Fluoride removal from groundwater using fish scales derived biochar

The present study describes a systematic study of fluoride removal from groundwater using fish scale biochar. An effort has been made to develop a robust and efficient low-cost biochar-based fluoride removal media. There is usually a high biological oxygen demand (BOD) associated with these wastes as well as a strong offensive odour. Fish scale derived biochar as an adsorbent, which is used in this study for the removal of fluoride from aqueous solutions. It can be considered as a novel and relatively low-cost adsorbent. Fluoride ions have a greater affinity for chitosan materials than other adsorbents. Fish scale waste, which is a readily available chitosan material with virtually no value, has been analyzed so that it may be converted into a useful adsorbent. Batch adsorption and kinetic study was done to observe the efficiency of fluoride removal using fish scales derived biochar. The influences of pH, adsorbent dose, initial fluoride concentration, agitation speed, contact time, and temperature on properties were investigated. At a pH of 4–6, a maximum sorption of 6.3 mg/g was obtained, and the fluoride removal was 96 % with a fluoride concentration of 0.6 mg/l and a absorbent dosage of 0.3 g/l. A maximum sorption of 6.3 mg/g was observed at a contact period of 2 h (120 min), with a clearance percentage of 96 %. The SEM data showed that biochar had many active sites for fluoride adsorption. These sites were clearly observed on the biochar surface following the sorption trials. Washing, drying, and grinding of fish scales were performed in accordance with FTIR and SEM characterization for fluoride removal from groundwater. The results showed that fish scales derived biochar can be successfully used as an effective adsorbent for groundwater fluoride removal.