Equilibrium, kinetic and thermodynamic studies on biosorption of Pb(II) and Cd(II) from aqueous solution by fungus (Trametes versicolor) biomass Munagapati Venkata Subbaiah, Gutha Yuvaraja, Yarramuthi Vijaya, Abburi Krishnaiah * Biopolymers and Thermophysical Laboratories, Department of Chemistry, Sri Venkateswara University, Tirupati 517 502, A.P., India 1. Introduction Heavy metal pollution has become one of the most serious environmental problems today. Unlike organic pollutants, heavy metals are non-biodegradable and so the removal of them is extremely important in terms of health of livings specimens. Lead poisoning in human causes severe damage to kidney, nervous system, reproductive system, liver and brain [1]. Different industrial processes, such as battery manufacturing, printing and pigment, metal plating and finishing, ammunition, soldering material, ceramic and glass industries, iron and steel manufactur- ing units are major sources of lead contamination in waste water [2,30]. Cadmium is also a dangerous pollutant that is released into aquatic medium from metal plating, metallurgical alloying, mining, ceramics and other industrial operations [3,4]. Cadmium toxicity may be observed by a variety of syndromes and effects including renal dysfunction, hypertension, hepatic injury, lung damage and teratogenic effects [3,4]. The most widely used methods for removing heavy metals from wastewaters include ion-exchange, chemical precipitation, reverse osmosis, evaporation, membrane filtration, adsorption and biolog- ical treatment [5]. Most of these methods suffer from some drawbacks, such as high capital and operational cost, the disposal of the residual metal sludge, and un-suitable for small scale industries [6]. Biosorption plays an important role in the elimination of metal ions from aqueous solutions in water pollution control [7,8]. The main advantages of this technique are the reusability of biomaterial, low operating cost, improved selectivity for specific metals of interest, removal of heavy metals from effluent irrespective of toxicity, short operation time, and no production of secondary compounds which might be toxic [9]. Fungal cell walls mainly consisting of polysaccharides, proteins and lipids with many functional groups that are responsible for the binding of metals [10–12]. Several fungal biosorbents such as Penicillium [13], Trametes versicolor [31], Lentinus sajor-caju [14], Rhizopus arrhizus [32], Rhizopus oryzae and Aspergillus oryzae [15], and Aspergillu niger and Mucor rouxii [16] have been used for the removal of heavy metal from aqueous solution. T. versicolor is a basidiomycete fungus and has many functional groups responsible for the biosorption of heavy metals. The biosorbent material has proved to be both economic and eco friendly as it is available abundantly regeneration with potential for and high surface area to volume ratio. It provides a cost effective solution for industrial and natural water management. The new material was chosen as biosorbent in this study as it is natural, easily available, and thus a low-cost biomass for dissolved metal ions. The present work is focused on the potential use of T. versicolor biomass for removal of Pb(II) and Cd(II) ions from aqueous solution. Experimental parameters affecting the biosorption process such as pH, contact time, biomass dosage, initial metal ion concentration and temperature were studied. The biosorption kinetic data were analysed interms of pseudo-first-order, pseudo- second-order and intraparticle diffusion models. In addition thermodynamic parameters such as DG8, DH8 and DS8 for biosorption process was evaluated. Journal of the Taiwan Institute of Chemical Engineers 42 (2011) 965–971 A R T I C L E I N F O Article history: Received 13 December 2010 Received in revised form 23 March 2011 Accepted 5 April 2011 Available online 13 May 2011 Keywords: Biosorption Trametes versicolor Kinetics Isotherm Thermodynamics A B S T R A C T The biosorption characteristics of Pb(II) and Cd(II) ions from aqueous solution using the fungus (Trametes versicolor) biomass were investigated as a function of pH, biomass dosage, contact time, initial metal ion concentration and temperature. Langmuir and Freundlich models were applied to describe the biosorption of the metal ions by fungus (T. versicolor) biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The monolayer biosorption capacity of T. versicolor biomass for Pb(II) and Cd(II) ions was found to be 208.3 mg g 1 and 166.6 mg g 1 , respectively. The calculated thermodynamic parameters (DG8, DH8 and DS8) showed that the biosorption of both metal ions was feasible, spontaneous and endothermic at 303–323 K. Experimental data were also used to study biosorption kinetics using pseudo-first-order, pseudo-second-order and intraparticle diffusion kinetic models. The results showed that the biosorption processes of both metal ions followed well pseudo- second-order kinetics. ß 2011 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved. * Corresponding author. Tel.: +91 9393621986. E-mail address: abburikrishnaiah@gmail.com (A. Krishnaiah). Contents lists available at ScienceDirect Journal of the Taiwan Institute of Chemical Engineers jou r nal h o mep age: w ww.els evier .co m/lo c ate/jtic e 1876-1070/$ – see front matter ß 2011 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved. doi:10.1016/j.jtice.2011.04.007