Acetic acid recovery

In a process for the manufacture of N-formyl aspartic anhydride via the reaction of aspartic acid, formic acid, acetic anhydride in which crystals of N-formyl aspartic anhydride are formed and separated from a mother liquor which includes quantities of acetic acid, formic acid, acetic anhydride, formic acetic anhydride and high boiling aspartic acid derived components, the improvement comprising:

• (a) separating said high boiling aspartic acid derived components from said mother liquor;
• (b) heating said mother liquor to a temperature greater than or equal to about 70.degree. C. for a time period ranging from about 1 hour to about 24 hours to convert all of said formic acetic anhydride to acetic acid and gaseous carbon monoxide and to fully deplete either said acetic anhydride or said formic acid, whichever is initially present in a stoichiometric lesser amount and thereby produce a mixture comprising acetic acid and either acetic anhydride or formic acid, whichever has not been depleted;
• and
• (c) separating acetic acid initially present in the mother liquor and acetic acid formed in step (b) from the remainder of said mixture produced in step (b).