Activity Coefficients for Liquid Organic Reactions: Towards a Better Understanding of True Kinetics with the Synthesis of Jasmin Aldehyde as Showcase

• Published in: International journal of molecular sciences Vol. 20; no. 15; p. 3819
• Main Author: Heynderickx, Philippe M
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 05.08.2019; MDPI
• Subjects: Activity coefficients; Alcohol; Aldehydes; Aldehydes - chemical synthesis; Aldehydes - chemistry; Algorithms; Byproducts; Carbon; Condensates; Equilibrium; Ethanol; Initial conditions; Inspection; Kinetic coefficients; Kinetics; liquid reactions; modelling; Models, Chemical; Parameter estimation; Reaction kinetics; Reaction time; Solvents; Temperature; activity coefficients; parameter estimation; modelling; liquid reactions
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms20153819

The aldol condensation of benzaldehyde and heptanal is taken as an example of reversible liquid phase organic reactions to show that inclusion of activity coefficients reveal distinct differences in conversion and product distribution when different solvents methanol, ethanol, n-propanol, or n-butanol are used. The purpose of this work is to show a pronounced solvent effect for a given set of identical kinetic parameters, i.e., the same liquid phase kinetics can result in different conversion and yield values, depending on the choice of solvent. It was shown that subsequent parameter estimation without inclusion of the activity coefficients resulted in a pronounced deviation from the 'true' kinetics, up to a factor of 30. It is proposed that the usage of average activity coefficients gives already a significant improvement, resulting in acceptable parameter estimates.