摘要
纳米堆积ZSM-5分子筛具有良好的扩散与传质能力,在各类催化和吸附方面表现出优异的性能。采用两步变温法制备纳米堆积ZSM-5分子筛,通过X射线衍射光谱、扫描电子显微镜、N 2吸附-脱附、氨气程序升温脱附、X射线荧光光谱分析、X射线光电子能谱分析等手段对合成的分子筛样品进行表征。采用偏三甲苯异构化反应表征纳米堆积ZSM-5分子筛的催化性能。结果表明:两步变温法比传统法更快合成分子筛(10 h);初级晶粒粒径为100~200 nm,晶粒堆积组成的团聚体尺寸更小,约为800 nm;两步变温法所合成的样品外比表面积最大可达53.92 m^(2)/g,与传统法相比酸性无明显变化。偏三甲苯异构化在MHSV=5.28 h-1、T=350℃、p=0.8 MPa的反应条件下,两步变温法合成样品(低温4 h,高温24 h)比传统法合成样品的性能显著提高,偏三甲苯转化率提高了14.1百分点,均三甲苯收率和选择性分别提高了8.5百分点和2.0百分点。
Nano-stacked ZSM-5 zeolite demonstrates exceptional performance in various catalysis and adsorption processes due to its good diffusion and mass transfer capabilities.Nano-stacked ZSM-5 zeolite was prepared using a two-step temperature variation method.The synthesized zeolite samples were characterized by X-ray diffraction spectroscopy,scanning electron microscopy,N 2 adsorption-desorption analysis,ammonia temperature-programmed desorption,X-ray fluorescence spectrometer,and X-ray photoelectron spectrometer.The catalytic performance of the nano-stacked ZSM-5 aeolite was evaluated through 1,2,4-trimethylbenzene isomerization reaction.The results indicate that the two-step temperature variation method can synthesize the zeolite faster than traditional methods(10 h);the primary grain size is approximately 100—200 nm,whereas the aggregate size formed by grain stacking is smaller,around 800 nm;the externally specific surface area of the zeolite samples synthesized by two-step temperature variation method can reach a maximum of 53.92 m^(2)/g,with no significant change in acidity compared to traditional methods.Under the reaction conditions of 1,2,4-trimethylbenzene isomerization:the molar hourly space velocity(MHSV)=5.28 h-1,T=350℃,and p=0.8 MPa,the zeolite samples synthesized by two-step temperature variation method(at a low temperature for 4 h,at a high temperature for 24 h)exhibit significantly higher performance compared with those synthesized by traditional methods,demonstrating a 14.1%increase in 1,2,4-trimethylbenzene conversion,a 8.5%increase in 1,3,5-trimethylbenzene yield,and a 2.0%increase in selectivity.
作者
宋金锐
梁亚凝
张燕挺
张红智
李宁
刘景怡
丁云龙
侯楠
李晓峰
SONG Jinrui;LIANG Yaning;ZHANG Yanting;ZHANG Hongzhi;LI Ning;LIU Jingyi;DING Yunlong;HOU Nan;LI Xiaofeng(College of Chemical Engineering and Technology,Taiyuan University of Technology,Taiyuan 030024,China;SINOPEC Catalyst Beijing Co.,Ltd.,Beijing 102400,China)
出处
《石油学报(石油加工)》
北大核心
2025年第2期489-497,共9页
Acta Petrolei Sinica(Petroleum Processing Section)
关键词
ZSM-5分子筛
两步变温法
晶种溶液
纳米堆积
偏三甲苯异构化
ZSM-5 zeolite
two-step temperature variation method
seed solution
nano-stacked
1,2,4-trimethylbenzene isomerization
