Recycling of Acidic and Alkaline Solutions by Electrodialysis in a Treatment Process for Uranium Oxide Waste Using a Carbonate Solution with Hydrogen Peroxide

In this work, an electrolytic system consisting of an electro-dialyzer and a gas-absorber was devised for recycling the carbonate salt solution produced in the process that uses a carbonate-hydrogen peroxide media for treating uranium-bearing wastes. The recovery characteristics of acidic and alkaline solutions in the electrodialysis system were investigated in a batch manner by changing several variables and then evaluated in continuous operation with an electro-dialyzers stacked system. When HNO3 and NaOH solutions from the effluent solution of NaNO3 after the treatment of uranium oxide waste were recovered by the electrodialysis system, the energy consumption required to treat the same amount of feed solution decreased with decreases in the applied current and in the applied voltage, even though it took a longer time. The electrodialysis yield to recover HNO3 and NaOH was proportional to the total electricity supplied in the system, regardless of whether the constant current or constant voltage operation mode was used.