COUPLED TRANSPORT OF AMINO-ACIDS THROUGH A SUPPORTED LIQUID MEMBRANE .1. EXPERIMENTAL OPTIMIZATION

Some experimental aspects on separation, concentration and purification of amino acids through supported liquid membranes, by using D-L-phenylalanine as a model, are described. The liquid-liquid extraction experiments, the influence on the mass-transport phenomena of various parameters (e.g. driving force, carrier concentration, diluent of the carrier, temperature) and the procedure for determining the stability of the supported liquid membranes are discussed. A significant influence of the temperature on phenylalanine (Phe) transport has been observed. It is shown that the SLM can work at 70-degrees-C without losing its transport ability for at least 150 hours without regeneration and that the value of the initial flux and the stability time depend on the carrier-diluent mixture chosen for the SLM. The experimental results have been analysed by using a model from the literature. The data obtained are consistent with that model.