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Information × Registration Number 0223U004871, 0122U000915 , R & D reports Title Development of a physical model and determination of optimal parameters of supercritical fluid extraction of metal complexes and their isotopes in carbon dioxide medium popup.stage_title Head Tkachenko Viktor I., Доктор фізико-математичних наук Registration Date 06-12-2023 Organization National Science Center "Kharkiv Institute of Physics and Technology" popup.description2  Supercritical fluid CO2 extraction (SFE-CO2) is widely used to extract biological materials, metal complexes and their isotopes. SFE-CO2 is an environmentally friendly, effective and affordable solvent. However, until now, the change in the chemical and physical properties of CO2 during the transition to the supercritical state has not been investigated. A physical model of the formation of nanoclusters during the transition of carbon dioxide to a supercritical state has been developed. As a result of the conducted research, it is proposed to consider such a change as the result of the formation of elementary linear, planar or three-dimensional nanoclusters. It is assumed that such elementary nanoclusters can form much larger nanoclusters. Based on the theory of repulsion of valence electron pairs, the geometry of the arrangement of atoms in elementary nanoclusters is described. The change in the chemical and physical properties of CO2 during the formation of nanoclusters is confirmed by absorption spectra in the IR range for wavelengths of 4.2...4.4 μm in pre- and supercritical CO2. The analysis of experimental and theoretical data shows that the reason for the large solubility of water under normal conditions and in the SC state is obviously solvate electrons, which are formed under the action of accelerated electrons in the normal state of water, or when it is in a supercritical state. Product Description popup.authors Bratchenko Mykhailo Tkachenko Ivan Tkachenko Viktor Khyzhnyak Sergiy popup.nrat_date 2023-12-06 Close