Heat capacity of aqueous mixtures of monoethanolamine with 2-piperidineethanol

The binary system studied was monoethanolamine(MEA)+2-piperidineethanol (2-PE). Heat capacities of aqueous mixtures of MEA with 2-PE were measured from 30 to 80 °C with a differential scanning calorimeter (DSC). For mole fractions of water ranging from 0.2 to 0.8, 16 concentrations of the MEA+2-PE+water systems were studied. An excess molar heat capacity expression, using the Redlich–Kister equation for the composition dependence, is used to represent the measured Cp of alkanolamine aqueous solutions. The results of heat capacity calculation (overall average absolute percentage deviation) for a total of 176 data points for MEA+2-PE+water system are 0.2 and 7.4% for molar heat capacity and excess molar heat capacity, respectively. The heat capacity values of aqueous mixtures of MEA with 2-PE presented in this study are, in general, of sufficient accuracy for most engineering-design calculations when using MEA+2-PE+water as absorbent for acid gas removal process.