摘要
将H-ZSM-5分子筛与Zr基氧化物进行复合,经过硫酸处理后,合成H-ZSM-5/w ZrO_(2)/SO_(4)^(2-)(w分别为40%、50%、60%)固体酸复合催化剂。采用X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)及NH_(3)程序升温吸附-脱附(NH_(3)-TPD)等分析手段对催化剂进行表征,并在固定床反应装置上考察了不同催化剂催化异丁烯-异丁烷烷基化反应性能。结果表明:经过硫酸处理后,催化剂中单斜晶相m-ZrO_(2)转化为对烷基化反应有利的四方晶相t-ZrO_(2);H-ZSM-5/50%ZrO_(2)/SO_(4)^(2-)固体酸复合催化剂具有最高的总酸量和中强酸酸量,中强酸是催化异丁烯-异丁烷烷基化反应的控制因素;同时也证实了H-ZSM-5和ZrO_(2)2种组分在复合催化剂中具有协同作用。在压力为1.4 MPa、温度为80℃、原料进料体积流速为2.0 mL/h、载气体积流速为1200 mL/h、反应时间为120 min的条件下,H-ZSM-5/50%ZrO_(2)/SO_(4)^(2-)复合催化剂作用下产物C_(8)选择性最高为83.0%,异丁烯最高转化率为94.1%,反应稳定后异丁烯转化率保持在55.2%,收率保持在45.8%,说明H-ZSM-5/50%ZrO_(2)/SO_(4)^(2-)固体酸复合催化剂具有良好的催化反应性能。
H-ZSM-5/w ZrO_(2)/SO_(4)^(2-)(w=40%,50%and 60%,respectively)solid acid composite catalyst was synthesized by compounding H-ZSM-5 zeolite with Zr-based oxide and treating with sulfuric acid.The catalyst was characterized by means of X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS)and NH_(3) temperature programmed desorption(NH_(3)-TPD),and the isobutene-isobutane alkylation reaction performance of different catalysts was investigated in a fixed bed reactor.The results show that the monoclinic m-ZrO_(2)in the catalyst is converted into the t-ZrO_(2)which is beneficial to alkylation reaction after sulfuric acid treatment;H-ZSM-5/50%ZrO_(2)/SO_(4)^(2-)solid acid composite catalyst has the highest total acid content and moderately strong acid content,and the latter is the controlling factor for catalyzing isobutene-isobutane alkylation reaction;it has also been confirmed that the two components of H-ZSM-5 and ZrO_(2)have a synergistic effect in the composite catalyst.When the pressure is 1.4 MPa,temperature is 80℃,feed volume flow rate of raw materials is 2.0 mL/h,carrier gas volume flow rate is 1200 mL/h and reaction time is 120 min,H-ZSM-5/50%ZrO_(2)/SO_(4)^(2-)composite catalyst has the highest selectivity for C_(8) up to 83.0%,the highest conversion rate of isobutene is 94.1%,the conversion rate of isobutene is 55.2%after stable reaction,and the yield remains at 45.8%,indicating that H-ZSM-5/50%ZrO_(2)/SO_(4)^(2-)solid acid composite catalyst has a good catalytic performance.
作者
田鑫
李欣
王薇
吕鹏
马保军
TIAN Xin;LI Xin;WANG Wei;Lü Peng;MA Baojun(State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering,Ningxia University,Yinchuan 750021,China)
出处
《石油学报(石油加工)》
EI
CAS
CSCD
北大核心
2022年第5期1042-1051,共10页
Acta Petrolei Sinica(Petroleum Processing Section)
基金
国家自然科学基金项目(21862014)
宁夏重点研发计划项目(2019BDE03003)
宁夏科技创新团队项目(2020CXTDLX08)资助。
关键词
固体酸复合催化剂
分子筛
固定床
烷基化反应
协同作用
solid acid composite catalyst
zeolite
fixed bed
alkylation reaction
synergistic effect