酸性离子液体萃取/催化二苯并噻吩氧化脱硫反应的优化

ö以Brönsted酸性离子液体N-甲基-2-吡咯烷酮磷酸二氢盐([Hnmp]H₂PO₄)为萃取剂和催化剂，双氧水为氧化剂，二苯并噻吩(DBT)溶于正辛烷为模型油，利用正交实验法优化了DBT氧化脱硫反应工艺。所优化的反应条件为：反应温度60℃，模型油与离子液体体积比为1∶1，氧/硫摩尔比为16， 氧化时间5h；在此条件下模型油脱硫率达99.8%，实际柴油脱硫率为64.3%。由正交实验极差可知，各因素对DBT脱硫率影响的大小依次为：反应温度＞反应时间＞氧/硫摩尔比＞剂油比；离子液体循环利用6次，脱硫率下降不明显。

Optimization of oxidative desulfurization of dibenzothiophen using acidic ionic liquid as catalytic solvent

The oxidative desulfurization of dibenzothiophene (DBT) in n-octane as model oil with Brnsted acidic ionic liquids (ILs) N methyl-pyrrolidonium phosphate ([Hnmp]H₂PO₄) as catalytic solvent and H₂O₂ as oxidant was optimized by orthogonal experiments. 99.8% of DBT in the model oil was removed under the optimal conditions of molar ratio of H₂O₂ to sulfur of 16∶1, reaction temperature of 60℃, reaction time of 5h, and volume ratio of model oil to ILs of 1∶1. The desulfurization efficiency of actual diesel was 64.3% under the optimized conditions. The influences of the desulfurization efficiency of DBT decreased in the following order: oxidation temperature > oxidation time> molar ratio of H₂O₂/sulfur (O/S) > volume ratio of [Hnmp]H₂PO₄ to model oil (VIL/Vmodel oil), according to extreme analysis of orthogonal test. The IL [Hnmp]H₂PO₄ can be recycled six times without a significant decrease in activity.