摘要
The kinetics of carbon reduction of ZnFe2O4 in the temperature range of 550-950 °C was investigated in a microwave tank-type reactor. The mechanism of formation of ZnO and Fe3O4/FeO by the decomposition of ZnFe2O4 was detailed using the equilibrium calculations and thermodynamics analysis by HSC chemistry software 6.0. In addition, the effects of decomposition temperature, the C/ZnFe2O4 ratio, the particle size and the microwave power were assessed on the kinetics of decomposition. Zn recovery as high as 97.93%could be achieved at a decomposition temperature of 750 °C with C/ZnFe2O4 ratio of 1：3, particle size of 61-74 μm and microwave power of 1200 W. The kinetics of decomposition was tested with different kinetic models and carbon gasification control mechanism was identified to be the appropriate mechanism. The activation energy for the carbon gasification reaction was estimated to be 38.21 kJ/mol.
研究550-950°C下微波加热配碳还原焙烧分解铁酸锌生成ZnO和Fe3O4/FeO的工艺及机理。利用HSC热力学软件对铁酸锌分解的热力学温度进行计算，并利用碳气化控制、化学控制及扩散控制模型研究样品中铁酸锌分解的动力学行为。分析微波功率、反应温度、配碳比和时间对铁酸锌分解率的影响。结果表明：在微波加热温度750°C，C/ZnFe2O4质量比为1：3，粒径74~89μm，微波功率1.2 kW的条件下，被还原的铁酸锌样品经过浸出后，Zn的回收率可以高达97.93%。通过采用不同的动力学模型对分解动力学进行测试。结果表明：碳气化控制机制是良好的机制。碳气化反应的活化能为38.21 kJ/mol。
基金
Projects (51004059,E041601) supported by the National Natural Science Foundation of China
Project (14051157) supported by Natural Science Foundation of Yunnan Province
