Utilization of wild algae biomass as biosorbent for removal of heavy metal Zinc (Zn²⁺) from aqueous solution

Climate change has both a direct and indirect effect on surface water quality. One of them is the increase in chemical weathering which causes the release of heavy metals in aquatic sediments. The toxicity of high concentration heavy metals and the phenomenon of algal bloom also become a threat to the freshwater environment. It is known that several types of algae can live, develop, and act as a biosorption agent for various types of heavy metals. The use of algae-based biosorbent also can reduce the level of global warming from the production of commercial adsorbents such as activated carbon. Hence, the objective of this study was to determine the capability of wild algae biomass from the lake Situ Agathis Universitas Indonesia, Depok West Java as a heavy metal biosorbent by elaborating on its biosorption performance, for the benefit of the wastewater treatment and the management of algae bloom. Removal efficiency zinc improved significantly by activation treatment with thermally and base treatments on wild algae biomass. The result from the experimental laboratory showed that the zinc removal up to 92.12% in 120 min by NaOH activation method at neutral pH. The obtained results suggest that the wild algae biomass is a promising benign and low-cost material for industrial wastewater treatment.