Influence of the Sorption of Pollution Markers on the Physicochemical Properties of Sorbents

The collective influence of sorbed iron, manganese, sulfate, and nitrate ions—markers of water pollution from coal mines—on the physicochemical properties of the surface of AS and MS sorbents is studied by infrared (IR) spectroscopy, scanning electron microscopy, thermal analysis, and nitrogen porosimetry. The IR spectroscopic data for the relative content of oxygen groups at the sorbent surface after adsorption from the mixture correlate with the thermogravimetric results (thermal expansion coefficient, mass loss of the sample in different temperature ranges) and with nitrogen porosimetry. Changes in the proportions of Si–OH and Si–O bonds indicate restructuring of the hydrate groups and layer by layer sorption of marker ions. As a result, qualitative and quantitative changes in the proportions of pores are observed, as confirmed by porosimetry and the analysis of surface images from a scanning electron microscope.