Influence of structure type of Al₂O₃ on dehydration of methanol for dimethyl ether synthesis

This study focused on the effect of alumina properties on the catalytic performance in the dehydration of methanol to synthesize dimethyl ether. The catalysts (γ-Al₂O₃ and η-Al₂O ₃) were prepared from boehmite and bayerite, respectively, via calcination at various temperatures. With heat treatment, the properties of alumina have been changed significantly. Under identical reaction conditions, γ-Al₂O₃ calcined at 500 °C and η-Al ₂O₃ calcined at 600 °C showed the highest catalytic activity, because of high acid site density among the same types of alumina. Interestingly, η-Al₂O₃ showed higher catalytic activity than η-Al₂O₃, although both catalysts possess comparable acidic properties. This means the structure type of alumina is crucial to determine catalytic performance in this reaction.