分解反应自催化性质快速鉴别的实验方法

许多物质的分解都具有自催化特性,常用的自催化鉴别方法是利用差示扫描量热仪(DSC)、微量量热仪(C80)等进行等温实验判定(简称"等温法").但等温法的温度选择较为困难,因此很有必要从实验角度找到一种简便有效的自催化鉴定方法.本文基于Roduit理论模拟的结果,从实验角度提出了分解反应自催化特性的判定方法(简称"中断回扫法"),并利用该法以及等温法对4种样品(硝酸异辛酯(EHN)、2,4-二硝基甲苯(2,4-DNT)、过氧化二异丙苯(DCP)以及过氧化氢异丙苯(CHP))的分解特性进行判定.结果表明:EHN以及DCP的分解符合n级分解规律,而2,4-DNT以及CHP的分解符合自催化分解规律;中断回扫法可以快速、有效地用于鉴别物质分解是否具有自催化特性.

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 the“interruption and re-scanning”method. 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 the“nth order”law, 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.