Mg(OH)_2 热分解反应的非等温动力学研究(英文)

The Non-isothermal Kinetic Analysis of Thermal Decomposition of Mg(OH)_2

用非等温动力学方法对氢氧化镁的热分解动力学进行了研究.分解反应机理符合晶核形成及生长机理A,且随着升温速率的升高,机理由A 2 转变为A 1.5.根据K issinger非机理方程计算和数值回归方法验证所得的分解反应活化能结果相互印证,约为148 kJ·m ol-1.进一步研究发现,水蒸气的存在对氢氧化镁热分解反应具有非常明显的影响,可能是其动力学机理随升温速率升高而改变的主要影响因素.

The thermal decomposition kinetics of magnesium hydroxide was investigated using the non-isothermal approach. It was proved that the mechanism of this reaction corresponded to the nucleation and growth mechanism A, but changed from A(2) to A(1.5) with rising heating rate. The activation energy of decomposition, both estimated by the non-mechanismic Kinssinger equation and calculated by a numerical regression method according to the deduced mechanism, was around 148 kJ center dot mol(-1). Further investigation revealed that water vapor had an extraordinarily significant effect on the thermal decomposition mechanism of magnesium hydroxide.