S Arivoli et al Int. Journal of Engineering Research and Applications www.ijera.com ISSN : 2248-9622, Vol. 3, Issue 6, Nov-Dec 2013, pp.1321-1331 www.ijera.com 1321 | Page Equilibrium, Kinetic and Thermodynamic Study on Chromium (VI) Removal from Aqueous Solution Using Strychnos Nux- Vomica L S Arivoli 1* , V Marimuthu 1 and A R Mohamed Jahangir 1 1* Department of Chemistry, Thiru.Vi.Ka. Government Arts College Thiruvarur, Tamil Nadu, India. ABSTRACT The effective and economic removal of heavy metals from industrial effluents is one of the important issues globally. Batch adsorption experiments were carried to fix the adsorption dosage and also to find the optimum pH. A thermodynamic study was made on the adsorption of Cr (VI) ions in aqueous solution distinctly by the adsorbents such as activated Strychnos Nux-Vomica L Nano Carbon. The adsorption of Chromium (VI) ions by activated Strychnos Nux-Vomica L Nano Carbon increased when temperature was raised up to 60 o C .The thermodynamic study and kinetic models showed that the adsorption of Chromium (VI) ions by the above adsorbents were physical and Endothermic. Keywords: Chromium; activated Strychnos Nux-Vomica L Nano Carbon (ASNVL); adsorption models; equilibrium. I. Introduction With the world population set to break seven billion sometime next year, the management and use of natural resources is pushing to the forefront of world concern. With more people entering the worldwide market, an increase in products to meet their needs is inevitable. Individuals, businesses, and industries are seeing not only the long term monetary benefit of using resources wisely, but also the aesthetic and health benefits that come from environmental stewardship. This is seen from the changing of light bulbs at home to the tightening of national government and world standards for environmental quality[1]. With potable water essential to life, no where else are these standards more important than the area of water quality. Not only is water essential for life, it has become the primary workhorse of industries around the world as a working fluid, transport medium, heat transfer fluid, cleaning agent, etc. Unfortunately this has often led to the degradation of water quality as harmful effluents are returned to the environment with various contaminants from these processes [2]. One of the most startling groups of water contaminants are those of heavy metals due to their accumulation in biological systems and their toxicity even at relatively low concentrations [3]. Sources of heavy metal water contamination are varied and can be seen in every step of production from mining, purification and processing, to metal finishing and electroplating, and even end use [4]. Electroplating, the process by which metal is deposited on a surface via an electric current, has been a major contributor to water contamination by a wide variety of heavy metal ions.10 Industry currently treats electroplating wastewater via a lime-soda precipitation technique that, although effective, essentially shifts the problem to large volumes of sludge containing heavy metals [5]. Not only does this method not solve the problem of heavy metal pollution, electroplating industries also must deal with the loss of the useable metal which is becoming increasingly expensive due to a decrease in the quality of metal ores [6]. What is needed is an economical method, not only for the removal of heavy metals from waste water, but also the recovery of these metals. In the present investigation the adsorption of Chromium ion on activated carbon prepared from Strychnos nux-vomica L. by carbonization with sulphuric acid has been achieved. The kinetic and equilibrium adsorption data obtained were utilized to characterize the sample prepared [7]. The amounts and rates of adsorption of Chromium using above activated carbon from water were then measured. Three simplified kinetic models including pseudo first order, Pseudo second order equations and Elovich equations were used to describe the adsorption process. II. Materials and methods: All the reagents used for the current investigation were of GR grade from Scientific Equipment Company, Trichy, India. Stock solution (1000 mg/L) of Cr(VI) was prepared by dissolving 5.6578g of K 2 Cr 2 O 7 in double distilled water. The solution was further diluted to the required concentrations before use. Before mixing the adsorbent, the pH of each Cr (VI) solution was adjusted to the required value by 0.1 M NaOH or 0.1 M HCl solution. RESEARCH ARTICLE OPEN ACCESS