1. Surface Properties and Denitrification Performance of Impurity-Removed Rare Earth Concentrate
- Author
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Yuze Bai, Zhao Zengwu, Zhijun Gong, Kai Zhang, Wenfei Wu, and Baowei Li
- Subjects
inorganic chemicals ,Materials science ,structure–activity relationship ,Scanning electron microscope ,Inorganic chemistry ,catalytic activity ,02 engineering and technology ,010402 general chemistry ,Dispersion (geology) ,rare earth concentrate ,complex mixtures ,01 natural sciences ,lcsh:Technology ,Article ,X-ray photoelectron spectroscopy ,Impurity ,Desorption ,Specific surface area ,General Materials Science ,active powder ,lcsh:Microscopy ,Roasting ,lcsh:QC120-168.85 ,lcsh:QH201-278.5 ,lcsh:T ,technology, industry, and agriculture ,food and beverages ,nh3-scr ,equipment and supplies ,021001 nanoscience & nanotechnology ,Alkali metal ,0104 chemical sciences ,lcsh:TA1-2040 ,lcsh:Descriptive and experimental mechanics ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,0210 nano-technology ,lcsh:Engineering (General). Civil engineering (General) ,NH3-SCR ,lcsh:TK1-9971 - Abstract
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&ndash, base treatment on the physical and chemical properties of the samples were analyzed by scanning electron microscopy, X-ray diffraction, Brunauer&ndash, Emmett&ndash, Teller characterization, X-ray photoelectron spectroscopy, H2-temperature-programmed reduction, NH3-temperature-programmed desorption (TPD), and NO-TPD. Results showed that the content of Ce7O12 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 Ce3+ and Ce4+, whereas Fe coexisted in the form of Fe3+ and Fe2+. The content of Fe3+ was increased. The acid&ndash, base-treated rare earth concentrates had a denitration efficiency of 87.4% at a reaction temperature of 400 °, C.
- Published
- 2020