Highly selective extraction of Pd(II) with 5-octyloxymethyl-7-bromo-8-quinolinol from acidic solution

A novel extractant, 5-octyloxymethyl-7-bromo-8-quinolinol (HBrO 8 Q), was employed to extract Pd(II) from low-acidity aqueous solution. The extraction behaviors indicated that HBrO 8 Q had high extraction efficiency and selectivity for Pd(II) under the experimental conditions, and the stoichiometry of Pd(II) with HBrO 8 Q was found to be 1:1 by means of mole ratio method and Job’s method. The thermodynamic study indicated that the extraction process was endothermic and spontaneous. Additionally, complete back extraction of palladium could be achieved by using acidic thiourea solution.