Solid acid catalysed esterification of amino acids and other bio-based acids

Esters represent an important class of chemical compounds with applications as solvents, plasticizers, flavors and fragrances, pesticides, medicinals, surfactants, chemical intermediates, and monomers for resins. Recently, esters of amino acids have attracted attention regarding their use as biobased surfactants with excellent adsorption and aggregation properties, low toxicity, and broad biological activity. Although scattered information is available on amino acid and other acid esterification, detailed kinetic and thermodynamic data for many systems have not been developed to date. We present here some useful data pertaining to kinetics and reaction equilibria for the esterification of various acids using strong cationic exchange resins. Ion exchange resins offer high acidity and ease of separation as advantages over conventional mineral acids for esterification.