Rhodamine B Dye Adsorption onto Biochar from Olive Biomass Waste

摘要

Olive biomass waste (Olea europaea L.) is a by-product of vegetable oil extraction processing produced in ever-increasing quantities, becoming an environmental liability when not destination or treated correctly. Thus, the work aimed to study the application of olive biomass waste to preparation of adsorbent material (biochar) to rhodamine B (RhB) dye removal. For the preparation of the biochar, activation/carbonization process was used, where for chemical activation, the ZnCl2 was used as activating reagent, in the proportion of 1:2 w/w, and for the carbonization, used a heating rate of 10 °C min−1 to 600 °C for 240 min. Materials were characterized by X-ray diffraction (XRD), zeta potential (ZP), and Fourier transform infrared spectroscopy (FTIR), and its adsorption potential to remove RhB dye from aqueous media was verified, through kinetic, equilibrium, and thermodynamic study. About kinetic adsorption, the pseudo-first-order model showed satisfactorily represented. Moreover, Freundlich model was suitable to represent the adsorption equilibrium of the RhB dye. The maximum value for adsorption capacity was 263.71 mg g–1, and the adsorption process was thermodynamically spontaneous, favorable, and endothermic. Therefore, the olive biomass waste can be considered a potential adsorbent for the wastewater treatment with dyes, mainly.