Thermophysical characterization of deep eutectic solvents composed by D-sorbitol, xylitol or D(+)xylose as hydrogen bond donors

Deep eutectic solvents (DES), a class of green solvents of simple preparation, presents high biocompatibility being able to be applied by pharmaceutical and food industry. The aim of this work was to determine density, viscosity, and speed of sound of DES composed by sugar hydrogen bond donors (HBD) (D-sorbitol, xylitol and D(+)xylose) and cholinium chloride as hydrogen bond acceptor (HBA). In addition, the effect of HBA:HBD molar ratio and temperature on thermophysical properties was determined. Results implies that both HBA:HBD molar ratio and temperature influence the thermophysical characteristics of the DES. Higher temperatures decrease the DES density and viscosity and increase the speed of sound. The sorbitol displays the most compact structure presenting higher density, viscosity and speed of sound values when compared to xylitol and xylose-based DES. Results presented in this work may help in the application of sugar-based DES by food industry and in the understanding of these solvents behavior for future separation process studies.