文献类型：期刊文献

英文题名：Direct Preparation of Water-Soluble Lithium Salts from ?-Spodumene by Roasting with Different Sulfates

作者：Qiu, Shengbo[1];Sun, Tianyu[1];Zhu, Yue[1];Liu, Chenglin[1,2];Yu, Jianguo[1,2]

机构：[1]East China Univ Sci & Technol, Natl Engn Res Ctr Integrated Utilizat Salt Lake Re, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Joint Int Lab Potassium & Lithium Strateg Resource, Shanghai 200237, Peoples R China

年份：2023

卷号：62

期号：1

起止页码：685

外文期刊名：INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH

收录：;EI(收录号：20225213315068);WOS:【SCI-EXPANDED(收录号:WOS:000904113000001)】；

基金：ACKNOWLEDGMENTS This work was supported by the National Key R&D Program of China (2021YFC2902603) and Shanghai Pujiang Program (2019PJD011) .

语种：英文

外文关键词：Additives - Calcination - Extraction - Leaching - Lithium - Lithium compounds - Magnesium compounds - Salts - Sodium sulfate - Temperature

摘要：The conventional process of lithium extraction from alpha-spodumene requires high-temperature calcination to transform alpha-spodumene into beta-spodumene, and concentrated acid roasting followed by water leaching. This study proposed the direct preparation of water-soluble lithium salts from alpha-spodumene by roasting with different sulfates to avoid the use of concentrated acid and simplify the process flow. In this study, the theoretical feasibilities of the roasting of alpha-LiAlSi2O6 with different sulfates to produce water-soluble lithium salts were first verified using HSC Chemistry 10. Then, the roasting of spodumene concentrate with CaSO4 center dot 2H2O, MgSO4 center dot 7H2O, and Na2SO4 followed by water leaching was investigated to extract lithium from alpha-spodumene. The complete transformation from alpha-spodumene to gamma- and beta-spodumene without additives occurred at 1000 degrees C for 30 min. CaSO4 center dot 2H2O did not significantly promote the phase transformation or the reaction with alpha-spodumene. MgSO4 center dot 7H2O and Na2SO4 could react with alpha-spodumene to generate water-soluble Li2Mg2(SO4)3 and LiNaSO4, respectively, but the roasting results with Na2SO4 were better than MgSO4 center dot 7H2O. Here, 93.8% Li was converted into LiNaSO4 when roasting with Na2SO4 at 1000 degrees C for 60 min with an ore/Na2SO4 mass ratio of 1:0.7. Low-temperature roasting of the concentrate with Na2SO4 and CaO was proposed to produce LiNaSO4 at 850-875 degrees C for 60 min with ore/Na2SO4/CaO mass ratios of 1:0.7:(0.05 to 0.1), and the lithium extraction efficiencies were about 86%.