Question
Mass Transfer Question on Absorption
A gas stream containing 95 mol% CO₂ and 5 mol% ethanol is to be scrubbed with pure water in a counter-current, isothermal absorption column to remove ethanol. The desired composition of ethanol in the exit gas stream is 0.5 mol%. The equilibrium mole fraction of ethanol in the gas phase, y∗, is related to that in the liquid phase, x, as y∗=2x. Assume CO₂ is insoluble in water and neglect evaporation of water. If the water flow rate is twice the minimum, the mole fraction of ethanol in the spent water is:
A
0.0225
B
0.0126
C
0.0428
D
0.0316
Answer
0.0126
Explanation
Solution
The correct option is (B) :0.0126