Density and viscosity of deep eutectic solvents at different temperatures and compositions: Measurement and prediction model

Abstract Deep eutectic solvents (DESs) are becoming increasingly promising as environmentally friendly solvents, and accurate prediction of their density and viscosity is crucial for their successful industrial application. However, existing density and viscosity prediction models primarily rely on temperature variations and often overlook changes in the molar ratio of hydrogen bond acceptors (HBA) to hydrogen bond donors (HBD) in DESs, limiting their practicality. Therefore, in this study, several binary and ternary DESs were synthesized using choline chloride (ChCl) as the hydrogen bond donor. The densities and viscosities of these DESs were measured, and prediction models for the density and viscosity of DESs based on temperature and molar ratio were developed. These models were used to forecast the density and viscosity of DESs at different temperatures and molar ratios. The model parameters are calibrated using experimental data from this research. Finally, the model is utilized to predict the density and viscosity of DESs mentioned in this paper, as well as DESs with varying HBAs and HBDs. The results demonstrate that the discrepancy between the literature value, experimental value, and calculated value is less than 6%, confirming the universal applicability and reliability of the prediction model proposed in this study.