【摘要】 针对煤中常见含铁矿物黄铁矿在富氧燃烧典型气氛下转化特性，通过同步热分析结合烟气分析研究了黄铁矿在CO₂气氛下的转化行为．结果发现，黄铁矿在CO₂气氛下主要经历5个失重阶段且均为吸热过程，首先是黄铁矿颗粒表面硫脱除的起始热解段（相界面反应，n=1/2），活化能低于其在N₂气氛下近30 k J/mol，为220.27 k J/mol，随后裂解成磁黄铁矿（三维扩散，n=1/2）活化能与其在N₂（177.27 k J/mol）下接近为178.1 k J/mol；温度高于690℃，随着升温磁黄铁矿缓慢失硫，CO₂逐渐参与磁黄铁矿转化且释放SO₂和CO;820～1 150℃经历双峰失重峰阶段，820～1 020℃，氧化气体产物SO₂大量生成且在约1 000℃达到体积浓度峰值；最后1 020～1 150℃，坩埚中残留物大量与CO₂持续氧化反应失重形成SO₂和CO，坩埚中形成复杂物相体系，铁硫化物和铁氧化物共存（或共融）．CO₂参与黄铁矿产物转化失重阶段活化能分别为180.94 k J/mol、229.69 k J/mol和243.46 k J/mol，动力学机制均为成核与生长（n=1）.更多还原

【Abstract】 To investigate the transformation behavior of pyrite under typical oxy-fuel combustion atmosphere,the transformation behavior of pyrite in CO₂ atmosphere was studied by simultaneous thermal analysis and flue gas analysis.The results showed that the pyrolysis of pyrite can be mainly divided into five weight loss stages in CO₂atmosphere,all of which were endothermic processes.The activation energy of the initial pyrolysis stage （phase interface reaction,n=1/2） of sulfur removal on the surface of pyrite particles was 220.27 k J/mol in CO₂ atmosphere,which was about 30 k J/mol lower than that in N₂ atmosphere.Then,the pyrite was mainly decomposed into pyrrhotite （three-dimensional diffusion,n=1/2）,and the activation energy was 178.1 k J/mol （177.27 k J/mol in N₂）.When the temperature was raised above 690℃，the solid products continued to lose sulfur slowly,and CO₂ gradually participated in the conversion of solid products to release SO₂ and CO.At 820—1 150℃，the sample experienced bimodal weight loss peak stage.At 820—1 020℃，the oxidizing gas SO₂ was generated in large quantities and reached the maximum volume concentration at about 1 000℃.At the temperature between 1 020—1 150℃，a large amount of residue in the crucible continuously reacted with CO₂ to generate SO₂ and CO,and a complex phase system was formed in the crucible,in which iron sulfides and iron oxides co-existed （or formed eutectic mixtures）.The activation energies of the mass loss stages of pyrite decomposition products reacting with CO₂ are 180.94 k J/mol,229.69 k J/mol and 243.46 k J/mol,respectively,and the kinetic mechanisms are nucleation and growth （n=1）.更多还原