The Arrhenius Equation is Still a Useful Tool in Chemical Engineering

The Arrhenius equation correlates the rate of a chemical reaction with the corresponding activation energy, reaction time and reaction temperature, where the latter is measured in Kelvin. Although the equation is rather simple it can be used to summarize the kinetics of most chemical reactions in a surprisingly good manner. The activation energy is an interesting parameter that can be seen as an energy barrier which the reacting chemicals have to pass before a chemical reaction is initiated. Thus, the higher the activation energy, the lower is the rate of the chemical reaction. Moreover, the equation can also be used, for example, to forecast the influence of a higher temperature on the composition of a product consisting of components with different activation energies. In such a case, a component with higher activation energy will increase its rate of reaction more than a component with lower activation energy. The composition of the original product will thus obtain a shrinking fraction of the fast reacting component. The report gives some guidelines of how to calculate the activation energy for a given case in a pulp mill.