Analytical Methods for Determining the Concentration Ratio in Mixtures of Trioctylphosphine Oxide and Di(2-Ethylhexyl)Phosphoric Acid

Publisher Website
Google Scholar
Abstract
Analytical methods are described for determining the concentration ratio of trioctylphosphine oxide (TOPO) and di(2-ethylhexyl)phosphoric acid (D2 EHPA) in hydrocarbon solvents or in mixtures where the D2 EHPA is the solvent. The Electron Spectroscopy for Chemical Analysis (ESCA) method was used to analyze the mixtures for the relative amounts of phosphine oxide-phosphorus to phosphoric acid-phosphorus as well as the variance with the mixture composition of the Ols/P2p signal intensity. The nmr signal strength of the protons of the oxymethylene group of the D2 EHPA and the signal strength of the other protons of D2 EHPA and TOPO were measured in solutions of varying concentrations of D2 EHPA and TOPO. Mass spectral comparisons of the molecular ion strengths of TOPO and D2 EHPA were also correlated with mixture composition.