以γ－Ａｌ２Ｏ３为载体，用浸渍法制备的负载型杂多酸催化剂用于甲醇缩合制二甲醚；用ＩＲ研究了不同温度下催化剂的表面酸类型。结果表明，催化剂表面存在着Ｂ酸位与Ｌ酸位，甲醇的转化率及二甲醚的产率与催化剂的酸度有关；提出了杂多酸催化甲醇成醚的反应机理 The supported heteropolyacid catalyst prepared by impregnation method was used to synthesize dimethyl ether from methanol by using γ-Al2O3 as carrier. The surface acid types of catalysts at different temperatures were investigated by IR. The results showed that there were B acid sites and L acid sites on the catalyst surface. The conversion of methanol and the yield of dimethyl ether were related to the acidity of the catalyst. The reaction mechanism of heteropolyacid catalyzed by methanol to ether