Solvent extraction of copper(II) from chloride media using N-(thiocarbamoyl)benzamidine and N-benzoylthiourea derivatives Original Research Article

The distribution of copper(II) between aqueous solutions and cumene solutions of N-(thiocarbamoyl)benzamidine, 2a–2c, and N-benzoylthiourea derivatives, 3a–3f, from chloride media (1 mol/l NaCl) has been studied in detail. The metal extraction was greatly influenced by extractant structure of thiourea derivatives. The extractability of Cu(II) with extractants 2a–2c and 3a–3f followed the order as: 3e>3d∼3c∼3f>3b≫3a∼2a∼2b∼2c, respectively. The N-thiocarbamoylbenzamide derivatives (2a–2c) are comparatively poor extractants than N-benzoylthiourea derivatives (3a–3f). The organic reagents 3a–3e were selected for detailed further studies owing to their better extraction behavior with copper(II). The extraction equilibria was studied as a function of total copper concentration, pH of the aqueous phase and total extractant concentration. It was shown by use of equilibrium modeling computer program LETAGROP-DISTR that the extraction of Cu(II) could be explained assuming the extraction of the species CuL2, where L=3c. The equilibrium constants calculated by this program were also reported.