NiWP/Hβ-Al_2O_3催化剂的柴油加氢性能

Performances of NiWP/Hβ-Al_2O_3 catalyst in the hydrogenation of diesel oil

采用NaOH溶液对Hβ沸石进行扩孔处理,得到含有等级孔的Hβ沸石,将其与Al2O3机械研磨制备混合载体,采用等体积浸渍法制备了NiWP/Hβ-Al_2O_3催化剂。在小型固定床反应器上,进行催化裂化柴油加氢精制实验。采用FTIR、XRD、BET、N_2吸附-脱附等手段对载体及催化剂试样进行了表征。考察了反应温度、压力、液态空速及氢油体积比等反应条件对催化剂加氢性能的影响。表征结果显示,加入Hβ沸石后,催化剂的比表面积增大,强酸量和B酸量增加,开环裂化性能增强。实验结果表明,在温度360℃、压力8 MPa、液态空速1.0h^(-1)、氢油体积比800的条件下,脱硫率达99.77%,十六烷值可提高至55.39。

Hierarchically mesoporous Hβ zeolite was obtained by the desilication of Hβ zeolite with NaOH solution. Then composite Hβ-Al2O3 support was prepared from the hierarchically mesoporous Hβ zeolite and Al2O3 through mechanical mixing. A bifunctional catalyst, NiWP/Hβ-Al2O3, was prepared by impregnation method. The support and catalyst were characterized by means of FTIR, XRD, BET and N2 adsorption desorption. The effects of temperature, pressure, LHSV and HJoil volume ratio on the performances of the catalyst in the hydrogenation were investigated in a small- scale fixed bed reactor with fluid catalytic cracking（FCC） diesel oil as raw material. The results showed that, the performances of NiWP/Hβ-AI203 with large specific surface area and many strong acid and B acid sites were enhanced by the introduction of the hierarchically mesoporous Hβ zeolite. Under the optimum conditions of temperature of 360 ℃, pressure of 8 MPa, LHSV of 1.0 h^-1 and H2/oil volume ratio of 800, the desulfurization rate and the cetane number reached 99.77% and 55.39, respectively.