Enhanced transport and liquid membranes in bioseparations

Emulsion liquid membranes for chiral separations: Selective extraction ofrac-phenylalanine enantiomers

“…For the extraction of polar solutes, phase transfer or ''carrier'' species are added to the liquid membrane phase to facilitate extraction and to increase the selectivity of the extraction process. Stripping of the solute from the organic phase is usually induced by a change in pH or salt concentration, 17 although other means such as photometric 20 and thermally induced 21 back-extraction have been reported. The process of liquid membrane extraction is analogous to the unit operation of solvent extraction.…”

“…A large number of separation problems have been tackled using liquid membranes: selective metal ex-traction, 15 removal of toxic components from waste water, 16 and extraction of biochemicals from fermentation broths. 17,18 Industrial scale application of liquid membrane systems has been reported for the extraction of heavy metals and organics from waste water. 19 Liquid membranes have great potential in the area of chiral separations, as described in this paper.…”

Kinetic analysis on reactive extraction of aspartic acid from water in hollow fiber membrane modules

“…However, the unreacted Asp has to be separated (or extracted) from other components in the fermentation broths or enzymatic liquors. The techniques used for separation or purification of small quantities of amino acids have been established in research laboratories including chromatography, adsorption, ion-exchange, and crystallization at the isoelectric point [1][2][3]. Nevertheless, these techniques are difficult to scale-up, which limits the levels of amino acid production.…”

Extractive separation of amino acid enantiomers with co-extractants of tartaric acid derivative and Aliquat-336

“…Amino acids can be obtained by biosynthesis or from protein hydrolysis, but their separation from fermentation broths or from protein hydrolysates is rather difficult [1][2][3]. They dissociate in the aqueous solutions, forming characteristic ionic species as a function of solution pH.…”