New processes for recovery of acetic acid from waste water

This paper addresses an industrially important problem of acetic acid recovery from a waste water stream via reactive distillation. The presence of a three-phase regime on the column stages due to a liquid–liquid phase split between aqueous and organic phases is a typical characteristic of this process. A modern modeling approach is presented to detect the existence of potential phase splitting in this column. A good agreement of a phase splitting model with the literature data has been shown. A theoretical study for the recovery of acetic acid from its 30 wt% aqueous solution by esterification with n-butanol is presented. Alternate column structures were investigated and two structures rendering theoretically close to 100% conversion of acetic acid were identified. The dynamic simulations were performed on proposed structures to see transient responses wrt. to common process disturbances. The work was originally presented at the PRES-2006 (27–31 August) conference in Prague, Czech Republic.