-temperature oxidation environment, thereby effectively inhibiting migration and agglomeration of Pt nano particles. Conventional Al 2O3 supports are prone to sintering at high temperatures and the surface acidity may lead to catalyst poisoning. (3) The synergistic catalytic effect and industrial suitability that ‌ Pt-loaded La 2O2CO3 can realize high CO selectivity, and the oxygen storage capacity and the carrier alkalinity synergistically optimize the reaction path, so that the catalyst is suitable for industrial H 2/CO2 proportion conditions. While the composite carrier such as Y 2O3/Al2O3 can promote CO 2 adsorption, a complex modification process is needed, and the cost is high. Therefore, la 2O2CO3 solves the bottleneck of the traditional carrier in the aspects of stability, activity and cost through structural innovation, and provides a new idea for efficient CO 2 conversion. Disclosure of Invention The invention discloses a method for preparing a Pt/La 2O2CO3 nano catalyst by La 2O2CO3 loaded Pt nano particles and application of the catalyst, wherein the preparation flow of the catalyst is simple, the catalyst activity, selectivity and stability are high, and the problems of low activity and stability of a Pt-based catalyst at high temperature in the process of preparing CO by catalyzing CO 2 hydrogenation are solved. In order to achieve the above purpose, the present invention adopts the following technical scheme: A method for preparing a Pt/La 2O2CO3 nano catalyst by La 2O2CO3 loaded Pt nano particles comprises the following steps of: a. synthesis of La 2O2CO3 Single vector La 2O2CO3 -S Adding 1 g La (NO 3)3•6H2 O into 60 mL deionized water, continuously stirring, adjusting the pH to 12 with NaOH, continuously stirring for 1 h, transferring into a 100 mL hydrothermal synthesis kettle, heating for 16 h at 100-120 ℃, reducing the temperature to room temperature, filtering by using a Buchner funnel to obtain white precipitate, washing with deionized water, drying for 10 h at 60-80 ℃, grinding to obtain white powder, and finally calcining the white powder in a muffle furnace for 4h at 400-600 ℃ to obtain a La 2O2CO3 single carrier, namely La 2O2CO3 -S; b. Preparation of Pt colloid Sequentially adding 0.05-0.10 g PtCl 4, 0.08-0.12 g NaOH and 20-40 mL ethylene glycol into a 150 mL round bottom flask, stirring at room temperature to uniformly mix, then keeping stirring, and carrying out reflux heating in an oil bath at 180-200 ℃ for 2-4h to obtain black Pt colloid; c. preparation of Pt/La 2O2CO3 -S catalysts with different Pt loadings by adopting colloid deposition method 0.5 GLa 2O2CO3 -S