2.7. Measurement of heat regeneration
The heat of regeneration of spent AC-MEA and AC-DEA were measured by a differential scanning calorimeter (DSC) (PerkinElmer, DSC 7, USA). The DSC analyses were carried out under N2
atmosphere at a flow rate of 100 mL/min and with a heating rate of 5 C/min from an adsorption temperature of 70 C to a desorption temperature of 160 C (AC-MEA samples) or to 170 C (AC-DEA
samples). The heat release/uptake from the sample (J/g sample) was estimated by integrating the area under the peak emerging during the heating [33]. The amount of CO2 desorbed by a sample (mol CO2/g sample) was measured by a TGA (PerkinElmer, TGA 7, USA) under the same conditions as the DSC analysis. Heat values were then calculated in terms of heat per mole of adsorbed CO2 (Qregen., kJ/mol CO2).