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Experimental Methods, Results and Discussion
Table II.12: Solubility of Oxygen in n-Heptane. Comparison Between Data Measured in This
Work and Literature Data.
L2,1(T,p) (%)
T ( K) This work
Hesse et al.
(1996)
Makranczy et al.
(1976)
Gjaldbaek et al.
(1963)
298.15 0.335 ± 1 0.338 ± 0.5 0.322 ± 3 0.330 ± 1
Figures II.11 and II.12 intend to emphasize the temperature dependence of the
different systems studied. The influence of the chain length and structure of the molecule,
as shape and partial substitution of fluorine atoms, was studied .
The solute mole fraction is usually presented at a solute’s partial pressure equal to
1 atm. From solute’s mole fraction data reported in Table II.13, it is simple to calculate the
corrected solute mole fraction since the Henry’s law is applicable at the working
conditions. In order to check the validity of the Henry’s law for the systems under study,
the solubility of oxygen in perfluoro-n-nonane was measured at several pressures different
from atmospheric and at a fixed temperature of 298 K. Solubility data measured is given in
Figure II.13. The linear relation obtained confirms the validity of the Henry’s law for these
systems.
The temperature dependence of the experimental values of the solubilities
expressed in mole fraction x2 (T, P), where P is equal to 1 atm was correlated using the
following equation suggested by Benson and Krause (1976)
1
−i
ln x2
= ∑ AiT
(II.18)
i=
0
The values obtained for the coefficients Ai for the different systems are given in
Table II.14, together with the AAD of the experimental results defined as
AAD = N
N
−1
∑
i=
1
δ (II.19)
i
where N is the number of data points, whose individual percentage deviations are
calculated as:
[ x ( exp)
x ( calc)
] / x ( calc)
δ = 100 −
(II.20)
i 2
2
2
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