Ultrasound/Complexing Agent-Assisted Solvent Extraction Behavior of Zn2+ with D2EHPA from Sulfuric Media Containing Transition and Rare-Earth (Fe, Ni, Cd, La, and Ce) Metal Ions

This research was conducted to specify the efficiency of an ultrasound/complexing agent-assisted solvent used to extract Zn2+ with di-(2-ethylhexyl) phosphoric acid (D2EHPA) from a sulfuric media containing Fe, Ni, Cd, La, and Ce metal impurities and compare it with a magnetic stirred system and in the absence of complexing agents. Two aqueous solutions were investigated, namely a solution containing (Zn, Fe, Ni, Cd) and a solution containing (Zn, Fe, Ni, Cd, Ce, La). The Zn extraction behavior in the presence of La and Ce rare earths was quite different than in their absence. The ultrasound power of 30 W created a good extraction and separation for Zn in the absence of the rare La and Ce metals, while in their presence, a power of 10 W was needed. Acetic acid (HAce), as a complexing agent, performed better than lactic acid (HLac) in Zn extraction and separation with an optimum concentration of 0.9 M and 0.6 M for the solution containing (Zn, Fe, Ni, Cd) and (Zn, Fe, Ni, Cd, Ce, La), respectively. The effect of masking Fe and Ni by both complexing agents reduced their extraction while increasing the extraction of Zn and Cd without altering the extraction of La and Ce. The synergic effect of the ultrasound produced different extraction and separation results in the presence of HAce and HLac. For both aqueous solutions, the best synergic effect for Zn occurred in 10 W and 30 W in the presence of HLac (0.3 M) and HAce (0.9 M), respectively.