PROCESS FOR PREPARING 3-HYDROXYCARBOXYLIC ACIDS

Disclosed is a process for hydrating an alpha, beta-unsaturated carboxylic acid, such as acrylic acid, in water, in the presence of a catalyst selected from carbon dioxide, a sulfur oxide, a nitrogen oxide, gaseous hydrochloric acid, an inorganic or organic base having a pKa greater than 7, to prepare a 3-hydroxycarboxylic acid such as 3-hydroxypropionic acid. Also disclosed is a process for recovering 3-hydroxypropionic acid from a solution comprising the 3-hydroxypropionic acid. La presente invencion describe un proceso para hidratar un acido carboxilico alfa, beta-insaturado, tal como el acido acrilico, en agua, en la presencia de un catalizador seleccionado de dioxido de carbono, un oxido de azufre, un oxido de nitrogeno, acido clorhidrico gaseosos, una base organica o inorganica que tiene una pKa mayor que 7, para preparar un acido 3-hidroxicarboxilico tal como el acido 3-hidroxipropionico. Tambien se describe un proceso para recuperar el acido 3-hidroxipropionico de una solucion que comprende el acido 3-hidroxipropionico.