Brown macro-algae as natural cation exchangers for the treatment of zinc containing wastewaters generated in the galvanizing process

In this study, brown macro-algae harvested from the north coast of Portugal, Laminaria hyperborea, Fucus spiralis, Pelvetia caniculata and Ascophyllum nodosum, were used as natural cation exchangers for the treatment of zinc-containing rinse waters generated in the galvanizing process. The zinc wastewater is characterized by a high conductivity (1.5 mS/cm), a low organic content and a zinc concentration of 10 mg/L, being approximately 80% and 20% in the form of Zn2+ and ZnSO4(aq), respectively.