Preparation of Battery-Grade Lithium Composites from Local Spodumene

Nowadays lithium metal is considered as one of the key elements in modern industry. Its usages range from pharmacy to aeronautics including energy storage devices and glass-ceramics. However, since 2005, Lithium-ion Batteries (LiBs) have taken over, as they play a major role in the development of the electronic and green industries [1]. LiBs show the highest growth rate and are expected to take an even bigger part in the lithium industry. The expected growth rate for lithium carbonate and lithium hydroxide is respectively 10% and 14.5% until 2025 [2], since they are two of the raw materials used for LiBs. In 2016, lithium carbonate prices were reported to range from 10,000 US$ to 16,000 US$ while lithium hydroxide prices were reported to range from 14,000 US$ to 20,000 US$ [3]. The lithium production was, until recently, dominated by the Salt Lake brines, because of their cheaper production cost. The ever-growing demand in lithium compounds led to the regaining of interest for another source, after the lithium price increased. This other source, lithium rich minerals, now account for 50% of the world’s lithium production [4]. Lithium minerals are numerous and include spodumene, eucryptite, petalite, bikitaite, etc. [5]. Among those minerals, spodumene LiAlSi2O6 is the most common and the most studied. It offers a theoretical Li2O content of 8 wt %, whereas raw minerals in nature typically offer 1 to 2 wt % Li2O. In Kazakhstan, all known lithium reserves are associated with spodumene and according to U.S. Geological Survey, Mineral Commodity Summaries made in January 2020, Kazakhstan has approximately 50000 tons of lithium [6]. And according to the Kazakh National Technical University, lithium in the process of operation is usually not separately extracted and all goes into the waste "tailings" of the deposits. In this work preliminary results on the development of the optimal leaching process of lithium composites from Kazakhstani spodumene will be presented. The new process offers a fast throughput, direct leach process for spodumene concentrates to produce battery grade lithium hydroxide and / or lithium carbonate monohydrate products. The process is also environmentally sustainable. The leach process is totally sulfate and acid free and the refining process does not involve any crystallization of unnecessary by-product salts. [1] Sociedad Quimica y Minera de Chile, 2003 to 2013, Annual Reports; SQM: Santiago, Chile, 2003–2013 [2] SignumBOX. Analysis: Lithium, Batteries and Vehicles/Perspectives and Trends; SignumBOX: Santiago, Chile, 2014; p. 8 [3] Jaskula, B.W. Lithium, 2016 Mineral Yearbook 2018; USGS: Reston, VA, USA, 2018; p. 44.1 [4] U.S. Geological Survey. Mineral commodity summaries 2016: U.S. Geological Survey Lithium; USGS: Reston, VA, USA, 2016; p. 202 [5] Labbé, J.F.; Daw, G. Panorama 2011 du marché du lithium; Rapport public 2012, BRGM/RP-61340-FR; BRGM: Orléans, France, 2012; p. 94 [6] U.S. Geological Survey, 2020, Mineral commodity summaries 2020: U.S. Geological Survey, 200 p., https://doi.org/10.3133/ mcs2020