This paper presents the superstructure-based mixed-integer non-linear programming approach to the synthesis of reactor networks in an equation-oriented environment, The model comprises a general superstructure in which the exact formulation of the recycle reactor (RR) and a continuous stirring tank reactor (CSTR) are embedded so as to enable a different feeding (cross flow, side stream), recycling and bypassing. The reactor arrangement is capable of representing several reactor systems such as a pure CSTR, a pure plug Row reactor, pure RR, their combinations and also a cross flow reactor. The superstructure is suitable either for an isothermal or non-isothermal, simple or complex reactor network. With the multilevel-hierarchical strategy, it is possible to postulate the superstructure at different levels of representation of flowsheet alternatives. Therefore, the superstructure is optimized more effectively and reliably. The approach has been applied to a complex non-isothermal reaction problem - an industrial example of the production of allyl chloride.