Autthanit Chaowat, Jongsomjit Bunjerd
Center of Excellence on Catalysis and Catalytic Reaction Engineering, Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University.
J Oleo Sci. 2018 Feb 1;67(2):235-243. doi: 10.5650/jos.ess17167. Epub 2018 Jan 23.
The present work deals with the catalytic performance of SBA-15 supported catalysts in the gas phase catalytic dehydration of ethanol in the temperature range of 200 to 400°C. The SBA-15 support was incorporated on a zirconium (Zr) and bimetal of zirconium and lanthanum (Zr-La) prepared by sol-gel (SG) and hydrothermal (HT) methods. The catalysts were characterized by means of N physisorption, SEM/EDX, and NH-TPD. The experimental results demonstrated that the Zr-La/SBA-15-HT exhibited the highest catalytic activity. Ethanol conversion and ethylene selectivity were found to increase with increased reaction temperature. The best catalytic results were achieved for Zr-La/SBA-15-HT indicating values of ethanol conversion and ethylene yield of ca. 84% and 80%, respectively at 400°C. The most important parameter influencing their catalytic properties appears to be the interaction between metal and support depending on different methods. The metal dispersion inside the siliceous matrix of SBA-15 has a direct influence on their surface acidity. Meanwhile, the performance of these SBA-15 supported catalysts in ethanol dehydration is also related with the alteration of surface acidity caused by the introduction of Zr and Zr-La.
本工作研究了SBA - 15负载型催化剂在200至400°C温度范围内乙醇气相催化脱水反应中的催化性能。SBA - 15载体负载了通过溶胶 - 凝胶（SG）法和水热（HT）法制备的锆（Zr）以及锆和镧的双金属（Zr - La）。采用N物理吸附、扫描电子显微镜/能谱仪（SEM/EDX）和程序升温脱附（NH - TPD）对催化剂进行了表征。实验结果表明，Zr - La/SBA - 15 - HT表现出最高的催化活性。乙醇转化率和乙烯选择性均随反应温度升高而增加。Zr - La/SBA - 15 - HT取得了最佳催化结果，在400°C时乙醇转化率和乙烯产率分别约为84%和80%。影响其催化性能的最重要参数似乎是取决于不同方法的金属与载体之间的相互作用。SBA - 15硅质基质内的金属分散度对其表面酸度有直接影响。同时，这些SBA - 15负载型催化剂在乙醇脱水反应中的性能还与引入Zr和Zr - La所导致的表面酸度变化有关。
