PROCESS FOR THE PREPARATION OF MALEIC ANHYDRIDE

摘要

In the production of maleic anhydride, scale formation in an evaporator and pipes is a very difficult problem. By the process disclosed herein, scale formation in a maleic anhydride preparation apparatus can satisfactorily be prevented, and therefore, maleic anhydride preparation apparatus can be operated continuously for a long period. Further, it is also possible to significantly reduce the formation of fumaric acid. The process is that when conducting the concentration and the dehydration of an aqueous solution of maleic acid, a small amount of hydrogen peroxide is added to the aqueous solution. Scale is formed by condensation of phenols and aldehydes, and quinones and aldehydes. Hydrogen peroxide added acts to oxydize aldehydes contained in the aqueous solution.