Supported Catalysts Prepared By Strong Electrostatic Adsorption For Hydrogenation Of Aromatics

Catalytic hydrogenation of aromatic compounds has attracted great attention owing to the high value in practical applications.In addition,with the increasing demand for diesel fuels,it is necessary and practically significant to eliminate toxic aromatic compounds which contains a major source of air pollution.Supported catalysts have been widely employed in catalytic hydrogenation due to their particularly metal-support interaction and highly metallic utilization.Herein,a series of supported catalysts are synthesized via an effective method strong electrostatic adsorption,and the reaction mechanism for catalytic hydrogenation of aromatics over the catalysts is studied.The main contents are as follows:（1）Firstly,supported Pd/Si O₂and Ru/Si O₂catalysts are synthesized by strong electrostatic adsorption（SEA）and their catalytic activities in isophorone hydrogenation are studied respectively.Compared to the catalysts prepared by dry impregnation,the SEA catalysts show higher catalytic activities due to the highly dispersd metallic nanoparticles.The hydrogenation results show that in the selective hydrogenation of isophorone over Pd/Si O₂catalyst,the conversion of isophorone is 77.00%and the selectivity of the product TMCH is 96.98%.Besides,in completely hydrogenation of isophorone over Ru/Si O₂catalyst,the conversion of isophorone is 99.99%and the selectivity of the product TMOL is 100%.（2）A series of alloy co-SEA@Pd-M/Si O₂（M=Pt,Ni,Cu,Co）catalysts with highly exposed and well-alloyed nanoparticles are synthesized via simultaneous strong electrostatic adsorption（co-SEA）.The toluene and benzene hydrogenation were used as probe reactions to evaluate the catalytic hydrogenation activity performance of the Pd-M/Si O₂catalysts.Compared to the catalysts synthesized by the simultaneous dry impregnation（co-DI）,the co-SEA@Pd-Ni/Si O₂catalyst exhibited the highest turnover frequencies（TOFs）of 3.7 s^-1for benzene hydrogenation and 3.2 s^-1for toluene hydrogenation.This was attributed to the large amount of electron-deficient Pd^δ+sites on the surface of SEA Pd-M/Si O₂that easily for electron-rich benzene and toluene to adsorb（3）According to the conditions and results of the isophorone hydrogenation over the Ru/Si O₂catalyst prepared by strong electrostatic adsorption,the matching process design is performed.Based on Aspen,the overall process is simulated so that the equipment and operating parameters were optimized,and the effect of energy saving is significant.