How Is Fumaric Acid Manufactured?

Fumaric acid is a valuable compound used in foods, beverages, detergents, animal feed, pharmaceuticals and miscellaneous industrial products. 

Chemical Synthesis: The chemical synthesis of fumaric acid involves the conversion of maleic anhydride to maleic acid, which is then converted to fumaric acid through a transesterification reaction. The process begins with the addition of maleic anhydride to a solution of methyl alcohol in water. The mixture is heated at a high temperature for several hours until the alcohol is completely consumed and the maleic anhydride is reduced to maleic acid.

Next, the maleic acid is treated with sulfuric acid to convert it into a bisulfonic acid. The resulting product is then subjected to a transesterification reaction with ethyl alcohol in water to produce fumaric acid.

Fermentation: Fermentation is another method of producing fumaric acid. This method involves the use of microorganisms such as Aspergillus oryzae to convert sugars into alcohols and acids. The fermentation process starts with the addition of sugar to a solution of yeast extract in water. The yeast ferments the sugars and produces alcohol and carbon dioxide.

The carbon dioxide is removed from the solution, and the remaining liquid is called a "fermenter's liquor". The fermenter's liquor contains both alcohol and acid, which are separated using various techniques such as distillation or filtration.

The alcohol is then treated with sulfuric acid to convert it into a bisulfonic acid, which is then subjected to a transesterification reaction with ethyl alcohol in water to produce fumaric acid.

Both chemical synthesis and fermentation have their advantages and disadvantages. Chemical synthesis is more efficient but requires expensive equipment and materials, while fermentation is cheaper but requires more time and labor.

In conclusion, fumaric acid can be produced by either chemical synthesis or fermentation. Both methods have their own advantages and disadvantages, and the choice of method depends on the specific application and cost constraints.