Phase Envelope for Light Hydrocarbons

This page is designed to allow users to select a pure component or a mixture of components and determine either the vapor pressure curve for a pure component or the pressure-temperature phase envelope for a mixture. This page is currently using the Peng-Robinson equation of state to predict the properties of these mixtures. To try it out, create an input mixture using the form below and hit the submit button to start the calculations.

Initial Conditions

Do you wish to input a guess for a T,P point inside the phase boundary? This should only be necessary if the mole fraction-weighted critical point does not fall within the phase envelope or falls near a phase boundary and the algorithm used to generate points on the phase boundary fails.


Temperature: K

Pressure: kPaa


Select the components for your mixture from the lists below and enter the mole fraction of each component in the field to the right. If the mole fractions do not sum to one when you are done, they will be re-normalized for you.

Component 01:   Mole fraction:
Component 02:   Mole fraction:
Component 03:   Mole fraction:
Component 04:   Mole fraction:
Component 05:   Mole fraction:
Component 06:   Mole fraction:
Component 07:   Mole fraction:
Component 08:   Mole fraction:
Component 09:   Mole fraction:
Component 10:   Mole fraction: