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Design a distillation column to separate a mixture of ethanol and water. The feed stream contains 20 mol% ethanol and the desired distillate should contain at least 95 mol% ethanol. The reflux ratio should be 3:1 and the column should have 25 theoretical trays. Determine the composition of the distillate, bottoms, and the optimal feed tray location to achieve the desired separation. Use McCabe-Thiele method to deter

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To design a distillation column using the McCabe-Thiele method, we need to follow these steps:1. Obtain the vapor-liquid equilibrium  VLE  data for the ethanol-water system. For simplicity, we will assume that the system follows the ideal behavior  Raoult's Law . The VLE data can be found in literature or simulated using software like Aspen Plus or ChemCAD.2. Determine the operating conditions:    - Feed composition  xF : 20 mol% ethanol   - Desired distillate composition  xD : 95 mol% ethanol   - Reflux ratio  R : 3:13. Draw the McCabe-Thiele diagram:   - Plot the VLE curve on the x-y diagram  x: liquid phase composition, y: vapor phase composition    - Mark the feed and distillate compositions on the x-axis  xF = 0.20, xD = 0.95    - Draw the q-line from the feed point  q is the fraction of liquid in the feed, which depends on the feed temperature    - Draw the operating lines for the rectifying  top  and stripping  bottom  sections using the reflux ratio and q-line intersection   - Perform a stepwise construction between the operating lines and VLE curve to determine the number of theoretical trays required4. Analyze the McCabe-Thiele diagram:   - Count the number of steps  theoretical trays  required to achieve the desired separation   - Determine the optimal feed tray location by finding the tray where the q-line intersects the operating lines   - Estimate the composition of the bottoms  xB  by extrapolating the stripping section operating line to the x-axisBased on the given information  25 theoretical trays and 3:1 reflux ratio , we can perform the McCabe-Thiele analysis. However, without the actual VLE data, we cannot provide the exact values for the distillate, bottoms, and feed tray location. Once you have the VLE data and complete the McCabe-Thiele diagram, you can determine if the desired separation  95 mol% ethanol in the distillate  can be achieved with the given number of trays and reflux ratio. If not, you may need to adjust the column design  e.g., increase the number of trays or reflux ratio  to meet the desired product specifications.

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