Synthesis of chitosan functionalized magnetic carbon nanotubes for dispersive solid-phase extraction of bromocresol green

Abstract

Abstract. This study presents a new and rapid method for preconcentration, measurement, and removal of trace amounts of coloured wastewater using chitosan functionalized magnetic carbon nanotubes in aqueous samples. This method involves a two-phase system in which the donor phase contains an aqueous phase with bromocresol green, and the acceptor phase contains functionalized magnetic carbon nanotubes with chitosan. Experiments were carried out in two stages of extraction of bromocresol green from aqueous solution and desorption of bromocresol green using ethanol solvent. The samples were analysed by UV–Vis spectrophotometer. Extraction parameters were investigated such as the effect of organic solvent, pH of the donor and acceptor phases, extraction time, interference species, and volume of elution solvent. The isotherm of bromocresol green adsorption was fine described by the Langmuir model, and the adsorption capacity in the maximum was 28.49 mg g−1. The preconcentration factor and limit of detection for bromocresol green were 14.3 and 7.5 μg L−1, respectively. A linear range is observed between 0.1 and 20 mg L−1. Finally, the chitosan functionalized magnetic carbon nanotubes (Fe3O4@MWCNT-CN) exhibited a high potential for removing the bromocresol green from aqueous samples.