We have developed a general model to predict CO₂ equilibrium solubility in aqueous tertiary amine solutions by relating the equilibrium constant (K₁) to all relevant parameters in a logical function form. Testing our model, we measured CO₂ equilibrium solubility data for N-methylmorpholine (NMM) and N-ethylmorpholine (NEM) across various conditions. Comparison with six existing models reveals our general model's superior predictive performance not only for NMM and NEM but also for an additional 10 tertiary amine solutions from literature, indicating its universality. Comprehensively considering the CO₂ equilibrium solubility, amine dissociation constant (pKa) and the CO₂ absorption heat, it is found that NMM and NEM may be promising desorption promoters enabling to reduce the energy cost. In short, it is expected the general model can be applied to more other tertiary amine systems.

中文翻译：

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预测叔胺水溶液体系中 CO2 平衡溶解度的通用模型


我们开发了一个通用模型，通过将平衡常数 ( K ₁ ) 与逻辑函数形式的所有相关参数相关联来预测叔胺水溶液中的 CO ₂平衡溶解度。测试我们的模型时，我们测量了不同条件下 N-甲基吗啉 (NMM) 和 N-乙基吗啉 (NEM) 的 CO ₂平衡溶解度数据。与 6 个现有模型的比较表明，我们的通用模型不仅对 NMM 和 NEM 具有优异的预测性能，而且对文献中的另外 10 种叔胺溶液也具有优异的预测性能，表明其普适性。综合考虑CO ₂平衡溶解度、胺解离常数(pKa)和CO ₂吸收热，发现NMM和NEM可能是有前景的解吸促进剂，能够降低能源成本。总之，预计通用模型可以应用于更多其他叔胺体系。