利用三相系統－水／離子液體／超臨界流體二氧化碳萃取金屬

Metal Extraction Using Tri-phase System-Water/Ionic Liquid/Supercritical Fluid CO_2

范芳郡(Fang-Jun Fan) ； 郎朗(Lang Lang) ； 羅俊光(Jiunn-Guang Lo) ； 瞿港華(Kong-Hwa Chiu)

《化學》 66卷1期 (2008/03) Pp. 49-59

https://doi.org/10.6623/chem.2008005

摘要

摘要：利用超臨界二氧化碳(Sc-CO_2)或室溫離子液體(RTILs)的特性，將金屬自基質中萃取移出，基本上都是利用螯合劑(有機化合物)將金屬結合後，轉變成以上這些流體能溶合的狀態而將金屬萃取，這種兩相系統的萃取(H_2O/Sc-CO_2或Sc-CO_2/RTILs)都可獲得很高的萃取效率。而一種三相系統(H_2O/RTILs/Sc-CO_2)的結合，可以提昇萃取效果，運用到部分鑭系、錒系或重金屬(如銅)的萃取，可以在不使用增效劑(synergistmoiety)以及不再需要修飾Sc-CO_2的狀況下，也可達到一樣的萃取效率，這可以使整個過程更符合綠色化學的要求，也可應用到核廢料的整治上。

關鍵字

離子液體 ； 超臨界流體二氧化碳 ； 金屬萃取

並列摘要

Using bi-phase system, i.e., H_2O/supercritical fluid CO_2 (Sc-CO_2) or room temperature ionic liquids (RTILs/)/Sc-CO_2, metal in the matrix, especial in the aqueous phase, can be extracted with high extraction under appropriate conditions. Usually, the metal forms a complex with chelating agent(s), followed by dissolved this complex in Sc-CO_2 and trapped it in organic or aqueous phase. The approach for the extraction of metal using RTILs is quite similar except the problem of separation of metal from metal-ILs is still ahead. This article describes a new tri-phase system containing H_2O, Sc-CO_2, RTILs. The combination of these three green solvents on the extraction can be applied to the separation of lanthanide or actinide elements in the matrix with high extraction efficiency. The new system can achieve the same efficiency as that in the bi-phase system without the addition of synergist moiety and modifier. This approach is greener and can be employed in the remediation of nuclear waste treatment.

並列關鍵字

ionic liquids ； supercritical fluid CO_2 ； metal extraction