包头磁尾矿稀土浸出和制备冰晶石的研究

包头白云鄂博矿床产生大量磁尾矿,会产生很大的环境问题。采用纯碱焙烧法对其进行了稀土浸出实验和氟的资源化利用研究。实验结果表明,包头磁尾矿与纯碱混合物于700℃焙烧1.0 h,经稀盐酸洗涤后,以3.0 mol.L-1稀硫酸于65℃下浸出4.0 h,氟的洗脱和稀土浸出效果较好,其中稀土浸出率为97.97%,氟浸出率为99.54%,氟洗脱率为77.32%。以该条件下产生的含氟废水为原料,于90℃下制备了冰晶石,溶液中氟回收率为85.63%,并推算出磁尾矿中氟的总利用率为66.21%。该法使磁尾矿由废弃物变为二次资源成为可能。

Leaching of Rare Earth and Preparation of Cryolite from Baotou Magnetic Tailings

Baotou Baiyunebo deposit produces a large number of magnetic tailings,resulting in serious environmental problems.In this paper,the rare earth leaching experiment and fluorine recycling research were carried out by soda roasting method.The results showed that the Baotou magnetic tailings/soda mixture roasting at 700 ℃ for 1 h,washing with dilute hydrochloric acid,leaching at 65 ℃ with 3.0 mol·L-1 sulfuric acid for 4.0 h had better fluorine elution and RE leaching effect,and the RE leaching rate was 97.97%,fluorine leaching rate was 99.54%,and the fluorine elution rate was 77.32%.With produced containing fluorine wastewater as raw materials under above condition,the cryolite was prepared at 90 ℃.The recovery rate of fluorine in the wastewater was 85.63%,thus calculated the total utilization rate of fluorine in magnetic tailings was 66.21%.This method made it possible to turn the magnetic tailings from waste into secondary resource.