Dichloromethane and chloroform are being stripped from water into air at 1.2 \(\mathrm{atm}\) and \(25.0^{\circ} \mathrm{C}\). Feed water contains \(1000.0 \mathrm{ppm}(\mathrm{mol})\) of chloroform and \(2000.0 \mathrm{ppm}\) (mol) of dichloromethane. We want a \(99.99 \%\) or better removal of both solutes-design for \(99.99 \%\) removal of the solute that is more difficult to remove. Water flow rate is \(200.0 \mathrm{kmol} / \mathrm{h}\) and can be assumed constant. Air flow rate is \(25.0 \mathrm{kmol} / \mathrm{h}\) and can be assumed constant. Entering air is pure at \(25.0^{\circ} \mathrm{C}\) and \(1.2 \mathrm{~atm}\). Data are in Table \(12-2\)

a. Find the outlet mole fractions of chloroform and dichloromethane in both gas and liquid.

b. Find the number of equilibrium stages required in the stripper.

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TABLE 12-2. Henry's law constants for Eq. (12-3) and solubilities for chlorinated compounds in water at 25.0C and 1.0 atm (Yaws et al., 2005) Compound Carbon Chloroform Dichloro- Vinyl 1,2,3,- 1- 1-Chloro- methane chloride Trichloro-Chloro- naphthalene CH2Cl2 C2H2Cl propane heptane C 10H7Cl C3H5Cl3 C7H15Cl tetra- chloride CHCl3 CCl4 atm H 1589.36 211.19 137.00 1243.84 23.78 2130.28 10.96 mole frac. Solubility, 93.68 1190.1 ppm (mol) 4175.4 778.9 213.99 1.8196 2.48