Although both beryllium and its compounds display high toxicity, little attention has been focused on the removal of beryllium from wastewaters. In this research, magnetically modified biochar obtained from poor-quality wheat with two distinct Fe_xO_y contents was studied as a sorbent for the elimination of beryllium from an aqueous solution. The determined elimination efficiency was higher than 80% in both prepared composites, and the presence of Fe_xO_y did not affect the sorption properties. The experimental q_max values were determined to be 1.44 mg/g for original biochar and biochar with lower content of iron and 1.45 mg/g for the biochar with higher iron content. The optimum pH values favorable for sorption were determined to be 6. After the sorption procedure, the sorbent was still magnetically active enough to be removed from the solution by a magnet. Using magnetically modified sorbents proved to be an easy to apply, low-cost, and effective technique.

The anatase (TiO₂) particles magnetically modified by iron oxides and prepared by an innovating technological procedure are studied from the viewpoint of microstructure and a complex analysis of magnetic behaviour at room and elevated temperatures. Scanning electron microscopy observations have yielded variable shapes of particles in the composite powder whereas the iron oxide particles of diameter bellow 1 μm were detected on the surface of the TiO₂. The dominant magnetite (Fe₃O₄) accompanied by a small amount of maghemite (γ-Fe₂O₃) and/or hematite (α- Fe₂O₃) were analysed by X-ray powder diffraction. A relatively high saturation magnetization (3.38 Am²/kg), negative dipolar interactions, and the low values of reversible and irreversible part of magnetic susceptibility were found out from magnetic measurements at room temperature. During a thermomagnetic treatment the composite sample has been going through a few magnetic phase transitions and transforms into a fully paramagnetic state around 850 K. After its cooling to the room temperature an undesirable magnetic hardening of the sample has occurred.

A biomonitoring technique never before used in the Czech Republic was used to test its validity and applicability in the region of Ostrava that is eminently affected by industry. Transplants of two moss species Hylocomium splendens and Pleurozium schreberi were exposed to atmospheric pollution using the technique of an “irrigated moss bag” placed at a height of both 1 m and 2 m above ground. The samples were then analysed for concentration levels of trace elements Al, As, Cd, Cr, Cu, Fe, Hg, Pb, V and Zn. The patterns of bioaccumulation in general show that Hylocomium splendens is more suitable for monitoring purposes and that 2 m height above ground of transplants should be preferred.

Biochar produced from fermentation residue of maize hybrid was used in untreated form as a sorbent for the removal of Cd(II), Pb(II) and Zn(II) from aqueous solution. The capability of biochar to immobilized ions was investigated by leaching test. Equilibrium between biochar sample and studied elements in solution was reached at a contact time 30 min for Zn(II) and 90 min for Pb(II) and Cd(II). The experimental data were described by pseudofirst-order and pseudo-second-order kinetic model, two- and three-parameter isotherms in non-linear form. The maximum sorption capacity achieved was 30.07 mg·g⁻¹ in the case of Cd(II) ions, 99.44 mg·g⁻¹ in the case of Pb(II) and 40.18 in the case of Zn(II). Biochar developed for this study is comparable to conventional biochar, low cost, non-toxic and experimental results show that is a suitable and efficient sorbent for Cd(II), Pb(II) and Zn(II) removal from aqueous solutions.