摘要
针对在保持高选择性的前提下抑制催化剂的快速积炭失活问题,利用X射线衍射(XRD)、氨气程序升温脱附(NH_(3)-TPD)、N_(2)物理吸附-脱附(BET)和吡啶吸附傅里叶变换红外光谱(Py-FT-IR)等手段对水热处理后的HZSM-5催化剂进行表征,并详细考察了水热处理条件对反应性能的影响。结果表明,水热处理温度和时间对催化剂稳定性有显著影响,最佳水热处理条件为T=550℃、t=3 h、MHSV H_(2)O=1 h^(-1)。其中HT-550-3-1催化剂稳定性表现最好,反应32 h后乙苯转化率仅降低了2.6百分点,热重分析发现其炭质量损失率(1.38%)远低于HZSM-5的炭质量损失率(5.08%)。在最佳水热处理条件下的HZSM-5分子筛经过硅(Si)、镧(La)复合改性制得的HT-9%Si-4%La催化剂,在反应温度340~370℃、压力101.325 kPa、乙苯质量空速5 h^(-1)、n(C_(8)H_(10))/n(C_(2)H_(4))=5、n(N_(2))/n(C_(2)H_(4))=11.3的反应条件下,乙苯转化率高于12.1%,对二乙苯选择性超过97.0%,催化剂稳定运行454 h。
Aiming at the problem of inhibiting the rapid coke deposition and deactivation of catalyst while maintaining high selectivity,HZSM-5 catalyst after hydrothermal treatment was characterized using X-ray diffraction(XRD),ammonia temperature programmed desorption(NH_(3)-TPD),N_(2) physisorption-desorption(BET),and pyridine adsorption Fourier transform infrared spectroscopy(Py-FT-IR),and the effects of hydrothermal treatment conditions on the reaction performance were investigated in detail.The results show that the temperature and time of hydrothermal treatment have a great effect on the stability of the catalyst,and the optimum hydrothermal treatment conditions are as follows:T=550℃,t=3 h,MHSV H_(2)O=1 h^(-1).HT-550-3-1 catalyst exhibits the best catalytic stability,of which the ethylbenzene conversion rate is decreased by only 2.6 percentage points after a 32 h reaction,and the carbon mass loss rate(1.38%)is much lower than that of the HZSM-5(5.08%),as indicated by the thermogravimetric analysis.Under these conditions,the hydrothermally treated HZSM-5 was modified by silicon and lanthanum to obtain HT-9%Si-4%La catalyst,which can stably operate for 454 h in the following reaction conditions:reaction temperature of 340—370℃,pressure of 101.325 kPa,ethylbenzene mass space velocity of 5 h^(-1),n(C_(8)H_(10))/n(C_(2)H_(4))=5,n(N_(2))/n(C_(2)H_(4))=11.3;as a result,the ethylbenzene conversion rate and p-diethylbenzene selectivity are above 12.1%and 97.0%,respectively.
作者
任印腾
张安峰
韩贺
张嘉兴
郭新闻
REN Yinteng;ZHANG Anfeng;HAN He;ZHANG Jiaxing;GUO Xinwen(State Key Laboratory of Fine Chemicals,Department of Catalysis Chemistry and Engineering,School of Chemical Engineering,Dalian University of Technology,Dalian 116024,China)
出处
《石油学报（石油加工）》
EI
CAS
CSCD
北大核心
2023年第1期54-67,共14页
Acta Petrolei Sinica(Petroleum Processing Section)
基金
国家自然科学基金青年项目(22008019)
中国博士后科学基金项目(2021T140083)
大连理工大学大型仪器设备开放基金项目(DUTKFJJ2021128、DUTKFJJ2021100)
兴辽英才项目(XLYC2008032)资助。
关键词
HZSM-5
水热处理
酸性质
抗积炭
乙苯乙烯烷基化
HZSM-5
hydrothermal treatment
acid property
coke deposition resistance
ethylbenzene-ethylene alkylation
作者简介
第一作者:任印腾,男,硕士研究生,从事分子筛择形催化研究,E-mail:renyinteng@163.com;通讯联系人:郭新闻,男,教授,博士,从事钛硅分子筛、纳米分子筛的合成及应用方面的研究,Tel:0411-84986133,E-mail:guoxw@dlut.edu.cn。
