催化剂浓度对花椒油酯化产物酸值的影响

Effect of Catalyst Concentration on the Acid Values of Esterified Zanthoxylum bungeanum Seed Oil

以高酸值花椒油(酸值63.562 m g.-g 1)为原料,经过酯化-碱炼两步反应降低游离脂肪酸的含量,研究了花椒油与甲醇发生酯化反应过程中,催化剂浓度对酯化产物酸值的影响。结果表明,在醇油摩尔比6∶1、反应温度60℃、搅拌速度850 r.m i-n 1时,酯化反应的最佳催化剂(浓硫酸)质量分数为2%(W/W),反应时间为150 m in,酯化油得率为92.5%,酸值降低到6.17 m g.-g 1;进一步通过N a2CO3碱炼反应,酯化产物油的酸值降至0.72 m g.g-1,可用于碱催化法合成生物柴油的原料。

Through esterification-alkali refining to reduce free fatty acid in Chinese prickly ash seed oil with high acid value（acid values. 63. 562 mg · g^-1）,the effect of concentration of catalyst （concentration sulfuric acid） on Chinese prickly ash seed oil esterification with methanol was investigated. The results showed that under 6 ： 1（moler ratio） methanol-to-oil ratio,60℃ ,850 r · min^-1, the optimal quantity of catalyst and reaction time of esterification were 2% （w/w） and 150 min ,respectively, and the yield of esterified oil was 92.5% ,acid value was reduced to 6. 17 mg KOH · g^-1. The acid values of oil could be further reduced to 0.72 mgKOH · g^-1 through refining with Na2CO3. Thus the Chinese prickly ash seed oil could be used as a feedstock to produce biodiesel fuel with alkaline catalyst through transesterification.