“…As one of the solid combustible minerals, coal is gradually formed after complex biochemical and physicochemical evolutions in ancient plants buried underground. , The unit chemical core structure of coal is polycyclic aromatic hydrocarbons connected by bridging bonds, such as aliphatic chains or ether bonds, and more than 95% of the organic components are chemical compounds of carbon, hydrogen, and oxygen . Coal is one of the most abundant and economically used energy resources in the world, and nearly 80 countries flow with coal minerals. , As reported by the International Energy Agency (IEA) in 2021, the global coal reserves reached 1075 billion tonnes . The top five countries in the world’s coal reserves are the United States (accounting for 23.2% of global resources), Russia (accounting for 15.1%), Australia (accounting for 14%), China (accounting for 13.3%), and India (accounting for 10.3%), and the sum of the above five countries accounted for 76% of the total global reserves .…”