Q1. A CSTR is used to produce a desired product C. The reactants, A and B,...

 

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Q1. A CSTR is used to produce a desired product C. The reactants, A and B, are kept in two separate storage tanks. In the tanks the reactants are stored at high concentration at 5 and 8 mol/L for A and B respectively. These concentrations are safe for storage but are too high to conduct the reaction safely. To manage this, the reactant feed streams are mixed with a pure water feed stream before the inlet of the reactor. Into this mixer, the flowrates are: Pure water, 100 L/min Reactant A from storage, 2 L/min Reactant B from storage, 5 L/min In the reactor, there are two significant reactions: A desired reaction: A (aq) + 2B (aq) 2C (aq), An undesired side reaction: C (aq) + D (aq) E (aq) (1) (2) The density of the solution Both reactions are irreversible. Reaction 1 is elementary and has a rate constant of 1.5 L2/mol.min. The concentration of water (D) is almost constant. This means that the rate expression for reaction 2 can be expressed as first order with respect to C (only) with a rate constant of 0.8 min (when in water). The reactor volume is 4000 L. Determine: a) i. the concentration of A, B, C, and E at the outlet (D is water). ii. the yield of C per mole of A. iii. the selectivity of C (as a ratio to E). This requires numerical solving of equations in Excel or Python. Attach your clear and annotated code/spreadsheet you use to do the solving. b) If the flowrate of B is doubled, what are the new concentrations, yield, and selectivity. Since this is an update of part (a), be clear about what equations and/or values change (if any). Give the results with your main working and attach the updated code/spreadsheet. (hint: extent of reaction is a better choice than conversion due to multiple reactions). Q1. A CSTR is used to produce a desired product C. The reactants, A and B, are kept in two separate storage tanks. In the tanks the reactants are stored at high concentration at 5 and 8 mol/L for A and B respectively. These concentrations are safe for storage but are too high to conduct the reaction safely. To manage this, the reactant feed streams are mixed with a pure water feed stream before the inlet of the reactor. Into this mixer, the flowrates are: Pure water, 100 L/min Reactant A from storage, 2 L/min Reactant B from storage, 5 L/min In the reactor, there are two significant reactions: A desired reaction: A (aq) + 2B (aq) 2C (aq), An undesired side reaction: C (aq) + D (aq) E (aq) (1) (2) The density of the solution Both reactions are irreversible. Reaction 1 is elementary and has a rate constant of 1.5 L2/mol.min. The concentration of water (D) is almost constant. This means that the rate expression for reaction 2 can be expressed as first order with respect to C (only) with a rate constant of 0.8 min (when in water). The reactor volume is 4000 L. Determine: a) i. the concentration of A, B, C, and E at the outlet (D is water). ii. the yield of C per mole of A. iii. the selectivity of C (as a ratio to E). This requires numerical solving of equations in Excel or Python. Attach your clear and annotated code/spreadsheet you use to do the solving. b) If the flowrate of B is doubled, what are the new concentrations, yield, and selectivity. Since this is an update of part (a), be clear about what equations and/or values change (if any). Give the results with your main working and attach the updated code/spreadsheet. (hint: extent of reaction is a better choice than conversion due to multiple reactions).