Evolution of resistance to permeation during micellar enhanced ultrafiltration of phenol and 4-nitrophenol

This paper studies the effect of the pollutant and the presence of salts on permeation during micellar enhanced ultrafiltration (MEUF). The study case s are separation of phenol and 4-nitrophenol by means of hexadecyltrimethyl -amonium bromide, (CTAB) sodium dodecylsulfate (SDS), alkylpolyglucoside (A PG) and oxyethylated methyl dodecanoate (OMD), from water and NaHCO3 soluti ons. The approach is to evaluate the resistance of the secondary layer and its change as a function of flux, time, and the effect of pollutants and mo difiers. The effect of the presence of salt is to reduce the resistance to permeation of the membrane in the presence of APG and CTAB. Separation of n itrophenol generally takes place with higher permeation rates, but the comb ination of pollutant and salt may cause a shift in the relative permeation rates of APG and CTAB solutions. It is shown that the secondary resistance of SDS, in the presence of NaHCO3, increases proportionally to time. (C) 20 01 Elsevier Science B.V. All rights reserved.