Design and Optimization of Acetic Acid Dehydration Processes

Acetic acid is the most widely used aliphatic carbonic acid used as a reaction partner during the manufacture of acetic acid esters, or employed as a solvent in the production of cellulose acetate. Although acetic acid and water do not form any azeotrope, use of simple distillation to separate these two components is still not practical due to its high energy consumption rate. In this work, some separation designs that with high potential for energy saving for dehydration of acetic acid, such as multi-effect distillation, azeotropic distillation, and liquid-liquid extraction, etc., are investigated and analyzed in detail. It shows that the liquid-liquid extraction with methyl tert-butyl ether (MTBE) as extraction agent is the most promising separation method in this system due to its lower energy consumption and the total annual cost (TAC).