关键词: 1;2-cyclohexanediol;melting point;melting enthalpy;heat capacity;combustion enthalpy; formation enthalpy

Abstract: The thermodynamic properties of different geometric structures of 1,2-cyclohexanediol which
were rarely reported in literature, such as combustion enthalpy, formation enthalpy,
melting enthalpy and heat capacities, were determined by NETZSCH DSC 204 Scanning
Calorimeter. The relationship between the melting point and the composition for the mixture
system of cis-1,2-cyclohexanediol and trans-1,2-cyclohexanediol was investigated and
corresponding phase diagram was obtained. The melting enthMpies of both cis-1,2-
cyclohexanediol and trans-1,2-cyclohexanediol are 20.265 kJ·mol-1 and 16.368 kJ·mol-1
respectively. The standard combustion enthalpies of cis- and trans-1,2-cyclohexaneddiol
were determined by calorimeter. They are respectively -3507.043 kJ·mol-1 and -3497.8 k J·
mol-1 at 298.15 K.The standard formation enthalpies are respectively 568.997kJ·mol-1and
578.240kJ·mol-1 for cis- and trans-1,2-cyclohexaneddiol.

Key words: 1, 2-cyclohexanediol, melting point, melting enthalpy, heat capacity, combustion enthalpy