磷钨酸离子液体负载γ-Al_2O_3催化氧化-萃取脱硫

Phosphotungstic acid ionic liquids/γ-Al_2O_3 catalytic oxidation-extraction desulfurization

以γ-Al_2O_3为载体、磷钨酸离子液体为活性组分,用共沉淀法制备了[C1imCH_2CH_2COOH]_3PW_(12)O_(40)/γ-Al_2O_3(IL-HPW/γ-Al_2O_3)催化剂,并采用BET、TGA、FTIR、XRD以及SEM表征技术对催化剂进行表征分析。以质量分数为30%的H_2O_2为氧化剂,以N-甲基吡咯烷酮(NMP)为萃取剂,以含二苯并噻吩(DBT)的模拟油品进行氧化萃取脱硫反应,考察了氧化-萃取工艺条件对模拟油脱硫效果的影响。实验结果表明,在催化剂用量质量分数为0.7%(基于模拟油质量),反应时间为60min,n(H_2O_2)∶n(S)=2.5,反应温度为50℃,萃取一次的最佳条件下,其最佳脱硫率为99.2%。该催化剂在直馏柴油中也表现出较高的脱硫活性,在一定的反应条件下,使用N-甲基吡咯烷酮萃取剂萃取4次后,柴油硫含量从477mg/L降到24.4mg/L,脱硫率高达94.88%。

In the experiment, ClimCHzCH2COOH]3PW1204o/7-A1203 （IL-HPW/7-A1203）was made as a kind of catalyst by co-precipitation in the experiment using 7-Alz 03 as the carrierand phosphotungstic acid ionic liquids as the active component, characterized by BET, TGA,FTIR, XRD and SEM. The technology conditions of oxidation-extraction were investigated byoxidative desulfurization. During the process, with 30% HzOz as the oxidant, and N-methyl-2-pyrrolidone （NMP） as the extraction agent, model oil which contained dibenzothiophene （DBT）experienced extraction and oxidation desulfurization. The results showed that under an optimumcondition when the dosage of the catalyst is 0.7% （based on the mass of model oil）, the reactiontime was 60rain, n （H202） ＂ n （S） 2.5, when the reaction temperature was 50~C with onlyone-time extraction, the optimal sulfur removal was 99.2% .The catalyst showed highdesulfurization activity in straight run diesel oil as well. The sulfur content dropped from 477mg/L to 24.4mg/L after extracting it four times with NMP at the given reaction condition. The sulfurremoval was as high as 94.88%.