Alkylation Of Benzene With Propylene And Isobutane With Butene Using Ionic Liquid As Catalyst

Ionic liquid containing aluminum trichloride, pyridine and hydrogen chloride was synthesized. The alkylation of benzene with propylene and isobutane with butene in ionic liquid was investigated in an autoclave. The experimental results indicate that ionic liquid shows perfect catalytic performance. It can be used in repeated operations and keeps its stability. When losing activity, it can be regenerated by supplying aluminum trichloride. What's more, it is easy to separate the alkylation products from the ionic liquid.By investigating the temperature, reaction time, amount of the ionic liquid, ratio of benzene to propylene or isobutene to butene, the better processing conditions were ascertained. In the range of room temperature (about 20~30 ), 100% propylene conversion and 87% selectivity of isopropyl benzene was obtained when the ratio of benzene to propylene was 8:1 in weight and the amount of catalyst was 1/3 weight of benzene; and over 97% butene conversion was obtained when the ratio of isobutene to butene was 3:1 in weight and the amount of catalyst was 1/4 weight of isobutene, if the velocity of butene was controlled. The percent of alkylation products suitable for gasoline is over 95%.At the same time, the effects of catalyst composition was investigated, the results showed that the ionic liquids with AlCl3 molar fraction from 0.65 to 0.70 have perfect catalytic performance for the title reaction, the ionic liquid with less AlCl3 is favorable for polymerization of propylene, and the ionic liquid with too much AlCl3 is favorable for formation of multalkyl products.