Key factors influencing the release and formation of HCN during pyrolysis of iron-containing coal

Minerals inherently present in coal and iron-containing compounds externally added have an important influence on the formation and release of HCN-one of the main precursors of NOx during coal pyrolysis. Pyrolysis of raw coal and demineralized coal with different ranks and iron-containing compounds was studied in a fixed bed quartz reactor at temperature programmed in this article. The trend and influencing factors of HCN formation and release during coal pyrolysis were examined. The results showed that the effect of iron-containing compounds in coal on HCN release depended on the coal types, and the iron added by impregnation and precipitation methods played different roles on HCN formation for different coal types. Additionally, the effects of the particle size and the reaction time on HCN formation during pyrolysis of coal with iron were also studied.