DFT Study of Transesterification and Hydrolysis of the Fatty Acid Triglycerides, Carried Out under Supercritical Fluid Conditions. Analysis of Thermochemistry and Kinetics

Abstract

By quantum-chemical simulation using DFT method with B3LYP density functional and basis 6-311++g(df, p) in the implementation of the program Gaussian16 and subsequent comparison with calculations data, obtained by using density functional wB97XD/6-311++g(df, p), mechanism of reactions of transesterification and hydrolysis of fatty acid triglycerides, carried out under supercritical fluid conditions has been investigated. The energy characteristics of the elementary acts of potential steps for Supercritical Fluid (SCF) conditions has been calculated, their thermochemical analysis has been given, the rate constants of elementary acts for the temperature range 300-623 K has been investigated. It is shown that under supercritical fluid conditions, transesterification and hydrolysis of fatty acid triglycerides with dimer and trimer associates of alcohol and water in various combinations can proceed by one-step and two-step mechanism.

Closed-loop utilization of polyester in the textile industry

“…The BHET melt could also undergo a polycondensation process to afford recycled PET (r-PET). This polycondensation process, however, has to overcome a higher barrier of 26.9 kcal mol −1 (ΔH polym , enthalpy of the transition state of condensation reaction, 43 Fig. 3b).…”