A mixture of three hydrocarbons is at equilibrium at 100°C and 15 atmospheres. The can be assumed to form an ideal mixture in both the liquid and vapor phases. The composition of the mixture and the constants for the vapor pressure functions for each component are given below. The vapor pressure functions are of the form
ln P = A ? D/T
where P is in atmospheres and T is in Kelvins.
Component z A D
C3 0.25 9.816 2260
C4 0.40 9.922 2696
C5 0.35 10.173 3141
a) Determine whether the mixture is a subcooled liquid, a mixture of vapor and liquid, or a superheated vapor.
b) It is desired to bring the mixture to its bubble point (saturated liquid). If temperature is maintained at 100°C, to what total pressure must the mixture be subjected to reach the bubble point?
c) If pressure is maintained at 15 atmospheres, to what temperature must the mixture be adjusted to reach the bubble point? An answer within a few degrees centigrade is acceptable.
