The Measurement and Calculation of Heat of Mixing for Aqueous Alkanolamine Solutions

The heat of mixing H
^E
for N,N-Diethylethanolamine(DEEA), 1-(2-hydroxyethyl) piperazine(HEPZ) in water were measured with C-80 calorimeter at two different T=(303.15, 323.15)K and over the entire range of mole fractions. The experimentally measured H
^E
values are correlated as a function of mole fractions using the Redlich-Kister (RK) equation. And the nonrandom two-liquid (NRTL) parameters were simultaneously fitted using VLE and H
^E
data with good agreement with experimental data.