Fabrication of boric acid and sodium sulfate from borax

Mergen A., Demirhan M., BİLEN M.

CFI-CERAMIC FORUM INTERNATIONAL, vol.81, no.3, 2004 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 81 Issue: 3
  • Publication Date: 2004
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: boric acid, borax, sodium sulfate, crystallization
  • Gazi University Affiliated: No


Boric acid production was made from borax solutions with concentrations of 183 and 245 g/l B2O3. Sodium sulfate was recovered as a by-product during boric acid fabrication. 183 g/l B2O3 was the optimum concentration for the boric acid production. Boric acid production yield and boric acid purity were around 91% and 96,7% respectively for the concentration value of 183 g/l B2O3. Boric acid fabrication can be carefully controlled by measuring the pH of the borax and boric acid solutions. Reaction times of between 5 and 90 min during boric acid production from borax solution of 183 g/l B2O3 did not have significant impact on the boric acid production yield and boric acid purity. Rafinated boric acid and sodium sulfate crystals had purities of over 99%. Rafinated boric acid and sodium sulfate crystals were characterised using X-ray diffraction (XRD), differential thermal and thermogravimetric analysis (DTA-TG) and scanning electron microscopy (SEM).