3. Hexane is used as a solvent to remove dirt and grease. At the end of a cleaning process, it is desirable to filter and recover a portion of the used hexane to reduce the environmental impact. The...

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Extracted text: 3. Hexane is used as a solvent to remove dirt and grease. At the end of a cleaning process, it is desirable to filter and recover a portion of the used hexane to reduce the environmental impact. The process can be represented by the following schematic: Clean hexane Dirty solvent Waste slurry Waste Filtered hexane The input to a steady-state hexane recovery process is the dirty solvent, which is fed at 200 g/hr and contains 85 wt% n-hexane (H), 5 wt% liquid contaminants (C), and the remainder solids (S). In the first unit, filtration produces two streams: a thick waste slurry that contains 72 wt% solids (all the solids that entered) and filtered hexane that still contains some residual liquid contaminants. The waste slurry then enters a second unit to evaporate and recover all the remaining hexane as a pure stream. A separate waste stream also exits. The ratio of hexane to liquid contaminants in the dirty solvent and filtered hexane are the same. а) Draw a complete flowchart for the process and clearly state any assumptions. b) complete a DOF analysis for the overall process. Clearly indicate the boundaries for the overall process with a dashed line, then c) How much clean hexane is recovered in g/hr? ] In a separate process, the evaporated hexane is isobarically cooled and condensed to a liquid. If the hexane has a vapor pressure of 0.78 atm, at what temperature will the first drop of liquid form? d)