The paper describes a model for deep catalytic oxidation of hydrocarbon mixtures in the strong pore diffusion region. A laboratory-scale tubular catalytic reactor, used for low-temperature (160-360 C) deep catalytic oxidation of n-hexane and benzene as single components and in a binary mixture, was modeled both with and without internal (pore) diffusion effects. Experimental conversion data for a 0.1% Pt, 3% Ni/gamma-A12O3 catalyst, using 120 x 170 mesh particles, were compared to model predictions. Both models provided similar predictions of the single component results indicating the absence of pore diffusion effects in the 120 x 170 mesh particles. Benzene oxidation in the binary mixture was somewhat overpredicted throughout the temperature range, indicating the need for a more rigorous kinetic mechanism. Single component n-hexane oxidation was overpredicted above 260 C, presumably due to external diffusion effects in the laboratory reactor.