There is a certain trade-off between fast reaction kinetics and an economic operation of the reactive distillation process.High excesses of alcohol and large amounts of catalyst will lead to very fast reaction rates. In contrast to these requirements an economic process requires low catalyst amounts because the catalyst has to be neutralized in a subsequent process step. Additionally, high amounts of sulphuric acid lead to corrosion, and thus to high investment costs. Furthermore,the stoichiometric ratio of alcohol to acid should be low to reduce the amount of alcohol, which is directly linked with the separation and raw material costs.
The influence of the amount of the catalyst sulphuric acid on the conversion of oleic acid is shown in Fig. 3. In the diagram the conversions are normalized to the conversion of oleic acid of the experimental run with ωcat = 0.015 gcatalyst goleic acid −1 .