Acta Phys. -Chim. Sin. ›› 2016, Vol. 32 ›› Issue (2): 391-398.doi: 10.3866/PKU.WHXB201511023

• COMMUNICATION • Previous Articles     Next Articles

Kinetic Compensation Effect under Two Different Calorimetric Modes for Thermal Decomposition

Rui-Li YIN1,Li-Ping CHEN1,Wang-Hua CHEN1,Ke WU2,Cai-Xing ZHANG1,Han LI1,Cheng YU1   

  1. 1 Department of Safety Engineering, School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China
    2 Changzhou Entry-Exit Inspection and Quarantine Bureau, Changzhou 213003, Jiangsu Province, P. R. China
  • Received:2015-10-06 Published:2016-01-30
  • Supported by:
    the National Natural Science Foundation of China(51204099);Science and Technology Plan Projects of JiangsuEntry-Exit Inspection and Quarantine Bureau, China(2014KJ59)

Abstract:

Thermal analysis calorimeters can be used with different temperature control modes. Dynamic, isothermal, isoperibolic, and adiabatic modes are commonly used. A kinetic compensation effect was discovered when the kinetic parameters were calculated using the Arrhenius equation, based on dynamic and isothermal data. To determine whether the kinetic compensation effect existed in adiabatic mode, accelerating rate calorimetry (ARC) and differential scanning calorimetry (DSC) were used to obtain thermal decomposition curves of dicumyl peroxide (DCP), 40%(w) DCP in ethylbenzene, glucose, and 45% (w) glucose in water. The apparent activation energies (E) and pre-exponential factors (A) were calculated based on the Arrhenius rate constant. An obvious kinetic compensation effect was observed in a plot of lnA vs E for a given sample at different concentrations or for the same set of ARC data analyzed with different reaction orders n. Although the calculated lnA and E values using the dynamic differential scanning calorimetry data were usually lower than those using the adiabatic ARC data, a significant kinetic compensation effect existed between the two sets of results. This result suggested that the kinetic compensation effect existed between the activation energy and pre-exponential factor in reactions with the same or similar reaction mechanisms, regardless of the temperature control mode.

Key words: Kinetic compensation effect, Adiabatic model, Dynamic model, Activation energy, Pre-exponential factor

MSC2000: 

  • O643