废大豆油制备生物柴油工艺路线及研究

摘要

[Objective] To reduce production cost and seek for new bio-diesel production technique. [Method] With waste soybean oil as raw material, lipase was used to hydrolyzed soybean oil, which made acid value reached (160 ±5)mgKOH/g; then, with soybean oil fatty acid as raw material, sulphuric acid as activator, bio-diesel was prepared by two-steps esterification method. [Result] The results showed that, in the first step, the mass fraction of methanol esterification is 80% , the mass percentage of strong sulfuric acid is 0.7% , reaction temperature (338 ± 2 ) K; in the second step, the flow rate through the methanol is 1.1 ml/min and the response temperature of ( 335 ± 5 ) K, the highest conversion rate of soybean oil fatty acid methyl ester is 99.52%. [ Conclusion ] The study can provide scientific theoretical basis for using new raw material and pathway in preparation of bio-diesel.%[目的]为降低生产成本,寻找新的生物柴油生产工艺.[方法]以废大豆油为原料,先用脂肪酶水解大豆油,使其酸值达到(160±5) mgKOH/g油；然后以大豆油脂肪酸为原料,硫酸为催化剂,采用两步酯化法制备生物柴油.研究两步酯化法过程中浓硫酸用量、甲醇用量及流速对酯化率的影响.[结果]试验得出,第1步酯化甲醇的质量分数为80％,浓硫酸的质量百分数为0.7％,反应温度为(338±2)K；第2步循环酯化通入甲醇的流速为1.1 ml/min,反应温度为(375±5)K,大豆油脂肪酸甲酯化的转化率达到最高,为99.52％.[结论]研究可为制备生物柴油使用新的原料和途径提供科学的理论依据.