摘要
在机械混合的MgO-Mg3(VO4)2,Mg3(VO4)2-Mg2V2O7和V2O5-MgV2O6双晶相催化剂体系上,研究了晶相间协同催化效应对环己烷氧化脱氢反应性能的影响.催化剂表征和反应结果表明,双晶相间协同效应或源于不同晶相间形成的内聚界面,或遵从溢流氧的遥控机理,或产生于其中一个晶相完全包覆整个催化剂表面.当在Mg3(VO4)2上进行环己烷氧化脱氢反应时,可加入适量MgO或Mg2V2O7以提高其催化性能.在80%Mg3(VO4)2-20%Mg2V2O7催化剂上,当环己烷转化率为15.5%时,环己烯选择性达44.9%.
The biphasic synergistic effect of a mechanically mixed Mg-V-O catalyst system,which included MgO-Mg3(VO4)2,Mg3(VO4)2-Mg2V2O7,and V2O5-MgV2O6 catalysts,in the oxidative dehydrogenation of cyclohexane was studied.Characterization results and catalytic performance measurements reveal that the biphasic synergistic effect derives from three mechanisms:the formation of coherent interface of the two phases,the remote control mechanism originated from the spillover of mobile surface oxygen,and the formation of a surface contamination layer of one phase on the surface of the catalyst.The biphasic synergistic effect on the conversion,yield,and selectivity was observed in Mg3(VO4)2 mixing with a suitable amount of MgO and Mg2V2O7.Among the catalyst system,the 80%Mg3(VO4)2-20%Mg2V2O7 catalyst exhibits better catalytic performance and shows cyclohexene selectivity of 44.9% with cyclohexane conversion of 15.5%.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
2010年第9期1177-1184,共8页
基金
化学工程联合国家重点实验室资助课题(SKL-ChE-08C03)
关键词
镁
钒
复合氧化物
环己烷
氧化脱氢
环己烯
magnesium
vanadium
complex oxide
cyclohexane
oxidative dehydrogenation
cyclohexene