Effect of zinc ions on the removal efficiency of lead (ii) ions from wastewater using acid-modified biochar

Abstract

This paper investigates the impact of Zn ions on the adsorption performance of acid-modified biochar in removing Pb II ions from wastewater. The adsorption efficiency of biochar in a single metal ion condition was 99.99% for both Pb and Zn ions. In a multi-ion system, the adsorption efficiency for Zn ranged from 95% to 100%, whereas for Pb II ions, it was between 88% and 99%. Batch experiments were conducted to assess the influence of pH, contact time, and dose on the adsorption process. The results demonstrated that metal removal was high with pH (6.5-7), a contact time of 63 minutes, and a dose of 11-20g. Furthermore, interaction graphs were created to illustrate the combined effects of key parameters such as pH and dose, pH and contact time, and dose and contact time. The study concludes that while biochar exhibits promising potential for Pb (II) ion removal, its effectiveness may be limited in complex water systems with competing ions. These findings provide critical insights into optimizing biochar application in wastewater treatment systems for enhanced heavy metal remediation.