This study presents experimental data on water content in CO, methane, and their mixtures. A new saturation process was developed using a PVT cell connected to a variable-volume cylinder filled with deionized water. Dry gas with a known composition was injected into the cylinder, and the temperature and pressure conditions were adjusted accordingly. The water content of the saturated gas was then analyzed using a quartz-crystal microbalance (QCM). Various mixtures with different CO and methane mole ratios were investigated at different pressures for a given temperature. The PC-SAFT and CPA equations of state were applied to correlate the moisture data. The association scheme employed included 2B, 3B, and 4C types, considering the cross-association between water and CO. The results for pure methane showed that the water content increased as the pressure decreased across all pressure ranges. However, for pure CO above 70 bar, the water content increased due to the condensation behavior of CO. The same trend was observed for mixtures, where the water content increased with increasing pressure for CO mole fractions above 0.74. For all the systems studied, the PC-SAFT and CPA equations of state successfully correlated the water content data using a single constant binary interaction parameter and considering the cross-association between water and CO.

中文翻译：

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CO2–CH4 混合物中的水含量：使用石英晶体微量天平的新饱和度设置和测量。

这项研究提供了二氧化碳、甲烷及其混合物中水含量的实验数据。使用连接到充满去离子水的可变容量钢瓶的 PVT 电池开发了一种新的饱和工艺。将已知成分的干燥气体注入气缸内，并相应调整温度和压力条件。然后使用石英晶体微天平（QCM）分析饱和气体的水含量。在给定温度、不同压力下研究了具有不同 CO 和甲烷摩尔比的各种混合物。应用 PC-SAFT 和 CPA 状态方程来关联水分数据。考虑到水和 CO 之间的交叉关联，所采用的关联方案包括 2B、3B 和 4C 类型。纯甲烷的结果表明，在所有压力范围内，水含量随着压力降低而增加。然而，对于高于 70 bar 的纯 CO，由于 CO 的冷凝行为，水含量增加。对于混合物，观察到相同的趋势，其中当 CO 摩尔分数高于 0.74 时，水含量随着压力的增加而增加。对于所有研究的系统，PC-SAFT 和 CPA 状态方程使用单个常数二元相互作用参数并考虑水和 CO 之间的交叉关联，成功地将含水量数据关联起来。