Catalysts prepared for ethanol dehydration in a fixed-bed reactor acted as strong active acidic catalysts under reaction conditions at lower temperatures. Experimental conditions including the catalyst type [active aluminum oxide (γ-Al2O3) and ZSM-5 zeolite catalyst modified using two-stage through dealumination or desilication and by using the impregnation method with phosphorous and lanthanum], weight hourly space velocity (WHSV), ethanol concentration, and reaction temperature were investigated to obtain optimal reaction conditions. The catalysts were characterized using the Brunauer–Emmett–Teller method, temperature-programmed desorption of ammonia gas, thermogravimetric analysis, X-ray photoelectron spectroscopy, and X-ray diffraction. The results revealed that the ethylene yield and selectivity were 98.5 and 100%, respectively, for the ZSM-5 zeolite catalyst modified through dealumination at a temperature of 220 °C and WHSV of 2.5 h–1 when the ethanol concentration was 95%. The ethylene yield and selectivity were 94.3 and 94.4%, respectively,for the ZSM-5 zeolite catalyst modified using phosphorous at a temperatureof 240 °C and WHSV of 1.5 h–1 when the ethanolconcentration was 20%. Both of these catalysts were the most favorableamong all prepared catalysts.
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机译：为在固定床反应器中进行乙醇脱水而制备的催化剂在较低温度下的反应条件下充当强活性酸性催化剂。实验条件包括：催化剂类型[活性氧化铝（γ-Al2O3）和ZSM-5沸石催化剂，通过两步脱铝或硅化和磷和镧的浸渍方法改性]，重时空速（WHSV），研究乙醇浓度和反应温度以获得最佳反应条件。使用Brunauer-Emmett-Teller方法，程序升温的氨气脱附，热重分析，X射线光电子能谱和X射线衍射对催化剂进行了表征。结果表明，当温度为220°C和WHSV为2.5 h -1 时，通过脱铝改性的ZSM-5沸石催化剂的乙烯收率和选择性分别为98.5和100％。乙醇浓度为95％。乙烯的收率和选择性分别为94.3％和94.4％，温度下用磷改性的ZSM-5沸石催化剂的制备乙醇时240°C和WHSV为1.5 h –1 浓度为20％。这两种催化剂都是最有利的在所有制备的催化剂中。
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