生物柴油副产物甘油精制新法

Refining technology of glycerol from by-products of biodiesel

我国甘油一直供不应求,尤其是高纯度（99.5%）甘油几乎全部依靠进口.对生物副产物甘油的精制进行了研究.生物柴油反应下层液,经调pH为弱酸性（4.5～5.5）,离心分离,蒸馏去除甲醇得粗甘油;粗甘油再经活性炭脱色后以一定流速经过大孔强碱树脂和大孔弱酸树脂进行离子交换去除其中的阴阳离子,再减压蒸馏即可得无色透明、黏稠、纯度为99.6%的精制甘油.

In our country, glycerol is in lack conditions, and the glycerol with 99.5 % purity are almost based on import. A new method by using ion-exchange was researched in the refining and separation technology from byproducts of transesterification of biodiesel. Chosing macroporos resin is the novelty of this research. After stopping stirring react mixture, the by-product was added 20% H2O, then was neutralized to pH（4. 5 -5.5 ）by adding 50% H2SO4, separated by centrifugal, removed methanol, then 0. 1% activated carbon was added, stirred 20 minutes at 80 ℃ ;negative ion and positive ion were removed through strong alkali and weak acid resins, respectively, then was distilled by low pressure. Results showed that the product glycerol was colourless and dense. The purity of glycerol in the end-product was 99.6%.