Solving Hexane Condensation Problem: Flow Rate & Recovery

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The discussion revolves around solving a hexane condensation problem involving a gas stream with 18.0 mole % hexane and nitrogen. Participants emphasize the importance of applying mass balance principles to determine the flow rate of the gas stream leaving the condenser and the percentage of hexane recovered as liquid. Initial confusion about how to start the calculations is noted, but guidance is provided on calculating the molar flow rate of the condensate. Ultimately, one participant reports successfully resolving the problem in class. The conversation highlights the relevance of understanding the flow rates and recovery percentages in chemical engineering processes.
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A gas stream contains 18.0 mole % hexane and the remainder nitrogen. The stream flows to a condenser, where its temperature is reduced and some of the hexane is liquefied. The hexane mole fraction in the gas stream leaving the condenser is .0500. Liquid hexane condensate is recovered at a rate of 1.50 L/min.

a) what is the flow rate of the gas stream leaving the condenser?
b) what percentage of the hexane entering the condenser is recovered as liquid?

yikes, no idea where to start. probably should calculate the molar flow rate of the condensate since the rates at which the hexane and nitrodgen enter the unit must equal the total rates at which they leave in the two exit streams - but how?
 
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jimithing said:
- but how?

One step at a time. The problem statement as posted is missing information. What's missing? Is the information available elsewhere in the text or course materials? You've already got the concept of mass balance --- "what goes in has to come out," or, "what comes out has to have gone in." And, you've picked an excellent place to take the first step in solving ---

jimithing said:
probably should calculate the molar flow rate of the condensate

--- now, does that help, lead to more specific questions, or is everything still clear as mud?
 
figured it out in class today, thanks
 
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