Sulfuric Acid → Calcium Sulfate

Participants

Reaction Steps

One attempt to decrease the objectionable impurities obtained by the hydrolysis of epoxysuccinate to d,1-tartaric acid is described in U.S. Pat. No. 4,028,407 to Petritsch. In the approach toward purity of product taken by this patentee, tartaric acid was obtained by first epoxidizing calcium acid maleate in the usual manner with a tungsten acid-containing catalyst and reacting the resulting calcium acid epoxysuccinate with sulfuric acid to form a calcium sulfate and epoxysuccinic acid. An organic solvent is employed either alone or with water as a medium in which to react the calcium epoxysuccinate with sulfuric acid to obtain calcium sulfate and epoxysuccinic acid. The epoxysuccinic acid is hydrolyzed in the usual manner by boiling an aqueous solution at low pH to provide the desired tartaric acid.

Provenance & Evidence