refining n : the process of removing impurities (as from oil or metals or sugar etc.) [syn: refinement, purification]
- present participle of refine
- the process of purification of a substance
- German: Raffination
Refining is the process of purification of a substance. The term is usually used of a natural resource that is almost in a usable form, but which is more useful in its pure form. For instance, most types of natural petroleum will burn straight from the ground, but it will burn poorly and quickly clog an engine with residues and byproducts. The term is broad, and may include more drastic transformations, such as the reduction of ore to metal (for which see Refining (metallurgy)).
The refining of liquids is often accomplished by distillation or fractionation. Gases can be refined in this way as well, by being cooled and/or compressed until they liquefy. Gases and liquids can also be refined by extraction with a selective solvent that dissolves away either the substance of interest, or the unwanted impurities.
Many solids can be refined by growing crystals in a solution of the impure material; the regular structure of the crystal tends to favor the desired material and exclude other kinds of particles.
Chemical reactions are often used to remove impurities of particular types.
The use of silicon and other semiconductors in electronics is highly dependent on precise control of impurities, and a number of special techniques have been developed, such as zone refining.
Types of materials that are usually refined:
refining in Danish: Raffinering
refining in German: Raffination
refining in Spanish: Refinación
refining in Persian: پالایش
refining in French: Raffinage
refining in Icelandic: Hreinsun
refining in Italian: Raffinazione
refining in Georgian: აფინაჟი
refining in Japanese: 精錬
refining in Dutch: Raffinage
refining in Norwegian: Foredling
refining in Polish: Rafinacja
refining in Russian: Аффинаж
refining in Serbo-Croatian: Rafiniranje
refining in Finnish: Raffinointi
refining in Swedish: Raffinering
refining in Chinese: 精炼