东北大学学报:自然科学版 ›› 2018, Vol. 39 ›› Issue (3): 398-403.DOI: 10.12068/j.issn.1005-3026.2018.03.019

• 资源与土木工程 • 上一篇    下一篇

微细菱镁矿热分解过程及动力学

白丽梅1,2, 邓玉芬2, 韩跃新1, 赵文青2   

  1. (1. 东北大学 资源与土木工程学院, 辽宁 沈阳110819; 2. 华北理工大学 矿业工程学院, 河北 唐山063009)
  • 收稿日期:2016-10-09 修回日期:2016-10-09 出版日期:2018-03-15 发布日期:2018-03-09
  • 通讯作者: 白丽梅
  • 作者简介:冯明杰(1971-), 男, 河南禹州人, 东北大学副教授; 王恩刚(1962-), 男, 辽宁沈阳人, 东北大学教授,博士生导师.白丽梅(1979-),女,河北邯郸人,东北大学博士研究生,华北理工大学副教授; 韩跃新(1961-),男,内蒙古赤峰人,东北大学教授,博士生导师.
  • 基金资助:
    国家自然科学基金资助项目(51171041).国家自然科学基金资助项目(51504078); 河北省自然科学基金资助项目(E2015209210).

Thermal Decomposition Process and Kinetics of Micro-fine Magnesite

BAI Li-mei1,2, DENG Yu-fen2, HAN Yue-xin1, ZHAO Wen-qing2   

  1. 1. School of Resources & Civil Engineering, Northeastern University, Shenyang 110819, China; 2. School of Mining Engineering, North China University of Science and Technology, Tangshan 063009, China.
  • Received:2016-10-09 Revised:2016-10-09 Online:2018-03-15 Published:2018-03-09
  • Contact: HAN Yue-xin
  • About author:-
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摘要: 采用TG-DSC热分析技术,在不同升温速率下对高纯微细菱镁矿进行热分解动力学研究.结果表明:随着升温速率的增大,菱镁矿分解速率不断增大且最大分解速率也向高温区偏移.首先使用Hu-Gao-Zhang方程对不同升温速率的TG数据进行计算,确定了热分解机理函数的唯一性和活化能.进而采用双等双步法和产品形貌分析,确定其最概然机理函数为f(α)=2(1-α)1/2,热分解沿解理面向内进行,属于典型的相边界反应.最后利用Flynn-Wall-Ozawa方程求得指前因子,建立了微细菱镁矿的热分解动力学方程.用两组不同升温速率的TG数据对所建立方程进行验证,方程合理.

关键词: 菱镁矿, 热分解, 动力学, 分解机理, 热重分析

Abstract: Thermal decomposition kinetics of highly pure micro-fine magnesite particles was studied by TG-DSC techniques at varying heating rates. The results indicate that with increase of heating rate, decomposition rate of magnesite increases gradually and maximum decomposition rate shifts to the high-temperature zone. Firstly, TG experimental data obtained at different heating rates were calculated with Hu-Gao-Zhang equation, which determined uniqueness and activation energy value of thermal decomposition mechanism function of magnesite. And then double equal-double steps method combined with morphological analysis on calcined products were adopt to determine differential form for most probable mechanism function of thermal decomposition, it is f(α)=2(1-α)1/2, and the outside-in (i.e. from cleavage surfaces to the interior of crystal) thermal decomposition of particles is a typical phase boundary reaction. Finally the pre-exponential factor was calculated by Flynn-Wall-Ozawa equation, and thermal decomposition kinetics equation of micro-fine magnesite is established. Two sets of TG data with different heating rates were used to verify the established equation and prove it is reasonable equation.

Key words: magnesite, thermal decomposition, kinetics, decomposition mechanism, thermogravimetric analysis

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