乙酰氧肟酸的热稳定性分析

Thermal Stability Analysis of Acetohydroxamic Acid

为预防化工生产、储运和使用中由乙酰氧肟酸(Acetohydroxamic acid,AHA)引发的火灾和爆炸事故,采用绝热量热法对其热稳定性进行实验研究,并将加速量热仪(Accelerating Rate Calorimeter,ARC)的测试结果与差示扫描量热仪(Differential Scanning Calorimetry,DSC)的结果进行了比较.ARC绝热测试结果表明,AHA的初始放热温度为352.68K,最高放热温度为465.82K,最大温升速率和最大温升速率时间分别为8.748K·min-1和382.65min,单位质量AHA生成气体的最大压力为2.22MPa·g-1.根据ARC绝热测试结果,采用速率常数法计算了AHA的动力学参数表观活化能和指前因子,并求出了AHA的某种典型包装的不可逆温度和自加速反应温度.研究结果表明,AHA的热稳定性较差,爆炸性较强。

To prevent fire and explosion accident caused by acetohydroxamic acid （AHA）, the adiabatic stability of AHA was investigated by an accelerating rate calorimeter （ARC） in this paper. Comparison of test results from ARC and differential scanning calorimetry （DSC） was carried out. The test results show that the initial exothermic temperature for AHA was 352.68 K, the maximum exothermic temperature was 465.82 K, maximum self-heating rate and the time to maximum self-heating rate were 8.748 Komin 1 and 382.65 min respectively, and the maximum pressure produced by unit mass was 2.22 MPaog l. The high thermal hazard and powerful explosion of AHA were demonstrated by the results of DSC and ARC. Finally, The kinetic parameters such as apparent activation energy and pre-exponential factor of the thermal decomposition of AHA were calculated by a rate constant method, and the temperature of no return （TNR） and self accelerating reaction temperature （TsART） of AHA with some specific package were predicted. The studies have revealed that AHA is sensitive to thermal effect, and the thermal decomposition is hazardous due to its serious pressure effect.