ADSORPTION TECHNIQUE FOR THE TREATMENT OF AS(V)-RICH EFFLUENTS

Unconventional adsorbents like hematite and feldspar have been employe d for the removal of AS(V) from aqueous system. The effect of importan t parameters like solute concentration, detention time, pH, temperatur e, agitation rate and particle size of the adsorbent has been addresse d. The process of uptake follows first-order kinetics and the data fit the Langmuir isotherm. Mass-transfer coefficients and diffusion coeff icients have also been determined to study the dynamics of transport. The pH of the system has been found to play a key role in the uptake. The maximum removal was found to be 100% with hematite and 97% with fe ldspar under optimum conditions at 13.35 mu mol L(-1) arsenic concentr ation. The data were subjected to multiple-regression analysis and a m odel has been developed to predict the uptake capacity of the adsorben ts under given boundary conditions.