Fluoride removal from water using chitosan coated activated carbon and cuttle bone carbon in combination with alumina

Abstract

Fluoride contamination of ground water is a globally important concern both in health and environmental aspect. High content of fluoride in drinking water can result in many health issues including skeletal and dental fluorosis. As there is a serious requirement for defluoridation of drinking water, activated carbon and Cuttle bone carbon was modified with chitosan (chitosan coated activated carbon – CCAC and chitosan coated Cuttle bone carbon - CCBC) and used in combination with alumina for defluoridation. Characteristics of CCAC and CCBC were studied using SEM images and FT-IR spectra. A batch adsorption study was carried out at different adsorbent dosage, contact time and initial concentration. Fluoride concentration was determined using Ion chromatography. Maximum fluoride removal efficiency of 85.37 per cent from water was obtained using a combination of 2.5 per cent chitosan coated activated carbon and 1 per cent alumina.While a maximum fluoride removal efficiency of 66.88 per cent was obtained using a combination of 2.5 per cent chitosan coated cuttle bone carbon and 1 per cent alumina. Both the combinations effected optimal fluoride removal efficiency of 94.58 and 75.63 per cent respectively at a contact time of 120 minutes. Combination of CCBC and alumina was found to be more effective with higher fluoride removal efficiency at higher initial concentration of fluoride when compared to combination of CCAC and alumina.