Advanced remediation of uranium-contaminated soil

Area of Science:

• Environmental Science
• Chemical Engineering
• Nuclear Chemistry

Background:

• Existing electrokinetic decontamination for uranium-contaminated soil is energy-intensive and time-consuming.
• Acidic washing followed by electrokinetic treatment presents inefficiencies.

Purpose of the Study:

• To develop a more efficient method for decontaminating uranium-polluted soil.
• To reduce the energy consumption and time required for soil decontamination.

Main Methods:

• Soil washing with sulfuric acid and an oxidant at 65°C.
• Removal of fine soil particles using a 100-mesh sieve.
• Selective uranium adsorption using a cation exchanger (S-950 resin).
• Uranium desorption using a sodium carbonate solution.

Main Results:

• Sieving effectively reduces radioactivity in coarse soil to clearance levels.
• Electrokinetic treatment is only necessary for a small fraction of fine soil.
• Cation exchange resin S-950 unexpectedly showed high uranium adsorption (>90%).
• Uranium desorption from S-950 resin was achieved with 0.5 M Na2CO3 at 60°C (87% desorption).

Conclusions:

• A combined method of soil washing, sieving, and cation exchange significantly improves uranium decontamination efficiency.
• This approach reduces the need for extensive electrokinetic treatment, saving time and energy.
• Cation exchange offers a selective and effective method for uranium recovery from washing solutions.