Further Information of the Associated Li Deposits in the No.6 Coal Seam at Jungar Coalfield, Inner Mongolia, Northern China

Abstract

Abstract:Total 138 coal samples and 14 parting samples were taken from the No. 6 Seam of the Jungar Coalfield, Inner Mongolia. These samples were analysed by optical microscopy, sequential chemical extraction procedure (SCEP), inductively coupled plasma mass spectrometry (ICP–MS), X–ray powder diffraction (XRD), and scanning electron microscope in conjunction with an energy–dispersive X–ray spectrometer (SEM–EDX) analysis. The results indicate that the Li contents have reached the industrial grade of the coal associated Li deposit, and the total Li reserves have reached 2406600 tons, that is, 5157000 tons Li2O in the No. 6 seam in the Jungar Coalfield. The sequential chemical extraction procedure results suggest that the Li concentration is mainly related to inorganic matter. The minerals in the coals consist of kaolinite, boehmite, chlorite–group mineral, quartz, calcite, pyrite, siderite and amorphous clay material. Some Li could be absorbed by clay minerals in the Li–bearing coal seam. The chlorite phase could be most likely the host for a part of Li. The Yinshan Oldland should be the most possible source of Li of the coal.

Geochemistry of Carboniferous–Permian Coal from the Wujiawan Mine, Datong Coalfield, Northern China: Modes of Occurrence, Origin of Valuable Trace Elements, and Potential Industrial Utilization

“…Due to the potential economic value, the issue of investigating the mode of occurrence of Li has become an urgent topic worldwide. Earlier studies have suggested that Li can occur both in inorganic and organic matter in coals [9,32,33,87], while other studies on the coals from the Jungar Basin indicated that Li is mainly associated with kaolinite/illite, chlorite, and boehmite [22,71,84]. However, Li mainly occurs in aluminosilicate minerals, such as kaolinite, in the coal from the Datong coalfield and Ningwu coalfield (adjacent to the Datong coalfield) [15,29].…”

“…Numerous investigations on the elemental geochemistry in coals from north China have been carried out [7][8][9][10][11][12][13][14][15][16][17][18][19] and have revealed that various valuable elements can be found in high concentrations which gives them considerable economic significance [9,15,17,[20][21][22][23]. Dai et al [24] suggested that rare metals, such as REY, Cr, Ti, Li, Be, Au, Ag, Pt, Pd, etc., have high potential for industrial utilization in some Chinese coals.…”

“…Datong coalfield is one of the most important coal-producing areas in China, and studies have been carried out on the mineralogy and geochemistry from the Carboniferous and Permian coals in, and adjacent to, the Datong coalfield [7,9,10,[16][17][18]20,[26][27][28]. Findings from these studies have shown that the sediment source is dominated by both Cambrian-Ordovician strata as well as Archean metamorphic rocks [9,10,[16][17][18]20,[26][27][28][29]. Additionally, the low temperature hydrothermal solution activities in this area have significantly influenced the abundance and modes of occurrence of trace elements present in the coal.…”

“…Moreover, it has proven possible to recover Al and Ge as valuable byproducts from coal ash [30,31]. Other studies have indicated that Li has both organic and inorganic affinities in coals [9,32,33]. According to Dai et al [10,12], clay minerals, such as boehmite and kaolinite are the main carriers of Ga.…”

“…Paleogeographic setting and location of the Datong coalfield and Yinshan Oldland in the late Paleozoic. Modified from Sun et al[9].…”