铝土矿(岩)中伴生的锂资源

The associated lithium resource in bauxite(bauxite-bearing rock)

我国铝土矿资源丰富,铝土矿在成矿过程中通常会富集锂(Li)等对现代工业至关重要的关键金属元素,成矿潜力巨大。铝土矿(岩)中的Li主要富集在矿体顶底板的铝土岩或黏土岩以及低品质铝土矿矿石中,而这些正是铝土矿开采过程中产生的无用的尾矿,对其中伴生的Li加以利用,不仅能进一步提高铝土矿矿山的价值,还能改善矿山环境污染及缓解我国Li资源短缺的状况。目前针对铝土矿(岩)中伴生Li的赋存状态的研究还比较薄弱,争议较大。已有的研究指出Li在铝土矿(岩)中可能以离子吸附的形式赋存在黏土矿物和铁锰氧化物表面或以类质同象的形式替代镁铁硅酸岩矿物、黏土矿物及铁锰矿物晶格中的Mg^(2+)和Fe^(2+)。而铝土矿(岩)中是否存在独立矿物,如类似粘土岩中的锂绿泥石,还缺少实际证据。铝土矿(岩)中Li的富集规律与铝土矿的成矿过程关系密切,物源、沉积古地理、气候、沉积环境和矿物的分化及新矿物的形成都可能是控制Li活化、迁移和富集的主要因素,但目前相关研究还十分薄弱。铝土矿(岩)伴生的Li有可能成为我国锂矿资源开发利用的另一个重要发展方向,开展相关研究,不仅可以为铝土矿中伴生Li的综合利用和评价提供依据,而且也将拓宽我国Li矿资源开发利用思路。

China is rich in bauxite ores in which Li and other metals critical to the modern industry are commonly enriched.Moreover,it has been widely found that Li is highly enriched in bauxite-bearing rock series.Therefore,there is great potential of Li resource in bauxite(bauxite-bearing rock).In addition,Li is mainly concentrated in bauxite-bearing rocks or claystone at the roof and floor of bauxite orebodies and low quality bauxite ores,which are general useless tailings produced in the process of mining.Therefore,the utilization of associated Li resources in the bauxite deposit can not only raise values of bauxite ores(bauxite-bearing rocks),but also can reduce the environmental pollution of mines and alleviate the shortage of lithium resources in China.The occurrence state of associated Li in bauxite(bauxite-bearing rock)is still controversial due to poor previous studies.It has been proposed that Li could be adsorbed on the surfaces of clay minerals and Fe-Mn oxides in bauxite ore(bauxite-bearing rock)by ion adsorption,or could substitute Mg^(2+)and Fe^(2+) in the lattice of mafic silicate minerals,clay minerals and iron manganese minerals in the form of isomorphism.In addition,it is not known whether there are independent Li minerals,such as cookeite found in claystone,in bauxite(bauxite-bearing rock)due to the lack of actual evidence.The enrichment regularity of Li in bauxite(bauxite-bearing rock)is closely related to the mineralization process of bauxite.Provenance,sedimentary paleogeography,palaeoclimate,sedimentary environment,mineral differentiation,and the formation of new minerals could be the main factors controlling the activation,migration,and enrichment of Li.However,those relevant researches are extremly weak at present.The associated Li in bauxite(bauxite-bearing rock)may become another important direction of development and utilization of lithium resources in China.Those relevant researches will not only provide the basis for the comprehensive utilization and evaluation of the associated Li resource in bauxite(bauxite-bearing rock),but also expand the way of thinking on the development and utilization of Li resource in China.