The work deals with optimization of the process of production of ethylbenzene by liquid-phase benzene alkylation. This process involves the reaction of benzene with ethylene to form ethylbenzene. Ethylene reacts with ethylbenzene to form undesired product di-ethyl benzene, if the temperatures of reactor or concentrations of ethylene are high. Di-ethyl benzene reacts with benzene to form ethylbenzene. Di-ethyl benzene is the highest-boiling component in the system; it comes out the bottom of two distillation columns. The recycling benzene is more expensive. The economic optimum steady-state design is developed that minimizes total annual cost. Thus it provides a classic example of an engineering design and optimization of a process. The purpose of this project is to develop an optimum design for the ethylbenzene process considering reactor size, benzene recycled
