Comparison of different surfactant system for simultaneous removal of nitrate and phosphate using micellar-enhanced ultrafiltration

Abstract

Three kinds of surfactant systems - cationic surfactant (system 1), combinition of two cationic surfactants (system 2), and combination of two cationic surfactant and non-ionic surfactant (system 3) - for the simultaneous removal of nitrate and phosphate by micellar-enhanced ultrafiltration (MEUF) were investigated. The highest removal efficiencies of nitrate and phosphate were observed in system 2, which were 90 % of nitrate and 72 % of phosphate. The COD of permeate in system 3 was the lowest, because the added non-ionic surfactant made critical micelle concentration (CMC) lower than that of other surfactant systems. In all systems, the flux decline was similar.