Adsorption Characteristics Of Mn(?) On Typical Sedimentary Rocks Of Coal Measures

It is one of the key technologies to realize the co-mining of coal and water in the western mining area by using the fractured rock mass in the mined out area of the coal mine to store the mine water,in order to realize the recycling of water.However,when mining sulfur bearing coal seam,it is easy to dissolve the minerals containing Mn(II)into the groundwater,thus increasing the concentration of Mn(II),which is likely to pollute the mine water.Among the many ways to deal with Mn(II),adsorption is one of the cheapest and cheapest methods of water purification.Coal mine goaf gangue is rich in clay minerals,and clay minerals have a good adsorption effect on Mn(II)because of its hydroxy group,negative charge structure and larger specific surface area.Taking the mudstone and sandstone of top and floor in the goaf of Mei Hua Jing coal mine and Wulan Mulun coal mine as the research object,the isothermal adsorption characteristics of the rock samples to Mn(II)are studied by Batch method.The results show that the rock samples have strong adsorption capacity to Mn(II),and the adsorption capacity is predicted by the Langmuir equation.The adsorption of mudstone and fine sandstone are 3.311 mg/g and 2.750 mg/g,respectively.The adsorption kinetics characteristics are discussed.The adsorption rate of Mn(II)is very fast,and the adsorption equilibrium state can be reached within 5 min.The adsorption thermal dynamic characteristics are explored.It is found that the adsorption of Mn(II)increases with the temperature rise,and it can be judged.The adsorption reaction is a endothermic reaction.According to the fitting parameters of the thermal dynamic equation,the adsorption of Mn(II)ions can be carried out spontaneously and Mn(II)has a strong affinity.The effect of p H on the adsorption is studied.It is found that when p H is less than 4,the adsorption capacity of the rock samples to Mn(II)is significantly reduced,and the sand shale and fine sand containing carbon chips and fine sand are selected.The results show that the desorption of Mn(II)is irreversible,and the adsorption of Mn(II)is irreversible.It is found that there is a clear hysteresis in the desorption of Mn(II),which is closely related to the slow release of Mn(II).The adsorption characteristics of the fine sandstone cylinder block are explored,and the corresponding relationship between the adsorption quantity of the unit area and the unit adsorption capacity of the sample is obtained.The purification model of the underground reservoir water is established according to the geological conditions of the Meihua well coal mine,and the purification capacity of the reservoir to Mn(II)is calculated.