No abstract

Canister performance is a major issue for constructing reliable deep geological repositories for storing spent nuclear fuels, and corrosion resistance is main the factor determining canister durability. We developed a 2-D multiphysics model, which can predict both the corrosion rate and potential, for simulating copper canister corrosion in deep geological repositories. We found that canisters corroded through the long-cell action in a deep geological repository, the corrosion was quite limited, and the overall canister durability was around 1.7 million years. Our results demonstrated that copper exhibits sufficient corrosion resistance and that long-cell action-based corrosion cannot severely damage copper canisters.

The importance of extracting uranium from seawater with a green, efficient, and economical strategy has long been paid attention but still faces challenges of low uranyl concentration, high salinity, and competition with carbonate ions. Herein, we report a tunable carbon nitride nanostructure synthesized using molten salt, whose adsorption capacity and photocatalytic activity can be adjusted with the synthesis temperature. With increased synthesis temperature, the adsorption capacity and photocatalytic activity both showed a trend of an increase first and then a decrease. The carbon nitride nanostructure obtained at 550 °C (CN 550 ) exhibited the highest photocatalysis-assisted extraction ability (9.4 times higher than that of g-C 3 N 4 ) and that obtained at 600 °C (CN 600 ) showed the highest adsorption capacity of 1387.0 mg/g, which is 51 times higher than that of g-C 3 N 4 . In addition to the outstanding adsorption ability, CN 600 has a verified extraction rate of nearly 100% of uranyl carbonate with a pH of 6.0, 7.1, and 8.0 in simulated seawater.

No abstract

Canister performance is a major issue for constructing reliable deep geological repositories for storing spent nuclear fuels, and corrosion resistance is main the factor determining canister durability. We developed a 2-D multiphysics model, which can predict both the corrosion rate and potential, for simulating copper canister corrosion in deep geological repositories. We found that canisters corroded through the long-cell action in a deep geological repository, the corrosion was quite limited, and the overall canister durability was around 1.7 million years. Our results demonstrated that copper exhibits sufficient corrosion resistance and that long-cell action-based corrosion cannot severely damage copper canisters.