氧化钙固体碱催化剂的制备及在制备生物柴油中的应用

实验研究了碳酸钙、氢氧化钙和氧化钙在催化大豆油和甲醇酯交换制备生物柴油的催化活性,并以轻质碳酸钙为原料,经过高温焙烧制备了氧化钙固体碱催化剂,考察了焙烧温度和焙烧时间对催化剂催化活性高低的影响。选取活性最高的氧化钙催化大豆油和甲醇制备生物柴油,利用气相色谱仪检测生成物中甲酯的含量来计算生物柴油的收率,结果表明:催化剂用量为大豆油质量的3.5%、醇油摩尔比为10∶1、回流时间为3.5 h,生物柴油收率可高达97.3%。通过实验进一步证明:在同一反应条件下短链醇的直链越短,支链越少,生物柴油收率越高。

Preparation of CaO solid base catalyst and its application for biodiesel synthesis

The catalytic activity of calcium carbonate, calcium hydroxide and calcium oxide used in synthesis of biodiesel by soybean oil with methanol were studied, the catalytic activity follow as: calcium oxide > calcium hydroxide > calcium carbonate. The factors of calcination temperature and time of CaO solid base catalyst prepared from light calcium carbonate were also investigated. The optimal CaO as solid base catalyst was used to catalyze soybean oil with methanol to produce biodiesel, when the reaction was carried out at a methanol/oil molar ratio of 10:1, catalyst concentration of 3.5%, reaction time of 3.5 h at reflux, the yield of biodiesel analyzed by gas chromatography was got up to 97.3%. The further experiments indicated: under the same reaction conditions, the shorter straight-chain and fewer branches of alcohol was selected to produce biodiesel, the higher yield of biodiesel was received.