Application of ultrafiltration-complexation process for metal removal from pulp and paper industry wastewater

In recent years, the pulp and paper industries have been trying different technologies to reduce fresh water consumption in paper mills. This has led to a fast development of new wastewater treatment technologies for industrial reuse. Lately, water-soluble polymeric ligands have shown to be powerful substances to remove trace metals from industrial wastewater through ultrafiltration (UF). In the present study, polyethyleneimine (PEI) and polyvinylalcohol (PVA) were used as water-soluble polymeric macroligands. The UF experiments were carried out in stirred dead-end cells. The membrane used was formed from polyvinilidene fluoride (PVDF). The performance of water-soluble polymeric ligands was evaluated by determining metal removal and chemical oxygen demand (COD). In general, the complexation–ultrafiltration process was efficient for metal removal from wastewater, leading to a better effluent quality when compared to ultrafiltration without any ligands addition.