LearnChemE

Thermal Effects in Chemical Reactions: Interactive Simulation

This simulation was prepared using Mathematica. Download the free Wolfram player, and then download the simulation CDF file (link given below or click on figure to download). Try to predict the behavior when a parameter changes before using a slider to change that parameter. A screencast below explains how to use this simulation.

A reversible reaction, A↔B, takes place in an adiabatic plug-flow reactor (PFR). Select either an exothermic (ΔH < 0) or an endothermic (ΔH > 0) reaction. The black curve is the equilibrium conversion as a function of temperature from the van’t Hoff equation. The blue line is conversion as a function of temperature from the adiabatic energy balance. The intersection of the curve and the line is the conversion at equilibrium (Xe) and the adiabatic temperature at equilibrium (Te). You can vary the feed temperature and the molar ratio of inert to reactant in the feed.

Try to answer these questions before determining the answer with the simulation. We suggest that you write down the reasons for your answers.

  1. For an endothermic reaction in an adiabatic reactor, how does the equilibrium conversion change when inert is added to the feed?
  2. For an exothermic reaction in an adiabatic reactor, how does the equilibrium conversion change when the feed temperature increases?