Al-SBA-15制备方法对Al-SBA-15/USY复合分子筛加氢裂化催化剂性能的影响

EFFECT OF Al-SBA-15 PREPARATION METHOD ON THE PERFORMANCE OF HYDROCRACKING CATALYST WITH Al-SBA-15/USY COMPOSITE SUPPORT

分别采用直接合成法和后合成法制备Al-SBA-15分子筛,并负载USY分子筛得到复合分子筛,以此为载体制备多产中间馏分油型加氢裂化催化剂。XRD、TEM、SEM、低温N2吸附/脱附表征证明了微孔-介孔复合分子筛的存在,且后合成法制备的复合分子筛形貌更规整,其孔径为4.86nm,比表面积为572m2/g,更适合处理重质油。采用后合成法制备的Al-SBA-15复合分子筛催化剂的中间馏分油收率和选择性比以USY分子筛为载体的催化剂分别提高2.0百分点和2.6百分点,比含直接合成法制备的Al-SBA-15复合分子筛的催化剂均提高0.6百分点。

Composite molecular sieve Al-SBA-15/USY was prepared by different Al-SBA-15 samples,which was synthesized by post-alumination procedure and direct hydrothermal synthesis respectively.The composite molecular sieve samples were characterized by XRD,SEM,TEM and N2 adsorption/desorption techniques to confirm their structure having both mesoporous and microporous characteristics.Composite molecular sieve containing post-synthesized Al-SBA-15 exhibited better morphology and pore structure,having pore diameter of 4.86 nm and specific surface area of 572 m2/g;thus it seemed more suitable for treating heavy oil.Hydrocracking catalysts for enhancing middle distillates yield were prepared by such composite supports.As compared with catalyst using single USY support,the selectivity and yield of middle distillates over catalyst with Al-SBA-15/USY support（by post-synthesis） was 2 percentages and 2.6 percentages higher,respectively;besides,it is 0.6 percentages higher compared with catalyst containing Al-SBA-15 prepared by direct synthesis.