a The transitional temperature (in K) of nitric acid condensation assisted with the amine by using default E-AIM input parameters.
b The limits of the Tc (in K) resulting from the uncertainties in vapor pressurep0 at 298 K of the amine (unless noted otherwise). The upper and lower limits of Tc were obtained by decreasing and increasing p0 at 298 K of the amine by a factor of 3.56, respectively.
c The relative difference in Tcbetween the UNIFAC and the Raoult’s law methods to determine activities of the amine in an aqueous solution.
d It is assumed that the uncertainty inTc was caused mainly by the uncertainties of thep0 (or KH when applicable) and activity estimations.
This uncertainty was within ± 0.05% when the Henry’s law constant KH of the amine was used. It was then conservatively estimated by using the extrapolated vapor pressure at 298 K based on the Antoine Equation of the amine.5 The enthalpy change at 298 K was extrapolated based on compiled data by Linstrom and Mallard.5 The heat capacity was assumed to be the same as that of TMA, −90 J•mol−1•K−1.
Both enthalpy change values of 70.0 kJ/mol and 77.9 kJ/mol5 produced similar results (<0.05% difference).
* The limits of the Tc (in K) resulting from the uncertainties in the Henry’s law constantKH at 298 K. The upper and lower limits ofTc were obtained by choosing the maximum and minimum KH values at 298 K from available literature values with stated method of determination in Sander.6 The temperature dependence of the Henry’s law constants was based on the values recommended by Linstrom and Mallard.5
** The relative uncertainties were estimated by comparing with the experimental observations (263 – 278 K) by Wang et al.2
# The relative uncertainties were less than 0.05%.
(a)