离子液体1-烷基-3-羧甲基苯并咪唑双三氟甲磺酰亚胺盐的合成及在油品中的脱硫应用

Synthesis of ILs 1-Alkyl-3-carboxymethyl Benzimidazole Double Trifluoromethanesulfonimide and Application in Desulfurization of Fuels

合成并表征了一类新型离子液体1-烷基-3-羧甲基苯并咪唑双三氟甲磺酰亚胺盐,将其与双氧水组合用于脱除模型油中的硫化物.结果表明,当模型油与萃取/催化剂1-辛基-3-羧甲基苯并咪唑双三氟甲磺酰亚胺盐([C_2O_2OBIM][Tf2N])的质量比为5∶1,H_2O_2/S摩尔比为5∶1,于75℃反应1 h后,模型油中二苯并噻吩(DBT)脱硫率为98.8%;脱硫过程符合一级动力学方程,5种硫化物的脱硫速率大小顺序为二苯并噻吩(DBT)>4,6-二甲基二苯并噻吩(4,6-DMDBT)>苯并噻吩(BT)>2,5-二甲基噻吩(2,5-DMT)>噻吩(T),其中脱除DBT和BT的反应表观活化能分别为44.16和52.10 k J/mol.该离子液体循环再生使用14次,脱硫率无明显下降.该深度脱硫方法具有操作简便及条件温和的特点.

A new class of ionic liquids（ ILs） 1-alkyl-3-carboxymethyl benzimidazole double trifluoromethanesulfonimide was synthesized and characterized. Ionic liquids and hydrogen peroxide were tested in extractionoxidative desulfurization system,the sulphur removal efficiency of S-compounds in the model oil was investigated. The results showed that the 1-butyl-3-carboxymethyl double trifluoromethanesulfonimide salt（ [C_2O_2OBIM][Tf_2N]） was both extractant and catalyst,n（ H_2O_2） ∶ n（ DBT） = 5 ∶ 1,m（ Model oil） ∶m（ Ionic liquid） = 5 ∶ 1,at 75 ℃ for 1 h. The ratios of desulfurization to the model oil of dibenzothiophene（ DBT） reached 98. 8%. All oxidation desulfurization processes conformed to the pseudo first-order kinetics equation. The sulfide removal rate of the order of five sulfide is dibenzothiophene（ DBT） 4,6-dimethyldibenzothiophene（ 4,6-DMDBT） thianaphthene（ BT） 2,5-dimethylthiophene（ 2,5-DMT） thiophene（ T）.The apparent activation energy of removal of DBT and BT is 44. 16 and 52. 10 k J/mol,respectively. Ionic liquid can be recycled for 14 times with an unnoticeable decrease in desulfurization activity. The method can realize deep desulfurization the depth and have the advantages of both simple operation and mild reaction condition.