Synergistic depression mechanism of Ca^(2+) ions and sodium silicate on bastnaesite flotation  

作　　者：Zhao Cao Zeyu Cheng Jieliang Wang Yongdan Cao 

机构地区：[1]Institute of Mining Engineering,Inner Mongolia University of Science and Technology,Baotou 014010,China [2]State Key Laboratory of Mineral Processing,Beijing 100160,China [3]Inner Mongolia Key Laboratory of Mining Engineering,Baotou 014010,China

出　　处：《Journal of Rare Earths》2022年第6期988-995,I0006,共9页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(51764045);the Open Project of State Key Laboratory of Mineral Processing(BGRIMM-KJSKL-2020-23);the Excellent Youth Foundation of IMUST(2017YQL05);the Inner Mongolia Natural Science Foundation(2020LH05027,2019MS05039);the Inner Mongolia Major Basic Research Open Project(0406091701)。

摘　　要：Bastnaesite is an important rare earth mineral and is usually beneficiated by flotation.Sodium silicate is commonly used to depress calcium-bearing gangue minerals,however it can also depress bastnaesite when Ca^(2+) ions exist in the pulp.In this study,the effect of Ca^(2+) ions and sodium silicate individually or in combination on bastnaesite flotation was studied through micro-flotation,zeta potential,fluorescence spectroscopy and X-ray photoelectron spectroscopy(XPS) measurements.Micro-flotation results show that the combination of Ca^(2+) ions and sodium silicate depresses bastnaesite more severely due to their synergistic effect.Zeta potential results show that the combination renders the surface potential of bastnaesite negatively shifted more significantly.Fluorescence spectroscopy shows that the combination decreases the surface hydrophobicity of bastnaesite more severely.XPS shows that the combination increases the adsorption of sodium silicate on bastnaesite by forming hydrophilic Ca-SiO_(3) precipitate,which causes more serious depression on bastnaesite flotation.

关 键 词：BASTNAESITE FLOTATION Sodium silicate Ca^(2+)ions Synergistic depression Rare earths 

分 类 号：TD955[矿业工程—选矿] TD923