Abstrait

ADSORPTION ISOTHERM STUDIES OF LEAD FROM AQUEOUS SOLUTION USING FLY ASH

V. Sridevi, M.V.V.Chandana Lakshmi Satya vani yadla

Adsorption is one of the most widely applied techniques for environmental remediation. Burning pulverized coal in thermal power plants (TPPs) generates large amounts of fly ash (FA) that must be disposed of or otherwise handled; in an environmentally sound manner. Fly ash could be used as low cost adsorbent material for waste water treatment. Experiments were designed to investigate the removal of lead ions from aqueous solution onto the fly ash have been carried out at room temperature under the batch mode. The effect of various parameters such as agitation time, adsorbent dosage and initial concentration on the extent of removal of lead has been determined. The percentage removal of Pb (II) ions was found to increase with decrease in initial concentration and increase with increase in contact time and dosage of adsorbent. The adsorption process was fast and equilibrium was achieved in about 60 min of contact. The maximum removal of lead was 90.37% obtained at the adsorbent dosage 1.5 g/L. At an optimum agitation time of 60 min, the percentage removal of lead from the aqueous solution is decreased from 91.72% to 83.52% by varying lead concentrations in the aqueous solution from 20mg/l to 140mg/l. Experimental data were analyzed by model equations such as Langmuir and Freundlich isotherms and it was found Freundlich isotherm model best fitted well the adsorption data.