Investigation of the Adsorption of Mango and Pitanga Pruning Waste Biochar for the Removal of Methylene Blue

This research investigates the adsorption potential of mango and pitanga tree pruning waste biochar produced at 300 °C and 500 °C for the uptake of Methylene Blue (MB) dye. The particle size of biochar and initial MB concentration were varied. Equilibrium data was modeled using Langmuir, Freundlich and Temkin equations. It was found that the pyrolysis process and the initial dye concentration directly influence the adsorption process. Increasing the temperature of the treatment resulted in an increase in the efficiency and adsorption capacity of the material. Finer particles (< 0.25 mm) were more efficient in adsorbing MB. Both materials presented similar modeled parameters for Langmuir Freundlich and Temkin isotherm equations. The adsorption at equilibrium of MB is best described by Langmuir and Freundlich models, and the modeled maximum adsorption capacity of both materials is 19.4 mg g-1, proving its efficiency in the adsorption of MB and that the temperature of thermochemical process did not affect qm.