Phase behavior of carbon dioxide/water binary mixtures plays an important role in various CO₂-based industry processes. This work aims to screen a thermodynamic model out of a number of promising candidate models to capture the vapor–liquid equilibria, liquid–liquid equilibria, and phase densities of CO₂/H₂O mixtures. A comprehensive analysis reveals that Peng–Robinson equation of state (PR EOS) (Peng and Robinson 1976), Twu α function (Twu et al. 1991), Huron–Vidal mixing rule (Huron and Vidal 1979), and Abudour et al. (2013) volume translation model (Abudour et al. 2013) is the best model among the ones examined; it yields average absolute percentage errors of 5.49% and 2.90% in reproducing the experimental phase composition data and density data collected in the literature. After achieving the reliable modeling of phase compositions and densities, a new IFT correlation based on the aforementioned PR EOS model is proposed through a nonlinear regression of the measured IFT data collected from the literature over 278.15–477.59 K and 1.00–1200.96 bar. Although the newly proposed IFT correlation only slightly improves the prediction accuracy yielded by the refitted Chen and Yang (2019)’s correlation (Chen and Yang 2019), the proposed correlation avoids the inconsistent predictions present in Chen and Yang (2019)’s correlation and yields smooth IFT predictions.

二氧化碳/水二元混合物的相行为在各种基于CO ₂的工业过程中起重要作用。这项工作旨在从许多有前途的候选模型中筛选出一个热力学模型，以捕获CO ₂ / H ₂ O混合物的气液平衡，液液平衡和相密度。综合分析表明，国家的彭臣式（PR EOS）（彭和罗宾逊1976年），涂醒哲α功能（Twu等人，1991年），Huron-Vidal混合规则（Huron和Vidal，1979年）和Abudour等人。（2013）体积翻译模型（Abudour et al。2013）是所研究模型中最好的模型；在重现文献中收集的实验相组成数据和密度数据时，其平均绝对百分比误差为5.49％和2.90％。在实现了可靠的相组成和密度建模之后，通过对从文献中收集的278.15–477.59 K和1.00–1200.96 bar的IFT数据进行非线性回归，提出了一种基于上述PR EOS模型的新IFT相关性。尽管新提出的IFT相关性仅稍微改善了经过重新拟合的Chen和Yang（2019）的相关性（Chen and Yang 2019）的预测准确性，