title: Recovery of fluorine from bastnasite as synthetic cryolite by-product.
abstract: This paper investigates the development of a new environment friendly approach for treatment of bastnasite. A new process was developed to recover fluorine from bastnasite as synthetic cryolite by-product. The conditions affecting the fluorine removal and recovery in the process, including contact time, acidity, Al(3+) concentration, Al/F molar ratio and different kinds of aluminum salts being used, were investigated. The results indicate that high acidity and large Al/F molar ratio were beneficial to fluoride removal, and that the reaction reached equilibrium after 15 min. The effect of the initial Al(3+) concentration at a certain total Al(3+) amount was slight. Aluminum nitrate was more efficient than aluminum sulfate for the removal of fluoride. Optimum operation parameters for synthesizing cryolite have been obtained and proposed for industrial applications.
authors.affiliation: National Engineering Research Center for Rare Earth Materials, General Research Institute for Nonferrous Metals, and Grirem Advanced Materials Co. Ltd., Beijing 100088, PR China.
authors.forename: Liangshi
authors.initials: L
authors.lastname: Wang
authors.forename: Chunmei
authors.initials: C
authors.lastname: Wang
authors.forename: Ying
authors.initials: Y
authors.lastname: Yu
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Huang
authors.forename: Zhiqi
authors.initials: Z
authors.lastname: Long
authors.forename: Yongke
authors.initials: Y
authors.lastname: Hou
authors.forename: Dali
authors.initials: D
authors.lastname: Cui
mesh_terms: D002586:Cesium / Q000737:chemistry*; D018360:Crystallography, X-Ray; D005461:Fluorine / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007811:Lanthanum / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008903:Minerals / Q000737:chemistry*; D012969:Sodium Fluoride / Q000737:chemistry*
chemical_list: D008903:Minerals; D002586:Cesium; D005461:Fluorine; C007157:cryolite; D007811:Lanthanum; D012969:Sodium Fluoride