Non-oxidative propane dehydrogenation over Co/Ti-ZSM-5 catalysts: Ti species-tuned Co state and surface acidity

• Published in: Microporous and mesoporous materials Vol. 341; p. 112115
• Main Authors: Wu, Yueqi, Long, Jiangping, Wei, Sheng, Gao, Yating, Yang, Dan, Dai, Yihu, Yang, Yanhui
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.08.2022
• Subjects: Acidity; Co catalyst; Coke; Propane dehydrogenation; Propylene; Ti-ZSM-5 zeolite; Propylene; Co catalyst; Ti-ZSM-5 zeolite; Acidity; Propane dehydrogenation; Coke
• ISSN: 1387-1811; 1873-3093
• DOI: 10.1016/j.micromeso.2022.112115

With the modified Ti-ZSM-5 zeolites as supports, the propane dehydrogenation (PDH) performance of the non-noble metal Co-based catalysts can be enhanced, which is benefited from the Ti species-tuned state of active Co species and surface acid property. The developed Co/Ti-ZSM-5 catalysts exhibit >95% C3H6 selectivity and good regeneration stability in the recycling PDH reactions. The characterization results illustrate the structural evolution of Ti from the framework and extra-framework Ti species to the small-size anatase TiO2 species with decreasing the Si/Ti ratio of the Ti-ZSM-5 zeolites, tailoring the dispersion and chemical state of the Co sites at different Co-zeolite or Co-TiO2 interfaces. The Ti-ZSM-5 zeolites with high Si/Ti ratios also show significantly reduced surface acidity especially the Brønsted acidity in comparison with the Al-ZSM-5 zeolite, thus facilitating the C3H6 desorption for enhancing the selectivity and anti-coke stability. [Display omitted] •Ti–ZSM–5 zeolite–supported Co nanoparticle catalyst selectively catalyze propane dehydrogenation.•Ti/Si ratios determine the location and chemical state of the Ti species in the Ti–ZSM–5 supports.•Ti/Si ratios tune the dispersion and chemical state of Co species and surface acid property.•Suppressing C3H8 C–C cracking and facilitating C3H6 desorption lead to high selectivity and anti–coke stability.