charcoal, substance obtained by partial burning or carbonization (destructive distillation distillation, process used to separate the substances composing a mixture. It involves a change of state, as of liquid to gas, and subsequent condensation . The process was probably first used in the production of intoxicating beverages.
..... Click the link for more information. ) of organic material. It is largely pure carbon carbon [Lat.,=charcoal], nonmetallic chemical element; symbol C; at. no. 6; at. wt. 12.011; m.p. about 3,550°C;; graphite sublimes about 3,375°C;; b.p. 4,827°C;; sp. gr. 1.8–2.1 (amorphous), 1.9–2.3 (graphite), 3.15–3.
..... Click the link for more information. . The entry of air during the carbonization process is controlled so that the organic material does not turn to ash, as in a conventional fire, but decomposes to form charcoal.

The most common variety of charcoal, wood charcoal, was formerly prepared by piling wood into stacks, covering it with earth or turf, and setting it on fire. In this process volatile compounds in the wood (e.g., water) pass off as vapors into the air, some of the carbon is consumed as fuel, and the rest of the carbon is converted into charcoal. In the modern method, wood is raised to a high temperature in an iron retort, and industrially important byproducts, e.g., methanol methanol, methyl alcohol, or wood alcohol, CH₃OH, a colorless, flammable liquid that is miscible with water in all proportions. Methanol is a monohydric alcohol . It melts at −97.
..... Click the link for more information. (wood alcohol or wood spirit), acetone acetone (ăs`ĭtōn), dimethyl ketone
..... Click the link for more information. , pyroligneous acid pyroligneous acid (pī'rəlĭg`nēəs)
..... Click the link for more information. , and acetic acid acetic acid (əsē`tĭk), CH₃CO₂
..... Click the link for more information. , are saved by condensing them to their liquid form. Air is not really needed in the carbonization process, and advanced methods of charcoal production do not allow air to enter the kiln. This results in a higher yield, since no wood is burned with the air, and quality is improved. Charcoal is also obtained from substances other than wood such as nut shells and bark; that obtained from bones is called bone black, animal black, or animal charcoal.

Charcoal yields a larger amount of heat in proportion to its volume than is obtained from a corresponding quantity of wood and has the further advantage of being smokeless. The greatest amount is used as a fuel. Charcoal is often used in blacksmithing, for cooking, and for other industrial applications. One of the most important applications of wood charcoal is as a component of gunpowder gunpowder, explosive mixture; its most common formula, called "black powder," is a combination of saltpeter, sulfur, and carbon in the form of charcoal. Historically, the relative amounts of the components have varied.
..... Click the link for more information. . It is also used as a reducing agent in metallurgical operations, but this application was diminished by the introduction of coke coke, substance obtained by the destructive distillation of bituminous coal . Coke bears the same relation to coal as does charcoal to wood. A hard, gray, massive, porous fuel, coke is the solid residue remaining after bituminous coal is heated to a high temperature
..... Click the link for more information. . A limited quantity is made up into the form of drawing crayon. Bamboo charcoal is the principal ingredient in sumi-e, a form of Japanese ink painting that uses only black ink in various concentrations.

Because of its porous structure, finely divided charcoal is a highly efficient agent for filtering the adsorption of gases and of solids from solution. It is used in sugar refining, in water purification, in the purification of factory air, and in gas masks. Wood charcoal can remove coloring agents from solutions, but this is accomplished more efficiently by animal charcoal. By special heating or chemical processes the adsorptive property can be greatly increased; charcoal so treated is known as activated charcoal.

charcoal

Impure form of carbon, obtained as a residue when material containing carbon is partially burned or heated with limited access to air. Coke, carbon black, and soot are forms of charcoal; other forms are named for their source material, such as wood, blood, or bone. Largely replaced by coke in blast furnaces and by natural gas as a raw material, charcoal is still used to make black gunpowder and in case-hardening metals. Activated charcoal is a finely powdered or highly porous form whose surface area is hundreds or thousands of square meters per gram. It has many uses as an adsorbent (see adsorption), including for poison treatment, and as a catalyst or catalyst carrier.

charcoal

1. a black amorphous form of carbon made by heating wood or other organic matter in the absence of air: used as a fuel, in smelting metal ores, in explosives, and as an absorbent

2. a stick or pencil of this for drawing

3. a drawing done in charcoal

charcoal (redirected from charcoal-grey)

charcoal

charcoal
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