Role of Acidity in the Ethylation of Coking Benzene with Ethanol over Nanosized HZSM-5
发表时间:2019-03-09
点击次数:
- 论文类型:
- 期刊论文
- 第一作者:
- Sun, Linping
- 通讯作者:
- Guo, XW (reprint author), Dalian Univ Technol, Sch Chem Engn, State Key Lab Fine Chem, Dept Catalysis Chem & Engn, Dalian 116012, Peoples R China.
- 合写作者:
- Guo, Xinwen,Liu, Min,Wang, Xiangsheng
- 发表时间:
- 2010-01-20
- 发表刊物:
- INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
- 收录刊物:
- SCIE、EI、Scopus
- 文献类型:
- J
- 卷号:
- 49
- 期号:
- 2
- 页面范围:
- 506-514
- ISSN号:
- 0888-5885
- 摘要:
- Ethylation of coking benzene, the product of coke oven gas, with ethanol over nanosized HZSM-5 zeolites poisoned by 2,6-dimethylpyridine has been investigated in a fixed-bed reactor. Pyridine infrared (Py-IR), amonia temperature programmed desorption (NH(3)-TPD), thermogravimetry (TG), acidity titration with a Hammett indicator, and cyclohexane and it-hexane adsorption were used to characterize the changes in acidity and porosity of the nanosized HZSM-5 zeolites poisoned by 2,6-dimethylpyridine. Conversion and product distribution depend strongly on the degree of catalyst poisoning. The acidity-activity correlation indicates that acid sites with pK(a) < -3.0 are responsible for the ethylation of coking benzene and sites with pK(a) < 2.27 are responsibly for the thiophene conversion. The remaining acid sites, which are not active for the ethylation of coking benzene over the poisoned sample, act as active centers for ethanol dehydration to ethylene. 2,6-Dimethylpyridine not only adsorbs on the strong Bronsted acid sites but blocks the zeolite channels over the poisoned sample.
- 是否译文:
- 否