Decomposition Reaction of Mixed Rare Earth Concentrate and Roasted with CaO and NaCl  

作　　者：Wu Wenyuan Hu Guangyong Sun Shuchen Chen Xudong Tu Ganfeng 

机构地区：[1]School of Material and Metallurgy, Northeastern University, Shenyang 110004, China School of Material and Metallurgy, Northeastern University, Shenyang 110004, China School of Material and Metallurgy, Northeastern University, Shenyang 110004, China School of Material and Metallurgy, Northeastern University, Shenyang 110004, China School of Material and Metallurgy, Northeastern University, Shenyang 110004, China

出　　处：《Journal of Rare Earths》2004年第z1期53-56,共4页稀土学报（英文版）

摘　　要：The reaction of the mixed rare earth concentrate including monazite ( REPO4 ) and bastnaesite ( REFCO3 )decomposed by CaO and NaCl additives at the temperature range from 100 to 1000 ℃ was studied by means of XRD and TG-DTA.The results show that when CaO and NaCl are not added, only REFCO3 can be decomposed at the temperature of 377 ～ 450 ℃.The decomposition products include REOF, RE2O3 and CeO2.However, REFCO3 can not be decomposed.When CaO is added, the decomposition reactions occur at the temperature range from 660 to 750 ℃.CaO has three decomposition functions: ( 1 ) REPO4 can be decomposed by CaO and the decomposition products include RE2O3 and Ca3 (PO4)2; (2) CaO can decompose REOF, and the decomposition products are RE2O3 and CaF2; (3)CaO can decompose REPO4 with CaF2, and the decomposition products are RE2 O3, Ca5 F( PO4 )3.The decomposition ratio of the mixed rare earth concentrate increased obviously, when CaO and NaC1 were added.NaC1 can supply the liquid for the reaction, improve the mass transfer process and accelerate the reaction.At the same time, NaC1 participated in the reaction that REPO4 was decomposed by CaO.

关 键 词：METALLURGY technology RARE earth CONCENTRATE decomposition reaction calcium oxide sodium CHLORIDE 

分 类 号：O643.5[理学—物理化学] O614.339[理学—化学]