Enhanced CO
2 methanation at mild temperature on Ni/zeolite from kaolin: effect of metal-support interface.
RSC Adv 2021;
11:16376-16387. [PMID:
35479131 PMCID:
PMC9031409 DOI:
10.1039/d1ra01014j]
[Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Accepted: 04/26/2021] [Indexed: 11/25/2022] Open
Abstract
Catalytic CO2 hydrogenation to CH4 offers a viable route for CO2 conversion into carbon feedstock. The research aimed to enhance CO2 conversion at low temperature and to increase the stability of Ni catalysts using zeolite as a support. NaZSM-5 (MFI), NaA (LTA), NaY (FAU), and NaBEA (BEA) synthesized from kaolin were impregnated with 15% Ni nanoparticles in order to elucidate the effect of surface area, porosity and basicity of the zeolite in increasing Ni activity at mild temperature of ∼200 °C. A highly dispersed Ni catalyst was produced on high surface area NaY meanwhile the mesoporosity of ZSM-5 has no significant effect in improving Ni dispersion. However, the important role of zeolite mesoporosity was observed on the stability of the catalyst. Premature deactivation of Ni/NaA within 10 h was due to the relatively small micropore size that restricted the CO2 diffusion, meanwhile Ni/NaZSM-5 with a large mesopore size exhibited catalytic stability for 40 h of reaction. Zeolite NaY enhanced Ni activity at 200 °C to give 21% conversion with 100% CH4 selectivity. In situ FTIR analysis showed the formation of hydrogen carbonate species and formate intermediates at low temperatures on Ni/NaY, which implied the efficiency of electron transfer from the basic sites of NaY during CO2 reduction. The combination of Ni/NaY interfacial interaction and NaY surface basicity promoted CO2 methanation reaction at low temperature.
Different Na-zeolites as supports of Ni metal were successfully synthesized from kaolin-based material. Combination of interfacial interaction Ni-support and surface basicity promoted CO2 methanation reaction at a low temperature of ∼200 °C.![]()
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