International Journal of Innovation and Applied Studies ISSN 2028-9324 Vol. 8 No. 3 Sep. 2014, pp. 1390-1399 © 2014 Innovative Space of Scientific Research Journals http://www.ijias.issr-journals.org/ Corresponding Author: Ismail M. M. Rahman 1390 Evaluation of Moringa oleifera Carbon for the As(III) Removal from Contaminated Groundwater Suman Barua 1 , Ismail M. M. Rahman 1 , M. Nazimuddin 2 , and Hiroshi Hasegawa 3 1 Department of Applied and Environmental Chemistry, Faculty of Science, University of Chittagong, Chittagong 4331, Bangladesh 2 Department of Chemistry, Faculty of Science, University of Chittagong, Chittagong 4331, Bangladesh 3 Institute of Science and Engineering, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan Copyright © 2014 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. ABSTRACT: Removal of trivalent arsenic from contaminated groundwater was studied using steam activated carbon prepared from the leaf, seed and pod of Moringa oleifera (MO) plant of the indigenous-cultivar of Bangladesh. Batch adsorption experiments were performed as a function of contact time, adsorbent doses and variants. The removal efficiency of the MO- leaf-carbon and MO-seed-carbon was substantial, while it was trivial for MO-pod-carbon. The pseudo-first- and second-order and intra-particle diffusion equations were used to evaluate the sorption mechanism of the MO carbon options. The MO is a common plant variety of the arsenic-affected Bengal delta. Therefore, it can be exploited as a cheaper resource of carbonaceous adsorbent for the economical removal of arsenic from the water. KEYWORDS: Moringa oleifera, leaf, seed, pod, arsenic, water treatment. 1 INTRODUCTION Arsenic, a toxic trace element, have incorporated in different environmental compartments, food chains and ultimately in humans due to the geogenic arsenic contamination of the groundwater [1]. The chemical forms of arsenic species determine the corresponding toxicity of arsenic in humans. Arsenite [As(III)] and arsenate [As(V)] are the most common water-soluble As-species as existed in the natural water systems, and the trivalent species is 10 times more toxic than the pentavalent variant. The As(III) mostly exists in reducing ground waters and hydrothermal waters, while As(V) is more commonly found in surface waters and oxidizing ground waters [2]. In terms of the extent of groundwater arsenic contamination and potable water exploitation source, the most people are at risk in Bangladesh followed by West Bengal, India. Hence, an unavoidable risk causing both cancerous and non-cancerous health effects is assumable to the mentioned populations due to the exposure to high level of arsenic [3, 4], unless the groundwater-supply chain is combined with any treatment procedures. The treatment techniques available for the processing of arsenic contaminated groundwater for the end-of-the-pipe drinking water supply are several [5-8], which include the application of ion-exchange resins, membranes and adsorption onto coagulated flocs or sorptive media. Arsenic removal by low-priced adsorbents has been the most promising technique, which can be implemented within a simplistic scheme and require least maintenance or operating cost [9]. There is increasing research interest in using alternative adsorbents prepared from low-cost or of minimum economic value materials