摘要
分别以γ Al2 O3 、无定形硅铝和含少量稀土分子筛的γ Al2 O3 为载体 ,制备了不同系列的NiW体系加氢脱硫催化剂 ,并在连续流动微反装置上评价了催化剂对 4 ,6 二甲基二苯并噻吩 (DMDBT)加氢脱硫反应的催化性能 .结果表明 ,NiW体系催化剂对该反应具有较高的芳烃加氢和脱硫活性 ;先加氢后脱硫是加氢脱硫 (HDS)反应的主要途径 ,提高加氢活性是提高HDS活性最有效的途径 ;增强载体的酸性 ,直接脱硫和裂解活性均有所提高 .同时 ,酸性载体负载的催化剂还显示出一定的异构化性能 ,但其加氢活性低于氧化铝负载的催化剂 .酸性载体负载的NiW催化剂的异构化性能在邻二甲苯异构化反应中得到进一步证实 .根据实验结果 。
NiW based catalysts supported on γ Al 2O 3, amorphous silica alumina and rare earth HY zeolite containing γ Al 2O 3, respectively, were prepared by incipient wetness co impregnation method. Hydrodesulfurization (HDS) of 4,6 dimethyldibenzothiophene (DMDBT) was performed in a continuous flow microreactor under the conditions of p =4 14 MPa and θ =270～330 ℃. The DMDBT was dissolved in decane to obtain 0 1% sulfur solution. The liquid products were analyzed by GC FID equipped with a capillary column. The results showed that the NiW based catalysts exhibit better performance for desulfurization and hydrogenation of DMDBT, and the main product is dimethylcyclohexylbenzene with selectivity of 59 4%. The enhancement of hydrogenation activity is the most effective way to increase HDS activity. The enhancement of support acidity favors direct desulfurization and leads to a small amount of cracking products. NiW catalysts on acidic supports can transform DMDBT into isomers by migrating methyl groups adjacent to the S atom, which also favors desulfurization of DMDBT. However, their hydrogenation activity is inferior to that of alumina supported sample. Based on the experimental results, the different reaction pathways of DMDBT transformation were proposed.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
2002年第3期271-275,共5页
基金
国家重点基础研究发展规划资助项目 (G2 0 0 0 0 480 0 3 )
