Journal of Loss Prevention in the Process Industries ( IF 3.6 ) Pub Date : 2017-06-07 , DOI: 10.1016/j.jlp.2017.06.002
Chan-Cheng Chen , Horng-Jang Liaw , You-Nan Chen
Ionic liquids (ILs) are designated as green replacements to so far common used organic solvents because they are under the impression that ILs are both thermal stable and of very low volatility. However, recent studies have indicated that the fire and explosion hazard of ILs should be better understood beyond conventional hazard rating methods. In present work, the fire and explosion hazards of IL 1-Decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) ([C10mim][NTf2]) are investigated by the techniques of auto-ignition temperature tester, simultaneous application of thermogravimetry and differential scanning calorimetry (TGA/DSC), and the combination of thermogravimetric analysis with a Fourier transform infrared spectrometer (TGA-FTIR). The [C10mim][NTf2] exhibits a reverse thermal effect for DSC tests in different gas atmospheres: it exhibits endothermic effect in nitrogen atmosphere, but exhibits exothermic effect in air atmosphere. Part of the heat released in air atmosphere comes from the auto-ignition of heptane in the evolved gas in the DSC tests. The flash point of [C10mim][NTf2] is reported to be 140.2 °C in the literature, which is much lower than the onset temperature of [C10mim][NTf2] in nitrogen atmosphere. Therefore, the decomposition mechanisms of [C10mim][NTf2] in nitrogen atmosphere and in air atmosphere are distinct. The auto-ignition temperature of [C10mim][NTf2] is measured to be of 441°C by the method of ASTM E659-78 (2005a), but this temperature is much higher than the actual temperature at which it could be indeed ignited if sufficient time are allowable for the accumulation of heptane in the evolved gas.
中文翻译:

离子液体1-癸基-3-甲基咪唑鎓双(三氟甲基磺酰基)酰亚胺的可燃性
离子液体(IL)被指定为迄今为止常用有机溶剂的绿色替代品,因为它们的印象是IL既具有热稳定性,又具有极低的挥发性。但是,最近的研究表明,ILs的着火和爆炸危险应该超越常规危险等级方法。在目前的工作中,通过自动点火温度测试仪,热重分析仪的同时应用和差示法研究了IL 1-癸基-3-甲基咪唑双(三氟甲基磺酰基)酰亚胺([C10mim] [NTf2])的着火和爆炸危险扫描量热法(TGA / DSC),以及热重分析与傅里叶变换红外光谱仪(TGA-FTIR)的结合。[C10mim] [NTf2]在不同气体气氛下的DSC测试中表现出相反的热效应:它在氮气气氛中表现出吸热作用,但在空气气氛中表现出放热作用。空气中释放的部分热量来自DSC测试中所产生的气体中庚烷的自燃。据报道,[C10mim] [NTf2]的闪点为140.2°C,远低于[C10mim] [NTf2]在氮气气氛中的起始温度。因此,[C10mim] [NTf2]在氮气氛和空气气氛中的分解机理是不同的。[C10mim] [NTf2]的自燃温度通过ASTM E659-78(2005a)的方法测得为441°C,但该温度远高于实际温度,如果有足够的时间允许庚烷在放出的气体中积累。但在空气中表现出放热作用。空气中释放的部分热量来自DSC测试中所产生的气体中庚烷的自燃。据报道,[C10mim] [NTf2]的闪点为140.2°C,远低于[C10mim] [NTf2]在氮气气氛中的起始温度。因此,[C10mim] [NTf2]在氮气氛和空气气氛中的分解机理是不同的。[C10mim] [NTf2]的自燃温度通过ASTM E659-78(2005a)的方法测得为441°C,但该温度远高于实际温度,如果有足够的时间允许庚烷在放出的气体中积累。但在空气中表现出放热作用。空气中释放的部分热量来自DSC测试中所产生的气体中庚烷的自燃。据报道,[C10mim] [NTf2]的闪点为140.2°C,远低于[C10mim] [NTf2]在氮气气氛中的起始温度。因此,[C10mim] [NTf2]在氮气氛和空气气氛中的分解机理是不同的。[C10mim] [NTf2]的自燃温度通过ASTM E659-78(2005a)的方法测得为441°C,但该温度远高于在以下情况下可能被点燃的实际温度:有足够的时间允许庚烷在放出的气体中积累。空气中释放的部分热量来自DSC测试中所产生的气体中庚烷的自燃。[C10mim] [NTf2]的闪点据报道为140.2°C,远低于氮气氛中[C10mim] [NTf2]的起始温度。因此,[C10mim] [NTf2]在氮气氛和空气气氛中的分解机理是不同的。[C10mim] [NTf2]的自燃温度通过ASTM E659-78(2005a)的方法测得为441°C,但该温度远高于实际温度,如果有足够的时间允许庚烷在放出的气体中积累。空气中释放的部分热量来自DSC测试中所产生的气体中庚烷的自燃。据报道,[C10mim] [NTf2]的闪点为140.2°C,远低于[C10mim] [NTf2]在氮气气氛中的起始温度。因此,[C10mim] [NTf2]在氮气氛和空气气氛中的分解机理是不同的。[C10mim] [NTf2]的自燃温度通过ASTM E659-78(2005a)的方法测得为441°C,但该温度远高于在以下情况下可能被点燃的实际温度:有足够的时间允许庚烷在放出的气体中积累。该温度远低于氮气氛中[C10mim] [NTf2]的起始温度。因此,[C10mim] [NTf2]在氮气氛和空气气氛中的分解机理是不同的。[C10mim] [NTf2]的自燃温度通过ASTM E659-78(2005a)的方法测得为441°C,但该温度远高于实际温度,如果有足够的时间允许庚烷在放出的气体中积累。该温度远低于氮气氛中[C10mim] [NTf2]的起始温度。因此,[C10mim] [NTf2]在氮气氛和空气气氛中的分解机理是不同的。[C10mim] [NTf2]的自燃温度通过ASTM E659-78(2005a)的方法测得为441°C,但该温度远高于实际温度,如果有足够的时间允许庚烷在放出的气体中积累。