Graphical Analysis of Equilibrium-Limited Adiabatic Reactors

4 Graphical Analysis of Equilibrium-Limited Adiabatic Reactors 

Suppose we are asked to analyze the behavior of a single reaction, taking place in an adiabatic reactor. One of the questions we might want to answer is What is the maximum conversion that can be achieved Of course, the maximum conversion is obtained when the reaction reaches chemical equilibrium. 

If there is a large amount of catalyst in the reactor, and if the catalyst is very active, the reaction might be close to equilibrium at the reactor effluent conditions. The assumption that equiUbrium is achieved provides an upper limit on conversion, and either an upper or lower limit on temperature, depending on whether the reaction is exothermic or endothermic. In this example, the outlet composition will correspond to a fractional SO2 conversion of 0.74, and the outlet temperature will be 593 °C, i/equilibrium is achieved at the outlet conditions of the reactor. 

These five equations, which were introduced in Chapter 2, permit the equilibrium constant, Kgq, to be calculated at any temperature. The equilibrium conversion, Xeq, then can be calculated from the equilibrium expression  

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