Pyridine is one of the main nitrogen-containing compounds in coal,and its pyrolytic mechanism to generate NO_(x)precursors(mainly NH_(3)and HCN)remains unclear.In this work,the possible pathways for the pyrolysis of p...Pyridine is one of the main nitrogen-containing compounds in coal,and its pyrolytic mechanism to generate NO_(x)precursors(mainly NH_(3)and HCN)remains unclear.In this work,the possible pathways for the pyrolysis of pyridine to form HCN and/or NH_(3)were investigated by the density functional theory method,and the effects of H_(2)O 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 NH_(3).The existence of H_(2)O has significant effects on the decomposition of pyridine,as it participates in pyridine pyrolysis to form NH_(3)rather than HCN as the major product.展开更多
基金the National Natural Science Foundation of China(Grant Nos.51922040 and 51821004)China Postdoctoral Science Foundation(Grant No.2019TQ0091)+1 种基金Grants from Fok Ying Tung Education Foundation(Grant No.161051)Fundamental Research Funds for the Central Universities(Grant Nos.2020DF01,2020 MS020,2018ZD08)for financial support.
文摘Pyridine is one of the main nitrogen-containing compounds in coal,and its pyrolytic mechanism to generate NO_(x)precursors(mainly NH_(3)and HCN)remains unclear.In this work,the possible pathways for the pyrolysis of pyridine to form HCN and/or NH_(3)were investigated by the density functional theory method,and the effects of H_(2)O 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 NH_(3).The existence of H_(2)O has significant effects on the decomposition of pyridine,as it participates in pyridine pyrolysis to form NH_(3)rather than HCN as the major product.
