To prove the feasibility of pyrometallurgical recovery of the rare earth elements, it is necessary to understand the thermodynamic properties of related rare earth oxides containing systems. Based on the experimental data as well as thermodynamic modelling of the silicate subsystems, a thermodynamic description of CaO-Gd₂O₃–SiO₂ ternary system is constructed. The Gibbs energy of the liquid phase is modeled by the Modified Quasichemical Model. The solid phases are modeled by the polynomial expansions of the excess Gibbs energy. The present modelling ternary phase equilibria are in good agreement with the experimental data in the literature.

中文翻译：

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CaO-Gd2O3-SiO2 系统的热力学评估

为了证明火法冶金回收稀土元素的可行性，有必要了解相关含稀土氧化物体系的热力学性质。基于硅酸盐子系统的实验数据和热力学模型，构建了CaO-Gd ₂ O ₃ -SiO ₂三元系统的热力学描述。液相的吉布斯能量由修正的准化学模型建模。固相通过多余吉布斯能量的多项式展开来建模。目前的建模三元相平衡与文献中的实验数据非常吻合。