Comparing Fluoride Removal Kinetics of Adsorption Process from Waste Water by using Mosambi Peels (Citrus Limetta Peel )& Neem Leaves (Azadirachta Indica)

Abstract

Fluoride contamination in groundwater is a critical issue affecting millions globally, leading to health problems such as dental and skeletal fluorosis. Conventional fluoride removal methods, while effective, are often costly and inaccessible in rural and low-resource settings. This paper presents an eco-friendly and cost-effective approach for fluoride removal using neem leaves (Azadirachta indica) and mosambi peels as a natural biosorbent. Neem leaves (Azadirachta indica) and mosambi peels (Citrus limetta peel) readily available in many regions, contain active compounds capable of adsorbing fluoride ions from water. We were performed batchwise experiments for finding the best operating condition for maximum removal of fluoride at different contact times and keeping other parameters to be constant such as initial fluoride concentration, pH and adsorbent dose. For determining the suitable adsorption mechanism, we had investigated various kinetic models such as Langmuir’s Isotherm model, intraparticle diffusion model, Freundlich’s Isotherm model. The rate of adsorption of fluoride on neem leaves(Azadirachta indica) and mosambi peels (Citrus limetta peel ) have been determined by pseudo-first-order and pseudo-second-order rate models. The adsorption kinetics rate and mechanism is best described by the pseudo-second-order model and Freundlich’s model, respectively. The result obtained from the experiments show that the neem leaves (Azadirachta indica)and mosambi peels (Citrus limetta peel) have been proved to be a low-cost biosorbent for the defluoridation of the sewage wastewater and have high fluoride removal efficiency.