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Information × Registration Number 0220U000457, 0115U006853 , R & D reports Title State of organic ions and ionic associates on the surface and in the interlayer gaps of layer silicates as comprehensively studied various methods (adsorption from liquid and vapour phases, calorimetry, X-ray analysis, quantum chemistry). popup.stage_title Head Mishchuk Natalia Oleksijivna, Registration Date 12-02-2020 Organization A.V Dumansky Institute of Colloid Chemistry and Water Chemistry popup.description2 Goal of research - to develop the concept of mutual interaction between the elements of modifying layers and the interaction of these elements with bound water. Research objects - adsorbents - natural and modified layer silicates; modifiers - cationic surface-active substances; adsorbates - water, anionic dyes, short-chain surfactants, humate. Methods of research - preparative, calorimetry, structural sorption, spectral, quantum chemical, molecular statistics. Equipment - spectrophotometer, high-sensitive calorimeter Tiana-Calve Ms-70, difractometer Bruker AXS D8, laboratory tensiometer, personal computer. Theoretical and practical results - the influence of inorganic and organic components of natural waters on the sorption of anionic surfactants on modified natural sorbents is studied. It is shown that the presence of insignificant concentrations of such surfactants in natural water (at the level of maximum permissible concentrations) leads to a significant increase in the adsorption of organic components on the sorbent, which violates the natural balance of the redistribution of important components of aquatic ecosystems. Ab initio calculations were used to study the complexation and decomplexation reactions of anionic and cationic surface substances in their state adsorbed on the surface anion of layered silicate and in an aqueous solution. It was shown that the hydrated complex "surface anion of the layered silicate: water: modifying cation" is unstable and does not play a significant role in the studied processes. At the same time, the energetic effect of the formation of a hydrated complex "modifying a cation: water: anionic surfactant" is significantly less than the effect of the formation of structures without binding water molecules. Such results determine the possible directions for creating selective complex adsorbents applicable in the environmental industry and healthcare. The use of an integrated approach involving sorption-analytical, calorimetric, and X-ray diffractometric methods of research to study the ion exchange of long chain cations on ion-substituted forms of layered silicates from premicellar aqueous solutions made it possible to show a number of significant features of the physicochemical behavior of this system that are essential for the use of such modified sorbents in adsorbents. It was shown that the selective adsorption of polar organic compounds on polar adsorbents is due to weak chemical interaction through hydrogen bonds with adsorbents and water molecules, which confirms the ability to predict the adsorption properties of the adsorbent based on information on the physicochemical properties of the adsorbate. The role of various oxidizing agents (oxygen, ozone, potassium permanganate, chlorine dioxide, sodium hypochlorite) in the demanganization of groundwater is analyzed. As the potassium permanganate is a precursor, and oxygen and ozone require the creation of a water treatment unit with intensive bubbling of the gases, the main attention was paid to the use of chlorine compounds, since they are widely used for disinfecting water at waterworks in Ukraine; in particular, it has been shown that they can be efficient in demanganation in a wide pH range. Novelty - for the first time the characteristic features of the behaviour of studied systems during the adsorption on the surface and interlayer gaps of layer silicates are determined. Efficiency of implementation - the advantages are revealed of the practical application of organomodified vermiculite for the improvement of water quality. Field of use - environment protection. Product Description popup.authors Іванова Зінаїда Григорівна Аксененко Євген Володимирович Доленко Світлана Олександрівна Крисенко Дмитро Анатолійович Міщук Наталія Олексіївна Трифонова Марина Юріївна popup.nrat_date 2020-04-02 Close