Perfluorinated oxygen- and sulfur-containing compounds as extractants for gold(III)

Abstract

A series of highly fluorinated compounds of the type {CF 3 (CF 2 ) 5 CH 2 CH 2 } 3 P=O, [{CF 3 (CF 2 ) 5 CH 2 CH 2 } 2 P(E) C H 2 C H 2 P ( E ) { C H 2 C H 2 ( C F 2 ) 5 C F 3 } ] a n d {CF 3 (CF 2 ) 5 CH 2 CH 2 } 2 C=E (E = O or S) have been examined for their ability to extract gold(III) from aqueous solutions. The phosphine oxides have been studied under liquid-liquid extraction conditions from water into perfluorohexane and found to give poor distribution ratios. The bidentate phosphine oxide, ketone and thioketone were studied under solidliquid extraction conditions and were substantially better with extraction of up to 80% of Au(III). In addition, the crystal structure of {CF 3 (CF 2 ) 5 CH 2 CH 2 } 3 P=O has been determined.

Fluorine–Fluorine Interactions in the Solid State: An Experimental and Theoretical Study

“…We have previously reported on the preparation and solid state structures of two compounds ( 1 and 3 ) that feature a fluorous ponytail but did not discuss in detail the supramolecular structure of these. Herein, we present the crystal structure of 2 and describe the differences in packing between these three compounds (Chart ).…”

“…Recently we reported on the use of fluorinated phenols for the extraction of Cs + and Sr 2+ from water into toluene, 23 and the use of highly fluorinated phosphine oxides, 24 Rf 3 PdO and Rf 2 P-(dO)C 2 H 4 P(dO)Rf 2 , and ketones, 25 Rf 2 CdO (Rf = {CF 3 -(CF 2 ) 5 CH 2 CH 2 }) as extractants for toxic metals, radionuclides, and precious metals. 26 During the course of these studies we have determined the solid state structures of several highly fluorinated molecules, and the supramolecular structures show numerous CÀF 3 3 3 FÀC contacts closer than the sum of the van der Waals radii (2.94 Å). This has allowed us an opportunity to examine a series of compounds that all feature the same CF 3 (CF 2 ) 5 -CH 2 CH 2 "ponytail" by both X-ray crystallography and computational chemistry.…”

“…We have an interest in the use of fluorinated compounds in applications to environmental chemistry and separation science. Recently we reported on the use of fluorinated phenols for the extraction of Cs + and Sr 2+ from water into toluene, and the use of highly fluorinated phosphine oxides, Rf 3 PO and Rf 2 P(O)C 2 H 4 P(O)Rf 2 , and ketones, Rf 2 CO (Rf = {CF 3 (CF 2 ) 5 CH 2 CH 2 }) as extractants for toxic metals, radionuclides, and precious metals . During the course of these studies we have determined the solid state structures of several highly fluorinated molecules, and the supramolecular structures show numerous C–F···F–C contacts closer than the sum of the van der Waals radii (2.94 Å).…”

The Role of a Nitro Substituent in C‐Phenylcalix[4]resorcinarenes to Enhance the Adsorption of Gold(III) Ions

“…[6,7] Conventional methods for gold(III) ions recovery are adsorption, solvent extraction, chemical precipitation, and membrane filtration. [8][9][10][11] Among these methods, the adsorption method is attractive as it is cheap, simple, and could be performed in the absence of toxic organic solvents. [12] Many adsorbents for gold(III) ions have been developed such as activated carbon, [13] polyethyleneimine, [14] montmorillonite, [15] and hybrid biosorbent.…”

Gold(III) extraction and recovery and gold(III)/copper(II) separation using micelles

“…Gold recovery from industrial waste is performed by pyrometallurgy, hydrometallurgy, bio-hydrometallurgy techniques [7,[10][11][12][13][14][15][16][17][18][19][20][21][22][23]. However, it has been recognized since long time that growing demand for safety concern requires clean and efficient procedures [16].…”