稀土粗精矿的低温硫酸化分解工艺  

Decomposition process of rare earth rough concentrate by low temperature sulfation

作　　者：刘勇[1,2] 刘珍珍[1,2] 刘牡丹[1,2] 

机构地区：[1]广州有色金属研究院资源综合利用研究所,广州510650 [2]广州有色金属研究院稀有金属分离与综合利用国家重点实验室,广州510650

出　　处：《中国有色金属学报》2014年第12期3147-3154,共8页The Chinese Journal of Nonferrous Metals

基　　金：广东省科技计划项目(2011B050400008)

摘　　要：对物理选矿和化学选矿得到的两种稀土粗精矿进行低温酸化工艺研究,通过正交和单因素实验研究酸矿比(浓硫酸与稀土精矿的质量比)、酸化时间、酸化温度以及液固比对稀土浸出效果的影响。结果表明,酸矿比、酸化时间和酸化温度对稀土粗精矿稀土浸出率的影响显著,最佳条件如下:酸矿质量比1.8:1(精矿Ⅰ)和0.9:1(精矿Ⅱ),酸化时间2.0 h(精矿Ⅰ)和3.0 h(精矿Ⅱ),酸化温度150℃。在优化的酸化和浸出条件下,稀土的浸出率分别为90.42%(精矿Ⅰ)和91.35%(精矿Ⅱ)。为研究影响稀土溶出的因素,采用MLA工艺矿物学自动检测系统对优化条件下两种粗精矿酸化浸出后的残渣进行矿物组分的定性分析,证明稀土与硫酸钙形成了复杂难溶硫酸复盐,这是影响稀土浸出率的关键因素。A decomposition process for two rare earth rough concentrates obtained by physical and chemical floatation at low temperature was investigated. The effects of ratio of acid to concentrate （mass ratio of sulfuric acid to RE concentrate）, acidification duration, acidification temperature and liquid-to-solid ratio on the leaching rate of rare earth concentrates were investigated by the orthogonal test and single factor test. The results show that mass ratio of concentrate to acid, acidification duration and acidification temperature have significant effects on the leaching rate of the rare earth concentrates, and the optimum conditions are as follows：mass ratio of concentrate to acid of concentratesⅠandⅡare 1.8：1 and 0.9：1, respectively, durations of concentratesⅠandⅡare 2.0 and 3.0 h, respectively, temperatures are both 150 ℃. Under the optimized leaching conditions, the rare earth leaching rates of concentrates Ⅰ and Ⅱ are 90.42%and 91.35%, respectively. The process mineralogy of automatic quantitative mineral technology MLA was used to test the decomposed residues of the two concentrates in order to find out the influencing factors on rare earth leaching rate, and the results prove that it is the critical influence on rare earth leaching rate that rare earth and calcium sulfate form the complex insoluble sulfate.

关 键 词：稀土粗精矿 浸出 酸化 浸出率 

分 类 号：TF845[冶金工程—有色金属冶金]