Developing a Vial-Scale Methodology for the Measurement of Nucleation Kinetics Using Evaporative Crystallization: A Case Study with Sodium Chloride

Abstract

Understanding nucleation kinetics is vital for designing crystallization processes, yet traditional measurement methods based on cooling are unsuitable for compounds with temperature-independent solubility. This study introduces an experimental procedure to measure the nucleation kinetics based on evaporative crystallization and applies it to sodium chloride (NaCl) in water. By systematically varying the experimental conditions such as temperature and evaporation gas flow rate, we obtained a comprehensive data set for the nucleation of NaCl crystals that allowed estimating kinetic parameters using a rate expression derived from classical nucleation theory (CNT). This work demonstrates the robustness of evaporation as a method for measuring the nucleation kinetics that is applicable regardless of how the solubility of a compound depends on the temperature.

This study introduces a vial-scale evaporative crystallization method to measure nucleation kinetics applied to aqueous sodium chloride (NaCl). By integrating experimental data and classical nucleation theory, it highlights the influence of evaporation rates on supersaturation and metastable zone width. The method demonstrates reproducibility and scalability, offering a robust framework for crystallization studies.