(a) Ammonia gas is being absorbed by water in a wetted-wall column. At one level of the column, the following data applies: gas-phase mass transfer coefficient 5.22 × 10-9 kmol m-2 s-1 Pa-1 liquid-phase mass transfer coefficient 3.88 × 10-5 m s-1 Henry's constant 0.955 kPa (kmol m-3)-1. Estimate the overall mass transfer coefficient KL.
(b) What is the ratio of the individual mass transfer resistances in Question 2 (a)?
(c) Use the following additional information to find the mass transfer flux in the column: mole fraction of ammonia in liquid* 1.351 × 10-3 mole fraction of ammonia in gas* 0.065 total pressure of system 1.013 bar mole mass of ammonia 17 *Note: these values will need to be converted to concentrations in kmol m-3.
(d) What is the partial pressure of the ammonia gas at the gas/liquid interface?
(e) What is the molar concentration of the ammonia in the liquid at the interface?