Molecular-Scale Investigation with ESI-FT-ICR-MS on Fractionation of Dissolved Organic Matter Induced by Adsorption on Iron Oxyhydroxides

Adsorption by minerals is a common geochemical process of dissolved organic matter (DOM) which may induce fractionation of DOM at the mineral-water interface. Here, we examine the molecular fractionation of DOM induced by adsorption onto three common iron oxyhydroxides using electrospray ionization coupled with Fourier-transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR-MS). Ferrihydrite exhibited higher affinity to DOM and induced more pronounced molecular fractionation of DOM than did goethite or lepidocrocite. High molecular weight (>500 Da) compounds and compounds high in unsaturation or rich in oxygen including polycyclic aromatics, polyphenols and carboxylic compounds had higher affinity to…

• NN
  National Natural Science Foundation of China

  Awards: 21407161, 21537005
• CA
  Chinese Academy of Sciences

  Award: XDB14020202
• MO
  Ministry of Science and Technology of the People's Republic of China

  Award: 2014CB441102