13C CPMAS NMR Spectroscopy as a Versatile and Quantitative Tool for Determination of Mercury Adsorption Capacity in Thiol-Functionalized Mesoporous Silica SBA-1

Abstract

13C cross-polarization magic angle spinning (CPMAS) NMR spectroscopy is demonstrated to be a valuable characterization tool for quantitative measurements of Hg2+ adsorption capacity in thiol-functionalized mesoporous silica SBA-1 (Santa Barbara Amorphous-1). This is the first report on the investigation of the spectral change in the 13C CP signals for mercaptopropyl-functionalized mesoporous materials doped with different Hg2+ concentrations. The chemical shift of the carbon atom adjacent to the thiol group is sensitive to the binding of the mercury ion, and its peak intensity can be used as a quantitative sensor for the amount of the mercury ion adsorbed. The 13C CPMAS NMR results are in good agreement with inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis.