Study on the reaction mechanism of SO 2 hydrogenation over Mo‐based catalyst

• Published in: AIChE journal Vol. 69; no. 7
• Main Authors: Su, Ran, Wang, Xiaosheng, Li, Ranjia, Yu, Changchun, Zhou, Hongjun, Liu, Aihua, Liu, Jianli
• Format: Journal Article
• Language: English
• Published: 01.07.2023
• ISSN: 0001-1541; 1547-5905
• DOI: 10.1002/aic.18065

Abstract Mo‐based catalysts are widely used for the SO 2 hydrogenation process. However, the detailed reaction mechanism is still unclear and some details should be further supplemented. In this article, the SO 2 hydrogenation processes over the Mo‐based catalyst were systematically studied. Several technologies including temperature‐programmed experiments, isotope‐tracing experiment, fourier transform infrared spectroscopy, and switching experiment were adopted to investigate the reaction steps. The results indicated that during the SO 2 hydrogenation process there were three reaction processes containing six steps: First SO 2 would adsorb on the active sites, which could start at relatively low temperature. Then the adsorbed SO 2 would react with H 2 and gradually form elemental sulfur that could be strongly anchored with S atoms of the MoS 2 surface. Afterward, the sulfur further reacted with H 2 to generate H 2 S. Alongside with the consumption of S atoms, the sulfur would be reduced and the active sites was recovered, thus starting the next reaction cycle.