两种量热模式下物质热分解的动力学补偿效应

发布时间：2018-06-16 13:12

本文选题：动力学补偿效应 + 绝热模式　；参考：《物理化学学报》2016年02期

【摘要】：热分析量热仪主要包括动态、等温、恒温及绝热四种操作模式。很多学者基于动态及等温模式的测试结果,采用Arrhenius速率常数进行动力学计算,进而发现了所谓的"动力学补偿效应"。为了解绝热模式下是否也存在动力学补偿效应,分别采用绝热加速量热法(ARC)及动态差示扫描量热法(DSC)研究了过氧化二异丙苯(DCP)、40%(质量分数,下同)DCP溶液、葡萄糖、45%葡萄糖溶液的热分解特性,在此基础上基于Arrhenius公式计算了对应的表观活化能E和指前因子A,并对计算结果进行了分析。结果表明:绝热模式下,不同质量的同种样品及其溶液的最佳动力学参数,或者同一组数据采用不同的反应级数获得的lnA和E之间均存在明显的线性关系。此外,尽管由动态DSC数据计算获得的E和lnA普遍小于绝热模式的结果,但两种模式下获得的lnA和E之间仍然存在动力学补偿效应。由此可以推断,具有相同或类似反应机理的反应,虽然实验模式不同,但其E和lnA之间存在明显的动力学补偿效应。
[Abstract]:Thermal analysis calorimeter mainly includes four operation modes: dynamic, isothermal, isothermal and adiabatic. Based on the test results of dynamic and isothermal models, many scholars use the Arrhenius rate constant to calculate the kinetics, and then find the so-called "dynamic compensation effect". In order to find out whether there is dynamic compensation effect in adiabatic mode, the dynamic differential scanning calorimetry (DSCC) and adiabatic accelerated calorimetry (ARC) were used to study the dicumyl peroxide (DCPP) solution. On the basis of the thermal decomposition characteristics of 45% glucose solution, the corresponding apparent activation energy E and preexponential factor A were calculated based on the Arrhenius formula, and the calculated results were analyzed. The results show that under adiabatic mode, the optimal kinetic parameters of the same sample and its solution of different mass, or the linear relationship between lnA and E obtained by different reaction order of the same group of data are obvious. In addition, although the results of E and lnA calculated by dynamic DSC data are generally smaller than those obtained by adiabatic mode, there is still a dynamic compensation effect between the lnA and E obtained by the two modes. It can be inferred that the reaction with the same or similar reaction mechanism has obvious kinetic compensation effect between E and lnA, although the experimental model is different.
【作者单位】：南京理工大学化工学院安全工程系;常州出入境检验检疫局;
【基金】：国家自然科学基金(51204099) 江苏出入境检验检疫局科技计划(2014KJ59)资助项目~~
【分类号】：O643.1

【相似文献】