摘要
为了探究二氧化硅气凝胶的热解动力学和反应机理,采用无模式函数法通过热重数据获得了二氧化硅气凝胶的活化能,发现二氧化硅气凝胶在氮气中的热解过程较为复杂。通过分峰分析,将反应速率曲线分为6个子反应并得到了每个子反应的活化能,同时采用Coats-Redfern法确定每个子反应的反应机理。结果表明:在氮气条件下的6个子反应符合两类机理,即假定随机成核及其随后的生长和化学反应;整个热解过程的平均活化能和指前因子的自然对数分别为375.97 kJ/mol和60.89 min^(-1)。
In order to investigate the pyrolysis kinetics and reaction mechanism of silica aerogel,the activation energies of silica aerogels were obtained from thermogravimetric data using the model-free methods,from which it can be concluded that the pyrolysis process in nitrogen is complex.Peak-differentiating analysis was used to divide the reaction rate curves into six sub-reactions and obtain the activation energy of each sub-reaction.Coats-Redfern method was used to determine the reaction mechanism of each sub-reaction.The results showed that the six sub-reactions in nitrogen conform to two types of mechanisms,i.e.,the assumed random nucleation and its subsequent growth and chemical reactions.The average activation energy and the natural logarithm of the pre-exponential factor for the whole pyrolysis were 375.97 kJ/mol and 60.89 min^(-1),respectively.
作者
马院生
阮驰驰
陈冠宇
刘鑫羽
何松
李治
杨小兵
MA Yuansheng;RUAN Chichi;CHEN Guanyu;LIU Xinyu;HE Song;LI Zhi;YANG Xiaobing
出处
《武汉理工大学学报（信息与管理工程版）》
2023年第2期206-211,共6页
Journal of Wuhan University of Technology：Information & Management Engineering
基金
国家自然科学基金项目(52074201,51706165)。
关键词
气凝胶
热解
分峰分析
动力学
反应机理
aerogels
pyrolysis
peak-differentiating analysis
kinetics
reaction mechanism
