化学液相沉积法改性HY沸石及其对萘与叔丁醇择形烷基化反应的催化性能

采用化学液相沉积法,经异丁基三乙氧基硅烷修饰并用高温水蒸气处理得到了改性HY沸石.采用X射线衍射、低温N2吸附和脉冲式质量分析技术研究了改性样品骨架结构、比表面积、孔结构参数和吸附性质的变化,并考察了HY沸石及其改性后样品对萘与叔丁醇烷基化制备2,6-二叔丁基萘(2,6-DTBN)反应的催化性能.结果表明,改性后HY沸石的骨架结构基本不变,但比表面积增大,平均孔径缩小,孔口尺寸得到了一定调变.在改性后HY沸石催化剂上萘与叔丁醇烷基化反应活性下降,但催化剂择形性能明显提高,其2,6-DTBN/2,7-DTBN比可以达到6.62。

HY Zeolite Modified by Liquid Silane Deposition and Its Catalytic Activity in Selective tert-Butylation of Naphthalene

HY zeolite was modified by chemical liquid deposition with i-C4H9Si(OC2H5)3 and a hydrothermal treatment.The samples were characterized by X-ray diffraction,N2 adsorption,and pulse mass analysis to investigate the influence of modification on the framework structure,specific surface area,pore diameter,and adsorption behavior.The catalytic activity of HY zeolite and modified HY in the alkylation of naphthalene with tert-butyl alcohol was evaluated.The modification of HY zeolite did not change the framework structure but increased the specific surface area,decreased the pore diameter,and narrowed the pore opening.The catalytic activity of the modified HY zeolite catalyst for tert-butylation of naphthalene was decreased while the shape-selectivity for 2,6-di-tert-butylnaphthalene(2,6-DTBN) was clearly increased,and a high 2,6-DTBN/2,7-DTBN ratio of 6.62 was obtained.