4. 1,1-dichloroethane (DE) is removed from air by adsorption to activated carbon. Air containing DE at 40C with a dew point of 12C is fed to an adsorber. Activated carbon is fed at a rate of 2 kg/min. The activated carbon is reused so when it is fed to the adsorber it already contains 50g DE per kg of activated carbon. Leaving the adsorber it contains 300 g DE per kg of activated carbon. The pressure of entering and exiting air is 770 mmHg. The equilibrium relationship follows the Freundlich model, y=0.089p0.51 where y is the g of DE adsorbed per g of activated carbon and p is the partial pressure of DE in the gas phase in mmHg. a. Calculate the mass fraction of DE in the air exiting the adsorber, assuming the exit air is in equilibrium with the exiting activated carbon. b. Calculate volumetric flow rate (m3/min) of bone dry air pass through the process