Design of high efficiency chelate fibers with an amine group to remove heavy metal ions and pH-related FT-IR analysis

Abstract

We have been searching a new ion exchange material in the form of a fiber which could get large advantages over the conventional bead type. In this approach, an effective chelating fiber is prepared by the coupling of polyacrylonitrile (PAN) and ethylenediamine. A synthesized ion exchange fiber (poly(acrylo-amidino ethylene amine), PAEA) achieved 7.8 mequiv/g of adsorption capacity in a batch test. The coupling process and capacity were confirmed through FT-IR, acid-base neutralization titration, ICP, IC, and AAS. By means of verifying the bonding peaks (hydrogen and ionic bonding) under several pHs, molecular bonding between PAEA and ions (Cu2+ and CrO42-) was certified. Surface morphologies of chelating fibers and also after metal ion adsorption were examined by AFM. Compared with a batch test, the adsorption ability was low due to the diffusion path of ions in the dynamic test.