固体碱催化剂(K_2O/C)的制备及其催化酯交换反应

Preparation of solid base of K_2O/C and transesterification catalyzed by the catalyst

以活性炭为载体,负载K2CO3后经过煅烧,制得K2O/C固体碱催化剂,通过正交实验,得到催化剂的优化制备条件为:K2CO3与活性炭摩尔比0.04,粒径40目,煅烧温度450℃,煅烧时间3.5h,浸渍时间3h;将其应用于催化棉籽油酯交换制备生物柴油,考察了催化剂的加入量、醇油比、反应温度、反应时间、原料中水分含量等对酯交换反应的影响,得到最佳工艺参数:醇油摩尔比8∶1、催化剂加入量4.0%、反应时间1h。在此条件下,K2O/C的催化活性优于传统均相催化剂,重复使用多次仍具有较好的催化效果。

A novel method was developed for the preparation of biodiesel by transesterification of cottonseed oil and methanol using solid base catalyst, K2O/C. The optimal preparation conditions of catalyst were confirmed by orthogonal experiment. The results were K2CO3/C molar ratio of 0.04, diameter of 40 mesh, catalyst calcining temperature of 450℃ ,catalyst calcining time of 3.5h and impregnating time of 3h. The transesterification of cottonseed oil was catalyzed by the catalyst, and the effects of catalyst dosage, proportion of methanol and oil, reaction time and content of water in oil on the transesterification were studied. The optimal conditions of transesterification were methanol/oil molar ratio of 8：1 ,catalyst dosage of 4.0% ,reaction time of lh. The results showed that catalytic activity of K2O/C were better than that of NaOH under the optimum conditions, and this catalyst also showed steady catalytic activity.