关键词: 磷钨酸, 担体, 丙烯齐聚, 产率, 选择性, 壬烯, 四聚丙烯

Abstract: In this paper, the propene oligomerization catalyzed by phosphotungstic acid which was fixed on two types of silica gel was studied, it has been found that the conversion rate of propene catalyzed by A type silica gel-phosphotungstic acid catalyst is 3.38%, while the conversion rate of propene catalyzed by B type silica gel-phosphotungstic acid catalyst is 90.1%, and its selectivity to nonene is 42.33%, selectivity to dodecene is 31.79%. Influence of reaction temperature, pressure and liquid hour space velocity (LHSV)catalyzed by B type silica gel-phosphotungstic acid catalyst are investigated. It has been found that when the reacting temperature increases from 170℃ to 190 ℃,the conversion rate of propene increases while the selectivity to nonene and dodecene decrease, when the reactive pressure increases from 3.5MPa to 4.5MPa,the conversion rate of propene increases also, the selectivity to nonene and dodecene changes very little.The conversion rate of propene in 0.5 h-1 LHSV, 1.0 h-1 LHSV is high than that of 2.0 h-1 LHSV, but the selectivity to nonene and dodecene does not show regular fluctuation. The optimized conversion rate, 91.05%,and optimized selectivity to nonene and dodecene, 89.51% could be achieved when the reaction temperature is 170℃, pressure is 4.5MPa and LHSV is 1.0h-1.The catalyst life experiments show that catalyst keeps activity only about 25 hours, and it had to be regenerated after that.

Key words: phosphotungstic acid, support, propene oligomerization, yield, selectivity, nonene, dodecene