K1 k 1 from below as t increases exothermic e 1 e1 0

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Unformatted text preview: or? Effect of Temperature on Equilibrium Performance of Batch Reactor T0 specify temperature nj (t) Conversion of species A: Rate of produc!on species A: CA = nA /VR A k1 ⌦ k-1 Conserva!on of mass: B At Equilibrium: RA = 0 = n A0 n A x= n A0 RA = k1 CA + k-1 CB NA (t) + NB (t) = NA0 k1 CAeq + k-1 (CA0 k1 (1 1 xeq ) = xeq Keq CAeq ) xeq ) = k-1 xeq Func7on of temperature Thus at equilibrium, the conversion of species A is (1 x=1 CA CA0 Keq k1 = k-1 Effect of Temperature on Equilibrium of Batch Reactor (ii) A k1 ⌦ k-1 B (1 xeq ) = 1 xeq Keq As T increases slope get larger, more A formed exothermic increasing T Keq 1 x Keq k1 = k-1 Slope depends on temperature increasing T endothermic (1 x) As T increases slope get smaller, and conversion increases; more B formed xeq 0 0 k1 k1 Keq = 0 exp[ (E1 E-1 )/RT ] = 0 exp[ H/RT ] k-1 k-1 0 endothermic: E1 > E-1 Keq ! k1 /k-1 from below as T increases exothermic: E-1 > E1 0 Keq ! k1 /k-1 from above as T increases H>0 H<0 Op7mal Temperature in a Batch Reactor T0 nj (t) specify temperature RB = k1 (1 x) 0 k1 = k1 exp( E1 /RT ) 5.6 B x=0.56 5.5 RB A 0 k-1 = k-1 exp( E-1 /RT ) H < 0 (exothermic) CA = nA /VR k1 ⌦ k-1 k-1 x Rate of produc7on of species B 5.4...
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This document was uploaded on 03/14/2014.

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