| abstract |
There is provided a process for recovering purified polyunsaturated fatty acids or derivatives thereof from mixtures containing such fatty acids and unwanted substances in which the feed is subjected to a preliminary treatment using either stationary bed chromatography, the eluent possibly being a fluid at supercritical pressure, or multistage countercurrent column fractionation in which the solvent is a fluid at supercritical pressure; and then one or more fractions containing enhanced concentrations of the fatty acids of interest recovered from the preliminary treatment are subjected to further fractionation using simulated continuous countercurrent moving bed chromatography, the eluent again possibly being a fluid at supercritical pressure, in which case the preliminary treatment may be omitted altogether. |