The ranking of all amines in terms of the values of the three
pKa s is presented in Table 4. It clearly shows
that all the studied amines have a higher pKathan MEA. 2-MPMDA, with two primary amino groups, has the highest
pKa1 and the second
pKa 2. It should be an amine of
great interest in carbon capture operations. DAOMDPA, with two primary
and a tertiary amino group, also has a high pKavalue. The coefficient of determination (R2) of the
linear regression for the Figure 1, 2, and 3 are presented in Table S5.
Table 4 pKa ranking at 298 K for all
amines