摘要
用回流吸附法制备了负载型的12-钨磷酸(HPW/C)催化剂,研究了乙醇在HPW/C上脱水生成乙烯的催化活性。发现HPW/C具有比γ-Al_2O_3高得多的活性。并且在很大的温度和空速范围内乙烯产率都接近100％。对HPW/C的热重分析表明,乙醇脱水生成乙烯的反应不存在纯HPW具有的“假液相”作用。高真空MS-TPD的研究表明,乙醇在HPW/C上的吸附是一种弱吸附;吸附的乙醇分子发生分子内脱水和氧化反应;只有当气相中存在较多的乙醇分子时,生成乙醚的分子间脱水反应才会发生。
12-Tungstophosphoric acid on active carbon(HPW/C) prepared by reflux adsorption was found to have a higher activity for dehydration of ethanol than γ-Al_2O_3, and the ethylene yield was nearly 100％ in a wide range of temperature and space time. The TG spectra indicated that the HPW/C is not a pseudo-liquid phase catalysis model in this reaction. The results of TPD and TPRS showed that the adsorbed ethanol is dehydrated to form ethylene, and oxidized to form ethyl aldehyde, and reacted with gaseous ethanol to form ethyl ether. The mechanism of the reaction was suggested.
出处
《石油化工》
CAS
CSCD
北大核心
1991年第11期755-759,共5页
Petrochemical Technology
