Thermodynamic assessment of the Bi–K binary system

Comment on “Thermodynamic assessment of the Bi–K binary system” by C. Niu, C. Li, Z. Du, C. Guo, M. Liu [Thermochimica Acta 528 (2012) 9–14]

“…In their paper, Niu et al [1] proposed thermodynamic assessment of the binary Bi-K system based on the available thermodynamic and phase equilibrium data. All the experimental information was analyzed and discussed in the commented paper [1].…”

“…All the experimental information was analyzed and discussed in the commented paper [1]. The liquid phase was described by an associate liquid solution model [2], which was developed by Sommer [2][3][4].…”

“…Let's try to use a more reasonable model, where the liquid phase contains Bi, K and BiK 3 . Furthermore, let's use Gibbs energies of all IMCs proposed by Niu et al [1]. It is not a surprise, that after using a simpler description of liquid, the result of assessment is very good.…”

“…4. A simpler model, which is based on more than one premises, gives very good reproduction of experimental data even without changing Gibbs energies of IMCs proposed by Niu et al [1].…”

“…All the reasons pointed above suggest that the associate BiK proposed by Niu et al [1] does not have purpose, makes description of the Bi-K system more complicated and troublesome in case of extending description to higher-ordered systems. Fig.…”