Steady State mass balance for separation of cyclopentadiene

[member 392791]

Hello,

Here is a homework problem that I have been working on. I am wondering if for the mass balance of substance A, do I include the terms in the reaction rate that involve species R and B? Also, wouldn't A and B start reacting in the pipe before they even go into the CSTR? (I guess put in 2 different pipes then!).

Also, I wasn't sure if my mass balance for the PFR is right, I'm pretty sure it isn't. The trouble is I don't know how to put it in terms of volumes when given moles for the PFR, so I just did a volume flow rate (or rather just a velocity I suppose, in terms of z, a length).

 

[KataKoniK]

Hello there,

Great job on working through this homework problem! You are correct in your thinking that the terms involving species R and B should be included in the mass balance for substance A. This is because substance A is being consumed in the reaction involving R and B, so it is important to account for those species in the mass balance.

In regards to your question about A and B reacting in the pipe before entering the CSTR, it is important to consider the residence time of the substances in the pipe. If the residence time is long enough, then yes, A and B may start reacting before entering the CSTR. In this case, it would be appropriate to include a separate pipe for the reaction to take place before entering the CSTR.

As for your mass balance for the PFR, it is important to consider the volume of the reactor when calculating the moles of substance A. If you are given moles, you can calculate the volume by using the ideal gas law. Alternatively, you can also calculate the volume flow rate using the given velocity and cross-sectional area of the reactor. Once you have the volume, you can then use it to calculate the moles of substance A and complete your mass balance.

I hope this helps and good luck with your homework! Let me know if you have any further questions. Keep up the good work!