METHOD FOR PREPARING HIGH PURITY UNSATURATED FATTY ACIDS METHYL ESTER FROM PALM OIL OR WASTE ANIMAL OIL

摘要

The present invention relates to a method for preparing high-purity unsaturated fatty acid methyl esters, including: introducing a GMS- or SPAN-based emulsifier and methanol or ethanol to fatty acid methyl esters derived from palm oil or waste animal fat and oil resources, carrying out cooling and centrifugal separation to reduce saturated fatty acid methyl esters, introducing methanol and 1,2-dichloroethane (or dichloromethane) thereto to provide a mixture at room temperature, and carrying out an aqueous urea dropping crystallization process by introducing hot aqueous urea solution dropwise to the mixture. When using the method, it is possible to recycle palm oil or waste oil and fat resources, which are not used frequently in South-East Asia, unlike the conventional method for separating unsaturated fatty acid methyl esters. In addition, the method reduces waste water generation and heat energy consumption, and needs a short reaction time to provide a raw material required for preparing dimeric acid methyl esters.