A series of indium oxide‐modified Cu/SiO2catalysts were synthesized and used to produce ethanol via methyl acetate hydrogenation.In‐Cu/SiO2catalyst containing1.0wt%In2O3exhibited the best catalytic activity and stab...A series of indium oxide‐modified Cu/SiO2catalysts were synthesized and used to produce ethanol via methyl acetate hydrogenation.In‐Cu/SiO2catalyst containing1.0wt%In2O3exhibited the best catalytic activity and stability.The physicochemical properties of the synthesized catalysts were investigated using several characterization methods and the results showed that introducing suitable indium to Cu/SiO2increased the copper dispersion,diminished the copper crystallite size,and enriched the surface Cu+concentration.Furthermore,the Cu/SiO2catalyst gradually deactivated during the stability test,which was mainly attributed to copper sintering and the valence change in surface copper species.In contrast,indium addition can inhibit the thermal transmigration and accumulation of copper nanoparticles to stabilize the catalyst.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved.展开更多
This work proved that biomass-based polyols (sorbitol, xylitol, erythritol, glycerol and ethanediol) were able to be converted into high-value chemical (p-xylene) by catalytic cracking of polyols, alkylation of aromat...This work proved that biomass-based polyols (sorbitol, xylitol, erythritol, glycerol and ethanediol) were able to be converted into high-value chemical (p-xylene) by catalytic cracking of polyols, alkylation of aromatics, and the isomerization of xylenes over the SiO2-modified zeolites. Compared to the conventional HZSM-5 zeolite, the SiO2-containing zeolites considerably increased the selectivity and yield of p-xylene due to the reduction of external surface acidity and the narrowing of pore entrance. The influences of the methanol additive, reaction temperature, and types of polyols on the selectivity and yield of p-xylene were investigated in detail. Catalytic cracking of polyols with methanol significantly enhanced the production of p-xylene by the alkylation of toluene with methanol. The highest p-xylene yield of 10.9 C-mol% with a p-xylene/xylenes ratio of 91.1% was obtained over the 15wt%SiO2/HZSM-5 catalyst. The reaction pathway for the formation of p-xylene was addressed according to the study of the key reactions and the characterization of catalysts.展开更多
文摘A series of indium oxide‐modified Cu/SiO2catalysts were synthesized and used to produce ethanol via methyl acetate hydrogenation.In‐Cu/SiO2catalyst containing1.0wt%In2O3exhibited the best catalytic activity and stability.The physicochemical properties of the synthesized catalysts were investigated using several characterization methods and the results showed that introducing suitable indium to Cu/SiO2increased the copper dispersion,diminished the copper crystallite size,and enriched the surface Cu+concentration.Furthermore,the Cu/SiO2catalyst gradually deactivated during the stability test,which was mainly attributed to copper sintering and the valence change in surface copper species.In contrast,indium addition can inhibit the thermal transmigration and accumulation of copper nanoparticles to stabilize the catalyst.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved.
基金supported by the National Key R&D Program of China (No.2018YFB1501404)
文摘This work proved that biomass-based polyols (sorbitol, xylitol, erythritol, glycerol and ethanediol) were able to be converted into high-value chemical (p-xylene) by catalytic cracking of polyols, alkylation of aromatics, and the isomerization of xylenes over the SiO2-modified zeolites. Compared to the conventional HZSM-5 zeolite, the SiO2-containing zeolites considerably increased the selectivity and yield of p-xylene due to the reduction of external surface acidity and the narrowing of pore entrance. The influences of the methanol additive, reaction temperature, and types of polyols on the selectivity and yield of p-xylene were investigated in detail. Catalytic cracking of polyols with methanol significantly enhanced the production of p-xylene by the alkylation of toluene with methanol. The highest p-xylene yield of 10.9 C-mol% with a p-xylene/xylenes ratio of 91.1% was obtained over the 15wt%SiO2/HZSM-5 catalyst. The reaction pathway for the formation of p-xylene was addressed according to the study of the key reactions and the characterization of catalysts.