Separation of Pd from Pt and Rh by solvent extraction method from waste solution.

Area of Science:

• Materials Science
• Chemical Engineering
• Hydrometallurgy

Background:

• Precious metal recovery from waste is crucial for sustainability.
• Efficient separation of palladium, platinum, and rhodium presents significant challenges.
• Ionic liquids offer promising alternatives for selective metal extraction.

Purpose of the Study:

• To investigate the extractive separation of palladium from platinum and rhodium using Cyphos IL 101.
• To evaluate the efficiency and selectivity of the proposed separation method.
• To explore the potential of using waste materials as a source for precious metal recovery.

Main Methods:

• Extractive separation using a 10% (v/v) solution of Cyphos IL 101 in toluene.
• Optimization of extraction parameters including pH, phase ratio (vorg:vaq), and contact time.
• Selective stripping of palladium using a 0.1 mol/dm3 thiourea solution.

Main Results:

• Achieved 99% extraction efficiency for both palladium (Pd) and platinum (Pt) under optimized conditions (pH 0.5, vorg:vaq 1:1, 15 min contact time).
• Demonstrated successful selective separation of palladium from platinum during the stripping stage.
• Confirmed high selectivity coefficients for the palladium-platinum separation.

Conclusions:

• Cyphos IL 101 is an effective ionic liquid for the co-extraction of palladium and platinum from dissolved waste materials.
• Selective palladium stripping using thiourea is a viable method for separating palladium from platinum.
• The developed process shows potential for the recovery and purification of precious metals from complex matrices.