Abstracto

Equilibrium Analysis for Batch Studies of Adsorption of Fluoride in Water using Activated Alumina R and D 651-X

Waheed S. Deshmukh and S. J. Attar

Fluoride is one of the accumulative toxin. The batch adsorption studies were undertaken to asses the suitability of commercial available adsorbent activated alumina. From the earlier work, it was evident that the large surface area, higher acidity and good mechanical properties are requisites for the choice of suitable adsorbent. The most promising adsorbent used for defluoridation purpose is activated alumina. Among the various types of activated alumina, the type of activated alumina chosen for present study is UCIL R and D 651-X. To test its performance for defluoridation, the static studies have aimed at investigation of rate at which adsorption occurs under the varying condition of the major parameters of adsorption, viz. pH, dose of adsorbent, rate of stirring, contact time and initial adsorbate concentration on fluoride removal efficiency were studied and optimized by batch procedure, in which mixture of known concentration of fluoride solution continuously agitated and samples were taken at appropriate times, have been used in all experiments. The optimum sorbent dose was found 3.5g/L by varying the dose of adsorbent from 0 to 5 g; equilibrium was achieved in 100 min for the optimum pH. It has been observed that the optimum pH range for adsorption is between 6 to 7, by varying pH from 2 to10 and enhanced adsorption was obtained at pH 6.5. Maximum fluoride removal was observed to be 96% at optimum conditions. Freundlich as well as Langmuir isotherms were plotted and constants of isotherms were determined.