A chemical plant produces an ammonia-rich waste gas that cannot be released as-is into the environment. One method to reduce the ammonia concentration in the waste gas is to bubble the waste gas through a liquid solvent. Components of the gas that are highly soluble, like ammonia, will dissolve into the liquid phase. Water is an appropriate liquid solvent for this process.
The chemical plant produces 135.0 m3/hr of waste gas (? = 0.0407 mol/L) initially having a mole fraction of 0.130 NH3, and wishes to remove 90.0% of the initial amount of NH3. The maximum concentration of ammonia in water at this temperature is 0.5000 mol NH3/ mol water. Neglect the absorption of other waste gas components into the water, and the evaporation of water into the waste gas stream.
What rate is NH3 being removed from the feed gas?
What is the minimum flow rate of water (? = 0.990 g/mL) required to scrub out 90.0% of the incoming NH3?
What is the mole fraction of NH3 in the scrubbed waste gas stream?