高氟铍矿浸出液共沉淀法除杂新工艺研究

Co-Precipitation Purification New Process for Leaching Solution of Beryllium Ore Containing High Fluorine

目前在工业上,铍金属主要是从含铍矿物中提取,主要是绿柱石、硅铍石、羟硅铍石等。随着铍矿产资源的日益枯竭,必须寻找其他替代铍矿的资源,使铍矿物的使用范围继续扩大。然而,这些替代铍矿一般含有大量的萤石,矿石中氟含量很高;在生产工业氧化铍的冶炼过程中,通常要求矿石中氟铍比小于10%,矿石中的氟含量高,严重影响工业氧化铍的质量和冶炼回收率。因此如何脱除矿石浸出液中的氟,消除氟对冶炼过程的影响,是高氟铍矿冶炼过程的难点。本文对高含氟铍矿石浸出液净化工艺进行研究,提出以共沉淀法对含铍浸出液进行净化。研究了在沉淀过程中,终点p H、温度、时间以及硫酸铵浓度等因素的影响;共沉淀条件为：p H=3.5~4.0、温度95℃、时间6 h、沉淀剂氨水浓度10%,沉淀经0.5 mol·L-1的硫酸铵溶液浆化洗涤;在此过程中,杂质铝、氟、铁的沉淀率在97%以上,铍的损失率在10%左右。

Beryllium is usually extracted from mineral ores at present, and the minerals are mainly beryl, bertrandite or phenakite, etc. With the increasing depletion of beryllium mineral resources, alternative beryllium mineral resources should be sought, thus the exploita- tion of beryllium minerals continues to expand. However, these alternative beryllium minerals generally contain large amounts of fluorite, and the content of fluorine is very high in the ores ; in the smelting process for producing industrial beryllium oxide, it is usually required that the fluorine to beryllium ratio of these minerals is less than 10%, and if the fluorine content in the minerals is high, it will seriously affect the quality of industrial beryllium oxide and smelting recovery rate. Therefore, it is the key to remove fluoride from leaching solu- tion and thus eliminate the effect of fluoride during the fluoride beryllium minerals smelting process. The purification process of high fluo- rine beryllium minerals leaching solution was studied, and a co-precipitation method of purifying beryllium-containing leach solution was put forward. In the purification process, the influencing factors such as final pH, temperature, time, and concentration of ammonium sul- fate were studied. The co-precipitation conditions were： pH =3.5 -4.0, temperature of 95 ℃, time of 6 h, precipitant（ammonia） con- centration of 10%. The precipitate was slurried and washed using 0. 5 tool·.L-1 ammonium sulfate. In this process, the impurity precipi- tation rates of aluminum, fluorine, iron were more than 97%, and the loss rate of beryllium was about 10%.