di2ethylhexylphosphoric

Bis(2-ethylhexyl) phosphoric acid, often abbreviated as DEHPA or D2EHPA, is an organophosphorus compound. It is a colorless to pale yellow viscous liquid. DEHPA is a diester of phosphoric acid with two 2-ethylhexyl alcohol molecules. Its chemical formula is C16H35O4P.

DEHPA is primarily known for its utility as a solvent extractant in hydrometallurgy. It is widely used for the separation and purification of various metal ions, particularly rare earth elements, uranium, cobalt, and nickel. The efficacy of DEHPA as an extractant stems from its ability to selectively complex with metal cations in aqueous solutions, transferring them into an organic phase. This process is crucial in the production of high-purity metals for various industrial applications, including electronics, magnets, and nuclear technology.

The extraction mechanism typically involves ion exchange, where the metal cation from the aqueous phase replaces the acidic proton of DEHPA in the organic phase. The solubility of DEHPA in common organic diluents like kerosene or sulfonated kerosene is a key factor in its widespread industrial application. Environmental considerations and handling procedures are important due to its chemical nature.