Exploring the influence of nickel precursors on constructing efficient Ni-based CO2 methanation catalysts assisted with in-situ technologies

• Published in: Applied catalysis. B, Environmental Environmental, 2021-11, Vol.297, p.120486, Article 120486
• Main Authors: Wen, Xueying, Xu, Leilei, Chen, Mindong, Shi, Yiyu, Lv, Chufei, Cui, Yan, Wu, Xianyun, Cheng, Ge, Wu, Cai-e, Miao, Zhichao, Wang, Fagen, Hu, Xun
• Format: Article
• Language: English
• Subjects: Carbon dioxide; Catalysts; CO2 methanation; Deactivation; Fourier transforms; In-situ DRIFTS; Intermediates; Mass spectrometry; Mass spectroscopy; Methanation; Nickel; Nickel chloride; Nickel salt precursors; Nickel sulfate; Nickel sulfide; Online-tandem TG-MS; Precursors; Reaction intermediates
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2021.120486

[Display omitted] •A series of Ni/SiO2 catalysts were prepared with different nickel salt precursors.•The intermediates of calcination process studied by in-situ DRIFTS and online TG-MS.•The catalyst with nickel acetylacetonate precursor performed the highest activity.•The precursor influenced the Ni dispersion and strength of metal-support interaction.•The precursor determined the reaction pathway and apparent activation energy. In this work, a series of Ni-based CO2 methanation catalysts were prepared with different nickel salt precursors. The Ni-AA catalyst with nickel acetylacetonate precursor displayed the highest activity among these catalysts. The in-situ diffused reflectance infrared Fourier transform spectroscopy (in-situ DRIFTS) and the online-tandem thermogravimetric mass spectrometry (TG-MS) were performed to investigate the intermediates of the catalyst calcination process. The superior performance of the Ni-AA catalyst could be derived from its special coordinating anion. Furthermore, the rapid deactivation of the Ni-S catalyst with nickel sulfate precursor was attributed to the generation of the Ni3S2 after reduction pretreatment. As for the Ni-Cl catalyst with nickel chloride precursor, its negligible activity could be owing to poisoning effect of the Cl− by the coverage of the catalyst surface. Therefore, the significant role of the metal salt precursor should be preferentially considered when designing the Ni-based catalysts and even other metal based heterogeneous catalysts.