OP-II-3

OP-II-2ENTRAINER BASED REACTIVE DIVIDED WALL COLUMNSThotla S. 1 , Freund H. 1 , Sundmacher K. 1,2*1 Max Planck Institute for Dynamics of Complex Technical Systems, s,Magdeburg, Germany2 Process Systems Engineering, Otto-von-Guericke University,Magdeburg, Germany, * E-mail: sundmacher@mpi-magdeburg.mpg.deA reactive divided wall column (RDWC) integrates reactive distillation (RD) anddownstream distillation into a single unit, which offers various advantages [1]. In caseof non ideal vapor-liquid equilibrium (VLE), the mole ratio of reactants fed to the RDcolumn depends on the azeotropic composition of the reactant(s) with the product(s)and the mutual solubility. In such cases, an azeotropic or an extractive distillation isrequired to further recover the reactant(s) and/or product(s). The case of using anentrainer in RD has already been analyzed [2] with the aim of maintaining the temperaturein the reactive zone below the maximum allowable temperature for thecatalyst.In the present study, the use of a RDWC as a multifunctional reactor whichperforms both operations, i.e. RD and azeotropic distillation, is investigated. Twodifferent entrainer based RDWC (i.e. EBRDWC) configurations for industriallyimportant products such as ethyl acetate (EA) and n-propyl propionate (NPP) havebeen studied in detail by simulations. The EBRDWC configuration for EA production(Fig. 1) has a common top rectifying section which refluxes liquid to both sides of thedividing wall. In this case, EA itself acts as an entrainer. An NRTL VLE model and aconcentration based kinetic model [3] have been used in the simulations. The effectof various operating parameters such as the reboiler duty, the number of reactive andnon-reactive stages, common rectifying stages and the liquid split ratio have beenstudied to conceptually design the EBRDWC. The feasibility of a RDWC mainlydepends on the pressure and temperature profiles on either sides of the dividing wall25625EthanolAcetic acidWaterEAFig. 1: EBRDWC for EA productionStage number191371RD sideEtOHAAEAwater0 0.5 1Mole fractionAzeotropicside10.0 0.5 1.0Mole fraction(a)5Stage number432Stage number19137RD sideAzeotropicside10 0.5 1(b) T/TmaxFig. 2: (a) composition (b) temperature profiles of feasible EBRDWC100