EFFECT OF MINERAL SALTS ON ADSORPTION AND REGENERATION OF ACTIVATED CARBON

The successful application of activated carbon for the treatment of wastewater is very much tied to the adsorption loading and efficient regeneration of the carbon. This paper is concerned with the extent to which these steps can be improved when a mineral salt is present. A series of three-step processing sequences was carried out involving first an adsorption, then a regeneration, and finally a second adsorption. JXC 6/8 activated carbon (Carbon Products Division of Union Carbide Corporation) was used as the adsorbent for the removal of sodium benzenesulfonate from water. The salts had more effect when the salt treatment occurred simultaneously with adsorption than when salt impregnation was carried out prior to the adsorption. Calcium chloride had the greatest effect and potassium carbonate, the least. Concerning regeneration, potassium carbonate offered no improvement in adsorptive capacity after regeneration. In the cases of zinc chloride and calcium chloride, the most effective scheme was that in which impregnation was carried out simultaneously with regeneration. However, there was some improvement when the adsorption was carried in the presence of a salt. No improvement was found when the impregnation occurred prior to either regeneration or adsorption. © 1979.