بررسی عملکرد زئولیت طبیعی و اصلاح شده با سورفکتانت کاتیونی در جذب کربن آلی محلول از آب های آلوده به مواد آلی

Background and purpose: Natural Organic Matter (NOM) is precursor of disinfection by-products (DBPs) during chlorination, so removal of NOM from drinking water resources is a necessary task. Due to organophilic properties, Surfactant Modified Zeolite (SMZ) can adsorb more NOM. The aim of this study was to determine and compare the efficiency of NZ and SMZ in removal of Dissolved Organic Carbon (DOC) from water. Materials and methods: Modification of zeolite was performed using Alkyl Dimethyl Benzyl Ammonium Chloride (ADBAC) as organophilic compound. Natural zeolite was added to 10% concentration of ADBAC solutions, then, the mixture was shaken for 24 h. Modified zeolite was washed several times with distilled water. Solutions containing various concentration of natural organic matter were contacted with NZ and SMZ for 48 h. The effects of parameters such as initial DOC concentration, solution pH and adsorbent dose were examined. Measurement of dissolved organic matter was performed by TOC (Shimadzu-5000) analyzer. Results: By increasing the sorbent dose, the amount of adsorbed DOC was increased. In the natural pH condition, the amount of DOC adsorption by 20 gL-1 of NZ and SMZ was 33% and 65%, respectively. By increasing the concentration of DOC the adsorption capacity increased. The best fitted model for NZ and SMZ were Freundlich and Langmuir, respectively. Conclusion: Cationic surfactant modified zeolite could increase the adsorption of DOC from water.