Enrichment Mechanism Of Rare Metal Elementsin The Coal From Iqe Coalfield

With the increasing demand of rare metals, the development of theoretical research of coal-host rare metal deposites, and the extractive techniques of rare metals in China, Coal-host rare metals get more and more investments and researches. The geochemical characteristics of rare metals in coal and its developments and changes in geological time can reflect the evolution of coal accumulating basin and the regional geological structure. The study on coal-hosted rare metal ore deposits are not only important for rational planning and utilization of coal resources and realizing the development of coal circular economy, but also for the security of national rare metal resources.Conbining both domestic and overseas research methods and techniques of rare metal elements in coal, this article analysed the coal of BeiShan exploration area in Iqe coalfield based on Coal Petrology, Geochemistry, Mineralogy and Metallogeny and so on. The samples are analyzed by polarization microscope, SEM-EDX, XRD, ICP-MS, XRF and so on, in order to test the maceral group, minerals composition and the content of rare metal elements. The paper studied the distribution of rare metal elements, the correlationship of macerals and minerals, and discussed the source, formation, enrichment mechanism and influence factor of rare metal elements, combining the sedimentary environment of coal in Iqe coalfield and the Mineralogy.The results shows that the maceral group are mainly content vitrinite, then inertinite, last exinite in No. 6 and No. 7 coals, and the main minerals are clay minerals(kaolinite and illite), then quarts, pyrite and calcite are less, and there are trace of apatite, rutile and siderite.The Cesium is highly enriched, and the concentration coefficient(CC) of Cs is more than 10, while Ga, W, Th, V are slight enriched in No. 6 coal. Cesium and Rubidium are enriched in No. 7 coal, and the concentration coefficient of Cs and Rb are more than 5; Ga, Sr, Ba, W, Th, V are slight enriched in No. 7 coal. Both Rb and Cs are more enriched in the parting relative to coal samples, and the CC of Rb and Cs are more than 10 in parting samples. The content of LREY and MREY are enriched in both No. 6 and No. 7 coals, but HREY is normal.The correlation coefficient between ash and Ga, Rb, Zr, Nb, Cs, Hf, Ta, Th are between 0.7-1.0 in No. 6 coal, and The correlation coefficient between ash and Sc, Ga, Rb, Zr, Nb, Hf, Ta, Th are between 0.5-0.69. The high relationship with ash showing that these elements may have inorganic affinity and mostly occur in minerals, while W, Bi, U, Ni, Sr, REY may have both organic and inorganic affinity. The REY are light positive with ash, but relatively high with P2O5 in both No. 6 and No. 7 coals, indicating that rare earth elements may occure in P-beraing minerals or phosphate mineral which belong to terrigenous detrital particles.The correlation coeffient between both Rb, Cs and K2 O, ash, Al2O3, SiO2 are very high, and Rb is highly negative correlation with organic matter, while Cs is lightly positive with organic matter, showing that the occurrence of Rb and Cs most problely relative with aluminosilicate, but Cs may be influenced by organic.