复合固体酸SnO_2-Al_2O_3催化合成柠檬酸酯的研究

Study on Catalytic Sythesis of Citrate with SnO_2 - Al_2O_3 as Complex Solid Acid

将SnO_2-Al_2O_3复合固体酸催化剂用于催化合成柠檬酸酯,对催化剂制备和酯化反应条件进行了研究。结果表明,SnO_2-Al_2O_3复合固体酸催化剂具有良好的耐水、重复使用和再生性能,催化剂最佳制备条件为:Sn/Al摩尔比1:3,焙烧温度650℃,焙烧时间3 h;催化合成柠檬酸异辛酯的最佳条件为:催化剂用量1.2％(以酸醇总量计),酸酶摩尔比1:5,反应时间2 h,柠檬酸的酯化率99.4％。

The complex solid acid catalyst Sn02 - Al2O3 was used in synthesis of citrate, wherein the conditions of catalyst preparation and esterification were respectively examined. The result showed that the catalyst had good water resistance and could be repeatedly used and regenerated. The optimum conditions were determined as follows: molar ratio of Sn/Al 1 : 3, calcining temperature 650 ℃, and calcining time 3 h for catalyst preparation, and amount of catalyst 1.2% (based on the total mass of acid and alcohol) , molar ratio of acid/alcohol 1:5, and reation time 2 h for esterification. Under such conditions the esterification of citrate was up to 99.4 % .