The vapor pressure (VP) of 87 grade gasoline was
measured using an enhanced VP acquisition system over a temperature range of
approximately 19.0℃ (292.2 K) and 69.0℃ (342.2 K). The empirical data were used to predict the
thermodynamic entities the enthalpy of vaporization (ΔHvap) and the entropy of vaporization (ΔSvap) of gasoline. The
results of this investigation yielded a ΔHvap value of 35.1 kJ/mol and ΔSvap of 102.5 J/mol·K. The value of ΔHvap was in excellent agreement with the findings of a prior study (Balabin et al., 2007), which produced a ΔHvap values of 37.3 kJ/mol and 35.4 kJ/mol. The enthalpy and entropy of vaporization
of n-heptane (37.2 kJ/mol and 100.1 J/mol·K) and n-octane (39.1 kJ/mol and 98.3
J/mol·K) were also determined after acquiring VP data for the two VOCs. The
empirical results for n-heptane and n-octane were also in excellent agreement
with the literature. These favorable comparisons strengthen the capacity of our
system for acquiring the VP data for pure and volatile multi-component
mixtures.
Cite this paper
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