The molecular interaction between tetrabutylammonium iodide (TBAI) and cellulose and its potential application for the adsorption of chromium is discussed in this paper. The biosorbent was prepared under solvent free conditions using microwave irradiation. A subtle balance between electrostatic and the hydrophobic effects governs the interaction of biopolymer with the surfactant. The interaction between the biosorbent and chromium was comprehensively studied using spectroscopic, thermal and surface analysis techniques. The various analytical parameters that influence the adsorption were optimized, and the maximum adsorption capacity of Cr(VI) obtained from the Langmuir isotherm model was found to be 16.67 mg g(-1). The sorption thermodynamics indicated the spontaneity and exothermic nature of adsorption. The biosorbent could be effectively regenerated using NaOH. which imparts greener aspect to the overall process. (C) 2012 Elsevier Inc. All rights reserved.