The liquid-phase reaction A R is being carried out in an adiabatic, ideal, CSTR. The reaction...

 

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The liquid-phase reaction A R is being carried out in an adiabatic, ideal, CSTR. The reaction obeys the rate equation -TA = kCA The value of the rate constant, k, is 0.05 L mol -1 h at 50 C and the rate constant has an activation energy of -1 80 kJ mol . The value of the heat of reaction, AHR, is -60 kJ mol 1 and is constant. The reactor operates at a space time, 7 of 2 h. The inlet concentrations are CA0 = 4 mol/L and CRO = 0 mol/L. The molar feed rate of A, FAO = 2000 mol/h. The heat capacity of the feed to the reactor is 3.4 J g K and the mass feed rate is 450000 g h. The feed temperature is 40 C. 1) How many possible operating points (xA,T) are possible at steady state? 1) What are the possible operating points (A,T) at steady state? If there are fewer than 3, enter "O" for the subsequent entries below: Steady-state 1: xA = K Steady-state 2: xA Steady-state 3: xA = %, T= %, T= K %, T K 2) Are any of the possible operating points unstable? Which ones? Explain your reasoning. Hint: Plot the rates of heat generation and heat removal vs. the reaction temperature and determine the points of intersection. The liquid-phase reaction A R is being carried out in an adiabatic, ideal, CSTR. The reaction obeys the rate equation -TA = kCA The value of the rate constant, k, is 0.05 L mol -1 h at 50 C and the rate constant has an activation energy of -1 80 kJ mol . The value of the heat of reaction, AHR, is -60 kJ mol 1 and is constant. The reactor operates at a space time, 7 of 2 h. The inlet concentrations are CA0 = 4 mol/L and CRO = 0 mol/L. The molar feed rate of A, FAO = 2000 mol/h. The heat capacity of the feed to the reactor is 3.4 J g K and the mass feed rate is 450000 g h. The feed temperature is 40 C. 1) How many possible operating points (xA,T) are possible at steady state? 1) What are the possible operating points (A,T) at steady state? If there are fewer than 3, enter "O" for the subsequent entries below: Steady-state 1: xA = K Steady-state 2: xA Steady-state 3: xA = %, T= %, T= K %, T K 2) Are any of the possible operating points unstable? Which ones? Explain your reasoning. Hint: Plot the rates of heat generation and heat removal vs. the reaction temperature and determine the points of intersection.