离子液体催化C_5馏分中二烯烃的聚合反应

合成了多种基于1-丁基-3-甲基咪唑阳离子的离子液体,并作为裂解C5馏分中混合二烯烃聚合反应的介质。考察了离子液体种类、反应温度、反应时间和添加Lew is酸对混合二烯烃聚合反应的影响。实验结果表明,以硝酸根为阴离子的离子液体对混合二烯烃的聚合反应具有一定的阻聚作用;以六氟磷酸根为阴离子的离子液体能明显促进混合二烯烃的聚合反应,提高二聚物的含量;添加Lew is酸(质量分数为1%的ZnCl2)的离子液体对混合二烯烃的聚合反应具有更明显的促进作用,其效果仅次于酸性氯铝酸类离子液体,反应温度以30℃以下为宜,温度过高将促使二聚物进一步聚合,形成三聚物乃至多聚物,降低二聚物的含量。

Polymerization of Dienes in C5 Fraction by Ionic Liquid Catalyst

A series of ionic liquids based on 1-butyl-3-methyl imidazolium cation were prepared.Dimerization of dienes mixture in C5 fraction which came from hydrocarbon cracking was carried out in ionic liquids as catalysts.Effects of ionic liquids with different anions,reaction temperature,reaction time and addition of Lewis acid on dimerization were investigated.Ionic liquids with nitrate radical anion show inhibitive effect,but with hexafluorophosphate radical can promote dimerization and increase yield of dimers.Addition of 1%(mass fraction)ZnCl2 as Lewis acid to ionic liquids results in more rapid dimerization.Dimerization temperature must be strictly controlled below 30 ℃,otherwise would lead to further polymerization and decrease yield of dimers.