Deriving Equations for Complex Series Reaction.

[JPE1997]

Hi Guys,
I have the following 3 reactions:
1) C2H6 <-> C2H4 +H2 Ea = 65210kcal/kmol A = 4.65*10^13
2) 2C2H6 -> C3H8 + CH4 Ea = 65250kcal/kmol A = 3.85*10^11
3) C2H4 + C2H6 -> C3H6 + CH4 Ea = 60430kcal/kmol A= 7.08*10^13
I calculated K at 900K using the Arrhenius equation and found the selectivity of 1 to 2 to be 120, and 1 to 3 to be 0.6. So because 2 has little effect on the overall reaction I might neglect it. Is this a reasonable assumption? How can I derive equations to plot the concentration of each component over time? I was going to set it up as a series reaction but because the ethene formed in reaction 1 then reacts with the initial ethane concentration to give reaction 3. How would I set up the equations. I have only derived simple rate equations where A->B->C, but in this case it seems A <-> B + + A -> C + E, where is the inert hydrogen formed.

Thanks in advance.

 

[Latexman]

Homework?

We don’t do your homework.

Good Luck,
Latexman

 

[JPE1997]

It's for a design project. I dont want a final answer, just some advice on how to start. Im not sure how to account for the fact the ethene produced can react with the ethane produced.

 

[Latexman]

A design project for post graduate degree? MS or PhD?

TBH, it’s been decades since I’ve done this. Maybe someone will come along that can help.

Good Luck,
Latexman

 

[JPE1997]

It's for a final year undergraduate project.

 

[georgeverghese]

Presume A is the Arrhenius constant. Keep working at it, you'll get there. Chemical engineers with these skills are much sought after by operating companies with research labs.