Graphitic carbon nitride catalyzes selective oxidative dehydrogenation of propane
writer:Lei Cao,Pengcheng Dai*,Lei Zhu*,Liting Yan,Ruihua Chen,Dandan Liu, Xin Gu, Qingzhong Xue,Xuebo Zhao*
keywords:Graphitic carbon nitride;Carbonyl groups;Oxidative dehydrogenation;Heterogeneous catalysis;Light olefins
source:期刊
specific source:Applied Catalysis B: Environmental,2020,262, 11827
Issue time:2020年
Exothermic oxidative dehydrogenation of propane (ODHP) to olefins is a promising alternative to industrialized direct dehydrogenation. However, it encounters a great challenge to control the olefin selectivity as the overoxidation to produce carbon oxides (COx) is thermodynamically more favorable. In this work, graphitic carbon nitride was reported to be a new kind of metal-free catalyst for ODHP, obtaining high selectivity for propylene (74.7%) and ethylene (14.9%) at a given propane conversion of 12.8%. Based on the spectroscopic insights and in situ experiments, the carbonyl groups modified on the graphitic carbon nitride were affirmed as active sites. A feasible ODHP reaction pathway was hypothesized by density functional theory (DFT) in which two adjacent carbonyl groups on the edge of carbon nitride can activate two C-H bonds of propane simultaneously, thus avoiding the generation of free C3H7* radicals and leading to the high selectivity of light olefins.