Abstract Accurate fluid phase equilibria modeling of carbon dioxide-methanol binary system is essential for numerous industrial applications. Prior modeling studies were limited in scope in terms of temperature and pressure ranges. In this study, the phase equilibria behavior of the binary system is modeled with cubic equations-of-state (EoS) including Peng-Robinson (PR) and Soave-Redlich-Kwong with various mixing rules, Predictive Soave-Redlich-Kwong, Cubic Plus Association, and Perturbed-Chain Statistical Associating Fluid Theory. Among them, the classical PR EoS and its variants yield the overall best results in representing the phase behavior at temperature above 330 K. However, PR incorrectly predicts two liquid phases when the CO2 mole fraction exceeds ∼ 0.4 at temperature lower than 330 K. Raoult's law with the classical nonrandom two-liquid excess Gibbs energy model is recommended for the low temperature conditions.

中文翻译：

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模拟二氧化碳-甲醇二元体系的流体相平衡

摘要 二氧化碳-甲醇二元体系的准确流体相平衡建模对于众多工业应用至关重要。先前的建模研究在温度和压力范围方面受到限制。在这项研究中，二元系统的相平衡行为用三次状态方程 (EoS) 建模，包括 Peng-Robinson (PR) 和 Soave-Redlich-Kwong，具有各种混合规则，Predictive Soave-Redlich-Kwong，Cubic加上关联和扰动链统计关联流体理论。其中，经典的 PR EoS 及其变体在表示高于 330 K 的温度下的相行为方面产生了总体最佳结果。 然而，当 CO2 摩尔分数在低于 330 K 的温度下超过 0.4 时，PR 错误地预测了两个液相。 Raoult '