Formation of nanoclusters in the transition of carbon dioxide to the supercritical state

• Дата: 2022
• Автори: Borts, B.V., Skoromnaya, S.F., Tkachenko, I.V., Tkachenko, V.I.
• Формат: Стаття
• Мова: English
• Опубліковано: Національний науковий центр «Харківський фізико-технічний інститут» НАН України 2022
• Назва видання: Вопросы атомной науки и техники
• Теми: Diagnostics and methods of researches
• Онлайн доступ: http://dspace.nbuv.gov.ua/handle/123456789/195666
• Назва журналу: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Цитувати: Formation of nanoclusters in the transition of carbon dioxide to the supercritical state / B.V. Borts, S.F. Skoromnaya, I.V. Tkachenko, V.I. Tkachenko // Problems of Atomic Science and Technology. — 2022. — № 4. — С. 157-163. — Бібліогр.: 29 назв. — англ.

Supercritical fluid extraction (SFE) with CO₂ is widely used to extract biological materials, metal complexes and their isotopes. Supercritical CO₂ (SC-CO₂) is an environmentally friendly, efficient, and affordable solvent. However, the change in the chemical and physical properties of CO₂ in the transition to the supercritical (SC) state has not been studied so far. The paper proposes to consider such a change as a result of the formation of elementary linear, flat or volumetric nanoclusters, from which large nanoclusters can also be formed. 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 is confirmed by absorption spectra in the IR range for wavelengths of 4.2…4.4 μm in sub- and SC-CO₂.