加氢反应催化剂中银组分功能综述

Functions of silver component in hydrogenation catalysts:a review

贵金属中的廉价金属Ag以其独特的物理化学性质在催化领域发挥了重要作用。在加氢反应中,Ag自身是一种性能优异的催化剂加氢活性组分,其显著特性是对反应物分子中含有多种加氢活性位点或者从炔烃到烯烃的部分加氢反应,能够控制加氢程度,实现选择性加氢。Ag作为催化剂助剂组分,能够提高Pt、Au和Ni催化剂选择性加氢性能、催化活性或稳定性。此外,Ag作为助剂能够降低Cu、Ni催化剂的还原温度,甚至能免除催化剂预还原步骤,还能够抑制催化剂中金属组分在酸催化体系中析出。综述单金属Ag催化剂和含Ag多金属催化剂在加氢反应中的研究进展,重点阐述Ag作为主组分或者助剂在催化剂中发挥的特殊功能。

As relatively cheap noble metal,Ag component with unique physicochemical properties plays important roles in the catalysis.It was found that Ag had excellent performance in hydrogenation reactions.The significant characteristic of Ag as the main composition of the catalysts is that it can control the extent of hydrogenation and realize selective hydrogenation for the reactions with reactant containing various hydrogenation active sites,or for the reactions from alkynes to alkenes.Besides,Ag as a promoter of the catalysts can improve hydrogenation selectivity,catalytic activity and stability of Pt,Au,Ni catalysts.In addition,Ag can reduce the reduction temperature of Cu,Ni catalysts,and even eliminate the pre-reduction step of the catalyst.Ag also can prevent the metals of catalysts from leaching into the solvents when the reactions contain acidity.The research progress of Ag-only catalysts and Ag-containing multimetallic catalysts in hydrogenation was reviewed in this paper,with the emphasis on the special functions of Ag as main component or promoter in the catalysts.