Low-Cost Adsorbents (Potato Peels, Banana Peels And Eggshells) For The Treatment Of Heavy Metals From Car Wash Wastewater

Abstract

Introduction: The increasing demand for car wash services has led to the discharge of large volumes of wastewater containing heavy metals such as iron (Fe), manganese (Mn), and zinc (Zn) into the public water system. These contaminants primarily originate from the gradual wear of vehicle components such as brake pads, tires, and corroded metallic parts. Such metals pose significant risks to aquatic ecosystems, human health, and environmental sustainability. Conventional treatment methods are often costly and unsustainable, highlighting the need for alternative eco-friendly approaches. Objective: This study evaluated the potential of natural waste-derived biosorbents (banana peels, potato peels, and eggshells) for the removal of heavy metals from car wash wastewater. Methodology: Wastewater samples were collected from five commercial car wash premises and analysed in the laboratory. The biosorbents were processed into three particle sizes (0.5 mm, 1.0 mm, and 2.0 mm) and applied to the wastewater samples. Heavy metal concentrations before and after treatment were determined using Atomic Absorption Spectrometry (AAS), and data were statistically analysed using one-way ANOVA. Results: Among the tested biosorbents, eggshells demonstrated the highest removal efficiencies (dosage of 2.5g/100ml, contact time of 4hrs, pH4 at room temperature), achieving 88.30% for Fe, 54.44% for Mn, and 65.52% for Zn, outperforming  Potato peels and banana peels. Conclusion: The findings underscore the potential of natural biosorbents, particularly eggshells, as cost-effective and sustainable alternatives for treating heavy metal-contaminated wastewater from car wash effluents. Adoption of such waste-derived materials may reduce reliance on conventional treatment methods while contributing to environmental protection and resource sustainability.