(包頭稀土研究院 白云鄂博稀土資源研究與綜合利用國家重點實驗室，包頭 014030)
摘 要: 采用六水氯化鎂焙燒分解獨居石，并對其反應(yīng)機理進行研究，主要考察焙燒溫度、焙燒時間、礦鹽比對獨居石焙燒分解的影響。結(jié)果表明：根據(jù)TGA-TG、XRD、SEM、EDS和熱力學(xué)分析，六水氯化鎂首先在310 ℃分解，其分解產(chǎn)物堿式氯化鎂和氯化氫在350 ℃與獨居石反應(yīng)生成REOCl；堿式氯化鎂分解產(chǎn)物氧化鎂和氯化氫在500 ℃與獨居石反應(yīng)生成REOCl， 其在550 ℃又繼續(xù)分解生成稀土復(fù)合氧化物。焙燒溫度、焙燒時間和礦鹽比對獨居石的分解率沒有明顯影響。氯化氫和水在獨居石的分解過程中具有催化分解作用，利用此催化作用可通過分階段控制焙燒溫度來提高獨居石的分解率。
關(guān)鍵字: 稀土；獨居石；六水氯化鎂；氯化焙燒；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
