Effect of humic acid on absorption-release processes in the bottom sediments-Yenisei river water system as studied by dual-column ion chromatography and γ-ray spectrometry

The effect of humic acid on absorption-release processes in the bottom sediments-Yenisei river water system was studied by dual-column ion chromatography and γ-ray spectrometry. With the use of ion chromatography, it was found that processes related to the absorption of SO42− and Cl− anions by a solid phase with the release of NO3−, PO43−, and F− to a liquid phase competed in the test systems as the concentration of water-soluble organic carbon (WSOC) was increased. Only the test anions were released in the systems without the introduction of an additional amount of WSOC as humic acid. With the use of γ-ray spectrometry, it was found that the release of 60Co, 152Eu, and 241Am radionuclides to the liquid phase in the systems with added humic acid began much earlier than in the system without the addition of humic acid. In this case, the amount of released radionuclides was greater than the amount of radioisotopes released in the system without the addition of humic acid: ∼25% 241Am, ∼3% 152Eu, and ∼0.8% 60Co in the system with added humic acid or 0.8% 152Eu and