A mixture of 3 mol% CO$_2$ and 2 mol% of NH$_3$ is contacted with a slightly caustic water solution (assume the caustic solution has the properties of pure water) in an absorber. A 97% absorption of CO$_2$ is needed. The air-flow rate is 5,000 ft$^3$/minute at 60$^\circ$F and 1 atm. It may be assumed that the equilibrium curve for CO$_2$ is $X_{\text{CO}_2,\text{G}}^*=1.75 X_{\text{CO}_2,\text{L}}$ where $X$ is the mole ratio of CO$_2$ to CO$_2$-free carrier. The NH$_3$ solubility follows Henry's law, $P_{\text{NH}_3,\text{G}} = H x_{\text{NH}_3,\text{L}}$, where the partial pressure of ammonia in the gas is proportional to the molar fraction in the liquid phase, and $H=2.7$ atm/mole fraction. A 90% absorption of ammonia is needed. Using the network modeling approach covered in this course, address the items to follow (based on Seader, Henly, and Roper textbook Separation Process Principles Chap. 6, 2016). ¶