Yang Tianxing, Zhong Yuan, Li Jiale, Ma Rui, Yan Hong, Liu Yanan, He Yufei, Li Dianqing
State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
Beijing Engineering Center for Hierarchical Catalysts, Beijing University of Chemical Technology, Beijing 100029, China.
ACS Appl Mater Interfaces. 2021 Jul 21;13(28):33045-33055. doi: 10.1021/acsami.1c07842. Epub 2021 Jul 7.
It is an important task to develop low-cost and anticoking catalysts for the propane dehydrogenation (PDH) reaction. In this work, the P element is introduced to the Ru-based catalyst to obtain Ru sites with a unique structure and the obtained RuP (x/y = 2:1, 1:1, 1:2) catalysts are then employed in PDH. Density functional theory (DFT) results show that the addition of P leads to the formation of separated Ru sites and the adjustment of the valance band state of Ru. The upward shift of the d-band center leads to a reduction of the reaction energy barrier for dehydrogenation of propane and an enhancement of catalytic activity. The analysis of the competition between propylene deep dehydrogenation and propylene desorption for each catalyst shows that desorption of propylene is preferred on the RuP(112) surface. Considering both catalytic activity and propylene selectivity, the RuP catalyst is potential for the propane dehydrogenation reaction. On the RuP surface, the PDH reaction proceeds by the dehydrogenation of the H atom on the methylene group (isopropyl pathway), thus restraining the deep dehydrogenation of propylene. The RuP catalysts are also synthesized in experiments, and PDH evaluation shows that the RuP structure is a remarkable PDH catalyst with a stable structure, anticoking ability, and low cost.
开发用于丙烷脱氢（PDH）反应的低成本且抗结焦催化剂是一项重要任务。在本工作中，将P元素引入到Ru基催化剂中以获得具有独特结构的Ru位点，然后将所制备的RuP（x/y = 2:1、1:1、1:2）催化剂用于PDH反应。密度泛函理论（DFT）结果表明，P的添加导致形成分离的Ru位点并调整了Ru的价带状态。d带中心的上移导致丙烷脱氢反应能垒降低以及催化活性增强。对每种催化剂上丙烯深度脱氢与丙烯脱附之间竞争关系的分析表明，在RuP(112)表面上丙烯脱附占优。综合考虑催化活性和丙烯选择性，RuP催化剂在丙烷脱氢反应中具有潜力。在RuP表面上，PDH反应通过亚甲基上H原子的脱氢进行（异丙基途径），从而抑制了丙烯的深度脱氢。实验中还合成了RuP催化剂，PDH评价表明RuP结构是一种具有稳定结构、抗结焦能力且成本低的优异PDH催化剂。
