The Influence of Li_2O doping (0.75-3.0 mol percent) on surface and catalytic properties of NiO/Fe_2O_3, having a molar ratio of 1:2, was investigated. Pure and doped mixed solids were heated in air at 700 and 800 deg C. The surface characteristics of various solids were determined from N_2-adsorption isotherms conducted at - 196 deg C and their catalytic activities were measured by following up the kinetics of CO oxidation by O_2 at 300-400 deg C using a static method. The results revealed that the doping process brought about an increase in the specific surface area (S_(BET)) of mixed solids. A maximum increase of about two-fold was observed by treating with 1.5 percent Li_2O. On the other hand, this treatment resulted in a drastic decrease (about 50 percent) in the catalytic activities of the doped catalysts. Lithium oxide doping altered the pre-exponential factor of the Arrhenius equation without changing the magnitude of the apparent activation energy of the catalytic reaction which might indicate that Li_2O did not change the mechanism of the catalytic reaction.
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