分子筛类型对四氢萘加氢裂化反应性能的影响

摘要

Ni-Mo catalysts with modified Beta,Y,ZSM-5 zeolites as carriers were prepared by equal volume impregnation method and named as CAT-B,CAT-Y and CAT Z,respectively.The catalysts were characterized by XRD,BET,NH3-TPD,Py-FTIR and H2-TPR techniques.The influence of different zeolite catalysts on activity and product selectivity for tetralin hydrocracking were investigated on a fixed bed continuous hydrogenation device.The results showed that CAT-B catalyst has a specific pore structure and surface area and higher L acid and B acid content than CAT-Y and CAT-Z catalysts.The weaker interaction between the carrier and active metals of CAT-B is beneficial to the dispersion of the metals.The order of conversion rate for tetralin hydrocracking is CAT-B＞CAT-Y＞CAT-Z.Moreover,the CAT-B catalyst has the highest selectivity to BTX and cracking products and the lowest selectivity to the condensation products at the same conversion rate of tetralin.%分别以改性Beta,Y,ZSM-5分子筛为载体,采用等体积浸渍法制备了Ni-Mo体系催化剂(分别命名为CAT-B,CAT-Y,CAT-Z),利用XRD、N2吸附-脱附、NH3-TPD、Py-FTIR、H2-TPR等手段对催化剂进行了表征.以四氢萘为模型化合物,在固定床连续加氢装置上考察了不同分子筛催化剂对四氢萘加氢裂化反应活性及产物选择性的影响.结果表明:CAT-B催化剂有较适宜的孔结构及比表面积,并且较CAT-Y和CAT-Z催化剂有较高的L酸量和B酸量,在金属组分与载体的相互作用力方面表现较弱,有利于金属组分的分散;催化剂对四氢萘加氢裂化反应转化率由高到低的顺序为CAT-B＞ CAT-Y＞ CAT-Z,在四氢萘转化率相同时,催化剂CAT-B对BTX及加氢裂化产物的选择性最高,对缩合产物的选择性最低.