Catalytic reforming of naphtha is one of the important processes for converting the naphtha with low octane number to high octane number gasoline. One the main problems in this process are deactivation of its catalysts. The catalytic reforming unit of Tabriz oil refining company was investigated in this article. This unit uses four radial reactors in series, and the Smith’s model was used for its reaction kinetics. Several models were considered for activity of catalysts to determine the major reason of catalyst deactivation. Presented models have parameters, as the objective function is optimized these parameters are obtained. In definition of the objective function the outlet temperature of reactors and outlet composition of fourth reactor should have high overlapping with experimental values. Optimization shows that deposition of coke and slightly high temperature cause the deactivation of catalysts in catalytic reforming of naphtha.
