A novel indigenous bioadsorbent derived from sodium carbonate-activated <i>Schleichera oleosa</i> biochar for sustainable fluoride removal

Fluoride is emerging as a menace in drinking water. It triggers dental and skeletal fluorosis and has other adverse effects on the human body. In the current study, an adsorption study was performed to remove fluoride from aqueous solution using a novel sodium carbonate treated Schleichera oleosa biochar (NC SOB) derived from indigenous biowaste Schleichera oleosa fruit peel powder, activated with sodium carbonate. To carry out the fluoride adsorption the batch experiment was conducted with variables, i.e. pH, initial concentration, temperature, adsorbent dose and contact time. Findings showed that at an initial concentration of 5 mg/L, 0.5 g dosage and at a contact period of 90 min, the fluoride adsorption efficiency peaked at 93%. The adsorption was consistent with the Freundlich isotherm model and followed the kinetics of pseudo second order. To gain insight into the adsorption mechanism characterization study, i.e. TGA, XRD, SEM- EDAX, FTIR, BET and Zeta potential were conducted. The peak adsorption potential was found to be 6.69 mg/g. Additionally, the artificial neural network model (ANN) was employed to confirm the effectiveness of the adsorption process. Indeed, the novel and sustainable biochar derived from Schleichera oleosa fruit peel powder has huge potential to remove fluoride from contaminated sources and to promote waste-to-wealth initiatives.