Highly selective hydrogenation of halonitroaromatics to aromatic haloamines by ligand modified Ni-based catalysts  

作　　者：Chun Shan Lu Jing Hui Lv Lei Ma Qun Feng Zhang Feng Feng Xiao Nian Li 

机构地区：[1]Industrial Catalysis Institute of Zhejiang University of Technology,State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology,Zhejiang University of Technology,Hangzhou 310032,China

出　　处：《Chinese Chemical Letters》2012年第5期545-548,共4页中国化学快报（英文版）

基　　金：the National Basic Research Program of China(973 Program)(No 2011CB710800);the National Natural Science Foundation of China(No20976164)

摘　　要：Ligand modification of Ni-based catalysts by coordination of dicyandiamide to Ni metal leads to enhanced selectivity for the selective hydrogenation of halonitroaromatics.The selectivity of above 99.9%to aromatic haloamines can be achieved at the conversion of 100%.The results of H_2-TPD and FT-IR experiments show that Ni^-H~＋ species possessing the properties of Lewis acid site on the surface of Raney Ni could be responsible for the hydrodehalogenation.When Raney Ni was treated by dicyandiamide,Ni^-H~＋ species interacted with N atom from the dicyandiamide.This interaction was stable even at reaction temperature,which reduced the possibility to form the intermediate state of Ar-Cl...H~＋Ni^-.And then C-Cl bond could not be polarized and activated.The hvdrodechlorination process was suppressed effectively.Ligand modification of Ni-based catalysts by coordination of dicyandiamide to Ni metal leads to enhanced selectivity for the selective hydrogenation of halonitroaromatics.The selectivity of above 99.9%to aromatic haloamines can be achieved at the conversion of 100%.The results of H_2-TPD and FT-IR experiments show that Ni^-H~＋ species possessing the properties of Lewis acid site on the surface of Raney Ni could be responsible for the hydrodehalogenation.When Raney Ni was treated by dicyandiamide,Ni^-H~＋ species interacted with N atom from the dicyandiamide.This interaction was stable even at reaction temperature,which reduced the possibility to form the intermediate state of Ar-Cl...H~＋Ni^-.And then C-Cl bond could not be polarized and activated.The hvdrodechlorination process was suppressed effectively.

关 键 词：Halonitroaromatics HYDROGENATION Ni catalyst HYDRODEHALOGENATION 

分 类 号：TQ326.82[化学工程—合成树脂塑料工业] TQ426.94