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An equimolar liquid mixture of benzene and toluene is separated into two product streams by distillation. A process flowchart and a somewhat oversimplified description of

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An equimolar liquid mixture of benzene and toluene is separated into two product streams by distillation. A process flowchart and a somewhat oversimplified description of what happens in the process follow: Inside the column a liquid stream flows downward and a vapor stream rises. At each point in the column some of the liquid vaporizes and some of the vapor condenses. The vapor leaving the top of the column, which contains 97.0 mole\% benzene, is completely condensed and split into two equal fractions: one is taken off as the overhead product stream, and the other (the reflux) is recycled to the top of the column. The overhead product stream contains 91.2% of the benzene fed to the column. The liquid leaving the bottom of the column is fed to a partial reboiler in which 40.0% of it is vaporized. The vapor generated in the reboiler (the boilup) is recycled to become the rising vapor stream in the column, and the residual reboiler liquid is taken off as the bottom product stream. The compositions of the streams leaving the reboiler are governed by the relation xB/(1xB)yB/(1yB)=2.25 where yB and xB are the mole fractions of benzene in the vapor and liquid streams, respectively. Degrees of Freedom Take a basis of 100 mol fed to the column. Draw and completely label a flowchart, and for each of six systems (overall process, column, condenser, reboiler, column and condenser, and column and reboiler), do the degree-of-freedom analysis, Identify which of the following systems have zero degrees of freedom and thus would be good starting points for analysis. Choose one. Overall System Reboiler Only Column and Reboiler Column Only Use the constraint on benzene recovery in the overhead to solve for the total overhed flow (n1(m0)). Attempts: 0 of 10 used Bottoms Rate and Composition Calculate the amount and composition of the bottoms product and the percent recovery of the toluene fed in the bottoms ( 100x moles of toluene in bottoms/moles toluene in feed). Amount of bottoms product: mol Mole fraction of benzene in the bottoms product: Percent recovery of the toluene fed in the bottoms product: Reboiler Feed and Boilup Calculate the amount and composition of the feed to the reboiler and the amount and composition of the boilup. Mole fraction of benzene in the boilup: Amount of boilup: mol Amount of feed to reboiler: Mole fraction of benzene in reboiler feed

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