A novel and efficient microwave oxidation roasting method for preparing ammonium molybdate from molybdenum concentrate has been proposed and compared with the conventional roasting. TG-DTG, XRD, SEM-EDS, EDX and FTIR methods were used for characterization and analysis of oxidation roasting of ammonium molybdate. Based on the results of thermodynamic and dielectric properties of molybdenum concentrate, the effects of roasting temperature, roasting time, material mass and microwave power density on the oxidation degree of molybdenum concentrate were investigated. The influence of leaching agent, the concentrations of nitric acid and ammonia water on the leaching of ammonium molybdate was investigated. Under the same roasting conditions, the degree of oxidation of molybdenum concentrate by microwave roasting was higher than that of conventional roasting. Microwave roasting reduce the heating time of 30 min to reaction temperature and save 2.0 kW/h power in each roasting experiment. The optimal roasting and leaching conditions are as follows: roasting temperature of 600°C, roasting time of 2 h, power density of 100 W/g, nitric acid concentration of 0.80 mol/L, ammonia concentration of 25%. The purity and crystallinity of (NH₄)₆Mo₇O₂₄∙4H₂O prepared by microwave roasting molybdenum concentrate are higher and better stability.

提出了一种从钼精矿制备钼酸铵的新型高效微波氧化焙烧方法，并与传统焙烧方法进行了比较。采用TG-DTG、XRD、SEM-EDS、EDX和FTIR方法对钼酸铵氧化焙烧进行表征和分析。基于钼精矿的热力学和介电性能结果，研究了焙烧温度、焙烧时间、物料质量和微波功率密度对钼精矿氧化程度的影响。考察了浸出剂、硝酸和氨水浓度对钼酸铵浸出的影响。在同样的烘焙条件下，微波焙烧对钼精矿的氧化程度高于常规焙烧。微波焙烧减少了30分钟的加热时间到反应温度，在每次焙烧实验中节省了2.0 kW/h的功率。最佳焙烧浸出条件为：焙烧温度600℃，焙烧时间2h，功率密度100W/g，硝酸浓度0.80mol/L，氨气浓度25%。(NH的纯度和结晶度₄ ) ₆ Mo ₇ O ₂₄ ∙4H ₂ O 微波焙烧钼精矿制备得到的钼精矿含量更高，稳定性更好。