超声波辐照浸渍法制备MnO2/γ-A12O3催化剂及其柴油催化氧化脱硫性能

 分别采用超声波辐照浸渍法和普通浸渍法制备了MnO₂/γ-Al₂O₃催化剂，运用电感耦合等离子体原子发射光谱（ICP-AES）和X射线衍射（XRD）对催化剂进行表征，在空气-异丁醛-MnO₂/γ-Al₂O₃体系中评价其对加氢柴油的氧化脱硫催化性能，并考察了反应温度、异丁醛用量、空气流量、溶剂类型和剂/油体积比对柴油氧化脱硫反应的影响。结果表明，超声波辐照浸渍法制备的MnO₂/γ-Al₂O₃催化剂对柴油氧化脱硫的催化性能明显优于普通浸渍法制备的催化剂。最适宜的催化柴油氧化脱硫反应的条件为：乙腈为溶剂、加氢柴油30 mL、温度35℃、异丁醛20 mmol、空气流量0.06 L/min、超声波辐照浸渍法制备的MnO₂/γ-Al₂O₃催化剂0.08 g、剂/油体积比1/6和催化氧化时间10 min。在此条件下可将柴油硫质量分数从542μg/g 降至31μg/g，柴油脱硫率和回收率分别为94.3%和93.3%。

Preparation of MnO2/γ-Al2O3 Catalyst by Ultrasonic Irradiation Impregnation and Its Catalytic Oxidative Desulfurization Performance for Diesel Oil

MnO₂/γ-Al₂O₃ catalysts were prepared by the methods of ultrasonic irradiation impregnation and conventional impregnation, and characterized by means of ICP-AES and XRD. Oxidative desulfurization of hydrogenated diesel was studied with the air-isobutyl aldehyde oxidation system in the presence of MnO₂/γ-Al₂O₃  catalyst. The influences of variables on oxidative desulfurization of diesel, such as reaction temperature, the amount of isobutyl aldehyde, air flow rate and volumetric ratio of solvent to oil, were investigated. The experimental results showed that the oxidation desulfurization performance of MnO₂/γ-Al₂O₃ catalyst prepared by ultrasonic irradiation impregnation was much better than that of the catalyst prepared by conventional impregnation method. Under the optimum conditions of reaction temperature 35℃, isobutyl aldehyde 20 mmol, air flow rate 0.06 L/min, MnO₂/γ-Al₂O₃  catalyst 0.08 g and volumetric ratio of acetonitrile to diesel 1/6, the sulfur mass fraction in diesel oil could be reduced from 542 μg/g to 31 μg/g and the desulfurization ratio and recovery of diesel could reach 94.3% and 93.3%, respectively.