Organic Solvent Nanofiltration Membranes to Separate and Purify Fatty Acids

摘要

We recently developed a new class of organic solvent nanofiltration (OSN) membranes that can separate small organic chemicals into streams that are enriched in selected chemicals. These membranes were based on highly cross-linked polyepoxies fabricated from a mixture of amines and epoxides. By varying the amines and epoxides used to fabricate a membrane, the selectivity of the membrane in a separation was controlled. A wide variety of membranes were fabricated from diamines, diepoxides, and triepoxides and investigated in the separation of organic chemicals with molecular weights from 100 to 300 grams per mole. The separation of fatty acids including EPA, DHA, and saturated fatty acids were investigated with these membranes. The membranes allowed EPA-ethyl ether to permeate 1.4x faster than DHA-ethyl ester, and they allowed a C4 fatty acid ester to permeat 60x faster than a CI8 fatty acid ester.