P. Wieczorek et M. Tomaszewska, TRANSPORT OF AMINO-ACIDS THROUGH LIQUID MEMBRANES SUPPORTED ON NOVEL POLY(VINYLIDENEFLUORIDE) POROUS FLAT-SHEET MATRIX, Solvent extraction and ion exchange, 15(5), 1997, pp. 879-894
Flat-sheet membranes from poly(vinylidenefluoride) (PVDF) were prepare
d by the phase inversion process. LiCl was used as a modifying agent.
The porosity, maximum pore size and LEPW (liquid entry pressure of wat
er) were determined. Three types of these membranes were tested as a s
upport for n-decanol supported liquid membranes (SLM). Transport of ei
ght amino acids, selected to cover a wide variety of side chains, and
of phenylalanine methyl ester through n-decanol SLM were studied. The
ability of amino acids to permeates through these membranes depends on
the type of Bat-sheet PVDF used as a support. An increase in porosity
and pore size of the microporous matrix resulted in an increase of am
ino acids hydrochlorides nux. Strong dependence of amino acids transpo
rt on their structure was observed. Fluxes of amino acids with hydroph
obic side chains were similar to 100 times higher than those found for
hydrophilic amino acids. The stability for three SLMs prepared with n
-decanol immobilized in PVDF flat-sheet polymers was examined. The lif
e time varied with the type of membrane support. Membrane with small p
ores tends to have a longer life time than those with greater pore siz
e.