Radiation–Thermal Decomposition of Nitric and Acetic Acids in a Aqueous Nitrate Solution

The kinetics of radiation, thermal, and radiation–thermal decomposition of a mixture of nitric and acetic acids in water solutions of sodium nitrate is investigated under homogeneous conditions and with a solid phase introduced in the form of sandstone. The experimental data are used to calculate the temperature dependences of the rate of radiation, thermal, and radiation–thermal decomposition of the acids. The results obtained make it possible to calculate the dynamics of decomposition of acids for the conditions of deep burial of liquid radioactive wastes.     

Use of different compositions in a technological scheme for decontamination of equipment from a gas-diffusion plant

Institute of Physical Chemistry, Russian Academy of Sciences. SKhK. Translated from Atomnaya énergiya, Vol. 79, No. 1, pp. 18–22, July, 1995.     

Radiolysis Products of Nitrate-Acetate Aqueous Solutions and Their Influence on pH of the Solutions

The influence of the components of nitrate-acetate aqueous solution and products of their radiolysis on pH of the solutions was experimentally studied in a wide dose range. The results can be used to estimate the speciation and migration conditions of radionuclides in a reservoir bed of underground disposed sites of liquid radioactive waste.     

Effect of Contact Time of Liquid Radioactive Waste with Bed Rock of Underground Repository on Migration Behavior of 90Sr, 137Cs, 239Pu,and 241Am

Behavior of radionuclides caused by interaction of acidic waste with sandy bedrock in deep underground repositories is studied, including sorption-desorption of ⁹⁰Sr, ¹³⁷Cs, ²³⁹Pu, and ²⁴¹Am. The amount of mobile forms of radionuclides decreases with increasing contact time with bedrock, thus decreasing the migration rate of the radionuclides in the collector bed.     

Physicochemical Processes Occurring in Long-Term Storage of Liquid Radioactive Waste in Deep Underground Collector Beds

Interaction under hydrothermal conditions (pressure 3 MPa; temperature 80-170°C; contact time up to 2500 h) of intermediate-level acidic waste with bed rock of the underground repository for liquid radioactive waste is studied. Transformation of rock-forming minerals under these conditions is accompanied by increasing absorption of ¹³⁷Cs, ⁹⁰Sr, ²³⁹Pu, ²⁴¹Am, and ²³⁸U.