Zhang Kai, Bai Yuze, Gong Zhijun, Zhao Zengwu, Li Baowei, Wu Wenfei
College of Environment and Energy, Inner Mongolia University of Science and Technology, Baotou 014000, Inner Mongolia, China.
Key Lab Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources, Baotou 014000, Inner Mongolia, China.
Materials (Basel). 2020 Jan 26;13(3):580. doi: 10.3390/ma13030580.
Acid leaching and alkali roasting were used to remove impurities such as Ca and Si in Baiyun Obo rare earth concentrate. The effects of acid-base treatment on the physical and chemical properties of the samples were analyzed by scanning electron microscopy, X-ray diffraction, Brunauer-Emmett-Teller characterization, X-ray photoelectron spectroscopy, H-temperature-programmed reduction, NH-temperature-programmed desorption (TPD), and NO-TPD. Results showed that the content of CeO in the rare earth concentrates increased and the dispersion was uniform. The grains became smaller, the specific surface area of rare earth concentrates increased, and the active sites were more exposed. Ce coexisted in the form of Ce and Ce, whereas Fe coexisted in the form of Fe and Fe. The content of Fe was increased. The acid-base-treated rare earth concentrates had a denitration efficiency of 87.4% at a reaction temperature of 400 °C.
采用酸浸和碱焙烧法去除白云鄂博稀土精矿中的钙、硅等杂质。通过扫描电子显微镜、X射线衍射、布鲁诺尔-埃米特-泰勒表征、X射线光电子能谱、氢气程序升温还原、氨气程序升温脱附（TPD）和一氧化氮TPD分析了酸碱处理对样品物理化学性质的影响。结果表明，稀土精矿中CeO含量增加且分散均匀。晶粒变小，稀土精矿比表面积增大，活性位点更多暴露。Ce以Ce和Ce的形式共存，而Fe以Fe和Fe的形式共存。Fe含量增加。酸碱处理后的稀土精矿在400℃反应温度下脱硝效率为87.4%。
