X-ray photoemission investigation of binding sites in polymer-bound thiacrowns used for environmental remediation of Hg in aqueous solutions

X-ray photoemission spectroscopy has been used to examine how Hg is bound t o a polymer-bound thiacrown shown to be effective in extracting Hg-II from acidic aqueous solutions. High resolution Hg 4f and S 2p core-level spectra were acquired for a set of well-characterized sulfur-containing model comp ounds and their corresponding Hg complexes. Results from these materials we re used to interpret the Hg 4f and S 2p core-level spectra of the polymer-b ound thiacrown material, the thiacrown monomeric precursors and the Hg-cont aining reacted polymer. The thiacrown structure was found to be unaffected by incorporation into the polymer and Hg appears to be bound to the polymer complex in a similar manner as tig is bound in monomeric thiacrowns contai ning five sulfur atoms. (C) 2000 Elsevier Science B.V. All rights reserved.