Study of the Chemical Stability of Solidified Radioactive Waste Using Alkali Cement Through Long-Term Leaching

Abstract:

The article presents the results of studies of the chemical stability of solidified radioactive waste with alkali cement through long-term leaching. Efficiency of application of alkaline slag Portland cement type LCEM IV as a matrix for reliable chemical and physical binding of caesium ions in the compound for long-term burial we confirmed. Modification of alkaline cement by additions of magnetite from 5 to 8.3% and zeolite in the amount from 4.2 to 5% promotes additional sorption of caesium ions in solidification products of alkaline matrix at maximum content of radioactive waste up to 17.5%. It they noted that the maximum values of sorption capacity of compounds (from 42000 to 68000 ml/g) we observed on the 14th day of the leaching process. They are characteristic for compounds containing magnetite from 5 to 8.3%, zeolite - from 4.2 to 7.5% and radioactive waste from 10 to 15%. It is shown that on the first day of leaching the highest rate (8.35E-02 g/сm²day) is characterised by compositions containing magnetite from 5 to 8.3%, zeolite from 4.2 to 5% and radioactive waste from 15 to 17.5%. At 56 days of the test, the leaching rate decreases exponentially to values of 3.45E-05 to 9.62E-06 g/сm²day. Characteristic of compounds, magnetite and zeolite up to 5% and radioactive waste 17.5%.

• Periodical: Solid State Phenomena (Volume 364)
• Pages: 113-120
• DOI: https://doi.org/10.4028/p-wEX4ES
• Online since: September 2024
• Authors: Sergii G. Guzii*
• Keywords: Alkali Cement, Chemical Stability, Compound, Distribution Coefficient, Dry Copper Ferrocyanide Radioactive Waste, Immobilization, Leaching Rate, Magnetite, Zeolite

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