Fractional freezing is a process used in process engineering and chemistry to separate substances with different melting points. It can be done by partial melting of a solid, for example in zone refining of silicon or metals, or by partial crystallization of a liquid, as in freeze distillation, also called normal freezing or progressive freezing. The initial sample is thus fractionated (separated into fractions).
Partial crystallization can also be achieved by adding a dilute solvent to the mixture, and cooling and concentrating the mixture by evaporating the solvent, a process called solution crystallization. Fractional freezing is generally used to produce ultra-pure solids, or to concentrate heat-sensitive liquids.
Freeze distillation is a misnomer, because it is not distillation but rather a process of enriching a solution by partially freezing it and removing frozen material that is poorer in the dissolved material than is the liquid portion left behind. Such enrichment parallels enrichment by true distillation, where the evaporated and re-condensed portion is richer than the liquid portion left behind.
Ethanol and liquid water are completely miscible, but ethanol is practically insoluble in water ice. That means almost pure water ice can be precipitated from a lean ethanol-water mixture by cooling it sufficiently. The precipitation of water ice from the mixture enriches ethanol in the remaining liquid phase. The two phases can then be separated by filtration or decanting. The temperature at which water ice starts to precipitate depends on the ethanol concentration. Consequently, at a given temperature and ethanol concentration, the freezing process will reach an equilibrium at a specific ratio of water ice and enriched ethanol solution with a specific ethanol concentration. The temperatures and mixing ratios of these phase equilibria can be read from the phase diagram of ethanol and water. The maximum enrichment of ethanol in the liquid phase is reached at the eutectic point of ethanol and water, approximately 92.
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Fractional freezing is a process used in process engineering and chemistry to separate substances with different melting points. It can be done by partial melting of a solid, for example in zone refining of silicon or metals, or by partial crystallization of a liquid, as in freeze distillation, also called normal freezing or progressive freezing. The initial sample is thus fractionated (separated into fractions).
Acetic acid əˈsiːtᵻk, systematically named ethanoic acid ˌɛθəˈnoʊᵻk, is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component of vinegar apart from water and other trace elements. Acetic acid is the second simplest carboxylic acid (after formic acid). It is an important chemical reagent and industrial chemical, used primarily in the production of cellulose acetate for photographic film, polyvinyl acetate for wood glue, and synthetic fibres and fabrics.
Liquor (ˈlɪkər ) is an alcoholic drink produced by the distillation of grains, fruits, vegetables, or sugar that have already gone through alcoholic fermentation. Other terms for liquor include: spirit, distilled beverage, spirituous liquor or hard liquor. The distillation process concentrates the liquid to increase its alcohol by volume. As liquors contain significantly more alcohol (ethanol) than other alcoholic drinks, they are considered "harder.
Explores binary systems, phase diagrams, and elastic properties in materials science, emphasizing phase equilibria and material behavior under deformation.