煤低温氧化过程中元素转化行为的动力学分析

通过把参与氧化反应的复杂的煤有机体，分成C，H，O，S和N元素，并基于氧化过程中这些元素含量的变化，借助于准一级反应模型，Coats and Redfern’s模型和Freeman and Carroll’s模型，对煤低温氧化动力学特性进行研究。研究表明，这些元素转化遵循准一级反应动力学和Coats and Redfern’s模型，并且这两种模型计算得到的活化能比较接近。在煤低温氧化过程中这些元素表现出较低的反应速率，仅为10-5～10-6，这表明中间络合物的生成速率非常缓慢。同时研究证明了不同元素活化能与指前因子之间存在动力学补偿效应。

Kinetic analysis of element evolution during low-temperature oxidation of coal

The complex macromolecular matrix of coal was divided into the elements of C，O，H，S and N，which were involved in the oxidation reaction.Based on the changes of element contents during coal oxidation process at low temperature，the three kinetic models，including pseudo-first-order kinetics model，Coats and Redfern’s model，and Freeman and Carroll’s model，were introduced to investigate the kinetic characteristics of coal oxidation at low temperature.Kinetic study reveals that the evolutions of these elements during coal oxidation at low temperature follow pseudo-first order kinetics and Coats and Redfern’s model.The activation energies for these elements evolution in the oxidation process by using the pseudo-first order kinetics have been found to be almost similar to those calculated by applying the Coats and Redfern’s equation.The reaction rates computed by the pseudo-first order kinetics are very low and have been found to be 10-5-10-6，suggesting a very low rate of successful collisions for the formation of activated complex.A kinetic compensation effect between the activation energy and exponential facto was also observed for the evolutions of these elements.