IOSR Journal of Applied Chemistry (IOSR-JAC) e-ISSN: 2278-5736.Volume 11, Issue 4 Ver. I (April. 2018), PP 78-88 www.iosrjournals.org DOI: 10.9790/5736-1104017888 www.iosrjournals.org 78 |Page Isotherm and Thermodynamic Analysis on the Adsorption of Rhoda mine B Dye onto Borassus flabellifer bark Nano Carbon M.Thiruchelvi 1 , M.M.Senthamilselvi 2 , B.R.Venkatraman 3 , S. Arivoli 4 , And N.Muruganantham 5 1 Department of Science, Nagammai Teacher Training Institute, Periyar Centenary Educational Complex, Tiruchirappalli, Tamil Nadu, India. 2 Office of the Regional Joint Directorate of Collegiate Education, Tiruchirappalli, Tamil Nadu, India. 3 Post Graduate and Research Department of Chemistry, Periyar E.V.R.College (Autonomous), Tiruchirappalli, Tamil Nadu, India. 4 Associate Professor, Department of Chemistry, Thiru.Vi. Ka. Government Arts College, Thiruvarur, Tamil Nadu, India. 5 Post Graduate and Research Department of Chemistry, Thanthai Hans Roever College (Autonomous), Perambalur, Tamil Nadu, India. Abstract: Application of activated Borassus flabellifer bark nano carbon (ABNC) for the removal of a Cationic dye, Rhodamine B, from aqueous solutions has been investigated. The experiments were carried out in batch mode. Effect of the parameters such as pH, initial dye concentration and temperature on the removal of the dye was studied. Equilibrium was achieved in 60 min. Maximum adsorption of dye was achieved at pH 6.6. Removal percentage was found to be dependent on the initial concentration of dye solution, and maximum removal was found to be 96% at 25 mg/L of Rhodamine B. The removal increases from 80% to 96%when the initial concentration of dye solution decreases from 125 mg/L to 25 mg/L. The equilibrium adsorption data were analyzed by Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherm models. The (Langmuir) adsorption capacity of the adsorbent is found to be 232.16 mg/g at303 K. Kinetic modeling of the process of removal was carried out and the process of removal was found to follow a pseudo second order model. The thermodynamic parameters such as change in free energy (ΔG 0 ), enthalpy (ΔH 0 ) and entropy (ΔS 0 ) were determined and the negative values of ΔG 0 indicated that the process of removal was spontaneous at all values of temperatures. Further, the values of ΔH 0 indicated the endothermic nature of the process of removal. Key words: Activated Borassus flabellifer bark nano carbon (ABNC); Rhodamine-B dye; Adsorption isotherm; Kinetics; Equilibrium models. --------------------------------------------------------------------------------------------------------------------------------------- Date of Submission: 16-04-2018 Date of acceptance: 04-05-2018 --------------------------------------------------------------------------------------------------------------------------------------- I. Introduction With the revolution in textile industries, they discharge colored effluents such as organic dyes like methylene blue and rhodamine-B to water bodies. These colored effluents have large amounts of suspended organic solids which are harmful to human beings and toxic for organisms. The removal of these dyes from wastewater has a considerable attention over the past decades to decrease their impact on the environment [1]. Several physical and chemical methods have been developed for the removal of organic dyes from industrial effluents [2]. Physical methods, mainly adsorption on various supports were recognized to be a promising and effective process to remove dyes from industrial waste water completely [3, 4]. The main advantages of adsorption are the reusability of material, low-cost, ease of operation and short time of operation. So it is necessary to develop effective adsorbents for the removal of dyes from textile effluents. Activated carbon is the most widely used adsorbent and can be prepared by physical activation in which carbonation or pyrolysis of the carbonaceous material at higher temperature (600-900ºC) in an inert atmosphere followed by thermal activation at the same temperature in the presence of oxidizing agent such as air, steam and carbon dioxide or chemical activation in which pyrolysis and activation carried out only in one step simultaneously in presence of dehydrating agent such as H 3 PO 4 , HNO 3 , KOH, NaOH , H 2 O 2 , H 2 SO 4 .Chemically activated carbon has higher yield, more surface area and better development of porous structure than that obtained by physical activation [5]. Several attempts have been made for the preparation of activated carbon from agriculture wastes. In this article, we have reported the use of natural bio materials as an alternative due to their relative abundance and their low commercial values. Borassus flabellifer bark is the most ancient plant of India. It is found throughout India, especially in Tamil Nadu, Kerala and Bengal. The aerial parts of the tree have