CuCl对Et3NHCl/AlCl3离子液体催化性能的影响

 用CuCl对Et3NHCl/AlCl3离子液体进行改性,并考察了其对异丁烷-丁烯烷基化反应的催化性能. 结果表明,烷基化油的收率达到178%,C8组分的含量达到85%,辛烷值(RON)达到94.8. 通过结构组成及电荷分布分析可知,在CuCl改性的Et3NHCl/AlCl3离子液体中形成了新的配位结构AlCl4CuCl-,它作为更好的碳正离子受体,在反应过程中可降低碳正离子的浓度,进而降低烯烃的聚合程度,抑制较长碳链烷烃的生成,改善烷基化油的组成.

Effect of CuCl Additive on Catalytic Performance of Et3NHCl/AlCl3 Ionic Liquid in C4 Alkylation

In order to solve the highly corrosive and environmentally detrimental problem caused by the use of sulfuric acid and hydrofluoric acid as catalysts in alkylation of isobutane and butene, the environmentally benign acidic ionic liquid with CuCl additive was investigated as the catalyst for alkylation of isobutane and butene. The results showed that the modified ionic liquid was an excellent catalyst for the reaction, the yield of alkylate reached 178% to the butene volume, the total C 8 content in product alkylate was up to 85% and the RON of product alkylate was 94 8. The ratio of trimethylpentanes (TMP) to dimethylhexanes (DMH) in the product alkylate, which is considered as an important criterion for examining the alkylate quality (higher TMP/DMH ratio implies higher RON), increased sharply from 1 1 to 6 5 with the CuCl additive. The large change in catalytic activity of the modified ionic liquid was due to the formation of AlCl 4CuCl - species, which acted as a good acceptor for carbonium ions so as to hold back the formation of longer carbon chains.