流化床燃烧温度下N_2O与石油焦焦炭多相反应动力学的热重研究

Thermogravimetric studies on the heterogeneous reaction kinetics of petroleum coke char with nitrous oxide under temperature range of fluidized bed

采用升温热重方法研究了流化床温度条件下N2O与石油焦焦炭的多相反应动力学特性，实验中设置升温范围为973～1273K，升温速率为5K·min^-1,估算及灰色关联分析的结果表明，在流化床工况下，N2O与石油焦焦炭间的多相反应由内扩散过程控制，尤其是气体在石油焦焦炭中孔中的扩散对于多相反应的进行具有重要作用．同时，采用Coats—Redfem法对升温热重数据进行了分析，得到了4种不同石油焦焦炭（JMchar、ZH char、WHchar和GH char）的动力学机理及动力学参数，JMchar、ZHchar、WHchar和GHchar的活化能分别为128．9、113．8、154．1和127．3kJ·mol^-1．

The global kinetics of the heterogeneous reaction between N2O and petroleum coke char in the combustion temperature range of fluidized bed were studied using a programmed-temperature thermogravimetric system. The temperature range was from 973K to 1273K, and the heating rate was 5 K. min^-1. The results of estimation and grey relation analysis indicated that the heterogeneous reaction of N2O with petroleum coke char was governed by the internal diffusion in the pore of petroleum coke char, especially in mesopore in metioned temperature range. The kinetic mechanism and kinetic parameters of four types of petroleum coke chars were determined using Coats-Redfern method. The heterogeneous reaction mechanism of GH char,ZH char and WH char can be described by - In（ 1 - X）, and the reaction mechanism function of JM char is [ In （ 1 - X） ] 1/2. The activation energy of JM char,ZH char,WH char and GH char are 128.9,113.8,154.1 and 127.3 kJ. mol^-1, respectively.