Adsorption of fluoride on gas concrete materials

In this study, as 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, (SENT) 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 Al3+ and Ca2+ 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-. (C) 2004 Elsevier B.V. All rights reserved.