The reactions of organically-bound nitrogen in coal char during combustion have been studied in a laboratory furnace using size-graded char particles prepared by the pyrolysis of a Montana lignite. The time-resolved variations of nitrogen-to-carbon ratio during char oxidation have reveated that there is no selectivity between nitrogen and carbon loss due to oxidation but that the char-nitrogen can undergo devolatilization in parallel with the oxidation. The paper illustrates that the rates of devolatilization of fuel nitrogen can be obtained from oxidation experimentations under conditions where: (1) carbon devolatilization is unimportant, as in the case for char, and (2) the oxidation of nitrogen and carbon is nonselective. The oxidation rate of char-nitrogen can be given by the product of the char oxidation rate and the mole ratio of nitrogen to carbon in the char. The devolatilization rate of char-nitrogen is correlated by a first-order kinetics, showing good agreement with those of previous investigators.
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