印度洋海盆沉积物中稀土的赋存状态及其浸出研究  

Study on the Occurrence State and the Leaching of Rare Earth Elements in Sediments of the Indian Ocean Basin

作　　者：潘炳[1] 任国兴[1] 王祥[1] 姜楚灵[1] 麦笑宇[1] 钟志刚 PAN Bing;REN Guoxing;WANG Xiang;JIANG Chuling;MAI Xiaoyu;ZHONG Zhigang(Changsha Research Institute of Mining and Metallurgy Co.,Ltd.,Changsha 410012,China)

机构地区：[1]长沙矿冶研究院有限责任公司,湖南长沙410012

出　　处：《金属矿山》2020年第11期84-89,共6页Metal Mine

基　　金：中国大洋协会“十三五”深海矿产资源选冶研究课题(编号:JS-KTHT-2018-05)。

摘　　要：印度洋海盆沉积物作为重要的稀土资源,已成为保障我国稀土供应的重要途径。为探究利用印度洋海盆沉积物提取稀土的可行性,通过激光粒度分析、化学物相分析、SEM分析等考察了某印度洋海盆沉积物中稀土元素赋存状态,并采用硫酸为浸出剂,研究硫酸浓度、液固比、浸出温度及时间对稀土浸出率的影响,对最佳条件下获得的浸出液通过氨水中和沉淀净化。结果表明:①沉积物颗粒极细,体积平均粒径仅4.47μm,其主要矿物组成为黏土、锰氧化物、石英、长石、云母、绿泥石和石盐,其中稀土主要赋存于磷灰石中,占总稀土比例达73.10%;②在硫酸浓度2 mol/L,液固比7∶1,浸出温度55℃,浸出时间120 min的最佳条件下,主要稀土元素La、Ce、Nd和Y的浸出率分别为80.57%,66.33%,88.42%和93.25%,高价值的重稀土Gd、Dy和Er浸出率分别为92.63%、55.30%和93.17%。③稀土浸出液成分复杂,且稀土含量偏低,仅有100 mg/L左右,采用氨水调节pH值至5.14,可有效去除Al和Fe,但稀土损失率也达到了30.85%。该研究结果对进一步开发利用深海稀土资源具有重要意义。As an important rare earth resource,sediments in the Indian Ocean basin have become an important way to guarantee the supply of rare earth in China.In order to explore the feasibility of the ultilization of the sediments in the Indian Ocean basin,the occurrence state of rare earth elements was characterized by means of MLA,chemical phase and SEM analysis,and sulfuric acid was used as leaching reagent to investigate the effect of sulfuric acid concentration,ratio of liquid to solid,leaching temperature and time on the leaching rate of the rare elements.The purification of the leaching solution in the best condition was conducted by ammonia.The results showed that:①sediment particles are extremely fine with a mean volumetric particle size of 4.47μm,and mainly consist of clay,manganese oxide,quartz,feldspar,mica,chlorite and halite.Rare earth mainly occurs in apatite,accounting for 73.10%.②The leaching efficiencies of La,Ce,Nd,Y,Gd,Dy and Er were 80.57%,66.33%,88.42%,93.25%,92.63%,55.30%and 93.17%,respectively,under the best conditions of 2 mol/L H2 SO4,ratio of liquid to solid of 7∶1,leaching temperature of 55°C and leaching time of 120 min.③The composition of rare earth leaching solution is complex,and the content of rare earth is low with only about 100 mg/L.Most of Al and Fe in the leaching solution was effectively removed when the pH of the leachate was controlled at 5.14 by adding ammonia water,while the loss rate of rare earth was more than 30.85%.The research results is significant for the further development and ultilization of the deep-sea rare earth resources.

关 键 词：印度洋 稀土 赋存状态 浸出 净化 

分 类 号：TD955[矿业工程—选矿]