Occurrence of antimony in magmatic intrusive coal seam：A case study from the Wolonghu coal mine, Huaibei coalfield, China

In order to investigate the influence of magmatic alteration on the occurrence characteristics of antimony in coal seam, 12 samples of magmatic magma and coal were collected from Wolonghu coal mine in Huaibei coalfield, Anhui Province, and the content of Sb was determined by atomic fluorescence spectrometry(AFS). The coal quality parameters are analyzed. The results are as follows: the coal in Wolonghu magmatic intrusion area has the characteristics of ultra-low volatile matter, medium ash content and ultra-low sulfur content. And the main forms of sulfur in coal are organic sulfur and pyrite sulfur. Under the influence of magmatic hydrothermal solution, ash in coal seam increases and volatile content decreases. The content of antimony in Wolonghu coal mine is obviously enriched, with an average of 10.48 mg/kg. The average content of Sb in the coal above the intrusive rock is obviously increased, and the content of Sb in the contact zone of coal and rock reaches the highest value(13.93 mg/kg). The antimony in magmatic altered coal mainly exists in the form of inorganic binding(r=0.74), while organic sulfur is negatively correlated with Sb in coal(r=-0.60). The magmatic intrusion resulted in the coal quality characteristics and the occurrence of antimony in Wolonghu coal mine. This result enriches the environmental geochemical study of antimony in coal under special geological process.