Patent ID: 8569539

Claim:
A continuous process for preparing an alpha-hydroxycarboxylic ester, comprising: reacting an alpha-hydroxycarboxamide with an alcohol in the presence of the catalyst to obtain a product mixture which comprises the alpha-hydroxycarboxylic ester, ammonia, the alpha-hydroxycarboxamide, the alcohol, and the catalyst; wherein a) reactant streams comprising, the alpha-hydroxycarboxamide, the alcohol and the catalyst are fed into a pressure reactor; b) the reactants are reacted with one another in the pressure reactor at the pressure of from greater than 1 bar to 100 bar to form the product mixture; and c) the ammonia in the product mixture is depleted by distilling off ammonia and alcohol at a pressure which is less than the pressure of the reaction and greater than 1 bar without an addition of a stripping media.