pH值对双氧水绝热分解特性的影响

为了考察pH值对双氧水热危害的影响,利用VSP2绝热量热仪对pH值分别为1.8,4,5,6,7及8的质量分数为27.5%的双氧水进行了绝热条件下测试,得到了不同pH值双氧水的绝热分解特征,求得了双氧水的分解动力学,并计算得到双氧水在起始温度为30℃时绝热条件下到达最大反应速率所需时间。结果表明:当双氧水pH值增加时,起始放热温度降低,到达最大反应速率所需时间缩短,热失控危险性明显增加,双氧水在工业条件下存储时,当pH值增加至6时就有一定危险性,当pH值增加至7以上时热失控几乎不可避免。

Effect of pH value on adiabatic decomposition characteristics of hydrogen peroxide

In order to study the influence of pH value on the thermal hazard of hydrogen peroxide,VSP2(Vent Size Package 2) was used to analyze the thermal behavior of hydrogen peroxide(mass fraction 27.5%) with different pH values of 1.8,4,5,6,7,8 under adiabatic condition.The adiabatic decomposition characteristics of the hydrogen peroxide with different pH values were recorded.The thermal decomposition kinetics of the decomposition reaction concerned was obtained.The time to the maximum reaction rate at 30 ℃ under adiabatic condition was also worked out from the kinetics data.The results show that as the pH value of hydrogen peroxide increasing,the onset exothermic temperature decreases,and the time to the maximum reaction rate under adiabatic conditions gets shorter,so the risk probability of thermal runaway significantly increases.When hydrogen peroxide is stored in the industrial conditions,there is a certain risk when pH value is 6,and thermal runaway is almost inevitable when pH value is more than 7.