Charcoal
Encyclopedia

Charcoal is the dark grey residue consisting of carbon
Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...

, and any remaining ash
Ash
- Products of fire, incineration or combustion :The solid remains of fires, such as:* Ash , the compounds that remain after a scientific sample is burned; commonly reported as a percentage on pet food labels...

, obtained by removing water and other volatile constituents from animal
Animal
Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...

 and vegetation
Vegetation
Vegetation is a general term for the plant life of a region; it refers to the ground cover provided by plants. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characteristics. It is broader...

 substances. Charcoal is usually produced by slow pyrolysis
Pyrolysis
Pyrolysis is a thermochemical decomposition of organic material at elevated temperatures without the participation of oxygen. It involves the simultaneous change of chemical composition and physical phase, and is irreversible...

, the heating of wood
Wood
Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...

 or other substances in the absence of oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...

 (see pyrolysis
Pyrolysis
Pyrolysis is a thermochemical decomposition of organic material at elevated temperatures without the participation of oxygen. It involves the simultaneous change of chemical composition and physical phase, and is irreversible...

, char
Charring
Charring is a chemical process of incomplete combustion of certain solids when subjected to high heat. The resulting residue matter is called Char. By the action of heat, charring removes hydrogen and oxygen from the solid, so that the remaining char is composed primarily of carbon...

 and biochar
Biochar
Biochar or terra preta is charcoal created by pyrolysis of biomass. Biochar is under investigation as an approach to carbon sequestration via bio-energy with carbon capture and storage. Biochar thus has the potential to help mitigate climate change, via carbon sequestration...

). It is usually an impure form of carbon
Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...

 as it contains ash; however, sugar
Sugar
Sugar is a class of edible crystalline carbohydrates, mainly sucrose, lactose, and fructose, characterized by a sweet flavor.Sucrose in its refined form primarily comes from sugar cane and sugar beet...

 charcoal
Charcoal
Charcoal is the dark grey residue consisting of carbon, and any remaining ash, obtained by removing water and other volatile constituents from animal and vegetation substances. Charcoal is usually produced by slow pyrolysis, the heating of wood or other substances in the absence of oxygen...

 is among the purest forms of carbon
Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...

 readily available, particularly if it is not made by heating but by dehydrating with sulphuric acid to minimise introducing new impurities, as impurities can be removed from the sugar
Sugar
Sugar is a class of edible crystalline carbohydrates, mainly sucrose, lactose, and fructose, characterized by a sweet flavor.Sucrose in its refined form primarily comes from sugar cane and sugar beet...

 in advance. The resulting soft, brittle, lightweight, black, porous material resembles coal
Coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...

.

History

Historically, production of wood charcoal in districts where there is an abundance of wood dates back to a very ancient period, and generally consists of piling billets of wood on their ends so as to form a conical pile, openings being left at the bottom to admit air, with a central shaft to serve as a flue
Flue
A flue is a duct, pipe, or chimney for conveying exhaust gases from a fireplace, furnace, water heater, boiler, or generator to the outdoors. In the United States, they are also known as vents and for boilers as breeching for water heaters and modern furnaces...

. The whole pile is covered with turf or moistened clay
Clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...

. The firing is begun at the bottom of the flue, and gradually spreads outwards and upwards. The success of the operation depends upon the rate of the combustion
Combustion
Combustion or burning is the sequence of exothermic chemical reactions between a fuel and an oxidant accompanied by the production of heat and conversion of chemical species. The release of heat can result in the production of light in the form of either glowing or a flame...

. Under average conditions, 100 parts of wood yield about 60 parts by volume
Volume
Volume is the quantity of three-dimensional space enclosed by some closed boundary, for example, the space that a substance or shape occupies or contains....

, or 25 parts by weight
Weight
In science and engineering, the weight of an object is the force on the object due to gravity. Its magnitude , often denoted by an italic letter W, is the product of the mass m of the object and the magnitude of the local gravitational acceleration g; thus:...

, of charcoal; small scale production on the spot often yields only about 50%, large scale was efficient to about 90% even by the seventeenth century. The operation is so delicate that it was generally left to colliers (professional charcoal burners).

The massive production of charcoal (at its height employing hundreds of thousands, mainly in Alpine and neighbouring forests) was a major cause of deforestation
Deforestation
Deforestation is the removal of a forest or stand of trees where the land is thereafter converted to a nonforest use. Examples of deforestation include conversion of forestland to farms, ranches, or urban use....

