The research progress on the esterification reaction of dicarboxylic acids

In modern chemical industry, dicarboxylic acid esters, as an important class of organic synthesis intermediates and fine chemicals, hold significant application value in fields such as chemical engineering, pharmaceuticals, and food. This paper provides a comprehensive review of the selection of catalysts for the preparation of dicarboxylic acid esters via the Fischer esterification method, the in-depth understanding of the reaction mechanism, and the optimization of process flows. The performance of various catalysts is discussed in detail, including homogeneous and heterogeneous catalysts in thermocatalytic systems, as well as emerging enzymatic and photocatalytic technologies. Moreover, the catalytic mechanisms of these systems are elaborated to offer theoretical support for precise control of the reaction process. In addition, several process optimization strategies are introduced, including continuous processing, reactive distillation, and membrane-assisted operations, all of which have significantly enhanced the efficiency and product quality of the esterification reactions. Finally, considering current advancements in reaction intensification technologies and process engineering, this paper highlights that efficiently coupling these intensification techniques with reactive distillation and developing more efficient solid acid catalysts are key directions for future research.