(包头稀土研究院 白云鄂博稀土资源研究与综合利用国家重点实验室，包头 014030)
摘 要: 采用六水氯化镁焙烧分解独居石，并对其反应机理进行研究，主要考察焙烧温度、焙烧时间、矿盐比对独居石焙烧分解的影响。结果表明：根据TGA-TG、XRD、SEM、EDS和热力学分析，六水氯化镁首先在310 ℃分解，其分解产物碱式氯化镁和氯化氢在350 ℃与独居石反应生成REOCl；碱式氯化镁分解产物氧化镁和氯化氢在500 ℃与独居石反应生成REOCl， 其在550 ℃又继续分解生成稀土复合氧化物。焙烧温度、焙烧时间和矿盐比对独居石的分解率没有明显影响。氯化氢和水在独居石的分解过程中具有催化分解作用，利用此催化作用可通过分阶段控制焙烧温度来提高独居石的分解率。
关键字: 稀土；独居石；六水氯化镁；氯化焙烧；催化冶金
（State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization, Baotou Research Institute of Rare Earth, Baotou 014030, China）
Abstract:The clean roasting technology and reaction mechanism for monazite with MgCl2·6H2O were investigated. The effects of roasting temperature, roasting time and salt mineral ratio on monazite extraction ration were researched by means of thermal differential scanning calorimetry, gravimetric analysis, X-ray diffraction, scanning electron microscopy and energy spectrum analysis. The results of the experiments are as follows: MgCl2·6H2O is decomposed to Mg(OH)Cl and HCl at 310 ℃, which react with monazite to form REOCl at 500 ℃, then REOCl is decomposed into REO. The decomposition rate of monazite does not increase obviously with the increase of roasting temperature, roasting time and ore-salt ratio. Monazite is catalyzed by HCl and H2O from MgCl2·6H2O, so it can be improve the decomposition rate of monazite by controlling the roasting temperature in stages.
Key words: rare earth; monazite; magnesium chloride hexahydrate; chloride roasting; catalytic metallurgy
