Production of clinoptilolite nanorods by glow discharge plasma technique for heterogeneous catalytic ozonation of nalidixic acid

Abstract

This study investigates nalidixic acid degradation via heterogeneous catalytic ozonation using clinoptilolite nanorods (CNs) as a novel nanocatalyst. Natural clinoptilolite microparticles (NCMs) were treated with a glow discharge plasma technique (GDP) to generate nanostructures. SEM, EDX, XRD, FT-IR, XPS, and BET were used to elucidate the morphology, chemical composition, and the microstructural properties of the NCMs and CNs. The SEM images of the untreated and plasma-treated clinoptilolite clarified that the morphology of the NCMs was converted to nanorods using the GDP technique. The catalytic performance of the NCMs and CNs in the heterogeneous catalytic ozonation of nalidixic acid was compared. The results demonstrate that in 60 min of the process, the removal efficiency is enhanced from 60.03% in the presence of NCMs to 91.08% when using the CNs. The effects of the main operational parameters and various reactive oxygen species (ROS) scavengers on the removal efficiency of nalidixic acid were thoroughly investigated. The main degradation by-products produced in the catalytic ozonation of nalidixic acid were identified by GC-MS. The ecotoxicity of nalidixic acid and the intermediate compounds formed in the process were evaluated using the aquatic species Lemna minor (L. minor).