Ionic liquids (ILs) are known for their high ability to capture CO₂. However, the mechanism of CO₂ solubility into ILs during their initial interaction remains controversial. In this study, we analyzed the initial dissolution of CO₂ into an IL 1-butyl-3-methylimidazolium bis-(trifluoromethylsulfonyl)imide ([C₄min] [NTf₂]) by measuring its solubility using a combination of a molecular beam and a flowing liquid jet sheet beam (FJSB) and the King and Wells method (KW method). The temperature dependence of the initial dissolution probability indicates that the solubility of CO₂ in the IL [C₄min] [NTf₂] increases with increasing temperature. This result is not consistent with what has been reported in an equilibrium state. The initial dissolution probability was well-fitted by the Vogel–Fulcher–Tammann (VFT) equation, which describes the dynamical cage structure in IL systems. We also find that the initial dissolution probability was correlated to the cage lifetime and correlation length. The simple model of CO₂ dissolution into an IL with the cage model was implemented to explain the experimental results in this study. Our results indicate that the initial dissolution of CO₂ into the IL corresponds to a direct solution and not an uptake process.

中文翻译：

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在最初相互作用期间，CO2直接溶解在离子液体中的证据[C4min] [NTf2]。

离子液体（ILs）以其高捕获CO _2的能力而闻名。然而，CO ₂溶解于IL的初始相互作用过程中的机制仍存在争议。在这项研究中，我们通过结合分子束测量其溶解度，分析了CO ₂在IL 1-丁基-3-甲基咪唑鎓双-（三氟甲基磺酰基）酰亚胺中的初始溶解（[C ₄ min] [NTf ₂ ]）流动的液体射流薄板梁（FJSB）和King and Wells法（KW法）。初始溶解概率的温度依赖性表明，CO ₂在IL中的溶解度[C ₄ min] [NTf ₂随温度升高而增加。该结果与平衡状态下的报道不一致。Vogel-Fulcher-Tammann（VFT）方程很好地拟合了初始溶解可能性，该方程描述了IL系统中的动态笼结构。我们还发现，初始溶出概率与笼寿命和相关长度有关。采用笼模型，将CO ₂溶解到IL中的简单模型用于解释本研究的实验结果。我们的结果表明，CO ₂到IL中的初始溶解对应于直接溶液，而不是吸收过程。