Evaluation of Cs-137 Binding by High-Moor Peat in the European North of Russia

Abstract

The sorption properties of high-moor peat and products of its sequential disassembly were studied and the binding of Cs-137 by the test materials was evaluated. According to the results of low-temperature nitrogen adsorption, the specific surface area of pores in the test materials varied in a range from 1.48 to 5.96 m²/g, and the total pore volume varied from 0.002 to 0.009 cm³/g. The limiting adsorption of Cs-137 on the test high-moor peat ranged from 1 to 51 Bq/g, which significantly exceeded the background values of Cs‑137 activity determined in the peat deposit and indicated a high sorption capacity of high-moor peatlands with respect to anthropogenic radionuclides. For peat derivatives obtained by the sequential disassembly method, the values of limiting sorption ranged from 2 to 61 Bq/g in the test range of pH. It was revealed that the pH of the medium and the nature of a sorbent are the key factors determining the efficiency of Cs-137 sorption. It was established that the values of the limiting sorption of Cs-137 for peat and products based on it increased with pH