Palladium extraction from chloride solutions with the disulfide of bis(2,4,4-trimethylpentyl)dithiophosphinic acid

ABSTRACT

Palladium extraction from chloride solutions with the disulfide of bis(2,4,4-trimethylpentyl)dithiophosphinic acid (L) is reported in this work. The rate of palladium extraction with the disulfide in toluene is slow but it increases in the presence of trioctylamine (TOA). Within 5 min, the degree of palladium recovery (ε) is 99.6%, whereas in the absence of TOA, it is only 19.0% in 10 min. The extraction systems based on the disulfide and TOA mixtures exhibit fast kinetics, high selectivity and can be used for the extraction of palladium from various industrial solutions.

KEYWORDS:

• Solvent extraction
• palladium chloride
• disulfide
• bis(2
• 4
• 4-trimethylpentyl)dithiophosphinic acid
• catalytic additives

Acknowledgements

The authors thank Dr. A.P. Zubareva from the Institute of Inorganic Chemistry, SB RAS, and Dr. D.S. Flett for their constructive remarks. Our special thanks go to CYTEC INDUSTRIES INC. Canada for free samples of the CYANEX extractants.