The Effectiveness of Nano Zeolite Modified by Cationic Surfactant in the Removal of Disinfection Byproduct Precursors from Potable Water

Natural organic compounds are known as precursors in the formation of disinfection byproducts. The aim of this study was to evaluate of effect of modified cationic surfactant nano zeolite in the removal of humic acid (HA) from water. Nano zeolite (clinoptilolite) was modified by cationic surfactant solution hexadecyltrimethylammonium bromide (HDTMA-Br), in dosages of 0.5, 1, 3, 5, 7 and 10 g/l. HA, turbidity and pH were measured in the beginning and at the end of the adsorption process. According to the results of one-way analysis of variance (ANOVA), there was a significant relationship between cationic surfactant dosage and HA concentration (P < 0.001). With increasing HDTMA-Br dosage, final to primary turbidity ratio, and final to primary UV254 absorbance ratio varied. In HDTMA-Br dosages of 7 and 10 g/l maximum removal efficiency for HA were respectively 96% and 86% with minimum variations in pH and turbidity value. This study showed that modification of zeolite for removal of disinfection byproducts from aqueous solution is necessary because these compounds have negative surface charge and are unable to adsorb anions. Moreover, application of HDTMA-Br at a dosage of 7 g/l and with a pH coinciding with isoelectric point can be an optimum concentration.