The purpose of this study is to identify and evaluate the extraction efficiency of 15 metal species for contaminated soils using supercritical CO2, a chelating agent (Cyanex 272), and ultrasound. The percent extraction of metal species showed in the ascending order of pure CO2 < "CO2 + Cyanex 272" < "CO2 + Cyanex 272 + ultrasound" for most of the metals with the exception of As, Cr, Sb and Se. The supercritical fluid extraction (SFE) of metal ions by pure CO 2 was confirmed to be inefficient but the supercritical CO 2 comprising Cyanex 272 showed a higher extraction rate than that of pure CO2. Ultrasound enhanced/assisted SFE (USFE) with Cyanex 272 could substantially enhance the extraction efficiency from the contaminated soils by facilitating mass transport which helps to move the solubilized metal or metalloid species into the supercritical fluid phase.
ASJC Scopus subject areas
- Physics and Astronomy(all)