Sugarcane bagasse for the removal of erythrosin B and methylene blue from aqueous waste

Present study explores the potentiality of locally available cellulose, hemicellulose and lignin-rich agricultural by-product sugarcane bagasse (SB) for the removal of erythrosin B (EB) and methylene blue (MB) from aqueous waste. The SB has been characterized by Fourier transform infrared and scanning electron microscopy analytical techniques. Batch experiments have been carried out to determine the influence of parameters like initial dye concentration, pH of the medium, contact time between the adsorbate and adsorbent, weight of adsorbent and system temperature on the removal of EB and MB. Optimum conditions for adsorption are found to be pH 9, temperature 308 K and an equilibration time of 1 h. Under these conditions equilibrium isotherms have been analysed by Langmuir and Freundlich isotherm equations. Based on the Langmuir adsorption isotherm model, the predicted maximum monolayer adsorption capacities of SB for EB and MB are found to be 500 mg g–1 (at 328 K) and 1,000 mg g–1 (at 308 K), respectively. The separation factor reveals the favourable nature of the isotherm for the studied dyes—SB system. The thermodynamic study indicates that the adsorptions of dyes are spontaneous and endothermic process. High temperatures favour EB adsorption whereas optimum temperature for MB adsorption is 318 K