A method based on the pyrohydrolysis extraction of boron and its quantification with ion chromatography was proposed for paraffin waxes borated with H
3BO
3 and B
4C. The optimum pyrohydrolysis conditions were identified. Wax samples were mixed with U
3O
8, which prevents the sample from flare up, and also accelerates the extraction of boron. Pyrohydrolysis was carried out with moist O
2 at 950°C for 60 and 90 min for wax with H
3BO
3 and wax with B
4C, respectively. Two simple methods of separation based on alkali extraction and melting wax in alkali were also developed exclusively for wax with H
3BO
3. In all the separations, the recovery of B was above 98%. During IC separation, B was separated as boron–mannitol anion complex. Linear calibration was obtained it between 0.1 and 50 ppm of B, and LOD was calculated as 5 ppb (
S/N = 3). The reproducibility was better than 5% (RSD).
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