Biosorption potential of Trichoderma gamsii biomass for removal of Cr(VI) from electroplating industrial effluent

Abstract

The potential use of acid-treated biomass of Trichoderma gamsii to remove hexavalent chromium ions from electroplating industrial effluent was evaluated. Electroplating industrial effluent contaminated with 5000mg/L of Cr(VI) ions, collected from industrial estate of Gujarat, India, was mixed with acid-treated biomass of T. gamsii at biomass dose of 10mg/mL. Effect of contact time and initial Cr(VI) ions was studied. The biosorption of Cr(VI) ions attained equilibrium at time interval of 240 minutes with maximum removal of 87 at preadjusted initial Cr(VI) concentration of 100mg/L. The biosorption of Cr(VI) ions by biomass of T. gamsii increased as the initial Cr(VI) ion concentration of the effluent was adjusted in increasing range of 100-500mg/L. At 500mg/L, initial Cr(VI) concentration, acid-treated biomass of T. gamsii showed maximum biosorption capacity of 44.8mg/g biomass from electroplating effluent. The Cr(VI) biosorption data were analysed using adsorption isotherms, that is, Freundlich and Langmuir isotherm. The correlation regression coefficients (R2) and isotherm constant values show that the biosorption process follows Freundlich isotherm (R2 ≥ 0.9, n ≥ 1, and Kf =8.3). The kinetic study shows that biosorption of Cr(VI) ions by acid-treated biomass of T. gamsii follows pseudo-second-order rate of reaction at increasing concentration of Cr(VI). In conclusion, acid-treated biomass of T. gamsii can be used as biosorbent for Cr(VI) ions removal from Cr(VI)-contaminated wastewater generated by industries. © 2012 B. Kavita and Haresh Keharia.