Fluoride Removal from Aqueous Medium Using Biochar Produced from Coffee Ground

Low concentrations of fluoride (F−) in drinking water are beneficial for oral health, but the natural occurrence high F− content has been reported various groundwater sources, posing a continuous ingestion threat to humans. The utilization biochar (BC) produced from residual biomass emerged as technically, economically, and environmentally sustainable alternative removal through adsorption. Therefore, this study aimed investigate physicochemical characteristics BC derived coffee grounds influence factors on adsorption process aqueous media, including pH, adsorbent dosage, contact time, temperature, initial concentration. exhibited surface area 12.94 m2·g−1 pore volume 0.0349 cm3·g−1. was strongly pH dependent, demonstrating significant decline performance increased 2.0 onwards. majority occurred within first 5 min, reaching equilibrium after 1 h testing, regardless concentration employed. data fitting Webber–Morris model indicated two-step BC, with step being external sorption second intra-articular diffusion. determined be endergonic, satisfactorily matched both Freundlich Langmuir models, qm 0.53 mg·L−1 (T = 55 °C), indicating predominance physisorption. findings suggest potential production; nevertheless, structure modifications necessary enhance affinity subsequently improve capacity.