JFET_V8_N1_RP1 Padma Sree R. D. Krishna Journal on Future Engineering and Technology 2230 – 7184 8 1 6 18 Adsorption, Batch Technique, Isotherms, Kinetics, Nonconventional Adsorbent, Ragi Husk Powder Chromium has been widely used in various industries like textile, leather, chemical manufacture, metal finishing, paint industry and many other industries. Since hexavalent chromium is a priority toxic, mutagenic and carcinogenic chemical when present in excess, it is very much required to remove chromium from effluents before allowing it to enter any water system or on to land. In the present study, the removal of hexavalent chromium by adsorption on the Ragi husk powder as adsorbent has been investigated in the batch experiments. The agitation time, the adsorbent size, adsorbent dosage, initial chromium concentration, temperature and the effect of solution pH are studied. Adsorption mechanism is found to follow Langmuir, Freundlich and Tempkin isotherms. The adsorption behavior is described by a both pseudo first order and second order kinetics. The maximum metal uptake is found to be 43.478 mg/g. The morphology on the surface of adsorbents and also the confirmation of chromium binding on adsorbent surface at different stages were obtained by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analysis. The results obtained in this study illustrate that Ragi husk powder is an effective and economically viable adsorbent for hexavalent chromium removal from industrial waste water. August - October 2012 Copyright © 2012 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=1974