碱金属离子对吡咯热解生成 NOx前驱物 HCN 机理的影响.

Pyrrole is selected as the N-containing model compound for the investigation of the effect of alkali metal ions(Na+,K+) on NOxformation during coal thermal utilization process.Based on conventional non-catalytic mechanism studies, the density functional theory(DFT) method and B3 LYP/6-31+G(d,p) basis set are adopted to elucidate the pyrolysis mechanism and pathways of pyrrole. The calculation results indicate that both Na+ and K+ show significant effects on the internal hydrogen transfer,ring-opening and concerted decomposition reactions, while rarely influence the internal hydrogen isomerization reaction. It is found that the alkali metal ions(Na+ and K+) can promote the formation of HCN from pyrrole through decreasing the activation energy of the rate-determining step. In addition,Na+exhibits a better catalytic activity than K+. [ABSTRACT FROM AUTHOR]