Simultaneous recovery of rare earth elements and phosphorus from phosphate rock by phosphoric acid leaching and selective precipitation: Towards green process
Simultaneous recovery of rare earth elements and phosphorus from phosphate rock by phosphoric acid leaching and selective precipitation: Towards green process
复制标题
磷酸浸出和选择性沉淀从磷矿中同时回收稀土元素和磷：迈向绿色工艺
DOI：
10.1016/j.jre.2018.09.012
复制
发表时间：
2019-06-01
影响因子：
4.9
通讯作者：
Cui, Dali
中科院分区：
文献类型：
--
作者：
Wu, Shengxi;Zhao, Longsheng;Cui, Dali
磷矿被认为是稀土元素的潜在资源之一。但矿石中稀土含量低所带来的成本问题和技术挑战，确实阻碍了稀土回收技术的进一步发展。为探索从磷矿石中回收稀土的绿色工艺，本研究考察了磷酸浓度、液固比（L/S）、浸出时间和浸出温度对磷矿石中主要组分浸出效率的影响。REE5恢复94.3%和95.3%的磷复苏实现最优条件下攻击磷矿使用30% p (2) O(5) 5酸10:1的L / S比值和搅拌速度250 r / min在25摄氏度4 h。然后,里斯里斯恢复81.3%的选择性沉淀是意识到通过加热浸出溶液从25到90摄氏度,4 h。此后,超过95%磷酸是恢复了硫酸和高纯度石膏,超过95%的CaSO4（通过XRF测试）也同时产生。最后，提出了用H3PO4浸出磷矿，加热选择性地从浸出液中析出稀土元素，用H2SO4回收H3PO4的绿色工艺。与传统稀土回收工艺相比，该工艺具有操作简单、节能、废弃物少的优点。(C) 2019年由Elsevier B.V.代表中国稀土学会出版。
Phosphate rock has been considered as one of the potential promising resources for rare earth elements (REEs). But the cost issues and the technical challenges caused by the low content of REEs in ores did hinder the further development of REEs recovery technologies. In order to explore a green process for the recovery of REEs from phosphate rock, this study investigates the effects of phosphoric acid concentration, liquid-to-solid ratio (L/S ratio), leaching time and temperature on the leaching efficiencies of the major components from phosphate rock. A REE5 recovery of 94.3% and a phosphorus recovery of 95.3% are achieved under the optimal conditions of attacking phosphate rock using 30%P(2)O(5)5 acid with an L/S ratio of 10:1 and a stirring speed of 250 r/min at 25 degrees C for 4 h. Then, the selective precipitation of REEs with 81.3% REEs recovery is realized by heating up the leaching solution from 25 to 90 degrees C and keeping for 4 h. Thereafter, more than 95% phosphoric acid is recovered by H2SO4 and high purity gypsum, more than 95% CaSO4 (tested by XRF), is also produced at the same time. Ultimately, a green process that leaches phosphate rock with H3PO4, selectively precipitates REEs from leaching solution by heating up, recovers H3PO4 with H2SO4 is proposed. Compared with REE recovery in traditional processes, this process owns the merits of simple operation, energy saving and minimum wastes. (C) 2019 Published by Elsevier B.V. on behalf of Chinese Society of Rare Earths.