More stringent regulations for NO{sub}x control in pulverized coal combustors have made the scientific community focus on sources of emissions that were traditionally considered less relevant to the overall NO{sub}x production. The oxidation to NO of the nitrogen that is organically bound to the char is one of them. In this study, an experimental evaluation of the influence of the reduction of NO by char was carried out. The experiments with three different carbonaceous materials were conducted at temperatures close to that of pulverized combustion conditions (1700 K) in a laminar drop tube reactor and under inert and oxidizing atmospheres. The results obtained show that the process of NO reduction on the char plays an important role on the total amount of char-N converted to NO{sub}x. This NO destruction pathway becomes less important at low NO background concentration and doesn't seem to strongly dependant on the char nature. The predictions of a single particle model were compared to the experimental results. Although the model predicts a reduction on the conversion of char-N to NO that increases in proportion to NO concentration, it overpredicts the general value. A higher value for the rate of NO destruction on char surface doesn't seem to explain this phenomena that seems to be more related to the availability of char surface for the destruction of NO.
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