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CRE – 28.09.15 - Exam C 1 096116 Chemical Reaction Engineering 28 September 2015 Family name _________________________________________________ First name _________________________________________________ ID number _________________________________________________ Signature _________________________________________________ Please, consider that the sum of perc entages of proposed exercises (5 ) is equal to 110%. This means that the maximum mark you can reach is 33. Remember to write on the top of each sheet you submit: your name, ID number, and signature. Use of mobile phones and internet connection is not allowed. 1. Second order reaction in a CSTR (25%) The following second-order liquid-phase reaction is taking place in a CSTR: 𝐴𝐴+ 𝐵𝐵→ 2𝐶𝐶+ 𝐷𝐷 A and B are fed to the reactor at rates of 3 mol/min and 1 mol/min respectively at a temperature of 300 K. The total volumetric flow rate is 5 l/min. Specific heats (in J/mol/K) of A, B, C and D are 125, 100, 130 and 135 respectively. The reactor is jacketed by water at a temperature of 40°C . The overall heat transfer coefficient has been estimated at 200 J/m2/s/K, while the heat transfer area is 0.5 m2. Mixing is ensured through an agitator, which contributes a work of 10 kW to the reactor. The heats of formation of A, B, C and D (at 298 K) are -45 kJ/mol, -30 kJ/mol, -50 kJ/mol and -60 kJ/mol respectively. The rate constant at 300 K is 0.1 l/mol/min and the activation energy is 30,000 J/mol. Find the steady-state temperature in the reactor for 90% consumption of the limiting reactant. Find the volume of the reactor to achieve this conversion. 2. Consecutive reactions in a batch reactor (20%) The following liquid-phase consecutive reaction is taking place in a constant volume batch reactor. 𝐴𝐴 𝑘𝑘1 → 𝐵𝐵 𝑘𝑘2 → 𝐶𝐶 The first…