A Comparative Study of Different Al-Based Solid Acid Catalysts for Catalytic Dehydration of Ethanol

In this present study, the catalytic dehydration of ethanol over three different Al-based solid acid catalysts including H-beta zeolite (HBZ), modified H-beta zeolite with γ-Al2O3 (Al-HBZ) and mixed γχ phase of Al2O3 (M-Al) catalysts was investigated. The ethanol dehydration reaction was performed at temperature range of 200 to 400oC. It revealed that all catalysts exhibited higher ethanol conversion with increased temperatures. At low temperatures (ca. 200 to 250oC), diethyl ether (DEE) was obtained as a major product for all catalysts. However, with increased temperatures (ca. 300 to 400oC), ethylene was a major product. Among all catalysts, HBZ exhibited the highest ethanol conversion giving the ethylene yield of 99.4% at 400oC. This can be attributed to the largest amount of weak acid sites present in HBZ, which is related to the Brønsted acid. It should be mentioned that HBZ also rendered the highest catalytic activity for every reaction temperature. As the results, HBZ catalyst is promising to produce ethylene and DEE from ethanol, which is considered as cleaner technology.