固体碱催化剂MgO@SBA-15催化大豆油制备生物柴油的研究

Preparation of biodiesel by soybean oil catalyzed by MgO@SBA-15 solid base

以SBA-15分子筛为载体,采用浸渍法通过负载MgO制备了MgO@SBA-15固体碱催化剂,并对其进行了X射线衍射和N2吸附-脱附等分析表征,考察了焙烧温度、MgO负载量、醇油物质的量比和催化剂用量等因素对催化剂性能的影响。结果表明:MgO负载量为15%(质量分数)的MgO@SBA-15催化剂能够很好地保持SBA-15原有的介孔特征,且MgO在SiO2骨架上高度分散;在焙烧温度500℃、MgO负载量为15%时催化剂活性最佳;在醇油物质的量比为9∶1、催化剂用量为大豆油质量的3%、反应时间为3h的条件下,生物柴油的产率达到91.83%。

The solid base catalyst with SBA-15 molecular sieve as the carrier was prepared through loading MgO by the immersion method,and the catalyst was characterized by XRD and N2 adsorption-desorption isotherm.The results indicated that catalyst with 15%of MgO@SBA-15 could well maintain original mesoporous structure and MgO was highly dispersed on the silica skeleton.The effects of the different calcination temperature,catalyst dosage,ratio of alcohol to oil and mass ratio of catalyst to oil were investigated.The results indicated that the calcination temperature was 500℃,15%of MgO loading,the molar ratio of alcohol to oil 9∶1,and mass ratio of catalyst to oil 3%,the reaction time 3 h,the synthetically catalytic characteristics of MgO@SBA-15 was the best,and the biodiesel yield can reach up to 91.83%.