Nickel Phytoextraction from Wastewater Using Eichhornia crassipes and Oedogonium sp.: A Sustainable Approach for Helianthus annuus Irrigation

The discharge of nickel (Ni)-laden wastewater from the cooking oil industry poses significant environmental hazards. This study explores the potential of Eichhornia crassipes and Oedogonium sp. for Ni removal from industrial effluents. A 21-day phytoremediation experiment was conducted using wastewater dilutions with rainwater in ratio of 0%, 50% and 100% along with control, which were then treated individually and with a combination of Eichhornia and Oedogonium. The results showed substantial reductions in biochemical oxygen demand (BOD) and chemical oxygen demand (COD) by 49% and 69%, respectively. Notably, Ni concentration decreased by 81% in combined treatments, with the treated effluent meeting safety standards for agricultural reuse. It was then applied on germinating sunflowers for a period of three months and the Ni bioaccumulation and translocation factor was determined. The findings of this study demonstrate the efficacy of E. crassipes and Oedogonium sp. in Ni removal, offering a sustainable and eco-friendly solution for industrial wastewater treatment.