Question

A packed column uses an amine solution to absorb 90% of carbon dioxide from a gas phase. The entering gas contains 5 mol% carbon dioxide, and flows at 600 mol h-1. Theamine solution enters the column at a flow rate of 900 mol h1 with no carbon dioxide. The gas-liquid equilibrium composition (for mole fraction of carbon dioxide in gas, y, and liquid,x) is given by y 0.6x. The cross sectional area of the column is 3.5 m² and the overall mass transfer coefficient in gas phase, Ka, is 40 mol m-3 h1. (a) Find the compositions of leaving gas and leaving amine solution. (b) Using the trapezoidal rule with five equal divisions, calculate the number of transfer units required for this process. (c) Determine the height of the packed column.

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