, especially in Central Europe
Central Europe
Central Europe or alternatively Middle Europe is a region of the European continent lying between the variously defined areas of Eastern and Western Europe...

. In England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

, many woods were managed as coppices, which were cut and regrew cyclically, so that a steady supply of charcoal would be available (in principle) forever; complaints (as early as the Stuart period) about shortages may relate to the results of temporary over-exploitation or the impossibility of increasing production to match growing demand. The increasing scarcity of easily harvested wood was a major factor for the switch to the fossil fuel
Fossil fuel
Fossil fuels are fuels formed by natural processes such as anaerobic decomposition of buried dead organisms. The age of the organisms and their resulting fossil fuels is typically millions of years, and sometimes exceeds 650 million years...

 equivalents, mainly coal
Coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...

 and brown coal for industrial use.

The use of charcoal as a smelting fuel has been experiencing a resurgence in South America following Brazilian law changes in 2010 to reduce carbon emissions as part of President Lula da Silva's commitment to make a "green steel".

The modern process of carbonizing wood, either in small pieces or as sawdust
Sawdust
Sawdust is a by-product of cutting lumber with a saw, composed of fine particles of wood. It can present a hazard in manufacturing industries, especially in terms of its flammability....

 in cast iron
Cast iron
Cast iron is derived from pig iron, and while it usually refers to gray iron, it also identifies a large group of ferrous alloys which solidify with a eutectic. The color of a fractured surface can be used to identify an alloy. White cast iron is named after its white surface when fractured, due...

 retort
Retort
In a chemistry laboratory, a retort is a glassware device used for distillation or dry distillation of substances. It consists of a spherical vessel with a long downward-pointing neck. The liquid to be distilled is placed in the vessel and heated...

s, is extensively practiced where wood is scarce, and also for the recovery of valuable byproducts (wood spirit, pyroligneous acid
Pyroligneous acid
Pyroligneous acid, also called wood vinegar, is a dark liquid produced through the natural act of carbonization, which occurs when wood is heated in an airless container during charcoal production.-Chemical components:...

, wood tar
Tar
Tar is modified pitch produced primarily from the wood and roots of pine by destructive distillation under pyrolysis. Production and trade in tar was a major contributor in the economies of Northern Europe and Colonial America. Its main use was in preserving wooden vessels against rot. The largest...

), which the process permits. The question of the temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...

 of the carbonization
Carbonization
Carbonization or carbonisation is the term for the conversion of an organic substance into carbon or a carbon-containing residue through pyrolysis or destructive distillation. It is often used in organic chemistry with reference to the generation of coal gas and coal tar from raw coal...

 is important; according to J. Percy, wood becomes brown at 220 °C (428 °F), a deep brown-black after some time at 280 °C (536 °F), and an easily powdered mass at 310 °C (590 °F). Charcoal made at 300°C (572 °F) is brown, soft and friable, and readily inflames at 380 °C (716 °F); made at higher temperatures it is hard and brittle, and does not fire until heated to about 700 °C (1,292 °F).

In Finland
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...

 and Scandinavia
Scandinavia
Scandinavia is a cultural, historical and ethno-linguistic region in northern Europe that includes the three kingdoms of Denmark, Norway and Sweden, characterized by their common ethno-cultural heritage and language. Modern Norway and Sweden proper are situated on the Scandinavian Peninsula,...

, the charcoal was considered the by-product of wood tar
Tar
Tar is modified pitch produced primarily from the wood and roots of pine by destructive distillation under pyrolysis. Production and trade in tar was a major contributor in the economies of Northern Europe and Colonial America. Its main use was in preserving wooden vessels against rot. The largest...

 production. The best tar came from pine
Pine
Pines are trees in the genus Pinus ,in the family Pinaceae. They make up the monotypic subfamily Pinoideae. There are about 115 species of pine, although different authorities accept between 105 and 125 species.-Etymology:...

, thus pinewoods were cut down for tar pyrolysis
Pyrolysis
Pyrolysis is a thermochemical decomposition of organic material at elevated temperatures without the participation of oxygen. It involves the simultaneous change of chemical composition and physical phase, and is irreversible...

