Microstructure of Coal Gangue and Precipitation of Heavy Metal Elements

Table 2

Chemical composition of coal gangue (%).

Sample	Na2O	MgO	Al2O3	SiO2	K2O	CaO	Fe2O3	P	S
Fresh coal gangue	0.65	1.8	20.7	59.9	2.4	2.0	6.7	0.05	1.53
Weathered coal gangue	0.41	1.4	17.6	53.7	2.0	1.3	5.4	0.06	0.44
	F	Ba	Mn	Cu	Pb	Zn	Ti	Cl	F
Fresh coal gangue	≤0.045	0.10	0.054	0.0006	<0.0002	0.009	0.50	0.011	≤0.045
Weathered coal gangue	<0.045	≤0.002	0.043	0.0005	<0.0002	0.005	0.42	0.009	<0.045