Using Fig. 15.5, without performing additional calculations, sketch the P-x-y diagram at 400 K showing the two-phase region. Make the sketch semi-quantitative to show the values where the phase envelope touches the axes of your diagram. Label the bubble and dew lines. Also indicate the approximate value of the maximum pressure.

Transcribed Image Text:

90 80 70 60 50 P (bar) 8 30 20 10 200 250 300 350 400 450 500 550 T(K) Figure 15.5 High pressure phase envelopes for the ethane + heptane system comparing the effects of composition according to the Peng-Robinson equation. The theory is entirely predictive because the Peng-Robinson equation has been applied with k = 0. X's mark the mixture critical points and the dashed line indicates the critical locus. The first and last curves represent the vapor pressures for the pure components.