Alumina-Supported Palladium-Silver Bimetallic Catalysts with Single-Atom Pd1 Sites in the Liquid-Phase Hydrogenation of Substituted Alkynes

被引：16

作者：

Rassolov, A., V ^{[1
]}

Bragina, G. O. ^{[1
]}

Baeva, G. N. ^{[1
]}

Mashkovsky, I. S. ^{[1
]}

Stakheev, A. Yu ^{[1
]}

机构：

[1] Russian Acad Sci, Zelinsky Inst Organ Chem, Moscow 119991, Russia

来源：

KINETICS AND CATALYSIS | 2020年 / 61卷 / 06期

基金：

俄罗斯科学基金会;

关键词：

single-atom alloy catalysts; isolated Pd-1 sites; bimetallic catalysts; Pd– Ag; heterogeneous catalysts; liquid-phase hydrogenation; diphenylacetylene; 1-phenyl-1-propyne; SELECTIVE HYDROGENATION; SURFACE SEGREGATION; CU/AL2O3; CATALYSTS; ACETYLENE; AG; PHENYLACETYLENE; SEMIHYDROGENATION; METAL; MECHANISM; ETHYLENE;

D O I：

10.1134/S0023158420060129

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The catalytic characteristics of Pd-Ag/Al2O3 bimetallic catalysts with an Ag/Pd atomic ratio of 0.03-3.0 have been studied in the selective liquid-phase hydrogenation of diphenylacetylene and 1-phenyl-1-propyne. It has been found that an increase in the Ag/Pd ratio leads to a significant increase in selectivity, which, however, is accompanied by a decrease in the catalyst activity. Comparison with data of an earlier structural study suggests that an increase in selectivity observed with an increase in the Ag/Pd ratio to 0.5-1.0 is attributed to the following two factors: (1) the suppression of the formation of palladium hydride and (2) an increase in the fraction of "single-atom" Pd-1 sites isolated from each other by Ag atoms on the surface of the Pd-Ag nanoparticles. An increase in the Ag/Pd value to 2.0-3.0 leads to a further increase in the selectivity, which exceeds the selectivity of a commercial Lindlar catalyst (Pd-Pb/CaCO3). In this case, the most probable cause of the high selectivity is the formation of the single-atom Pd-1 sites on the surface of the Pd-Ag alloy and an increase in the stability of the structure.

引用

页码：869 / 878

页数：10