Experimental Method on Rapid Identification of Autocatalysis in Decomposition Reactions

Many chemical substances will decompose in an autocatalytic manner, and such autocatalytic behavior can be identified through isothermal measurements, such as using differential scanning calorimetry(DSC) and microcalorimetry(C80). However, since it is difficult to predict the appropriate temperature for isothermal testing, it would be helpful to develop a simple and effective experimental method to distinguish autocatalytic decomposition. Based on the results of Roduit et al., a new technique for identifying autocatalysis is described herein, termed theinterruption and re-scanningmethod. The decompositions of 2-ethylhexyl nitrate(EHN), 2,4-dinitrotoluene(2,4-DNT), dicumyl peroxide(DCP), and cumyl hydroperoxide(CHP) were assessed using both this new method and isothermal approach. Based on the results, the decompositions of EHN and DCP were found to proceed accord to thenth orderlaw,whereas 2,4-DNT and CHP decomposed autocatalytically. We conclude that the interruption and rescanning method can be used to identify the characteristics of autocatalysis both quickly and effectively.