利用菜籽油脱臭馏出物制备生物柴油新工艺

New process technology of producing biodiesel from rapeseed oil deodorizer distillate

以菜籽油脱臭馏出物为原料,首先以D002阳离子交换树脂作催化剂,进行酯化反应,降低原料酸值;然后以氢氧化钾作催化剂进行醇解反应来制备生物柴油的二步法新工艺路线。结果表明:D002阳离子交换树脂具有很强的催化活性,游离脂肪酸最高转化率达97.7%,连续使用4次后,催化活性仍然很高,达96%以上;碱催化过程中甘油酯的最高转化率达97.4%。产品品质大都符合美国ASTMD6751-03生物柴油标准。由此可见,先用树脂催化处理高酸值废油,然后进行碱催化制备生物柴油二步法工艺是一种切实可行的方法。

The production of biodiesel was investigated with rapeseed oil deodorizer distillate （RDOD） as raw material by two-step process. In first step D002 cation-exchange resin was used as esterification catalyst to reduce free fatty acid （FFA） of feedstock, and then followed by the base-catalyzed methanolysis with potassium hydroxide as catalyst. The results show that D002 cation-exchange resin has a high catalytic activity in esterification of FFA with methanol. The first step reduces the FFA level greatly, and the maximum FFA conversion rate reaches 97.7%. After being used 4 times, the resin catalyst remains a high catalytic activity more than 96%. The second step converts the product of the first step into biodiesel and glycerol, the maximum triglycerides （TGs） conversion rate is 97.4%. The quality of RDOD biodiesel, obtained after cation-exchange resin esterification （CRE） and base-catalyzed methanolysis （BCM） processes, is complied with American standard ASTM D6715-03. Thus the two-step process, CRE followed by BCM, is a feasible and practical method to produce biodiesel from RDOD with high acid value.