(1.昆明理工大學(xué)冶金系，昆明 650093;
2.昆明冶金高等專(zhuān)科學(xué)校， 昆明 650033)
摘 要: 將微波加熱用于從MnO2制備Mn3O4， 測(cè)定了MnO2和Mn3O4的微波加熱升溫速率，并用差重法研究了在空氣氣氛中873～1 273 K之間MnO2分解過(guò)程的動(dòng)力學(xué)。結(jié)果表明， MnO2 很容易被微波加熱， 而Mn3O4則幾乎不吸收微波； MnO2分步進(jìn)行分解： MnO2→Mn2O3→Mn3O4, 其中第一步的速率受通過(guò)產(chǎn)物層的傳熱控制，第二步受化學(xué)動(dòng)力學(xué)控制。 用微波代替?zhèn)鹘y(tǒng)方式加熱能顯著地提高分解反應(yīng)的速率，并能夠降低過(guò)程的能耗。
關(guān)鍵字: 關(guān)鍵詞: 微波 分解動(dòng)力學(xué) MnO2 Mn3O4
（1.Department of Metallurgy, Kunming University of Science and Technology,Kunming 650093, P. R. China
2.Kunming Technical College of Metallurgy, Kunming 650033, P. R. China）
Abstract:Microwave heating was used to prepare Mn3O4 from M nO2. The microwave heating rate of MnO2 and Mn3O4 was directly determined, and the kinetics of decomposition process of MnO2 was investigated by gravimetric analysis under air atmosphere in the temperature range of 873~1273 K. It is demonstrated that MnO2 can be heated well by microwaves, while Mn3O4 can not. The decomposition of MnO2 is consisted of two steps: MnO2→Mn2O3→Mn3O4, in which the first step is controlled by heat transfer through the product layer and the second by chemical kinetics. When using microwaves instead of conventional heating, the decomposition rate was significantly enhanced and the energy consumption for the process was reduced.
Key words: microwave decomposition kinetics MnO2 Mn3O4
