Removal of Humic acid from synthetic water using chitosan as coagulant aid in electrocoagulation process for al and fe electrodes

Humic Acid (HA) is one of the polyelectrolyte compounds which cause many problems in water treatment process. The removal of this organic compound from drinking water is recommended due to its toxicity and health risks. In present study, comparative experiments were carried out using aluminium (Al) and iron (Fe) as the electrode material in Electrocoagulation Process (ECP) using chitosan as a natural coagulant aid for removing HA in synthetic water. Also, the effects of main operational parameters including pH, current density, HA initial concentration and different chitosan concentrations were investigated separately. Results indicated that the optimum conditions were obtained at pH=6, current density= 20 mA/cm2, HA initial concentration=5 mg/L and chitosan concentration=2 mg/L. Experimental results expressed that in chitosan concentration of 2.5 mg/L, the process efficiency with Al electrode was 90. Also, in the optimum condition, removal efficiency of HA were 83 and 63, for Al and Fe electrodes in ECP without chitosan respectively. Al electrode will be a better choice as compared with Fe electrode in ECP for removing HA. On the other hand, using chitosan as a coagulant aid could improve the efficiency and can be used as a convenient and costeffective coagulant aid.