(3) A 55 mol% feed of benzene in styrene is to be enriched in a batch...

 

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(3) A 55 mol% feed of benzene in styrene is to be enriched in a batch differential-distillation operation. The initial amount in the still is 150 moles, and the still operates at 101.3 kPa. The vapour pressure relationships for benzene and styrene can be determined from Antoine's equation: log (Psat) A- B T+C where psat is the saturated vapour pressure in kPa and 7 is temperature in °C. Benzene Styrene A₁ 6.0191 6.0490 B₁ 1204.6 1420 Ci 220.10 206 (a) For the system pressure of 101.3 kPa, plot: i. T-x-y diagram ii. x-y equilibrium diagram (7 marks) (3 marks) (b) Solve Rayleigh's relationship graphically to determine the amount that needs to be distilled to obtain a still residue composition of 10 mol%. What is the average distillate composition? (10 marks) (c) Given that the mean relative volatility is 6.582, repeat part (b) using the analytical solution of Rayleigh's relationship. Compare your solutions with those obtained in part (b). (5 marks) Note: The use of Excel is allowed, but do not submit spreadsheets; instead copy your solutions into a Word document and then submit. Label your graphs. To receive full marks, you must show all working. (3) A 55 mol% feed of benzene in styrene is to be enriched in a batch differential-distillation operation. The initial amount in the still is 150 moles, and the still operates at 101.3 kPa. The vapour pressure relationships for benzene and styrene can be determined from Antoine's equation: log (Psat) A- B T+C where psat is the saturated vapour pressure in kPa and 7 is temperature in °C. Benzene Styrene A₁ 6.0191 6.0490 B₁ 1204.6 1420 Ci 220.10 206 (a) For the system pressure of 101.3 kPa, plot: i. T-x-y diagram ii. x-y equilibrium diagram (7 marks) (3 marks) (b) Solve Rayleigh's relationship graphically to determine the amount that needs to be distilled to obtain a still residue composition of 10 mol%. What is the average distillate composition? (10 marks) (c) Given that the mean relative volatility is 6.582, repeat part (b) using the analytical solution of Rayleigh's relationship. Compare your solutions with those obtained in part (b). (5 marks) Note: The use of Excel is allowed, but do not submit spreadsheets; instead copy your solutions into a Word document and then submit. Label your graphs. To receive full marks, you must show all working.

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Mol of benzene in feed x1 30 Benzene composition in product x2 45 Rel... View the full answer