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NO_x is one of the major air pollutants. In recent years, although China has performed a more stringent emission standards, NO_x emissions are not reduced even in some areas it has a slight increase, How to effectively reduce NO_x, has become more and more important.In this paper, activated carbon (AC) and activated carbon fiber(ACF) were pretreated by 50% nitric acid, and then the oxides of Fe, Co, Ni, Cu and the composite oxides with lanthanum were loaded. The research is about the catalytic ability to remove NO_x.In this paper,impregnation method was used to make catalyzer. The result shows that when catalyzer was loaded on AC or ACF the ability to remove NO_x can be enhanced. For single-metal oxide system, the catalytic performance in aerobic conditions is higher than in anaerobic conditions. The catalyzer shows great efficiency in the temperature range of 200℃～350℃, But at a higher temperature range the catalytic effect was decrease.The different oxygen content can cause the formation of different species, so the surface adsorption-desorption affecting will be changed, and the overall performance of catalytic performance will different. In general, at our experiment,3% and 6% oxygen content shows great catalytic properties.The catalytic efficiency of La oxide loaded on AC and ACF is lower than Fe, Co, Ni, Cu oxide loaded. The efficiency to remove the NO will be increased with the content of La loading when content is no more than 5%. When La oxide was composited with metal oxide, the reaction stability of the catalytic can be increased. The composite oxides can effective remove NO at 300℃with the content 6% oxygen conditions, and 5% content of La oxide was contained in this composite, the remove efficiency is more than 90%, and it also shows great catalysis efficiency at the temperature range of 300℃～400℃.In this paper, the possible chemical reaction process has been discussed via the changes about NO_x and COx.
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