In situ redispersion of rhodium nanocatalyst for CO2 reforming of CH4

• Published in: Journal of environmental chemical engineering 2021-08, Vol.9 (4), p.105790, Article 105790
• Main Authors: Fu, Yu, Kong, Wenbo, Pan, Bingrong, Yuan, Changkun, Li, Shuqing, Zhu, He, Zhang, Jun
• Format: Article
• Language: English
• Subjects: Deactivation; Heat treatment; Hydrocarbons; Noble metals; Titania
• ISSN: 2213-3437; 2213-3437
• DOI: 10.1016/j.jece.2021.105790

Noble metal nanoparticles (NPs) exhibit high reactivity towards hydrocarbon reforming, however, suffer from agglomeration and poisoning issues (e.g., carbon deposition). A facile and environmental approach to rejuvenate noble metal catalysts is techniques using thermal redox cycles. Here we demonstrate that in situ thermal oxidative aging and reduction strategy can reverse the sintering of Rh/TiO2 catalyst and meanwhile this redox process significantly affects the catalytic performance towards methane dry reforming (DRM). The oxidative aging process has substantial impact on the mobilization of Rh species across TiO2, and thus the degree of oxymetal activation and the Rh NPs size. In the subsequent reductive process, reduction temperature not only influences oxymetal activation but also the electronic structure of Rh NPs, which directly relates to the carbon formation. [Display omitted] •Redispersion of the Rh/TiO2 catalyst is accomplished by thermal aging strategy.•The rejuvenated Rh/TiO2 catalyst exhibits good performance toward DRM reaction.•The oxidative process dramatically affects the degree of oxymetal activation, Rh particle size and carbon formation.•Metal-support interaction makes dual effects on the performance of the Rh/TiO2 catalyst.•The mutual influence of redox process on redispersing Rh/TiO2 for DRM is elucidated.