A METHOD FOR DEFLUORIDATION OF GROUNDWTER TO BY THE APPLICATION OF METAL DOPED BIOPOLYMER-FLUOROFIX AS EFFECTIVE ADSORBENT

摘要

This invention describes the development of a special fluoride-removing agent named ‘Fluorofix’. At a dose of 20 gL-1 the ‘Fluorofix’ was able to reduce higher concentrations of fluoride (25 mgL-1) to below permissible limit for drinking water (1.5 mgL-1). The presence of naturally occurring ions (viz Cl-, SO42-, NO3-, PO43-, HCO3-, Ca2+, Mg2+, Fe2+ and Al3+) in ground water were studied to observe their effect in the adsorption process. Batch adsorption studies were conducted to determine the effect of particle size, contact time, dosage, pH, temperature and effects of co-ions on fluoride removal by ‘Fluorofix’. The kinetics of the adsorption and the nature of adsorption of the fluoride-biopolymer system were explained using Freundlich and Langmuir isotherm percentage of fluoride adsorption, compared to other particle sizes. The sorbent loaded with fluoride was regenerated with 0.5M NaOH solution. After alkaline regeneration the exhausted ‘fluorofix’ could be disposed of safety creating no environmental hazard due to its biodegradable nature.