Recent Progress in Heavy Metal Extraction by Supercritical CO₂ Fluids

Abstract

SFE-CO 2 is a novel, promising, environmentally benign and inexpensive extracting method developed over the past few years to overcome environmental problems encountered due to the use of conventional solvents. One component (the extractant) is separated from another (the matrix) using SCF-CO 2 as the extracting solvents. This method is widely used for extracting heavy metals from environmental contaminant, bioactive compounds like antioxidants, plant medicine and natural products or remediating heavy metal contaminated soil by using good binding activity of SCF-CO 2 to heavy metal ions. The major advantages of the use of SCF-CO 2 as a solvent are its superior mass transfer properties, easy recycling and lack of secondary waste formation. We try to focus on the recent advances in SCF-CO 2 extraction technology for heavy metal extraction. In this review, the mechanism, procedure, and application of heavy metal extraction by SCF-CO 2 are summarized in a comprehensive manner and the factors affecting the extraction efficiency are analyzed. We try to provide some meaningful information about heavy metal extraction by SCF-CO 2 and make it a preferable option in heavy metal treatments.

Direct extraction of palladium and silver from waste printed circuit boards powder by supercritical fluids oxidation-extraction process

“…In recent years, a more and more attention has been paid to the separation and purification of metal ions through supercritical fluid extraction (SFE) [1,2]. The potential of CO 2 as a solvent for SFE is interesting as it is nontoxic, nonflammable, abundantly available, and recyclable, minimizing the problems associated with waste liquid [3,4].…”

Synergism by β-Diketones on the Extraction of Gallium(III) with Di(2-ethylhexyl)phosphoric Acid into Heptane and Supercritical Carbon Dioxide

“…The separation and recovery of extracted substances from SC-CO 2 can be rapidly accomplished by the gasification of CO 2 . Many researchers have already reported on SC-CO 2 extraction for organic and inorganic compounds [3][4][5][6]. However, the solubility of metal complexes in SC-CO 2 is generally much lower than that in conventional organic solvents such as chloroform, dodecane, and toluene [7].…”

Recuperação De Cobre De Placas De Circuito Impresso Esgotadas a Partir De Extração Com Co2 Supercrítico

“…A utilização do dióxido de carbono (CO 2 ) vem sendo investigada, pois ele possui um ponto crítico relativamente baixo (Tc = 31,1°C, Pc = 7,38 MPa), é ambientalmente aceitável, pode ser reciclado e ser modificado com cosolventes (6 …”