Pyridine is one of the main nitrogen-containing compounds in coal, and its pyrolytic mechanism to generate NO_x precursors (mainly NH₃ and HCN) remains unclear. In this work, the possible pathways for the pyrolysis of pyridine to form HCN and/or NH₃ were investigated by the density functional theory method, and the effects of H2O on pyridine pyrolysis were also investigated. The results show that there are two possible reactions for the initial pyridine pyrolysis, i.e., internal hydrogen transfer and C-H bond homolysis, and that internal hydrogen transfer is more favorable. Nine possible reaction pathways following internal hydrogen transfer are obtained and analyzed. Among these pathways, pyridine prefers to produce HCN instead of NH₃. The existence of H₂O has significant effects on the decomposition of pyridine, as it participates in pyridine pyrolysis to form NH₃ rather than HCN as the major product.

吡啶是在煤的主要含氮化合物中的一种，其热解机制来生成NO _X的前体（主要是NH ₃和HCN）仍不清楚。在这项工作中，通过密度泛函理论方法研究了吡啶热解生成HCN和/或NH ₃的可能途径，并研究了水对吡啶热解的影响。结果表明，初始吡啶热解有两种可能的反应，即内部氢转移和CH键均解，并且内部氢转移更有利。获得并分析了内部氢转移后的九种可能的反应途径。在这些途径中，吡啶更倾向于生成HCN而不是NH ₃。H ₂ O的存在对吡啶的分解有重要影响，因为它参与吡啶热解形成NH ₃而不是主要产物HCN。