成品柴油氧化萃取法脱硫脱氮工艺研究

以双氧水-有机酸体系作氧化剂,采用氧化反应与溶剂萃取相结合的方法对焦化柴油进行了氧化脱氮研究。通过单因素实验确定了最适宜的氧化工艺参数为：双氧水-甲酸作氧化体系,氧化温度为70℃,氧化时间为1 min,剂油体积比为0.24,V（双氧水）/V（有机酸）为0.5。萃取实验条件为：在室温条件下,萃取剂油比为0.8,搅拌5 min。以低硫、低氮成品柴油为例,考察了氧化萃取法在最佳工艺条件下对硫、氮的深度脱除,以及对硫类型和氮类型的选择性研究。结果表明：柴油回收率为94.20%,总氮脱出率为76.39%,总硫脱出率为87.38%,这种工艺对柴油中较难脱出的咔唑、噻吩类化合物具有较好的脱出效果。

Study on Desulfurization and Denitrification of Diesel Products by Oxidation-Extraction Process

The process that combined oxidation reactions and solvent extraction for desulfurization and denitfification of coking diesel with hydrogen peroxide- organic acid as an oxidant was studied. Influences of different process conditions were investigated. The optimal operation conditions are as follow： hydrogen peroxide and formic acid solution is used as the oxidant system, oxidation temperature 70 ℃,oxidation time 1 min, volume ratio of oxidants to coking diesel 0.24,volume ratio of hydrogen peroxide to formic acid 0.5;furfural as an extractant, volume ratio of extractant to oil 0.8,extraeting at room temperature for 5 min. Taking low-sulfur, low nitrogen diesel products as an example, removal effect of sulfur and nitrogen under the best conditions was investigated as well as seleetivity of sulfur type and nitrogen type. The results show that recovery of diesel fuel is 94.20%, total denitrifieafion rate is 76.39% and total desulfurization rate is 87.38%. This process has good removal result for carbazole and thiophene compounds,which are difficult to be removed from diesel oil.