Extraction of neodymium(III) from aqueous solutions by solvent extraction with Cyanex® 572

The present research aims at studying the extractability of Nd(III) by Cyanex® 572 as a new extractant form from nitrate solutions. The effects of contact time, the concentration of nitrate ion, hydrogen ion, and extractant, and type of diluent were discussed, suggesting that the extraction of neodymium with Cyanex 572 was found to be a cation-exchange mechanism releasing three $H^+$ ion during the extraction. Cation- exchange mechanism of Nd(III) with Cyanex 572 was studied using slope analysis. Hydrogen ion concentration strongly influences the extraction behavior of Nd(III) in the solvent extraction. Results showed that three moles of Cyanex 572 are incorporated in the extraction process of one-mole neodymium(III) from the aqueous solutions. The concentration of nitrate ion in the aqueous solution has positive effect on the extraction efficiency of neodymium due to the salting out effect. The type of diluent influences the extraction efficiency of Nd(III). Results indicated that non-polar diluents were suitable solvents for the extraction of neodymium(III).