Reaction behavior and mechanism of anatase in digestion process of diasporic bauxite  

作　　者：李小斌 付伟岸 周秋生 刘桂华 彭志宏 

机构地区：[1]School of Metallurgical Science and Engineering, Central South University

出　　处：《中国有色金属学会会刊：英文版》2010年第1期142-146,共5页Transactions of Nonferrous Metals Society of China

基　　金：Project(2005CB6237-02) supported by the National Basic Research Program of China

摘　　要：Based on the study of influence of temperature, digestion time, amount of CaO added and composition of aluminate solution on reaction behavior of pure anatase in high-pressure digestion process of bauxite, reaction mechanism of anatase was preliminarily determined. Anatase first reacts with caustic soda to produce Na2TiO3, then the resultant Na2TiO3 reacts with 3CaO·Al2O3·6H2O resulting from the reaction of CaO with sodium aluminate solution to produce CaO·2TiO2·H2O which eventually converts into CaTiO3. Higher temperature, concentration of free Na2Ok (the caustic soda uncombined with aluminate anions in the form of Na2O) and molar ratio of CaO to TiO2 are favorable to the conversion of CaO·2TiO2·H2O to CaTiO3. And Al(OH)4- shows the function of a catalyzer in the reaction of anatase with caustic soda with or without CaO added during the digestion process of diasporic bauxite.Based on the study of influence of temperature, digestion time, amount of CaO added and composition of aluminate solution on reaction behavior of pure anatase in high-pressure digestion process of bauxite, reaction mechanism of anatase was preliminarily determined. Anatase first reacts with caustic soda to produce Na2TiO3, then the resultant Na2TiO3 reacts with 3CaO·Al2O3·6H2Oresulting from the reaction of CaO with sodium aluminate solution to produce CaO·2TiO2·H2O which eventually converts into CaTiO3. Higher temperature, concentration of free Na2Ok （the caustic soda uncombined with aluminate anions in the form of Na2O） and molar ratio of CaO to TiO2 are favorable to the conversion of CaO·2TiO2·H2O to CaTiO3. And Al（OH）4^- shows the function of a catalyzer in the reaction of anatase with caustic soda with or without CaO added during the digestion process of diasporic bauxite.

关 键 词：反应机制 消化过程 锐钛型 铝土矿 行为 铝酸钠溶液 AL2O3 水 

分 类 号：TD952[矿业工程—选矿]