(12 pts) Diesel-powered vehicles depend on a complex series of reactors to control their emissions. One of them reacts harmful NO and NO2 pollutants emitted by the engine with ammonia

(NH3) to form N2 and water. The reaction is called fast selective catalytic reduction (fast SCR): 2 \mathrm{NH}_{3}+\mathrm{NO}+\mathrm{NO}_{2} \rightarrow 2 \mathrm{~N}_{2}+3 \mathrm{H}_{2} \mathrm{O} The EPA limit for total nitrogen oxide (NO plus NO2) emissions at the outlet of there actor is 20 ppm. The flow into the SCR from the engine is composed by 78% N2, 2% O2, 10% CO2,10% H2O, 150 ppm NO and 150 ppm NO2 at a molar flow rate of 17 mol/min. The emission control system feeds an 32.5 wt% aqueous solution of urea(NH2CONH2) into the antechamber of the SCR reactor, where the urea is decomposed into ammonia and CO2 NH-CONH, + Н.О > 2NH, + CО,. The decomposition of urea is complete, and it results in a 10% excess of ammonia in the SCR reactor.

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