AIST Succeeds in Extracting Cesium from Contaminated Soil Using Low-Level Acid

Japan's National Institute of Advanced Industrial Science and Technology (AIST) announced on August 31, 2011, that it had developed a technology to extract cesium from contaminated soil into low-level acid aqueous solution. The accident at Tokyo Electric Power Company's Fukushima Daiichi Nuclear Power Plant following the Great East Japan Earthquake on March 11, 2011, caused widespread soil contamination. Treatment of the contaminated soil is a crucial issue Japan is currently facing. A cesium-extracting technology that uses high-level acid is well known but also has its problems, such as material-handing difficulties and high costs.

The new technology uses a lower weight ratio of acid solution to soil and carries out the process at a higher temperature--200 degrees Celsius--to ionize most of the cesium into a low-concentration acid aqueous solution. In addition, AIST also succeeded in separating the extracted cesium ions using a nanoparticle-absorbent that uses Prussian blue, a synthetic pigment. It is expected that the combination of extracting and separating cesium from soil will contribute to a reduction in the total amount of radioactive waste.

AIST intends to improve the technology by optimizing processing temperatures and acid concentrations and reducing the amount of Prussian blue that it uses. It will also call on other entities to collaborate in conducting verification tests and then investigate how to utilize the technology to decontaminate other materials such as sludge and incinerator ash.

Posted: 2011/12/18 06:00:15 AM