A counter-current packed tower will be used to remove H₂S vapor from a N₂-rich gas stream. In the present process, the inlet gas stream entering the bottom of the tower contains 5.0 mole% H₂S at a superficial molar flowrate of 10 kgmole/m²/h, and the processed gas stream exiting the top of the tower must contain no more than 1.0 mole% H₂S. Pure solvent containing no H₂S enters the top of the tower. The total molar concentration of the solvent (C_L) is 50 kgmole/m³.

The equilibrium distribution of H₂S between the gas and liquid at process temperature of 40 and 100 C, provided by Jones et al.*, is provided in the table. The total system pressure is 1.0 atm.
a. What is the superficial molar flowrate of the gas stream exiting the top of the tower?
b. What is the minimum solvent flowrate for the process? Compare results at 40 and 100 C and comment on the differences.

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PA (mm Hg) 0.00 0.96 3.00 9.10 43.10 59.70 106.00 40 C mol H₂S/ mol MEA 0.000 0.125 0.208 0.362 0.643 0.729 0.814 PA (mm Hg) 1.00 3.00 5.00 10.00 30.00 50.00 70.00 100.00 100 C mol H₂S/ mol MEA 0.029 0.050 0.065 0.091 0.160 0.203 0.238 0.279 *J. H. Jones, H. R. Froning, and E. E. Claytor, J. Chem. Eng. Data, 4, 85 (1959).