有机钼多金属氧酸盐在柴油氧化脱硫中的应用

摘要

通过复分解法合成了3种基于 Mo8 O4-26阴离子的四烷基铵钼多金属氧酸盐,并将其作为催化剂,质量分数为30%H2 O2溶液为氧化剂、1-己基-3-甲基咪唑四氟硼酸盐离子液体([C6 MIM]BF4)为萃取剂,用于柴油的催化氧化脱硫。分别考察了催化剂摩尔分数、反应温度、剂油体积比、反应时间、氧化剂用量等条件对模拟油品脱硫率的影响,确定了最优化反应条件,并将其应用于实际油品的脱硫中。结果表明,在60℃反应条件下,反应时间1 h,当催化剂摩尔分数为5%、剂油体积比为1∶5、n(氧化剂)/n(硫化物)为6∶1时,该催化氧化-萃取体系对模拟油品(初始含硫质量分数为1164μg/g)有较高的脱硫率,一次脱硫率可达95%以上。对抚顺石化公司生产的催化裂化柴油(初始含硫质量分数为850μg/g)一次脱硫率约为92%。%Three kinds of molybdenum polyoxometalates using Mo8 O4-26 as the anion,quaternary ammonium salts as the cation have been synthesized.And the catalysts were used in the catalysis and oxidation desulfurization of diesel fuel system with oxidant H2 O2 (30%)as oxidant and extractant [C6 MIM]BF4 as extraction agent.The desulfurization of model diesel fuel was optimized by investigating different reaction conditions,such as the dosage of catalysts,reaction temperature,the ratio of [C6 MIM]BF4 and diesel fuel ,reaction time,the dosage of oxidant and so on and were applied in real diesel fuel.The results showed that the best desulfurization rate at 60 ℃ was obtained after 1 h under the condition of n(catalyst)/n(sulfide)=5%, V([C6MIM]BF4)/V(oil)=1∶5,n(oxidant)/n(sulfide)=6∶1.The desulfurization rate reached 95% for the model diesel fuel ([S]o=1 164μg/g)and 92% for the FCC diesel([S]o=850μg/g).