多级孔Ni/SAPO-5萘加氢制十氢萘催化剂

以CTAB为改性剂,制备了多级孔SAPO-5-x(x为CTAB与SiO_2的摩尔比,x=0.04~0.10)分子筛和多级孔Ni/SAPO-5-x萘加氢制十氢萘催化剂.加入CTAB后形成了微-介孔多级孔孔道结构,孔容和平均孔径均有增加,但是分子筛的晶相结构没有破坏,层状的外貌没有变化.随x值的增大,SAPO-5-x(x=0~0.10)的孔容和平均孔径先增加后减小,SAPO-5-0.07的最大,Ni/SAPO-5-0.07的平均孔径进一步增大;Ni/SAPO-5-x(x=0~0.10)的强酸位强度先下降后增加,x=0.07时强酸位强度最弱,且以L酸中心为主;催化剂的十氢萘选择性先增大后减小,x=0.07时最大.引入CTAB后催化剂活性略有增加,萘转化率接近100%,十氢萘的选择性可以达到95%以上.

Hierarchical Porous Ni/SAPO-5 Catalysts of Hydrogenation from Naphthalene to Decalin

CTAB was used as modifier to prepare hierarchical porous SAPO-5-x zeolite (x is the molar ratio of CTAB to SiO₂, x=0.04~0.10) and the catalytic performances Ni/SAPO-5-x in the hydrogenation of naphthalene to decalin were studied. When the CTAB was added, the hierarchical micro-mesoporous formed. However the crystal phase structure has no been destructed and the morphology of the particles did not change. With the increase of x, the pore volume and average pore size of the SAPO-5-x first increased and then decreased, they were the largest for SAPO-5-0.07 and they increased further in Ni/SAPO-5-0.07. The strength of strong acid sites decreased first and then increased in Ni/SAPO-5-x (x=0~0.10), the strength of Ni/SAPO-5-0.07 was the weakest and the main acidic center was L acids. The catalytic selectivity of decalin increased first and then decreased, and the activity increased slightly after the introduction of CTAB, the selectivity is the greatest when x=0.07. The conversion of naphthalene is close to 100% and the selectivity of decalin is higher than 95%.