玉米秸秆颗粒热解活化过程的热力学和动力学研究

Research on Thermodynamics and Kinetics of Pyrolysis and Activation Processes of Corn Stalk Pellet

利用热重分析研究了玉米秸秆颗粒制备活性炭的热解和活化过程。热解采用氮气为保护气体，升温速率5K／min，终温723K，恒温时间30min。热解过程主要发生在450-620K之间，热解炭材微孔结构和机械强度良好。活化采用CO：为活化剂，升温速率10K／min，终温1073K，恒温时间20min，活化反应主要发生在950-1070K之间，得到的活性炭具有较大的比表面积（404．6m^2／g）和优良的吸附性能。通过对热解和活化过程的热重及差热变化综合分析，确定了两段热化学反应的活化能和频率因子，了解了热解和活化过程的热力学和动力学特性，为制备优质的生物质颗粒活性炭提供理论指导作用。

The processes of pyrolysis and activation of corn stalk pellets for the activated carbon production were studied by thermogravimetry. The pyrolysis conditions were： nitrogen as shield gas, temperature rate 5 K/min, final temperature 723 K and thermostatic time 30 min. The process of pyrolysis oecured primarily between 450 -620 K, the mierocellular structure and mechanical strength of pyrolysis char were good. The activation conditions were ： carbon dioxide as shield gas, temperature rate 10 K/min, final temperature 1 073 K and thermostatic time 20 min. The process of activation oeeured primarily between 950-1 070 K, the obtained activated carbon has high specific surface（404.6 m2/g） and excellent adsorption abilities. The acti- vation energy and frequency factor parameters were determined by analysis of the thermogravimetric and differential thermal characteristics of the pyrolysis and activation processes. The thermodynamic and kinetic characteristics of pyrolysis and activation processes were concluded. It will provide theoretical guide to the production of better biomass activated carbon pellets.