The highly selective catalytic hydrogenation of CO_(2)to CO over transition metal nitrides

查看全文 作　　者：Yichao [1]Wu;Zhiwei [1]Xie;Xiaofeng [2]Gao;Xian [2]Zhou;Yangzhi [1]Xu;Shurui [1]Fan;Siyu [2]Yao;Xiaonian [1]Li;Lili [1]Lin 机构地区：[1]Institute of Industrial Catalysis,State Key Laboratory of Green Chemistry Synthesis Technology,College of Chemical Engineering,Zhejiang University of Technology,Hangzhou 310014,China;[2]Key Laboratory of Biomass Chemical Engineering of Ministry of Education,College of Chemical and Biological Engineering,Zhejiang University,Hangzhou 310027,China 出　　处：《Chinese Journal of Chemical Engineering》索引2022年第35卷第3期,共7页 基　　金：financially supported by the National Natural Science Foundation of China(22002140);Zhejiang Provincial Natural Science Foundation of China(LR21B030001 and LR22b030003);Young Elite Scientist Sponsorship Program by CAST(No.2019QNRC001);Use of the Advanced Photon Source(beamlines 17-BM,for in-situ XRD characterization)was supported by the U.S.DOE under contract no.DE-AC02-06CH11357。 摘　　要：Three transition metal-like facet centered cubic structured transition metal nitrides,γ-Mo_(2)N,β-W_(2)N andδ-NbN,are synthesized and applied in the reaction of CO_(2)hydrogenation to CO.Among the three nitride catalysts,theγ-Mo_(2)N exhibits superior activity to target product CO,which is 4.6 and 76 times higher than the other two counterparts ofβ-W_(2)N andδ-NbN at 600℃,respectively.Additionally,γ-Mo_(2)N exhibits excellent stability on both cyclic heating-cooling and high space velocity steady state operation.The deactivation degree of cyclic heating-cooling evaluation after 5 cycles and long-term stability performance at 773 and 873 K in 50 h are all less than 10%.In-situ XRD and kinetic studies suggest that theγ-Mo_(2)N itself is able to activate both of the reactants CO_(2)and H_(2).Below 400℃,the reaction mainly occurs at the surface ofγ-Mo_(2)N catalyst.CO_(2)and H_(2)competitively adsorbe on the surface of catalyst and CO_(2)is the relatively stronger surface adsorbate.At a higher temperature,the interstitial vacancies of theγ-Mo_(2)N can be reversibly filled with the oxygen from CO_(2)dissociation.Both of the surface and bulk phase sites ofγ-Mo_(2)N participate in the high temperature CO_(2)hydrogenation pathway. 关 键 词：Carbon dioxide Chemical reaction CATALYSIS Reverse water gas shift(RWGS)reaction Transition metal nitride In-situ X-ray diffraction characterization