Preparation And Performance Study Of Metal Organic Framework And Zeolite Molecular Sieve Supported Nanoparticle Catalyst

CO2 is a greenhouse gas,but it is also a cheap carbon source stored in the atmosphere.Reducing CO2 through chemical reactions can decrease the amount of CO2 in the atmosphere,decline the occurrence of climate disasters,and generate high-value-added chemicals with reducing the current consumption of fossil energy.Based on this,the CO2 capture and storage has attracted extensive attention from researchers all over the world.It is a research hotspot for researchers recently to composite metal-organic frameworks or zeolite molecular sieves and nanoparticles to prepare catalysts.In this paper,the metal-organic framework and zeolite molecular sieve are used as the carrier,and the nanoparticles are used as the active ingredient.Through the rational design of the catalyst structure,the advantages of various materials are concentrated to prepare composite catalysts.The structure and morphology of the nanomaterials were characterized with SEM,TEM,EDS,BET,TGA and XRD instruments,and their ability to catalyze the hydrogenation of CO2 was systematically studied.1.PdNPs,Pd@PtNPs nanocubes and Pd@PtNCs nanocages were synthesised in advance and used to prepare the core-shell composite catalyst PdNPs@UiO-66,Pd@PtNPs@UiO-66 and hollow Pd@PtNCs@UiO-66 with metal nanoparticles as the core and UiO-66 as the shell.The core PdNPs and Pd@PtNPs have particle sizes of 19 nm and 21 nm,and Pd@PtNcs are nanocages with a thickness of only 2 nm.The effects of different reaction conditions on the formation of the core-shell structure were experimentally studied,and they were systematically characterized.The catalytic performance of the composite catalyst for CO2 hydrogenation was investigated.The results show that the catalyst with hollow nanocage structure has the least metal content and high atom utilization rate,but the best catalytic activity,and the highest CO2 conversion rate is 22.6%.2.Zeolite molecular sieves ZSM-5 and HZSM-5 with different silicon-to-aluminum ratios were synthesized and then were compounded with metal oxides ZnCrOx and ZnFeOx to prepare composite catalysts containing Lewis acid catalytic sites with continuous reaction series catalytic characteristics.Through the characterization of the morphology and structure of the catalytic material,it was found that this catalytic material is beneficial to increase the proportion of multi-carbon compounds in the CO2 hydrogenation catalytic product.