Fabricating modified carbon of oak fruit for adsorption of fluoride and nitrate from aqueous media: isotherm and kinetic models

Abstract

Abstract Fluoride and nitrate are one of the developed compounds that can enter water resources in different ways. The present research examines the effectiveness of activated carbon made from oak fruit to remove fluoride and nitrate from water, and then the as-synthesized adsorbent is functionalized using ammonium chloride species. The results showed that activated carbon-containing NH4Cl had the highest adsorption capacity for fluoride and nitrate pollutant. The maximum absorbing capacity is 26.00 mg/g for fluoride and 26.53 mg/g for nitrate. The results of the reaction kinetics and adsorption isotherms showed that the pseudo-second-order kinetics and Freundlich isotherm fit the data from this study better than other experimental models. Eventually, recycling the adsorbent for seven cycles to adsorb the pollutant showed no remarkable activity loss. Until now, most absorption methods have been performed to remove the pollutant concentration of 30 mg/l. In the current study, with the input pollutant concentration of 50 mg/l, it can be mentioned that the activated carbon modified from the oak fruit is a cheap, efficient, and effective adsorbent. It is considered available to remove fluoride from aqueous solutions.

Keywords

• Activated carbon
• Biosorption
• Fluoride
• Nitrate
• Oak fruit