Optimal operation of reactive simulated moving bed and Varicol systems

In this article, the performance of a reactive Simulated Moving Bed (SMB) and its modification, the more flexible Varicol process, is improved for the synthesis of methyl acetate (MeOAc) ester by multi-objective optimization using Non-dominated Sorting Genetic Algorithm (NSGA). The Varicol process is based on a non-synchronous shift of the inlet and outlet ports instead of the synchronous one used in the traditional SMB technology. The optimization problems considered are both twoand three-objective function problems. In one case, optimization was aimed at simultaneous maximization of the purity of MeOAc and minimization of adsorbent (and catalyst) requirement for the reactive SMB; while in the other case, maximization of purity and yield of MeOAc together with minimization of eluent (methanol) consumption for both reactive SMB and Varicol systems were considered. When the optimal solutions were compared, it was found that reactive Varicol systems could produce a higher purity product for a fixed yield, and consume slightly less eluent in the high purity region than more rigid SMB systems. # 2003 Society of Chemical Industry