Desorption of Cs from vermiculite by ultrasound assisted ion exchange.

Nuclear power plant accidents typically lead to the contamination of large volumes of soils with radioactive cesium. This element is hard to desorb from soil, especially when it is bound to mica minerals, and aggressive and energy-consuming techniques are often required. In this study, we investigated the use of ultrasound with Mg cation exchange for the removal of aCs-contaminated vermiculite over a wide range of temperatures (20-200 °C).

On-line spectroscopic study of brominated flame retardant extraction in supercritical CO.

Removal of brominated flame retardants (BFRs) from polymers before disposal or recycling will alleviate negative environmental effects and ensure safe usage of recycled products. Extraction of BFRs in supercritical CO is appealing but also presents challenges to industries due to limited solubility and lack of kinetic studies. For a more comprehensive evaluation of supercritical extraction potentialities, we (i) developed an on-line pressure apparatus that is compatible with both the FTIR and UV-vis spectrometers to enable kinetic and thermodynamic studies; (ii) studied kinetic extraction involving three conventional and two novel BFRs as well as three typical polymeric matrix.

Remediation of Cs-contaminated concrete rubble by supercritical CO extraction.

The removal of cesium contamination is a critical issue for the recycling of concrete rubble in most decommissioning operations. The high solvent strength and diffusivity of supercritical CO make it an attractive choice as vector for extractant system in this context. Experimental extraction runs have been carried out in a radioactive environment on rubble contaminated with Cs.