Abstract: The silica sulfonic acid(SiO2-SO3H) sold acid catalysts was prepared with chlorosulfonic acid reacting with the silica prepared in sol-gel method. The catalyst was used for the transesterification of soybean and ethanol to form biodiesel. Experiments have proved that the yield of ethyl esters reached over 95.6% under the condition: treatment of catalyst at 120 ℃, molar ratio of ethanol and oil is 6∶1, the mass fraction of catalyst in oil 5.0%, the mass fraction of heptane in oil 30.0% and refluxe time 6.0 h. The results show that the catalyst so prepared has a better adaptability than the solid bases catalysts to the acidity of raw oil.

Key words: SiO2-SO3H , Cottonseed oil , Transesterification ,  Biodiesel 

摘要： 通过溶胶—凝胶法制备二氧化硅,与氯磺酸反应形成二氧化硅-磺酸(SiO2-SO3H)固体酸催化剂,
并用于大豆油与乙醇的酯交换制备生物柴油。实验结果表明,二氧化硅—磺酸具有较高的酯交换反应活性。反应
温度120℃、反应时间6.0h、醇油物质的量比6∶1、w (催化剂)为5.0%和w (脂肪酸)为30.0%,生物柴油收率可达
95.6%。与固体碱催化剂相比,固体酸催化剂对原料的酸度有更强的适应性。

关键词: 二氧化硅—磺酸 , 棉籽油 , 酯交换 , 生物柴油