Popis: |
A comprehensive study of thermodynamic properties of trans-2-cyclohexylcyclohexanol (t-2CCOL) was carried out in this work. The subject compound is a by-product from the synthesis of 2-phenylphenol. The standard molar enthalpy of combustion of t-2CCOL, found by the bomb calorimetry method, Δ c H ° m (cr, 298.15 K)=−(7388.05±1.37) kJ · mol −1 , and the standard molar enthalpy of formation Δ f H ° m (cr, 298.5 K)=−(478.25±2.13) kJ · mol −1 . The molar sublimation and vaporization enthalpies of t-2CCOL were measured with a heat-conduction differential microcalorimeter Δ cr g H ° m (319.5 K)=(98.56±0.52) kJ · mol −1 ; Δ f g H ° m (345.8 K)=(80.31±0.34) kJ · mol −1 . Vapour pressure of t-2CCOL was measured by the integral effusion Knudsen method in the temperature range 293 K to 325 K for crystal: ln( p /Pa)=(37.30±0.22)−(11616±69) · T −1 , and in the temperature range 328 K to 364 K for liquid: ln( p /Pa)=(34.41±0.44)−(10013±150) · T −1 . The heat capacity of t-2CCOL was measured by the vacuum adiabatic calorimetry ( T =5 K to T =338 K). The fusion temperature of t-2CCOL is 325.8 K, and the molar enthalpy of fusion is Δ fus H ° m =(14.515±0.029) kJ · mol −1 . Standard molar thermodynamic functions of t-2CCOL in the crystalline state at T =298.15 K were obtained on the basis of these measurements: C p ,m =(248.68±0.99); Δ 0 T S ° m =(263.85±1.18); Δ 0 T H ° m / T =(130.52±0.51); Φ° m =(133.33±1.29) kJ · mol −1 . |