| abstract |
The continuous process for preparing alpha-hydroxycarboxylic esters, in which the reactants reacted are alpha-hydroxycarboxamide with an alcohol in the presence of a catalyst to obtain a product mixture which comprises alpha-hydroxycarboxylic ester, ammonia, unconverted alpha-hydroxycarboxamide, and also alcohol and catalyst; wherein reactant streams comprising, as reactants, an alpha-hydroxycarboxamide, an alcohol and a catalyst are fed into a pressure reactor; the reactant streams are reacted with one another in the pressure reactor at a pressure in the range from 1 bar to 100 bar; and the product mixture is depleted in alcohol and ammonia, wherein ammonia is distilled off at a pressure which is constantly kept greater than 1 bar without the aid of additional stripping media. The continuous process is particularly advantageously employable on the industrial scale. |