Volume 40, Nº 5 (2018)

Using sodium dodecylbenzenesulfonate the article showed high efficiency of photocatalytic system H₂O₂/TiO₂/UV for deep destruction (~ 90% in terms of TOC) of anionic SAS in a aqueousmedium (C₀ = 50 mg/dm³, pH₀ 5.9) in a reactor containing wide–porous ceramic block with immobilized TiO₂ on its surface. The TiO₂ film for a long time preserved a stable photocatalytic activity

Results of test coagulation of highly colored Dnieper water by a composite coagulant (CC) obtained by acidizing red mud are presented. It is shown that CC ensures a decrease of basic quality indexes of Dnieper water by 10–20% more effectively than aluminum sulfate (AS). In this case water is contaminated with iron compounds. To lower its concentration it is proposed additionally treat water with ozone, chlorine dioxide or sodium hypochlorite being fed to mixers or flocculation chambers. An alternative way is the use of composition mixture in the form of addition CC to AS in the ratio 1/2–1/1 (in terms of Fe₂O₃/Al₂O₃).

The possibility of using magnetic sorbents for the removal of Co(II), Ni(II) and Cd(II) from water media is shown. It was established that magnetite is more effective compared with magnetic potassium–zinc hexacyanoferrate(II). The pH (> 4) and the dose of sorbents were defined for obtaining maximum possible degree of removing ions of specified metals from water media.

Homogeneous liquid-liquid microextraction via flotation assistance method was developed for extraction of lead in water. A mixture of extraction solvent (1-decanol) and disperser solvent (acetone) containing dithizone as chelating agent is injected into microextraction cell. Then an aqueous sample is injected into microextraction cell until the mixture of solvent forms initial state a homogeneous solution and then forms an emulsion consisting of fine droplets of the extraction solvent, disperser solvent and water. Using air flotation, the extraction solvent is transferred to the surface of the mixture and is collected by means of a micro-syringe. Then 25 μL of the collected organic solvent is diluted with 800 μL decanol and is analyzed with spectrophotometer in 520 nm wavelength. Also, the thermochemistry of complexation reactions was investigated at PM6 and B3LYP/6-31G* computational level.

Isomers of benzoperene were studied. Calculated values of hydrophobicity of their molecules were analyzed. The search for optimal conditions of extraction removal from atmospheric water of isomers of benzopyrene and chromatographic separation of benzo(e)pyrene and benzo(a)pyrene in atmospheric water (snow) was made. The concentration of benzo(e)pyrene and benzo(a)pyrene in atmospheric water (snow) polluted by polycyclic aromatic hydrocarbons (benzo(a)anthracene, benzo(b)fluoranthene, chrysene) was determined.

Organic wastewater concentration has been investigated by the method of sorption combined with microfiltration. The introduction of ground solid wastes from the facilities of agroindustrial complex makes it possible to enhance the efficiency of membrane concentration. The subsequent treatment under conditions of supercritical water oxidation results in obtaining the water with admissible amount of organic pollutants.

The seasonal variation of the content of phosphates dissolved in the Volga water is investigated on the basis of multi-year observations under conditions of anthropogenic eutrophication of reservoirs. It has been established that the amplitude of seasonal changes of phosphates depends on the intensity of algal nuisance. In low-water years, the concentration of phosphates and chlorophyll a change in antiphase.