The Effects of Precipitation Temperature on Performance of γ-Al2O3 Catalysts for Methanol Dehydration to Dimethyl Ether

Dimethyl ether (DME) is a clean-burning, non-toxic, potentially renewable fuel. In this study, γ-Al2O3 catalysts were prepared by a co-precipitation method and characterized by BET, XRD, NH3-TPD analysis. The effects of precipitation temperature on catalyst characterization and its catalytic performance in the methanol dehydration to DME reaction were investigated. Also, a conventional commercial γ-Al2O3 catalyst was utilized as a reference sample for comparing of catalytic activity. The performance test runs of the catalysts were conducted in an isothermal fixed-bed reactor at T= 260 oC and atmospheric pressure with methanol WHSV= 3 h-1. The result showed that increasing precipitation temperature (from 50 up to 80 oC) lead to an increase in surface area, pore volume, average pore diameter and crystal size of the catalyst and thus the catalyst performance improved. There is no close correlation between the catalytic activity and the total amount of acid sites determined by NH3-TPD. The performance of the prepared catalysts was much better than the commercial catalyst.

کلیدواژه ها:

Dimethyl ether ، Methanol dehydration ، γ-Al2O3 ، Precipitation temperature