Relative Volatility in a Non-Ideal System

In summary, the speaker is asking if the relative volatility of a substance in a non-ideal multicomponent mixture will change when the temperature is increased or decreased by 30 C. They mention that they have calculated the activity coefficient using the UNIFAC method and are considering using computer calculations to get a better understanding of the situation.
  • #1
phantom19
3
0
May I Ask Another Ques?

Because I want to know the distribution of component of a non-ideal multicomponent mixture in a distillation column, I had calculated the activity coefficient for a particular multicomponent system at a temperature, let's say 60 C.
Thus I can obtain its relative volatility afterwards.

The question is would the relative volatility of this substance change or stays approximately the same when the T is being increased or decreased by let's say 30 C , considering that this system is a non ideal VLE system? I am doing this part because I wish to know its overhead temperature and distillate's temperature...

If the answer is "No"..I have to recalculate the activity coefficient but this is rather tedious as I am using UNIFAC method to calculate activity coefficient..so can I just assume that the changes in relative volatility is slight upon changes in temperature?
 
Engineering news on Phys.org
  • #2
The thing to do is to do some scouting calculations using UNIFAC for some estimated conditions to get an idea how it plays out. Of course, using computers to do the detailed calculations does not require one to assume constant relative volatility.
 

1. What is relative volatility?

Relative volatility refers to the ratio of vapor pressures of two components in a liquid mixture at a given temperature. It is a measure of the difference in ease of evaporation between the two components.

2. How is relative volatility calculated?

Relative volatility is calculated by dividing the vapor pressure of the more volatile component by the vapor pressure of the less volatile component. The values for vapor pressure can be obtained from experimental data or calculated using thermodynamic models.

3. What is a non-ideal system?

A non-ideal system is a mixture of two or more substances that does not follow the ideal gas law or ideal solution behavior. This means that the interactions between the molecules of the components are not negligible and can affect the properties of the system.

4. How does non-ideality affect relative volatility?

In a non-ideal system, the interactions between the components can cause deviations from ideal behavior, resulting in a non-constant relative volatility. This means that the relative volatility may vary with temperature, pressure, and composition of the mixture.

5. What factors can influence relative volatility in a non-ideal system?

Some factors that can influence relative volatility in a non-ideal system include temperature, pressure, composition of the mixture, and the nature of the interactions between the components. Additionally, the presence of impurities or azeotropes in the system can also affect relative volatility.

Similar threads

Volumetric flow rate ratio calculation
    • Materials and Chemical Engineering
Replies
1
Views
437
What determines the pressure inside this experimental setup?
    • Materials and Chemical Engineering
Replies
2
Views
279
Is my fictional Solar System stable and realistic?
    • Sci-Fi Writing and World Building
Replies
21
Views
1K
Calculate Mass of Non-Volatile Solute in Octane to Reduce V.P. 80%
    • Biology and Chemistry Homework Help
Replies
1
Views
1K
Standard Activity in Electrochemistry
    • Chemistry
Replies
2
Views
847
Calculating K Values (VLE Coefficients)
    • Materials and Chemical Engineering
Replies
2
Views
10K
Problems with Extractive Distillation of C4 to Get Butadiene
    • Materials and Chemical Engineering
Replies
1
Views
4K
A question about energy of condensation for an ideal multicomponent system
    • Materials and Chemical Engineering
Replies
1
Views
3K
Calculate ideal-gas temperature of a material
    • Introductory Physics Homework Help
Replies
2
Views
537
I Irreversible adiabatic processes & entropy change (clarification needed)
    • Thermodynamics
Replies
22
Views
2K

Hot Threads

Recent Insights

Back
Top