Prior to this study no data for the solubility product of BiPO4(cr) or the complexation constants of Bi with phosphate were available. The solubility of BiPO4(cr) was studied at 23 ± 2 °C from both the over- and under-saturation directions as functions of a wide range in time (6–309 days), pH values (0–15), and phosphate concentrations (reaching as high as 1.0 mol·kg-1). HCl or NaOH were used to obtain a range in pH values. Steady state concentrations and equilibrium were reached in 9.0, Bi(OH)3(am) is the solubility controlling phase. Reliable values for the Bi(OH)3(am) solubility reactions involving Bi(OH)3(aq) and Bi(OH) - 4 and the formation constants of these aqueous species are also reported.
Revised: October 22, 2010 |
Published: July 1, 2010
Citation
Rai D., M. Yui, H.T. Schaef, and A. Kitamura. 2010.Thermodynamic Model for BiPO4(cr) and Bi(OH)3(am) Solubility in the Aqueous Na+–H+–H2PO- 4 –HPO2- 4 –PO3- 4 –OH-–Cl-–H2O System.Journal of Solution Chemistry 39, no. 7:999-1019.PNNL-SA-75194.doi:10.1007/s10953-010-9561-6