磷钨介孔分子筛催化直馏柴油氧化脱硫工艺条件及反应动力学研究

以介孔分子筛SBA-15为载体,磷钨酸为活性组分,采用一锅法工艺制备出磷钨介孔催化剂,使用X射线衍射、透射电子显微镜等分析手段表征了催化剂的结构与性能。在磷钨介孔催化剂存在下,以过氧化氢为氧化剂,研究了工艺条件对辽河油田直馏柴油催化氧化脱硫效果的影响并获得了反应动力学数据。结果表明,磷钨酸负载SBA-15分子筛催化剂具有完整二维六方介孔结构。最佳负载量(质量分数)为30%时,在V(双氧水溶液)/V(直馏柴油)为0.05,m(催化剂)/V(直馏柴油)为0.03 g/mL,氧化温度为70℃,氧化时间为1.5 h的最佳工艺条件下,直馏柴油的脱硫率为80.08%;直馏柴油的氧化脱硫反应为一级反应,表观活化能为37.86 kJ/mol,指前因子为7 210.47。

Study on process condition and reaction kinetics of oxidation desulfurization of straight-run diesel oil over phosphotungstic acid/mesoporous zeolite catalyst

The phosphotungstic acid/mesoporous zeolite catalyst was prepared by one-pot process with phosphotungatic acid as active component,mesoporous zeolite SBA-15 as carrier,and the structure and performance of the catalyst were characterized by X-ray diffetaction and transmission electron microscopy etc.In the existance of the catalyst and with H2O2 as oxidant the effect of process condition on the oxidation desulfurization of Liaohe straight-run diesel oil was investigated,and the data for reaction kinetics were obtained.The results showed that the phosphotungstic acid supported SBA-15 zeolite catalyst had a complete two dimensional hexagonal mesoporous structure,and the optimal loading mass fraction of phosphotungstic acid was 30%.Under the optimal condition of V（H2O2）/V（straight-run diesel oil） 0.05,m（catalyst）/V（straight-run diesel oil）0.03g/mL,oxidation temperature 70℃,oxidation time 1.5h,the desulfurization percent was 80.08%.The oxidation desulfurization reaction followed the first order kinetics,its apparent activation energy Ea was 37.86kJ/mol,the pre-exponential factor A was 7210.47.