固体超强酸SO_4^(2-)/Fe_2O_3催化制备生物柴油的研究

Preparation of biodiesel catalyzed by SO_4^(2-)/Fe_2O_3 solid super acid

采用沉淀-浸渍法制备固体超强酸SO42-/Fe2O3催化剂,并将该催化剂用于生物柴油的制备。研究了沉淀温度、焙烧温度对催化剂性能的影响,用FTIR对催化剂进行了表征。考察了催化剂用量、醇油摩尔比、反应温度、反应时间对生物柴油收率的影响。实验表明,SO42-/Fe2O3固体超强酸对制备生物柴油具有较高催化活性,冰水浴中沉淀、500℃焙烧效果最佳。SO42-/Fe2O3固体超强酸催化制备生物柴油的最佳工艺条件为:催化剂用量为原料油质量的2%,醇油摩尔比12∶1,反应温度220℃,反应时间8h。在最佳条件下,生物柴油收率可达80%以上。催化剂重复使用5次(40h),生物柴油收率仍在70%以上。

The catalyst of SO^2- 4/Fe2O3 solid super acid was prepared by deposition-dipping method, and then was used to catalyze the transesterification of rapeseed oil with methanol to produce biodiesel. The structure of catalyst was characterized by FTIR. The results showed that the optimal condition of preparing catalyst was deposition in iced water bath and calcination tem perature 500 ℃. The optimal reaction conditions of synthesizing biodiesel using SO^2- 4/Fe2O3 were as follows： the catalyst quantity 2.0% of the rapeseed oil, the molar ratio of methanol to oil 12： 1, reaction temperature 220 ℃, reaction time 8 h. The yield of biodiesel was up to 80% under the optimal conditions. The catalyst was repeatedly used for 40 h, the yield of biodiesel was yet up to 70%.