Metastable Phase Equilibrium of a Ternary System of K⁺,Mg²⁺/B₄O₇^2--—H₂O at 25°C

Abstract:

The isothermal solubility of the ternary system K+,Mg2+/B4O72-—H2O at 25°C has been studied and the phase diagram is determined. The results show that the system is of the simple eutonic type and can be in metastable equilibrium state within 8—16 hours. The phase diagram consists of two solubility branches corresponding to the crystallization areas of K2B4O7•4H2O and MgB4O7•9H2O. The composition of the eutonic point is MgB4O7,0.5279%(Wt%) and K2B4O7,13.9629%(Wt%) respectively. The replicate experiments proved that the phase transformation of hungtsaoite (MgB4O7•9H2O) occurs after a 20 hours epuilibrium.

• Periodical: Advanced Materials Research (Volume 662)
• Pages: 468-472
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.662.468
• Online since: February 2013
• Authors: Xiao Hua Ma, Sun Bai, Li Wu, Zhi Liang Jin
• Keywords: Borate Solubility, Metastable Phase Equilibrium, Ternary System

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