Abstract The main goal of this research is modeling and optimal control of ethylbenzene dehydrogenation reactors to obtain optimal dynamic trajectories of feed temperature and steam flow rate to achieve maximum process performance. In this regard, a pseudo dynamic model is developed for ethylbenzene dehydrogenation reactors based on the mass and energy balance equations considering catalyst deactivation. The process consists of three radial flow reactors, equipped with inter-stage heat exchangers to manipulate feed temperature. To develop an accurate model, a catalyst decay model is selected and the parameters of considered model is calculated based on the plant data. After model validation, a dynamic optimization problem is formulated to achieve maximum styrene capacity and uniform production level as objectives, considering feed temperature and inlet steam flow rate as decision variables. To calculate the optimal trajectory of decisions, a quadratic time dependent correlation is considered for each decision variable and optimal values of coefficients are determined based on the formulated optimization problem. The simulation results show that feed temperature and inlet steam flow rate should be increased gradually during the process run time. It is appeared that, production capacity is improved about 26.42% compared to the conventional condition.