Affinity of Bio-adsorbents Derived from Annona Squamosa, Cassia Auriculata and Ficus Religiosa towards Chromate in Polluted Waters

Leaves, stems or barks of Annona squamosa, Cassia auriculata and Ficus religiosa are identified to have remarkable tendency of sorption towards Chromate at low pH values. Physicochemical parameters such as pH, time of equilibration and sorbent concentration have been optimized for the maximum removal of Chromate from polluted waters. More than 94.0% of Chromate extraction is noted from simulated waters in all the sorbents at optimum conditions of extraction. Common Cations even in fivefold excess, have marginal effect on the extraction. Sulphate and Phosphate are interfering while the rest of the anions of the study have almost 'nil' effect. The methodologies developed are successfully applied to samples collected from industrial effluents.