FEASIBILITY OF ALGINATES AS IONIC EXCHANG ERS FOR WASTE-WATER TREATMENT - EQUILIBRIUM STUDIES

The retention or seizure of heavy metals on calcium alginate gels has some interest as an alternative technique to the treatment of trade aq ueous effluents. The preparation of these gels has been carried out in the laboratory from commercial sodium alginate. The study of metal re tention in the equilibrium has been done in a discontinuous contactor where it is fed the inmediately prepared gel. The functional group pro tonation has no effect on the metals retention in a wide pH range. It has been applied an ion exchange model that considers the metallic por tion encased in gel for the interpretation of experimental results. Ba sed on the equilibrium constants calculated, it is deduced that select ivity order is: Cu > Cd > Co > Ni, Zn.