杂质对过硫酸铵热稳定性的影响

The Influence of Impurities on Thermal Stability of Ammonium Sulfate

为研究常见杂质如水、酸碱、金属、盐及橡胶等物质对过硫酸铵热稳定性的影响,对过硫酸铵及过硫酸铵与不同杂质混合物在空气中的热分解反应和放热特性进行了测试,得到反应热、起始放热温度等热稳定性参数,在此基础上研究其反应动力学,得到表观反应活化能、指前因子等动力学参数,利用Semenov热爆炸模型计算了过硫酸铵及过硫酸铵与不同杂质混合物的自加速分解温度(SADT)。结果表明:杂质的加入使过硫酸铵的热稳定性降低,计算得到过硫酸铵的SADT为155℃,通过对过硫酸铵及过硫酸铵与不同杂质混合物的SADT进行比较,发现上述杂质的加入均能使过硫酸铵的SADT降低,其中水、酸、氢氧化钠加入后过硫酸铵的SADT分别降低至75℃、80℃和75℃。

Thermal decomposition reaction between ammonium sulfate and persulfate with different impurity mixtures in air and their exothermie characteristies were tested so as to study the influences of common impurities such as water, acid-base, metal, sah, rub and other substances on the thermal stability of ammonium sulfate. Consequently, the thermal stability parameters including reaetion heat and heat release temperature at the beginning were obtained, based on which their reaction dynamics were studied with the consequence that the apparent reaetion activation energy, pre-exponential factor and other dynamic parameters were obtained. In addition, the SADT of ammnnium sulfate and persulfate with different impurity mixtures were calculated through Semenov heal explosion model. The result showed that the addition of impurity brought about the reduction in thermal sta- bility of ammonium sulfate. SADT of ammonium persulfate was 155℃ as calculated. Through comparison of SADT of ammonium sulfate and persulfate and different impurity mixtures, it＇ s found thai the addition of the ahovementioned impurities coould bring about reduction in SADT of ammonium sulfate, for SADT of ammonium persulfate, it＇s reduced to 75℃ , 800℃ and 75℃ after the addition of water, acid and sodium hydroxide.