二异丙基萘在分子筛催化剂上的侧链断裂反应

在小型固定流化床(FFB)装置上，考察了以Y和ZSM-5分子筛作为催化剂，温度、剂/油质量比对二异丙基萘裂化侧链断裂反应的影响。结果表明，二异丙基萘在分子筛催化剂上极易发生侧链断裂反应，生成萘、C1~C4烷基萘、四氢萘、烷基四氢萘和丙烯等低碳烯烃；较少量的二异丙基萘通过脱氢缩合生成菲、芘等三环以上多环芳烃甚至焦炭。由于扩散和吸附性能的影响，二异丙基萘侧链断裂反应与催化剂的孔径有关，并与催化剂B酸量密切相关。在B酸量较少、吸附性能适宜的ZSM-5催化剂上其侧链断裂反应选择性比Y催化剂的高。当反应温度在425~525℃、剂/油质量比在3~8范围，随着反应温度升高，或者剂/油质量比增加，脱氢缩合反应增强，而烷基侧链断裂反应选择性降低。

Side-Chain Scission of Diisopropylnaphthalene Over Zeolite Catalysts

Experiments of diisopropylnaphthalene cracking over zeolite catalysts under certain reaction temperature and catalyst/oil ratio were conducted on a small fixed fluidised bed(FFB) unit.Effects of ZSM-5 and Y zeolite catalysts,temperature and catalyst/oil ratio on side chain scission of diisopropylnaphthalene were explored.The experimental results showed that the side-chain scission of diisopropylnaphthalene over zeolite catalysts occurred easily,by which the products were naphthalene,C1-C4 alkyl naphthalene and tetralin,alkyl tetralin as well as low olefin such as propylene.Less products by dehydrogenation condensation reactions were polycyclic aromatics with more than three rings(phenanthrenes,pyrenes and so on) and coke.Due to the diffusion and adsorption of alkyl aromatics on catalysts,selectivity of the side-chain scission was closely related to pore and mainly to B acid of catalysts.The selectivity of the side-chain scission was higher over ZSM-5 catalyst with weaker B acid and preferable adsorption than that over Y catalyst.At the mass hourly space velocity of 10 h-1,temperature of 425-525℃,catalyst/oil mass ratio of 3-8,reactions of dehydrogenation condensation were stronger,and selectivity of the side-chain scission was weaken with the temperature rising or catalyst/oil ratio increasing over Y catalyst.