关键词:

钛硅分子筛, 纳米碳纤维, 混合, 过滤, 环己酮氨氧化

Abstract:

Carbon nanofiber (CNF) is a novel carbon based catalyst support.A TS-1/CNF composite catalyst was synthesized in liquid phase by using a method of mechanical blending.The filtration performance of the blended TS-1/CNF composite in aqueous system and its catalytic performance on ammoximation of cyclohexanone were studied.As compared with pristine TS-1 catalyst, the TS-1/CNF composite was comprised of relatively larger particles, which could be easily filtrated from the aqueous system.Meanwhile, there were a great number of macro pores in agglomerates of TS-1/CNF composite formed via CNF interweaving, in favor of liquid penetration through the filter layer of TS-1/CNF.The SEM images revealed that TS-1 particles were uniformly adsorbed on CNF surface.The unique long filament and large external surface of CNF might offer abundant adhesion sites to TS-1 particles. Strong inter-molecular, electrostatic and hydrophobic forces might exist between TS-1 particles and CNF, preventing the supported TS-1 from detaching off the CNF during stirring and filtering.The results of ammoximation of cyclohexanone over the blended TS-1/CNF composite catalyst showed that the conversion of cyclohexanone and the yield of oxime could reach 100% and 98.4%, respectively, as high as those obtained over pristine TS-1 catalyst.

Key words:

钛硅分子筛, 纳米碳纤维, 混合, 过滤, 环己酮氨氧化