Research Of Supercritical Carbon Dioxide Fluid Extraction Of Strontium

Supercritical fluid extraction is a new kind of separation technology. There exist a lot of experimental data on extraction of organic compounds by carbon dioxide and experience on commercial use of CO₂ for reprocessing of natural raw materials. Supercritical carbon dioxide chelating extraction is a new way to extract metals from different media. Recent studies have demonstrated the feasibility of removing metals by chelating using a SCF-CO₂ mobile phase.During the last decades,lots of data and information regarding the metal extraction by supercritical fluid extraction have been accumulated. These data have shown the advantages of supercritical fluid extraction method, the main of which is low volume of secondary waste.In this article, Supercritical fluid chelating extraction of Sr²+ is introduced. An useful apparatus based on extraction metal inons in laboratory. On the one hand , the effects of chelants, temperature, pressure, pH, matrices, modifiers and extracted chemical species on supercritical CO₂ chelating extraction are discussed. On the other hand, The work reports for the first time in China the successful extraction of Sr²+ from aqueous media into SCF-CO₂ utilizing a macrocyclic compound and a fluorinated counter anion.Some processes for decontamination of different objects from heavy and radioactive metals are developed and tested, new scientific and technological approaches to spent nuclear fuel reprocessing from nuclear power plants are underway. Fundamental investigations on dissolving processes of metal oxides and metal complex extraction are still in the initial stage. A more broad application range is prospected with an in-depth research of supercritical carbon dioxide fluid extraction of metals.