采用溶胶-凝胶法和浸渍法制备了系列SO42-/TiO2-Al2O3固体超强酸催化剂,运用XRD、NH3-TPD、FT-IR、Py-FTIR、XPS、SEM等技术手段,研究了复合催化剂材料的结构与性质,初步探讨了固体超强酸SO42-/TiO2-Al2O3催化剂的构效关系,得到适宜的催化剂制备条件为:n(TiO2)(Al2 O3)=1:2、硫酸浸渍浓度1 mol/L、催化剂焙烧温度500℃.考察了物料物质的量比、催化剂用量、反应时间等对催化合成冰片的影响.结果表明,在物料物质的量比为1:0.4,催化剂用量为α-蒎烯质量的7%,采用程序升温方式(65℃-1 h,75℃-4 h,90℃-1 h)加热的条件下,固体超强酸SO42-/TiO2-Al2O3催化剂的催化活性最高,α-蒎烯的转化率高达100%,龙脑的收率高达59.74%,SO42-/TiO2-Al2O3固体超强酸催化剂在重复使用6次的条件下,α-蒎烯的转化率均不变,龙脑的收率下降2.99%,催化剂的重复使用性良好.%A series of sulphated Al2 O3-TiO2 mixed oxides were prepared by sol-gel and dipping process and used as catalysts in synthesis of borneol .The structure and properties of SO42 - /TiO2-Al2O3 solid superacid catalysts were characterized by XRD ,NH3-TPD ,FT-IR ,Py-FTIR ,XPS ,SEM techniques ,and relationship between the catalytic performance and the structure was explored . The optimal condition for the preparation of the catalyst was obtained as follows :n(TiO2 )(Al2O3 )= 1:2 ,concentration of impregnation 1 mol/L ,calcination temperature of the catalysts 500 ℃ .Meanwhile ,the effects of the dosage of level of catalyst , molar ratio of α-pinene to oxalic acid ,reaction time on borneol synthesis reaction was investigated .The results showed that when the dosage of level of catalyst was 6% and molar ratio of α-pinene to oxalic acid was 1:0 .4 ,by using the program temperature heating method (65 ℃-1 h ,75 ℃-4 h ,90 ℃-1 h) ,i .e .the optimized condition ,the resultant solid superacid SO42 - /TiO2-Al2O3 catalyst performed the best catalytic effect to borneol synthesis reaction ,asα-pinene was completely converted and high selectivity of borneol (58 .63% yield) was achieved . After 6 times reuse , the catalyst still maintained good performance—α-pinene conversion rate unchanged ,yield of borneol decreased by 2 .99% .
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