Extraction of Nonionic Surfactants from Waste Water Using Centrifugal Partition Chromatography

A novel method for the extraction of nonionic surfactants from waste water is described which uses centrifugal partition chromatography (CPC). The extractant is the liquid stationary phase of the CPC apparatus, and the raffinate serves as the mobile phase. Partition coefficients (K) of nonionic surfactants were measured between water and several common organic solvents to determine the best extractant. The effect of salt concentration on K is examined. Extractions are demonstrated which remove a nonionic surfactant from a relatively large volume of simulated waste water into a relatively small volume of ethyl acetate extractant. In order to assess the viability of this method, nonylphenol ethoxylate (NPEO) was chosen because of its UV absorbance characteristics. A novel method for the extraction of nonionic surfactants from waste water is described which uses centrifugal partition chromatography (CPC). The extractant is the liquid stationary phase of the CPC apparatus, and the raffinate serves as the mobile phase. Partition coefficients (K) of nonionic surfactants were measured between water and several common organic solvents to determine the best extractant. The effect of salt concentration on K is examined. Extractions are demonstrated which remove a nonionic surfactant from a relatively large volume of simulated waste water into a relatively small volume of ethyl acetate extractant. In order to assess the viability of this method, nonylphenol ethoxylate (NPEO) was chosen because of its UV absorbance characteristics