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Andrea Landella POLITECNICO DI MILANO Industrial Organic Chemistry Exam Jan 17, 2018 Consider a double stage adiabatic reactor, with intermediate cooling, for methanol production: R-101 R-102 Equilibrium E-101 F1,y1,T1 F0,y0,T0 F2,y2,T2 F3,y3,T3 Q The inlet to R-101 is a mixture of H2/CO/CH4 at 190°C and 100 atm, with H2/CO = 3.75 and CH4/CO = 0.25. The heat exchanger E-101 is ideal, with unitary efficiency. The second reactor R-102 is at equilibrium, while R-101 has a CO conversion of 35%, and the overall CO conversion is 50%. Assuming ideal mixture of perfect gases, with negligible Poynting correction and negligible pressure drops, it is required to evaluate: The minimum number of required chemical reactions in the reactor: The degree of advance of the first reactor λ1 and the outlet composition y1; The temperature at the outlet of R-101, or T1; The temperature at the outlet of E-101, or T2, and the heat exchanged Q; The degree of advance of the second reactor λ2, and the outlet temperature T3; Andrea Landella POLITECNICO DI MILANO DATA: The available data are the equilibrium constant of the methanol synthesis, all the temperatures are in Kelvin: 2 5 2 9 3 12 4 9.8585ln 1.0362 10 1.5137 10 7.4889 101( ) 25722.614 exp 1.987 1.4359 10 18376.875 / 3.5356 eq T T T TKT TT − − − −  − −  +  − =   +  + −  The reference state for calculation of the activities is the perfect gas at 1 atm. Heat capacities vary with temperature, and are expressed as follows: 2 3 4()Cp T A BT CT DT ETR = + + + + the molar enthalpies of formation in the reference state are listed for each reactive specie in the following table, together with the Heat capacity constants: Specie Δfh0(298 K) [cal/mol] A B×103 C×105 D×108 E×1011 CO -26405,617 3.912 -3.913 1.182 -1.302 0.5155 H2 0…