吡啶离子液体催化作用下的FCC汽油烷基化脱硫

Alkylation desulfurization of FCC gasoline catalyzed by pyridine ionic liquid

合成一种Brnsted酸性离子液体[BPY]HSO4,采用红外光谱和核磁共振对其进行表征。以[BPY]HSO4为催化剂,对FCC汽油进行烷基化脱硫,考察反应温度、反应时间和剂油质量比对脱硫效果的影响及脱硫前后FCC汽油性质的变化,并对[BPY]HSO4进行了再生。结果表明,在反应温度为65℃、反应时间为90 min和剂油质量比为0.09的条件下,FCC汽油的硫含量从580.0μg/g降至6.4μg/g,脱硫率为98.90%,满足中国国Ⅴ车用汽油硫含量标准(<10μg/g);脱硫前后硫分布变化表明,在[BPY]HSO4的催化作用下,前170℃馏分油中硫化物大部分转移到后170℃重馏分中,重馏分中硫化物可采用加氢方法进行脱除;PONA组成变化表明,烷基化脱硫过程对FCC汽油的烃类组成影响较小,且脱硫前后辛烷值变化不大;[BPY]HSO4经萃取再生后可循环使用。

Brφnsted acidic ionic liquid [BPY]HSO4 was synthesized and characterizedb y FT-IR and 1 H-NMR. [BPY]HSO4 was then used as a catalyst in alkylation desulfurization of FCC gasoline; the effects of the reaction temperature, time and mass ratio of ionic liquid to oil on the desulfurization efficiency and FCC gasoline quality w ere investiga ted.The results showed that after reacti on fo r 90 min under 65 ℃ and an ion ic liquid to oil mas ratio of〈 0.09, the sulfu r content of FCC gasoline is decreased from 580.0 to 6.4 μg/g, with a desulf urization rate of 98.90%, whi ch can meet the request of Chinese NationalS tandard V for the sulfur content in motor gasoline （〈10 μg /g）.A sur vey on th e distributio n ofs ulfur compounds indicated that sulfur compounds are transferred from light fraction （〈170 ℃） to heavy fraction （〉170 ℃） with the help of [BPY]HSO4 and the sulfur compounds in heavy fraction can then be removed further by hydrodesulfurization.PONA results indicated that the alkylation desulfurization catalyzed by [BPY] HSO4 has little effect on hydrocarbon composition and octane number of FCC gasoline.Moreover, the [BPY]HSO4 ionic liquid can be recycled through extraction and reused in the alkylation desulfurization.