Eggshell-Derived Nanohydroxyapatite Adsorbent for Defluoridation of Drinking Water from Bofo of Ethiopia

Abstract EN

Fluoride has become a notable toxicological environmental hazard worldwide because it is often found in groundwater.

In the present study, hydroxyapatite adsorbent was synthesized from eggshell waste to remove fluoride from aqueous solution.

XRD, FT-IR, and TGA techniques were used to characterize the prepared adsorbent.

Batch adsorption studies were performed to examine the adsorption capacity of hydroxyapatite such as the effect of the initial pH of the solution, contact time, adsorbent dose, and initial fluoride concentration.

The fluoride ion-selective electrode was used to determine the fluoride removal efficiency.

98.8% of fluoride was removed at pH 3.0, but at pH ~7.0, 85% of fluoride was removed; it shows that the fluoride adsorption is pH dependent.

The adsorption isotherm studies (Langmuir and Freundlich models) and the experimental results for the removal of fluoride showed that the Langmuir model was more favorable and the reaction followed pseudo-second-order kinetics.

In real water samples, the prepared hydroxyapatite derived from eggshell exhibited 81% removal efficiency.

Our results indicate that eggshell waste-derived hydroxyapatite may be an alternative source for defluoridation in developing countries.