Visible sequestration of Cu2+ ions using amino-functionalized cotton fiber

Abstract

In this study, an amino functionalized cotton fiber, which was used to adsorb Cu²⁺ ions via visible sequestration, was prepared and investigated. The amino-functionalized cotton fiber (named as ACF) exhibited enhanced adsorption, selectivity and distinct color response to Cu²⁺ ions in aqueous solutions. The absorbance responses of ACF to Cu²⁺ ions (named as ACF–Cu), obtained from the a fiber optic spectrometer, were monitored with different pH values and initial Cu²⁺ ion concentrations. A linear relationship between the absorbance response and the initial concentrations of Cu²⁺ ions was established and can be used for the determination of Cu²⁺ ion concentrations in aqueous solutions. Furthermore, in the interference study, ACF showed great selectivity to Cu²⁺ ions when other ions (e.g., Pb²⁺ or Zn²⁺ ions) coexisted with the Cu²⁺ ions in solution. The ability of ACF to effectively detect Cu²⁺ ions with the presence of other interfering ions in solution was of great significance.