Efficient adsorption capability of banana and cassava biochar for malachite green: Removal process and mechanism exploration
Hua Deng, Ya Fen Li, Shu Qi Tao, Anyu Li, Qiu Yan Li, Le Hu
Abstract
In this study, banana biochar (BB) and cassava biochar (CB) were roasted in a tube furnace at 400℃ for 2 h, and their adsorption effects on malachite green (MG) were studied. The removal of MG with respect to the solution concentration and reaction time was also investigated. The results show that the optimal amount of biochar is 2 g/L. Studies of the adsorption kinetics and adsorption isotherms show that the pseudo-second-order kinetics can most accurately reflect the adsorption process. Freundlich model fits the experimental data well. The theoretical saturated adsorption capacities of BB and CB are 1,092.80 mg/g and 261.42 mg/g, respectively. SEM-EDS, TGA, BET, FTIR, XRD, element analysis and other characterization techniques were used to explore the adsorption mechanism. Based on the characterization results, it is speculated that the adsorption of BB and CB for MG mainly includes chemical adsorption and physical adsorption.