采用共沸除氯工艺制备SO42-/SnO2-Nb2O5固体超强酸,该方法引入共沸蒸馏,以正丁醇和无水乙醇为溶剂,锡盐醇溶液滴加氨水前除去其中结晶水再除氯离子,免去抽滤除氯步骤,缩短了催化剂制备时间.将制备的SO42-/SnO2-Nb2O5用于催化α-蒎烯的异构化反应,考察催化剂制备条件对催化剂活性的影响,采用FT-IR,XRD,TG-DTA等对催化剂的物化性质进行表征,并与沉淀法、sol-gel法制备的催化剂进行对比.结果表明:催化剂最佳制备条件为Nb2O5加入量为SnO2质量的25％、浸渍液硫酸浓度0.5 mol/L、焙烧温度500℃、焙烧时间2h,将该条件下制备的SO42-/SnO2-Nb2O5应用于催化α-蒎烯异构化反应时,α-蒎烯完全转化,莰烯选择性为66.49％；与沉淀法、sol-gel法相比,相同条件下共沸除氯法制备的催化剂较好.%SO42-/SnO2-Nb2O5 solid superacid catalyst was prepared by azeotropic dechlorination method, using w-butanol and anhydrous alcohol as solvents, a filtration step could be omitted, and thus the catalyst preparation time was much shortened. The prepared catalyst was characterized by XRD, FT-IR, TG-DTA and its catalytic performance was evaluated using isomerization of a-pinene as probe reaction. Test results showed that the optimum preparation conditions of SO42-/SnO2-Nb2O5 solid superacid catalyst were as follows: a Nb2O5/SnO2 mass ratio of 0. 25, the concentration of impregnating sulfuric acid solution was 0. 50 mol/L and calcined at 500 ℃ for 2. 0 h; catalyst prepared under such conditions exhibited good catalytic performance in isomerization of crpinene, the conversion of α-pinene and selectivity of camphene was 100% and 66.49%, respectively. Compared with other preparation methods, such as precipitation and sol-gel methods, catalyst prepared by azeotropic dechlorination method was better.
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