摘要
采用不同浓度的CH_3COONa溶液和常规碱(NaOH和Na_2CO_3)溶液处理HZSM-5分子筛,对处理前后的HZSM-5分子筛负载Pt,制备Pt/HZSM-5催化剂用于丙烷脱氢反应。利用X射线衍射(XRD)、X射线荧光光谱(XRF)、扫描电镜(SEM)、比表面测试仪(BET)、NH_3-TPD(程序升温脱附法)和H2化学吸附等手段对处理前后的HZSM-5分子筛进行表征,并考察了不同浓度的CH_3COONa溶液和常规碱溶液处理对HZSM-5分子筛的晶体结构、表面形貌、孔结构、表面酸性及丙烷脱氢性能的影响。结果表明,CH_3COONa溶液具有碱改性作用,与常规碱溶液相比,采用CH_3COONa溶液处理HZSM-5分子筛,能够在对分子筛的晶体结构和表面形貌影响较小的基础上有效地引入介孔结构,具有较好的可调控性;随着CH_3COONa溶液浓度的增加,丙烷脱氢反应的丙烷初始转化率和丙烯选择性先升高后降低,当CH_3COONa溶液浓度为4.0 mol/L时,丙烷初始转化率和丙烯选择性均达到最高值,分别为34.5%和98.9%。
HZSM-5 zeolites were treated by CH3COONa solution with different concentrations and conventional alkali (NaOH or Na2CO3) solution. Then, Pt was loaded on HZSM-5 zeolites before and after the treatment to synthesize Pt/HZSM-5 catalysts for propane dehydrogenation reaction. HZSM-5 zeolites were characterized by XRD, XRF, SEM, BET, NH3-TPD, and H2 chemisorption. The effect of CH3COONa solution with different concentrations and conventional alkali solution on crystal structure, surface morphology, pore structure, surface acidity, and propane dehydrogenation performance of HZSM-5 zeolites were investigated. The results showed that CH3COONa solution modified HZSM-5 zeolites by alkali. Compared with conventional alkali solution, the treatment of CH3COONa solution for HZSM-5 zeolites could more effectively and better controllably introduce the mesoporous structure with less influence on the crystal structure and surface morphology. With increase of the concentration of CH3COONa solution, the initial propane conversion and the propene selectivity in propane dehydrogenation firstly increased and then decreased. The catalyst treated by 4.0 mol/L CH3COONa solution exhibited the highest propane initial conversion and propene selectivity, which were 34.5% and 98.9%, respectively.
作者
徐国皓
余金鹏
徐华胜
李春成
黄金花
王鹏飞
XU Guo-Hao;YU Jin-Peng;XU Hua-Sheng;LI Chun-Cheng;HUANG Jin-Hua;WANG Peng-Fei(Shanghai Research Institute of Chemical Industry Co.,Ltd,Shanghai 200062,China;Shanghai Lüqiang New Materials Co.,Ltd,Shanghai 201608,China)
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2019年第5期546-552,共7页
Journal of Inorganic Materials
基金
上海市科技人才计划项目(15XD1522300)~~
关键词
HZSM-5
碱处理
丙烷脱氢
HZSM-5
alkali treatment
propane dehydrogenation
作者简介
徐国皓(1993-),男,硕士研究生.E-mail:1447667520@qq.com;通讯作者:王鹏飞,教授级高级工程师.E-mail:wpf@sh-lq.com.
