摘要
对CO2气氛下CaCO3的热分解过程进行了研究.采用Flynn-Wall-Ozawa公式,避开反应机理函数,求得不同转化率α下的表观活化能E,并将其外推至零,得到新物相晶核形成时的活化能Eα→0=1921.88 kJ/mol.然后运用Coats-Redfern积分式,计算出对应于30种机理函数和不同升温速率β下的表观活化能E,并将升温速率β外推至零,得到样品在热平衡态下的Eβ→0,比较Eα→0和Eβ→0后,可认为此反应过程最概然机理函数,即为n=1/4的成核与生长过程.分析了CO2气氛下CaCO3热分解经历的几个过程.
The decomposition kinetics of CaCO3 in CO2 atmosphere was researched. The activation energy under different conversion fraction a is obtained using Flynn-Wall-Ozawa method. The derived value Eα→0, that is the conversion 'fraction α is extrapolated to zero, is 1921.88 kJ/mol. Then, Coats- Redfern integral equation is used to calculate activation energy E corresponding different heating rate β and 30 different kinetic functions. The activation energy Eβ→0, which the heating rate β is extrapolated to zero, is obtained. Comparing Eα→0 with Eβ→0, the decomposition mechanism of CaCO3 in CO2 is concluded to be nuclear producing and growing process (n= 1/4) and several processes on the decomposition of CaCO3 in CO2 are analyzed.
出处
《华中科技大学学报(自然科学版)》
EI
CAS
CSCD
北大核心
2007年第8期87-89,共3页
Journal of Huazhong University of Science and Technology(Natural Science Edition)
基金
国家重点基础研究发展计划资助项目(2006CB70580702)
国家自然科学基金资助项目(50376016)
关键词
CO2捕捉
CACO3
反应动力学
双外推法
反应机理
CO2 capture
CaCO3
chemical kinetics
double extrapolated method
decomposition mechanism