Cumene (C₆H₅C₃H₇) is produced by reacting benzene with propylene [?H?_r (77?F) = ? 39.520 Btu/lb-mole]. A liquid feed containing 75 mole% propylene and 25% n-butane and a second liquid stream containing essentially pure benzene are fed to the reactor. Fresh benzene and recycled benzene, both at 77?F, are mixed in a 1:3 ratio (1 mole fresh feed f3 moles recycle) and passed through a heat exchanger, where they are heated by the reactor effluent before being fed to the reactor. The reactor effluent enters the exchanger at 400?F and leaves at 200?F. The pressure in the reactor is sufficient to maintain the effluent stream as a liquid. After being cooled in the heat exchanger, the reactor effluent is fed to a distillation column (Ti). All of the butane and un-reacted propylene are removed as overhead product from the column, and the Cumene and un-reacted benzene are removed as bottoms product and fed to a second distillation column (T2) where they are separated. The benzene leaving the top of the second column is the recycle that is mixed with the fresh benzene feed. Of the propylene fed to the process. 20% does not react and leaves in the overhead product from the first distillation column. The production rate of Cumene is 1200lb_m/h.

(a) Calculate the mass flow rates of the streams fed to the reactor, the molar flow rate and composition of the reactor effluent, and the molar flow rate and composition of the overhead product from the first distillation column T₁

(b) Calculate the temperature of the benzene stream fed to the reactor and the required rate of heat addition to or removal from the reactor. Use the following approximate heat capacities in your calculations: C_p [Btu/lb_m??F)] = 0.57 for propylene, 0.55 for butane. 0.45 for benzene, and 0.40 for Cumene.

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REACTOR Propylene Butane 77°F Benzene 77°F 400°F HEAT EXCHANGER 200°F 7°F Propylene Butane Benzene FH DISTILLATION COLUMNS Cumene