摘要
通过考察不同试剂和条件对白云鄂博尾矿中钪的浸出率的影响,对钪的提取工艺进行了研究,旨在寻求一种最佳浸出方法,以实现钪的提取和资源综合利用。以白云鄂博尾矿为研究对象,将进一步选除稀土、铁、萤石之后的尾矿作为试验原料,通过不同体系酸直接浸出试验、焙烧后盐酸浸出试验、加入不同焙烧剂焙烧后盐酸浸出试验等方法,对原料中的钪进行浸出,以研究不同试剂和不同条件对钪浸出率的影响。试验数据表明,钪的浸出率随酸度的升高而上升,当酸度为12 mol·L-1时,盐酸体系中钪的浸出率为21.2%,硫酸体系中钪的浸出率为13.4%,硝酸体系中钪的浸出率为8.3%;加入不同焙烧剂焙烧后盐酸浸出试验中,碳酸钠和氟化氢铵对钪的浸出率影响不大,浸出率分别为24.6%和25.3%,氢氧化钠对钪的浸出效果有明显提高,浸出率为69.8%。综合考虑钪的浸出率和生产成本两方面因素,确定该工艺的最佳条件如下:焙烧温度为350℃,焙烧时间为2.5 h,矿碱比例为1∶1.2,盐酸体积为500 mL,盐酸浓度为3.5 mol·L-1,浸出时间为2.0 h。最优条件下的浸出率为99%以上。
The process of extracting scandium from Bayan Obo tailings was studied by investigating the leaching rate of scandium with different reagents and in different conditions. It is aimed at finding an optireal leaching method to achieve the extraction of scan- Bayan Obo mine tailings and comprehensive utilization of resources. This research used the Bayan Obo mine tailings as an object of study, through the test of leaching scandium with different acid directly, leaching scandium with hydrochloric acid after calcinating the tailing with different additives. The effects of different reagents and different conditions on leac hing rate of scandium were studied. The data of experi- ment showed that the leaching rate of scandium increased with increasing of the concentration of acid. When the concentration of acid was 12 mol ·L^-1, the leaching rates of scandium were 21. 2%, 13.4% , 8.3 %, respectively, when the applied acids were hydrochloric acid, sulfuric acid and nitric acid respectively. In the test of leaching scandium from calcinated tailing with different additives by hydrochloric acid, it was found that there was a little effect when sodium carbonate or ammonium bifluoride was added in, and the leaching rate of scandium was 24.6% and 25.3% respectively, the effect of adding sodium hydroxide was remarkable and the leaching rate was 69. 8%. Based on considerations of cost and process conditions, the optimal process of extraction scandium from tailings is that： the calcinating temperature is 350 ℃, the roasting time was 2.5 h, the mass ratio of tailing-alkali is 1 ： 1.2, the volume of hydrochloric acid is 600 mL, and the concentration of hydrochloric acid is 3.5 mol·L^-1 , the leaching time is 2.0 h. The leaching rate of scandium is more than 99%.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2013年第6期703-709,共7页
Journal of the Chinese Society of Rare Earths
基金
"十二五"国家科技支撑计划(2012BAE01B01)
国家高技术研究发展计划(863计划)(2012AA061904)
国家杰出青年基金(51045216)
973计划前期研究专项(2011CB411911)资助
关键词
白云鄂博
尾矿
钪
盐酸浸出
Bayan Obo
railings
scandium
hydrochloric acid leaching
