FEATURES OF ALCOHOLYSIS OF FATTY ACID METHYL ESTERS BY TRIMETHYLOLPROPANE

This study analyses the kinetic relationships involved in the transesterification of trimethylolpropane (TMP) and fatty acid methyl esters (FAMEs) derived from vegetable oil to produce biodegradable lubricating oils, based on scientific literature. The work presents the most favourable conditions for the process. In the classical vision of the transesterification process between polyhydric alcohol and methyl esters of fatty acids, a number of inaccuracies have been identified based on theoretical concepts. It is argued that the mechanism of classical sequential parallel reversible processes in the synthesis of mono-, di-, and tri-substituted derivatives of trimethylolpropane and methyl esters of fatty acids can be complemented by certain features. Trimethylolpropane monoester is believed to act as an acyl group carrier, forming the corresponding trimethylolpropane di- and triesters. Additionally, intermolecular interactions expand the classical mechanism of series- parallel reactions. It is suggested that intermolecular interactions between metabolites of 'classical' reactions are possible. In this case, it is difficult to identify these reactions in the overall process as no additional products are formed. The reaction mechanism scheme involving trimethylolpropane monoester showed that the reaction is endergonic and non-spontaneous, indicating that the entire transesterification process is endergonic. Additionally, the work demonstrates the correlation between the likely spatial configuration of trimethylolpropane, its intra- and intermolecular hydrogen bonds, and the Gibbs energies data obtained from literature. The paper presents the overall reaction schemes of the process and the structure of trimethylolpropene anions. It also illustrates a plausible scenario for the interaction of intermediate products, while indicating potential intermediates in all reactions.