Reuse of solvents is essential to making indirect carbonation technology economical and environmentally friendly. Despite its importance, however, no studies have been conducted to confirm the feasibility of reuse of solvents and to determine the conditions for the reuse. This study investigated the optimal conditions for critical factors affecting the reuse of solvents in indirect carbonation and the causes that make it difficult to reuse solvents. For the study, three chelating agents (citrate, malonate, and adipate) and cement kiln dust (CKD) were adopted as solvents and raw material. The end-of-carbonation pH of 10.5 and the concentration of 0.1 M were found to be the optimal conditions necessary for the reuse of chelating agents. Under the optimal conditions, the repeated use of chelating agents as solvents could not only result in high CO₂ storage and high yield and purity of CaCO₃, but also maintain them the same. Under non-optimal conditions, however, the concentration of bicarbonate ions in the remaining solution after carbonation increased significantly, causing the reuse of solvents to become very difficult. We provided strong evidence to support the reuse mechanism of the chelating agent through FT-IR analysis. We believe that our research on the reuse of solvents will contribute much to the commercialization of indirect carbonation technology.

溶剂的重复使用对于使间接碳酸化技术经济且对环境友好至关重要。尽管有其重要性，但尚未进行任何研究来确认溶剂再利用的可行性和确定再利用的条件。这项研究调查了影响间接碳酸化中溶剂再利用的关键因素的最佳条件，以及导致溶剂难以再利用的原因。为了进行研究，采用了三种螯合剂（柠檬酸盐，丙二酸盐和己二酸盐）和水泥窑粉尘（CKD）作为溶剂和原料。发现碳酸化结束的pH为10.5和浓度为0.1M是再利用螯合剂所必需的最佳条件。在最佳条件下，重复使用螯合剂作为溶剂不仅会导致高CO₂贮藏CaCO _3的产率和纯度高，但也保持它们不变。然而，在非最佳条件下，碳酸化后剩余溶液中碳酸氢根离子的浓度显着增加，导致溶剂的重复利用变得非常困难。我们通过FT-IR分析提供了有力的证据来支持螯合剂的重用机制。我们相信，我们对溶剂再利用的研究将对间接碳酸化技术的商业化做出巨大贡献。