Extraction of Gold(III) Using Cyclopentyl Methyl Ether in Hydrochloric Acid Media

Recently, cyclopentyl methyl ether (CPME) has found use as a commercially available solvent for various applications. As CPME shows better properties such as more hydrophobicity, less solublity in water, less volatility, and more stablity compared with typical ethereal solvents, it could be used as a diluent or an extractant in liquid-liquid extraction systems. In the present study, CPME was found to be useful for the extraction of Au(III) in hydrochloric acid media. Extraction of Au(III) increased with as increase in the hydrochloric acid concentration. Au(III) was selectively extracted using CPME from other precious metal ions and base metal ions. From the result of the dependency of the Au(III) concentration, CPME can load at least 0.93 g/dm3 Au(III). Extracted Au(III) was quantitatively stripped from CPME using 0.1 M aqueous thiourea solution. As the solubility of water into CPME is much smaller than that into alcohols such as 1-hexanol, CPME is more favorable as an extractant for Au(III) in hydrochloric acid media.