Spectrophotometric determination of di(2-ethylhexyl), di(4-octylphenyl) and mono(4-octylphenyl)phosphoric acids with rhodamine-b

Abstract

A spectrophotometric method for the determination of di(2-ethylhexyl). di(4-octylphenyl) and mono(4-octylphenyl) phosphoric acids is described. The method was applied for their determination in aqueous raffinates from uranium extraction processes where they are employed as extractants. The reagent was a dichloroethane extract of rhodamine-B prepared from an aqueous phosphate buffer of pH 10. The organophosphoric acids were separated from the aqueous solution by extraction with dichloroethane and this organic extract was mixed with rhodamine-B reagent. The intense colour produced had maximal absorbance at sol560 565 nm. The molar absorptivity was about 10 5 in all cases.