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Isotope separation is the process of concentrating specific isotopes of a chemical element by removing other isotopes. The use of the nuclides produced is varied. The largest variety is used in research (e.g. in chemistry where atoms of "marker" nuclide are used to figure out reaction mechanisms).
The most notable examples of mass-independent fractionation in nature are found in the isotopes of oxygen and sulfur.The first example was discovered by Robert N. Clayton, Toshiko Mayeda, and Lawrence Grossman in 1973, [2] in the oxygen isotopic composition of refractory calcium–aluminium-rich inclusions in the Allende meteorite.
Equilibrium isotope fractionation is the partial separation of isotopes between two or more substances in chemical equilibrium. Equilibrium fractionation is strongest at low temperatures, and (along with kinetic isotope effects) forms the basis of the most widely used isotopic paleothermometers (or climate proxies): D/H and 18 O/ 16 O records from ice cores, and 18 O/ 16 O records from calcium ...
All isotopes of a given element have the same number of protons in each atom. The term isotope is formed from the Greek roots isos (ἴσος "equal") and topos (τόπος "place"), meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table.
Isotope fractionation occurs during a phase transition, when the ratio of light to heavy isotopes in the involved molecules changes. When water vapor condenses (an equilibrium fractionation), the heavier water isotopes (18 O and 2 H) become enriched in the liquid phase while the lighter isotopes (16 O and 1 H) tend toward the vapor phase. [1]
Fractionation is a separation process in which a certain quantity of a mixture (of gasses, solids, liquids, enzymes, or isotopes, or a suspension) is divided during a phase transition, into a number of smaller quantities in which the composition varies according to a gradient.
Diagram of a gas centrifuge with countercurrent flow, used for separating isotopes of uranium. A gas centrifuge is a device that performs isotope separation of gases. A centrifuge relies on the principles of centrifugal force accelerating molecules so that particles of different masses are physically separated in a gradient along the radius of a rotating container.
The COLEX process (or COLEX separation) is a chemical method of isotopic separation of lithium-6 and lithium-7, based on the use of mercury. COLEX stands for column exchange. COLEX stands for column exchange.