Příprava a charakterizace magneticky modifikovaných fylosilikátů

Abstract

The bachelor thesis is focused on the influence of the amount of iron in the form of magnetic oxides on the properties of prepared composites based on phyllosilicates. The materials prepared in this way have a potential use in removing pollutants from the environment. The advantage of the prepared composites is the simplicity of their separation after the adsorption process by applying an external magnetic field. To evaluate the effect of iron content on the resulting properties of composites, a series of samples of magnetically modified bentonite and montmorillonite differing from the initial iron content was prepared. The microwave-assisted precipitation procedure was used to prepare these composites. Various characterization methods have been used to verify the effect of total iron content in the form of iron oxides in composites. Among the analyzes performed, the total content of iron and iron oxide was determined, the surface of the composites was studied by scanning electron microscopy and the surface coverage of the composites with iron oxides was monitored. Furthermore, the composites were studied by X-ray diffraction analysis, the specific surface area was determined, the magnetic properties were measured and adsorption experiments were performed using cadmium ions. Experiments have shown that increasing the total content of iron oxides has a different effect on the magnetic properties of the composite prepared from montmorillonite and bentonite. When using higher contents of precursor of prepared iron oxides, both types of phyllosilicates intercalate ferrous and ferric ions into the intermediate layer of composites. Magnetic iron oxides mainly occupy the surface of phyllosilicates and thus significantly affect their adsorption capacity of cadmium ions.