Thermodynamic and acoustic properties of binary mixtures of 1-butanol with 1,2-butanediol. The comparison with the results for 1,3-, and 1,4-butanediol

• Excess molar volume is negative and absolute value decreases with temperature.
• Excess molar isobaric heat capacity is positive and decreases with temperature.
• Slight contraction and enhanced rigidity observed in mixtures.
• Increase of non-chemical attractive interactions in mixtures.
• Correlation between isobaric molar heat capacity excesses and molar isobaric heat capacities of the pure butanediols.

Densities and isobaric heat capacities have been measured for (1-butanol + 1,2-butanediol) over the temperature range from (293.15 to 308.15) K and (282.15 to 320.15) K, respectively. The speed of sound at the temperature 298.15 K has been measured as well. Using these results, the molar volumes, isentropic and isothermal compressibility coefficients, molar isentropic and isothermal compressibilities, molar isobaric and isochoric heat capacities as well as internal pressures were calculated. Also the corresponding excess and deviation values were calculated and expressed by Redlich–Kister polynomials. The results are discussed in terms of variations of the structure of the system caused by the participation of the two alcohols (with the same carbon chain but different hydroxyl groups) in the dynamic intermolecular association process through hydrogen bonding at various temperatures. Present findings are also compared with the previous results for 1,3-, and 1,4-butanediol.