Separation of Boron from Borated Paraffin Wax by Pyrohydrolysis and Alkali Extraction Methods and Its Determination Using Ion Chromatography

Abstract

A method based on the pyrohydrolysis extraction of boron and its quantification with ion chromatography was proposed for paraffin waxes borated with H₃BO₃ and B₄C. The optimum pyrohydrolysis conditions were identified. Wax samples were mixed with U₃O₈, which prevents the sample from flare up, and also accelerates the extraction of boron. Pyrohydrolysis was carried out with moist O₂ at 950°C for 60 and 90 min for wax with H₃BO₃ and wax with B₄C, respectively. Two simple methods of separation based on alkali extraction and melting wax in alkali were also developed exclusively for wax with H₃BO₃. 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).