Optimal reactor network for methanol synthesis over Cu-Zn-Al catalyst has been developed by automated attainable regions analysis using the recursive convex control policy algorithm. Fundamental processes of solid catalyzed gaseous reaction, cooling, mixing and heating are considered in order to develop a reactor network that can be used to attain specific optimal conditions such as maximum conversion or minimization of the required heating or cooling surface area. Regions analysis is a process synthesis and optimization method that can be used develop optimal reactor networks by considering application onto the given feed, of all permitted processes that can be used to transform the feed to the required product