MnO₂ fiber as a sorbent for radionuclides in oceanographic investigations

The paper presents the results of a study of the physical, chemical and sorption properties of a fibrous sorbent-polyacrylonitrile modified with a mixed phase of manganese oxide, in relation to the natural isotopes of radium in seawater. The paper contains methodical guidelines for synthesizing the material the most efficiency and hydromechanical stability. It is described using structural (diffractometry, IR spectroscopy) and physicochemical methods of analysis (thermal analysis, gas adsorption). The possibility of using this sorbent for the concentration of cosmogenic (⁷Be) and natural (²²⁶Ra, ²²⁸Ra, ²³⁴Th) radionuclides from seawater samples under field conditions was studied. The results of determination of the concentration of dissolved ²²⁶Ra, ²²⁸Ra, ²³⁴Th in seawater samples using this sorbent were compared with the published data. Evidence of sorption ⁷Be from seawater samples using this fiber was obtained by γ-spectrometric analysis. (author)