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Kinetic, experimental, modeling, and simulation studies of a catalytic high temperature (673−873 K) water−gas shift reaction (WGSR) were performed in a packed bed tubular reactor (PBTR) at several values of W/F A0 (ratio of the mass of the catalyst to the mass flow rate of CO, g(cat)·h/mol of CO) over a new Ni−Cu/CeO2−ZrO2 (UFR-C) catalyst. Out of the kinetic models evaluated, the one that best predicted the experimental rates was based on the Langmuir−Hinshelwood (LH) formulation, assuming that the rate determining step (RDS) was the surface reaction between molecularly adsorbed carbon monoxide and water to give a formate intermediate and atomically adsorbed hydrogen. Reactor modeling was performed using a comprehensive numerical model consisting of two-dimensional coupled material and energy balance equations. The best mechanistic kinetic model developed was incorporated in the reactor model, which also contained the axial dispersion term, and was solved using the finite elements method. The validity of the reactor model was tested against the experimental data and a satisfactory agreement between the model prediction and measured results were obtained. In addition, the predicted concentration and temperature profiles for our process in both axial and radial direction indicate that the assumption of plug flow isothermal behavior is justified within certain kinetic operating conditions. Moreover, the well-known criteria for neglecting the axial dispersion term have been met in this case and it can conclusively be recommended to be eliminated from the model.