Heavy metal remediation using zeolite synthesized from coal fly ash

Zeolite synthesis from Coal Fly Ash and its application to heavy metals remediation from water contaminated with Pb, Cu, Zn and Ni ions

Sofi Buzukashvilia, Roberto Sommervilleb, Weiqing Hua, Ozan Kökkılıça, Philippe Ouzilleaua, Neil A. Rowsonc , Kristian E. Watersa*

aDepartment of Mining and Materials Engineering, McGill University, Montreal, Quebec, Canada;

bSchool of Metallurgy and Materials, College of Engineering and Physical Sciences, University of Birmingham, Edgbaston, Birmingham, UK;

c School of Chemical Engineering, College of Engineering and Physical Sciences, University of Birmingham, Edgbaston, Birmingham, UK

*Author for Correspondence: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract: The unique properties of zeolites, such as their microporous structure and ion exchange capacity, make them a promising material for water treatment applications. This work explores the synthesis of zeolites from coal fly ash (CFA) using the Microwave Fusion and hydrothermal synthesis method and investigates their effectiveness in removing heavy metal ions, specifically Cu2+, Zn2+, Ni2+, and Pb2+, from an aqueous solution. Moreover, to overcome the challenge of extracting fine zeolite particles from treated water, a novel method using colloidal PVA solutions to bind magnetite nanoparticles to zeolite was used.

The obtained magnetic CFA zeolite was investigated for its adsorption performance and ability to be extracted from water. The experiments included the analysis of adsorption kinetics and the determination of both zeolites adsorption capacity in single and mixed ion systems. The results obtained in this study show that the zeolite synthesized from CFA has excellent adsorption properties for the investigated metal ions. Furthermore, the results suggest that the magnetic zeolite composite has great adsorption properties and can be easily separated from water using high intensity magnetic field. Various surface characterization techniques were utilized to examine the zeolite's surface before and after the adsorption of metal ions, and the results suggest an ion exchange mechanism for the studied metals.

Overall, this study further highlights the potential of CFA-synthesized zeolites for the removal of heavy metal pollutants from wastewater, and provides insights into the mechanisms underlying their adsorption behavior. Moreover, it was demonstrated that the synthesized magnetic CFA zeolite has potential for practical water treatment applications as an effective and sustainable material for the removal of heavy metal pollutants from wastewater. Further investigations are necessary to optimize the use of CFA magnetic zeolites for practical water treatment applications.

Keywords: zeolites; magnetic zeolites; coal fly ash; CFA; heavy metals; wastewater;