REMOVAL OF FLUORIDE FROM URBANE DRINKING WATER BY EGGSHELL POWDER

The aim of this applied-analytical study is to investigate feasibility of fluoride (F) removal from drinking water using batch reactor with using eggshell powder. The variables under study involve pH, contact time, adsorbent doses, initial F concentration, reaction kinetics, and eggshell powder characteristics. Sample of urban drinking water is prepared containing 3-12 mg/L F. Eggshell powder is prepared in a laboratory oven at 105˚C for 12 h. The F-containing water enters batch reactor and F removal efficiency is studied in different cases of the variables pH (4-10), contact time (0-80 min), and adsorbent doses (1-2.5 gr/dl). Characteristics of the eggshell powder show that the average diameter size of eggshell powder is 2 μm. The main component of eggshell powder is calcium carbonate (CaCO3). The best conditions for F removal are obtained to be pH 6, contact time 60 min, and adsorbent dose 3 gr, and F concentration 3 mg/L. The adsorption of F in eggshell powder is obtained from Langmuir isotherm.

کلیدواژه ها:

Adsorbent ، Calcium carbonate ، Eggshell ، Langmuir ، Urbane drinking water