APPLICATION OF FLY ASH/CHITOSAN COMPOSITES FOR HEAVY METAL ADSORPTION

Egzona Osmani, Iva Dimitrievska, Perica Paunovik, Katerina Atkovska, Fatos Rexhepi, Anita Grozdanov

Pre-print pages 1-17

DOI: https://doi.org/10.62753/ctp.2024.02.2.2

keywords: adsorption, chitosan, composites, fly ash, heavy metals, modification

abstract The aim of this paper is to investigate the potential of modified fly ash (FA) as an adsorbent for the removal of heavy metal ions from polluted waters. The effectiveness of unmodified FA was compared to FA modified with chitosan. The FA and FA/chitosan particles were characterized by means of SEM, XRF and FTIR methods. The FA and FA/chitosan composites were investigated as adsorbents for Cu (II) and Pb (II) ions from aqueous solutions. Experiments were carried out in a previously optimized pH (pH=6), at room temperature for 3 hours. Langmuir and Freundlich isotherms were used to determine the maximum adsorption capacities of the fly ash samples for Cu(II) and Pb(II) ions. The experimental data indicate that the Langmuir isotherm fits better than the Freundlich isotherm for all the investigated systems. The obtained values of the qm, maximum adsorption capacity for the removal of Cu(II) and Pb(II) with the FA/chitosan composites were (1.068, 1.00, 1.042, 1.369 mg/g), and (2.532, 2.063, 1.036, 2.146, 2.482 mg/g), respectively. The efficiency trend was Pb (II) > Cu (II). The results indicate that the removal efficiency for Cu (II) and Pb (II) ions was 91.1% and 99.7%, respectively.