HEU-type zeolitic tuff in fixed bed columns as decontaminating agent for liquid phases

摘要

The uptake of Cs, Pb, Cu, Zn, Cd, and Mn ions, from aqueous solutions by a HEU-type (clinoptilolite-heulandite) zeolitic tuff was studied in batch and column experiments. The effect of solutions concentration, time contact and flow rate on the uptake was also studied. The uptake sequence was found to be Cs>Pb>Cu>Zn>Cd>Mn. The uptake values were affected by the initial concentration and the flow rate and were inferior in column than in batch experiments. Contact time of 60 min was found sufficient in order for the maximum uptake of Cs+ to be achieved. Furthermore, the conducted experiments indicate that about 10 kg of HEU-type zeolitic tuff is able to uptake 21.4 g of Mn that corresponds to decontamination of above 1 m(3) of wastes solution with 20 ppm Mn2+ concentration. The results suggest that the HEU-type zeolitic tuff could be used as decontaminating agent in a battery of fixed bed columns.