Hydrogenated TiO2 supported Ru for selective methanation of CO in practical conditions

• Published in: Applied catalysis. B, Environmental Environmental, 2021-12, Vol.298, p.120597, Article 120597
• Main Authors: Li, Xiaoyu, Han, Yujia, Huang, Yike, Lin, Jian, Pan, Xiaoli, Zhao, Ziang, Zhou, Yanliang, Wang, Hua, Yang, Xiaofeng, Wang, Aiqin, Li, Lin, Qiao, Botao, Wang, Xiaodong
• Format: Article
• Language: English
• Subjects: Carbon dioxide; Carbon monoxide; Catalyst characterization; Catalysts; CO selective methanation; Defects; Hydrogenated TiO2; Hydrogenation; Metal surfaces; Methanation; Ru/TiO2; Selectivity; Spectroscopy; Titanium dioxide
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2021.120597

[Display omitted] •H-TiO2 supported Ru catalyst exhibits high activity, selectivity, and stability for CO selective methanation in practical conditions.•The lowered Ru valance on H-TiO2 improves CO adsorption and activation, and meanwhile inhibits CO2 hydrogenation at metal-support interface.•Using H-TiO2 as support is general to promote CO methanation. Selective methanation of CO (SMET) is promising for deep removal of low-concentration CO in excess H2. However, the development of suitable catalysts applied in practical conditions remains a great challenge. Here we report a general strategy to develop highly efficient SMET catalysts by using hydrogenated TiO2 (H-TiO2) as support. The H-TiO2 supported Ru catalysts can remove CO to below 10 ppm with greater than 50 % selectivity in a wide temperature range of 200−265 °C, with a good long-term stability. Detailed characterizations including operando spectroscopy and in-situ XPS combined with DFT calculation revealed that the lowered Ru valance on H-TiO2 strengthens CO adsorption on both metal surface and metal-support interface which improved CO activation and inhibited CO2 hydrogenation, respectively, leading to enhancement of both activity and selectivity.