74 石炭中に元々存在する金属イオンと熱分解時における窒素化合物分布の関係(コークス強度,熱分解)

抄録

Effects of metal cations inherently-present in coals on the fate of coal-N in the fixed bed pyrolysis at 1000℃ have been studied with a quartz reactor using 25 coals with 62-81 wt% (daf) C. Among N_2, NH_3, HCN and tar-N evolved, N_2 is the predominant product for almost all of the coals, and there is a reverse relationship between N_2 and char-N, which means that N_2 originates predominantly from char-N. When 8 kinds of metal elements are determined and correlated with N_2 yield, a strong correlation between N_2 formation and inherent Fe content exists for low rank coals with less than 75 wt% C. The catalysis of conversion reactions of char-N to N_2 by nanoscale particles of metallic Fe, which is formed from naturally-present Fe ions, is discussed in terms of strong interactions between Fe nanoparticles and heterocyclic nitrogen structures in the char matrix.