PREPARATION AND USE OF ALGINATE-BASED COMPOSITES WITH THE ADDITION OF GRAPHENE OXIDE FOR THE REMOVAL OF DIVALENT METAL IONS FROM AQUEOUS SOLUTIONS

Industrial wastewater contains heavy metals such as zinc, copper, lead, chromium, nickel,cadmium, arsenic, cobalt and mercury and is one of the types of sewage that negatively affectthe environment. Metal ions can be removed using various types of sorbents. An interestingsolution are polysaccharide-based sorbents. This paper presents research on the preparation anduse of granules based on 2% alginate with the addition of 2.81% graphene oxide as sorbents of thefollowing ions: Ni2+, Co2+, Cu2+, Pb2+ and Cd2+. Graphene oxide / alginate solutions, containingfrom 0.18% to 5.62% of GO, were prepared for the tests. Granules were formed by coagulatingsuccessive alginate solutions in 2.5% CaCl2 (Method 1). The possibility of introducing alginatesolutions directly into solutions containing metal ions was also tested (Method 2). As a result ofthe study, it was observed that the use of ready-made sorbent (Method 1) allows the removal of ~30% of the contamination within 30 to 60 minutes. This method turned out to be the most effectivefor removing Ni2+, Co2+ and Cu2+ ions. The use of a simplified procedure (Method 2), on the otherhand, allows the removal of all tested metal ions in amounts ranging from 5% (Cd2+) to 25% (Co2+).