Adsorption of fluoride on gas concrete materials.

In this study, gas concrete waste materials were used to remove F(-) from aqueous solutions. The influence of pH, temperature, agitation rate and gas concrete dosage on F(-) removal was investigated by conducting a series of batch adsorption experiments. In addition, the yield and mechanisms of F(-) removal were explained on the basis of the results of X-ray spectroscopy and images of scanning electron microscopy (SEM) of the particles before and after adsorption. The values of zeta potential and BET-N(2) specific surface area of gas concrete particles were defined. In this study, F(-) removal in excess of 96% was obtained. It was thought that the removal of fluoride by gas concrete took place both adsorption and precipitation of Al(3+) and Ca(2+) salts (F(-)). As a result of this study, it was concluded that wastes of gas concrete were an efficient adsorbent for the removal of F(-).