Laboratory of Thermodynamics, Department of Chemical and Biochemical Engineering, TU Dortmund University, Emil-Figge-Str. 70, D-44227 Dortmund, Germany.
Molecules. 2021 May 26;26(11):3176. doi: 10.3390/molecules26113176.
The presence of water in the form of relative humidity (RH) may lead to deliquescence of crystalline components above a certain RH, the deliquescence RH (DRH). Knowing the DRH values is essential, e.g., for the agrochemical industry, food industry, and pharmaceutical industry to identify stability windows for their crystalline products. This work applies the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) to purely predict the DRH of single components (organic acids, sugars, artificial sweeteners, and amides) and multicomponent crystal mixtures thereof only based on aqueous solubility data of the pure components. The predicted DRH values very well agree with the experimental ones. In addition, the temperature influence on the DRH value could be successfully predicted with PC-SAFT. The DRH prediction also differentiates between formation of hydrates and anhydrates. PC-SAFT-predicted phase diagrams of hydrate-forming components illustrate the influence of additional components on the hydrate formation as a function of RH. The DRH prediction via PC-SAFT allows for the determining of the stability of crystals and crystal mixtures without the need for time-consuming experiments.
水以相对湿度（RH）的形式存在可能导致某些 RH 以上的结晶成分发生潮解，即潮解相对湿度（DRH）。了解 DRH 值对于农化行业、食品行业和制药行业识别其结晶产品的稳定窗口至关重要。本工作应用受扰链统计关联流体理论（PC-SAFT）仅基于纯成分的水溶解度数据来纯预测单一成分（有机酸、糖、人工甜味剂和酰胺）及其多成分晶体混合物的 DRH。预测的 DRH 值与实验值非常吻合。此外，PC-SAFT 还可以成功预测温度对 DRH 值的影响。DRH 预测还可以区分水合物和无水物的形成。形成水合物的成分的 PC-SAFT 预测相图说明了其他成分对水合物形成的影响，这是一个 RH 函数。通过 PC-SAFT 进行的 DRH 预测允许在无需进行耗时的实验的情况下确定晶体和晶体混合物的稳定性。
