Hydrocarboxylation of methylene dipropionate in the presence of propionic acid and a heterogeneous catalyst

摘要

Disclosed is a process for the production and purification of glycolic acid or glycolic acid derivatives by the carbonylation of methylene dipropionate in the presence of a solid acid catalyst and propionic acid. This invention discloses hydrocarboxylations and corresponding glycolic acid separations wherein the propionic acid stream is readily removed from the glycolic acid and the propionic acid is recycled.