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Experimental and theoretical studieson thermodynamic propertiesof three ionic liquids based on dicyanamide anion (namely, 1-butyl-3-methylimidazoliumdicyanamide, 1-butyl-1-methylpyrrolidinium dicyanamide, and 1-butyl-1-methylpiperidiniumdicyanamide) and their binary mixtures with sugar alcohols (d-sorbitol and xylitol) were conducted in order to assess the applicabilityof the salts ionic liquids for dissolution of those biomass-relatedmaterials. Density and dynamic viscosity (at ambient pressure) ofpure ionic liquids are reported in the temperature range from T= 293.15 to 363.15 K. Solid–liquid equilibriumphase diagrams in binary systems {sugar alcohol + ionic liquid} weremeasured with dynamic method up to the fusion temperature of sugaralcohol. The impact of the chemical structure of both the ionic liquidand sugar alcohol were established and discussed. For the very firsttime, the experimental solubility data were reproduced and analyzedin terms of equation of state rooted in statistical mechanics. Forthis purpose, perturbed-chain statistical associating fluid theory(PC-SAFT) was employed. In particular, new molecular schemes for theionic liquids, d-sorbitol, and xylitol were proposed, andthen the pure chemicals were parametrized by using available densityand vapor pressure data. The model allowed accurate correlation ofpure fluid properties for both ionic liquids and sugar alcohols, whenthe association term is taken into account. The results of solid–liquidequilibria modeling were also satisfactory. However, one or two adjustablebinary corrections to the adopted combining rules were required tobe adjusted in order to accurately capture the phase behavior. Itwas shown that a consistent thermodynamic description of extremelycomplex systems can be achieved by using relatively simple (but physicallygrounded) theoretical tools and molecular schemes. [ABSTRACT FROM AUTHOR]