Removal of bisphenol A from water by micellar enhanced ultrafiltration with nonionic-cationic surfactant mixtures

Abstract

The removal of bisphenol A (BPA) from water with micellar enhanced ultrafiltration (MEUF) by using a mixture of nonionic oxyethylated octylphenol TX100 and cationic hexadecylpyridinium bromide (HDPBr) surfactants was studied. It was shown that formation of mixed micelles pro-motes the BPA solubilization in the hydrophobic nucleus of the micelles and provide higher BPA removal from water compared to when the single surfactants were used for MEUF process. At a total surfactant concentration of 0.24 mM, the BPA rejection values were 12%, 86% and 95%, when using HDPBr, TX100 and TX100-HDPBr mixture, respectively. The higher BPA removal with the surfactants mixture is related to a larger size of the mixed surfactant micelles. It was found that the permeate flux was also notably higher when using the surfactants mixtures obvi-ously due to formation of a more porous mixed micellar layer of lower hydrodynamic resis-tance on the membrane surface compared to the micellar layers for the singe surfactants. It was shown that the mixed TX100/HDPBr micelles are formed at lower critical micelle concentration values compared to ones for individual surfactants that reduce a total amount of the surfac-tants needed for MEUF process. Thus, employing of the surfactants mixture could improve both efficiency and cost-effectiveness of MEUF process of BPA removal from water.