Waste cotton polyester yarn as an adsorbent for the removal of heavy metals from wastewater

Abstract

Waste cotton/polyester yarn was used for the removal of Pb(II), Cd(II), Cr(III) and As(V) ions from aqueous solution. In attempt to increase the adsorption efficiency, cotton/polyester yarn was modified by sodium hydroxide solution. Characterization of examined yarns was performed by scanning electron microscopy, Fourier transform infrared spectroscopy and streaming potential method for determination of the isoelectric point. It was shown that applied treatments slightly affected the surface acidity due to increased availability of ester groups and changes in cellulose-derived groups. These changes in surface chemistry of modified cotton/polyester yarns did not improve their adsorption capacity for Cd(II), Cr(III) and As(V) ions. However, both unmodified and modified waste cotton/polyester yarns could be used for efficient removal of lead ions from wastewater.