Dialkylphosphinic acid
Dialkylphosphinic acids are organophosphorus compounds with the formula R2PO2H, where R is any alkyl group. They are phosphorus(V) compounds with tetrahedral molecular geometry. Under the brand names Aerophine and Cyanex, they are used in extraction and separation, i.e., hydrometallurgy, of metal salts from ore extracts.[1] Characteristically the organic substituents are branched to confer solubility and preclude crystallization.[2][3]
The dithiodialkyphosphinic acids (R2PS2H) are related to the diorganodithiophosphates with the formula (RO)2PS2H, which are also used as complexing agents in the purification of metals. The phosphates are more prone to hydrolysis owing to the greater lability of the RO-P linkage vs the direct C-P bond.
References
- ^ J. Svara, N. Weferling, T. Hofmann "Phosphorus Compounds, Organic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2006. doi:10.1002/14356007.a19_545.pub2
- ^ Ayanda, Olushola S.; Adekola, Folahan A.; Baba, Alafara A.; Ximba, Bhekumusa J.; Fatoki, Olalekan S. "Application of Cyanex extractant in Cobalt/Nickel separation process by solvent extraction" International Journal of Physical Sciences 2013, vol. 8, pp. 89-97. doi:10.5897/IJPS12.135
- ^ I.Yu. Fleitlikh, N.A. Grigorieva, , V.I. Kuz'min, G.L. Pashkov "Redox processes during cobalt extraction with bis(2,4,4-trimethylpentyl)dithiophosphinic acid" Hydrometallurgy 2012, volumes 129–130, pp. 43–49. doi:10.1016/j.hydromet.2012.08.009