Effect of light on concomitant sequestration of Cu(II) and photodegradation of tetracycline by H-MOR/H-β/H-ZSM5 zeolites

Abstract

It is important that a pollution remediation system be able to cater for a variety of pollutant species present in the water to be treated. The aim of this study was to utilise a series of commercial zeolites (H-MOR, H-β, and H-ZSM5) for the concomitant adsorption and photodegradation of Cu²⁺ and tetracycline (TC) molecules. The adsorbent cum photocatalyst was characterised by SEM and FTIR. FTIR confirmed the key functional groups (Si-O-Si and Al-O-Si) in the series of zeolites, and H-β zeolite was demonstrated to be the most effective adsorbent cum photocatalyst for both adsorption and photodegradation of Cu²⁺ and TC molecules. These results were further corroborated from the pseudo-first-order rate constant values. Among the investigated zeolites, H-ZSM5 displayed the least adsorption and photodegradation performance for Cu²⁺ and TC molecules. The photolysis reaction confirms the significant role of zeolites in the photodegradation test, as low performance was recorded in the absence of the zeolites.

Keywords: Environmental protection; Heavy metals; Photocatalytic degradation; Tetracycline; Zeolite.