FLUORIDE REMOVAL USING ACTIVATED ALUMINA: A CASE STUDY OF BHOOMA CHOTA WATER

Abstract

The adsorption of fluoride, from a fluoride, contaminated groundwater sample from the village, Bhooma Chota, District Sikar, in the State of Rajasthan, India, has been studied using alumina grade DF-101. The fluoride adsorption capacity (q1) has been fitted into the pseudo-first-order adsorption, pseudo-second-order adsorption, Elovich, and intraparticle diffusion models. It has been found that the kinetic data fits best in the pseudo-second-order rate equation giving a very high correlation coefficient (R2 = 0.991). the modeled fluoride absorption capacity (q1) has been calculated from the various equations using the constants derived from the least square regression plots. The calculated q1 values, model the experimental data very well, for the pseudo-second-order and Elovich equations, as is evident from the sum of square error calculations. Fluoride removal is through a combination of surface absorption and intraparticle diffusion. A study of the fluoride removal process with increasing dosage of activated alumina reveals that though the percentage of fluoride removal increases with activated alumina, the adsorption capacity at equilibrium decreases. The minimum dosage of activated alumina which causes the maximum percentage removal of fluoride from water, while at the same time brings forth its highest equilibrium absorption capacity has been determined.