Coupling acid catalysis and selective oxidation over MoO3-Fe2O3 for chemical looping oxidative dehydrogenation of propane
Xianhui Wang, Chunlei Pei, Zhi‐Jian Zhao, Sai Chen, Xinyu Li, Jiachen Sun, Hongbo Song, Guodong Sun, Wei Wang, Xin Chang, Xianhua Zhang, Jinlong Gong
Abstract
Abstract Redox catalysts play a vital role in chemical looping oxidative dehydrogenation processes, which have recently been considered to be a promising prospect for propylene production. This work describes the coupling of surface acid catalysis and selective oxidation from lattice oxygen over MoO 3 -Fe 2 O 3 redox catalysts for promoted propylene production. Atomically dispersed Mo species over γ-Fe 2 O 3 introduce effective acid sites for the promotion of propane conversion. In addition, Mo could also regulate the lattice oxygen activity, which makes the oxygen species from the reduction of γ-Fe 2 O 3 to Fe 3 O 4 contribute to selectively oxidative dehydrogenation instead of over-oxidation in pristine γ-Fe 2 O 3 . The enhanced surface acidity, coupled with proper lattice oxygen activity, leads to a higher surface reaction rate and moderate oxygen diffusion rate. Consequently, this coupling strategy achieves a robust performance with 49% of propane conversion and 90% of propylene selectivity for at least 300 redox cycles and ultimately demonstrates a potential design strategy for more advanced redox catalysts.