Phase equilibria in the system CaO-Al2O3-B2O3-H2O at 23±1°C

Phase equilibria in the four-component system CaO-Al2O3-B2O3-H2O at 23 +/- 1 degrees C have been investigated Data obtained experimentally were used to construct a phase diagram showing the stability regions of the solid phases Ca(OH)(2), AI(OH)(3), the ternary hydrate 3CaO . Al2O3. 6H(2)O, and the two quaternary hydrates, 6CaO . Al2O3. 2B(2)O(3). 39H(2)O and 4CaO . Al2O3. 1/2B(2)O(3). 12H(2)O . Theoretical calculations were also performed using the speciation program PhreeqC, which gave results that were in close agreement with those obtained experimentally From this study, the solubility products (pK(sp)) for 6CaO . Al2O3. 2B(2)O(3). 39H(2)O and 4CaO . Al2O3. 1/2B(2)O(3). 12H(2)O were determined to be 44.23 and 28.51, respectively.