Adsorption of Remazol Brilliant Violet-5R from Aqueous Solution Using Sugarcane Bagasse as Biosorbent: Kinetic and Thermodynamic Studies

Abstract

Sugarcane bagasse is an inexpensive and eco-friendly natural biosorbent for the removal of various organic pollutants. The adsorption of Remazol Brilliant Violet-5R (RBV-5R) dye on sugarcane bagasse (SCB) was studied. Biosorbent was characterized using EDX and FTIR. The effect of various experimental parameters, such as pH, biosorbent dosage, initial dye concentration, contact time, adsorption with shaking and without shaking, and the temperature, was optimized. At pH 6, maximum biosorption of 92.22% was achieved using 0.15 g of SCB. The equilibrium was attained within 30–40 min for the removal of RBV-5R. The initial dye concentration of 10 µg/mL was determined as an optimum concentration for maximum removal of RBV-5R at 30 °C. Langmuir and Freundlich adsorption isotherms were applied, and it was found that the biosorption of RBV-5R follows Freundlich adsorption isotherms. Kinetic studies were also carried out and it was found that the proposed method followed the pseudo-second-order kinetic model (R2 = 0.98). From desorption study, it was found that maximum desorption in the increasing order was obtained using ethanol, methanol, and 0.2 M sodium hydroxide (NaOH). The biosorption study was applied to actual textile waste effluent to pave way for the practical usage of this technology on a larger scale and the results were found effective.