文献类型：期刊文献

英文题名：Catalytic Performance of Modified ZSM-5 Designed with Selectively Passivated External Surface Acidity by Phosphorus

作者：Yi, Dezhi[1];Meng, Xuan[1];Xu, Xin[2];Liu, Naiwang[1];Shi, Li[1]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]Northwestern Univ, Appl Phys, Evanston, IL 60208 USA

年份：2019

卷号：58

期号：24

起止页码：10154

外文期刊名：INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH

收录：;EI(收录号：20192507073735);WOS:【SCI-EXPANDED(收录号:WOS:000472683200003)】；

基金：We acknowledge financial support from the National Science Foundation for Young Scientists of China (No. 21706065) and Open Project of State Key Laboratory of Chemical Engineering of East China University of Science and Technology (No. SKL-ChE-18C02). N.L. is grateful for the Shanghai Sailing Program (No. 18YF1406300) and China Postdoctoral Science Foundation (No. 2017M621389).

语种：英文

外文关键词：Passivation - Textures - Xylene - Ammonia - Nuclear magnetic resonance spectroscopy

摘要：A phosphorus modified HZSM-5 sample with excellent p-xylene selectivity was successfully obtained by a method of reversing the external surface ZSM-5 crystals to positive charged by HDTMA, which could selectively deposit the phosphorus on the external surface and pore entrance. The texture properties were characterized by XRD, XRF and N-2 adsorption-desorption. The accessibility of acid sites was determined by NH3-TPD and Py/Coll-IR. The solid-state NMR measurement indicated that more phosphorus did not enter the pores of the MZS-1.5P sample and existed as H4P2O7 or polyphosphates not connected to aluminum. Applied to alkylation of toluene with methanol, MZS-1.5P sample all exhibited excellent para-selectivity at reaction temperatures of 360-420 degrees C and WHSV of 1.0-4.0 h(-1). The TPD of xylene analysis showed that the interactions between diffusing molecule and surface of ZSM-5 as well as the geometric factors play important roles in the diffusion process.