Determination of kerosene, tributyl phosphate, dibutyl butylphosphonate, di-2-ethylhexylphosphoric acid and trioctylphosphine oxide in phosphoric acid

Kerosene, tributyl phosphate (TBP), dibutyl butylphosphonate, di-2-ethylhexylphosphoric acid and trioctylphosphine oxide in phosphoric acid were determined by gas chromatography. Toluene and TBP were chosen as internal standards. The organic contents in phosphoric acid were first extracted by carbon tetrachloride with an extraction efficiency of about 99%. The determination of low concentration organic constituents can be performed by an extraction - concentration method. The determination of three different peak patterns are discussed.