Abstract: Sequential multipurpose batch processes are common in many fine chemical manufacturing plants, such as traditional paint, food, pharmaceuticals,and specialty chemicals plants. The investigation in this paper includes analyzing the operational features of sequential multipurpose batch plants, decomposing the overall batch process spatially into several sub-systems, and presenting a modified MILP formulation for the scheduling of sequential multipurpose batch plants with continuous-time approaches. As the bi-index binary variables are substituted for the tri-index binary variables in the MILP model, the number of discrete variables decreases substantially. The new model is effective in solving large scale scheduling problems. In case studies, the proposed model was compared with the previous model presented by Voudouris and Grossmann. Moreover, several large scale scheduling problems were solved successfully with the proposed modeling approaches. These case studies prove the validity of the model and the practicability of the proposed approaches.