. The residual charcoal was widely used as substitute for metallurgical
Metallurgy
Metallurgy is a domain of materials science that studies the physical and chemical behavior of metallic elements, their intermetallic compounds, and their mixtures, which are called alloys. It is also the technology of metals: the way in which science is applied to their practical use...

 coke
Coke (fuel)
Coke is the solid carbonaceous material derived from destructive distillation of low-ash, low-sulfur bituminous coal. Cokes from coal are grey, hard, and porous. While coke can be formed naturally, the commonly used form is man-made.- History :...

 in blast furnace
Blast furnace
A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally iron.In a blast furnace, fuel and ore and flux are continuously supplied through the top of the furnace, while air is blown into the bottom of the chamber, so that the chemical reactions...

s for smelting
Smelting
Smelting is a form of extractive metallurgy; its main use is to produce a metal from its ore. This includes iron extraction from iron ore, and copper extraction and other base metals from their ores...

. Tar production led to rapid deforestation
Deforestation
Deforestation is the removal of a forest or stand of trees where the land is thereafter converted to a nonforest use. Examples of deforestation include conversion of forestland to farms, ranches, or urban use....

: it has been estimated all Finnish forests are younger than 300 years. The end of tar production in the end of the 19th century meant also rapid re-forestation.

The charcoal briquette
Briquette
A briquette is a block of flammable matter used as fuel to start and maintain a fire. Common types of briquettes are charcoal briquettes and biomass briquettes.-Constituents of charcoal briquettes:...

 was first invented and patented by Ellsworth B. A. Zwoyer of Pennsylvania in 1897 and was produced by the Zwoyer Fuel Company. The process was further popularized by Henry Ford
Henry Ford
Henry Ford was an American industrialist, the founder of the Ford Motor Company, and sponsor of the development of the assembly line technique of mass production. His introduction of the Model T automobile revolutionized transportation and American industry...

, who used wood and sawdust byproducts from automobile fabrication as a feedstock. Ford Charcoal went on to become the Kingsford Company
Kingsford (charcoal)
Kingsford is a brand of charcoal used for grilling, along with related products. The brand is owned by The Clorox Company.The Kingsford Company was formed by Henry Ford and E.G. Kingsford during the early 1920s. Charcoal was developed from Ford Motor Company's factory waste wood scrap. The...

.

Production methods

Charcoal has been made by various methods. The traditional method in Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

 used a clamp
Storage clamp
A storage clamp is used in the agricultural industry for temporary storage of root crops such as potato, turnip, rutabaga, mangelwurzel, sugar beet etc....

. This is essentially a pile of wooden logs (e.g. seasoned oak) leaning against a chimney (logs are placed in a circle). The chimney consists of 4 wooden stakes held up by some rope. The logs are completely covered with soil and straw allowing no air to enter. It has to be lit by introducing some burning fuel into the chimney; the logs burn very slowly (cold fire) and transform into charcoal in a period of 5 days' burning. If the soil covering gets torn (cracked) by the fire, additional soil is placed on the cracks. Once the burn is complete, the chimney is plugged to prevent air from entering.

Modern methods use a sealed metal container, as this does not have to be watched lest fire break through the covering. However on site attendance is required. This is often carried out by the last forestry workers to live in working woodland in the western world. There has been a resurgence of this particularly in the UK. A good example of this is Bulworthy Project where charcoal production supports an experiment in low-impact living and nature conservation.

The last section of the film Le Quattro Volte (2010) gives a good and long, if poetic, documentation of the traditional method of making charcoal.

Types

Commercial charcoal is found in either lump, briquette
Briquette
A briquette is a block of flammable matter used as fuel to start and maintain a fire. Common types of briquettes are charcoal briquettes and biomass briquettes.-Constituents of charcoal briquettes:...

, or extruded forms:
  • Lump charcoal is made directly from hardwood
    Hardwood
    Hardwood is wood from angiosperm trees . It may also be used for those trees themselves: these are usually broad-leaved; in temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen.Hardwood contrasts with softwood...

     material and usually produces far less ash than briquettes.

  • Briquette
    Briquette
    A briquette is a block of flammable matter used as fuel to start and maintain a fire. Common types of briquettes are charcoal briquettes and biomass briquettes.-Constituents of charcoal briquettes:...

    s
    are made by compressing charcoal, typically made from sawdust and other wood by-products, with a binder and other additives. The binder is usually starch
    Starch
    Starch or amylum is a carbohydrate consisting of a large number of glucose units joined together by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store...

    . Some briquettes may also include brown coal (heat source), mineral carbon (heat source), borax
    Borax
    Borax, also known as sodium borate, sodium tetraborate, or disodium tetraborate, is an important boron compound, a mineral, and a salt of boric acid. It is usually a white powder consisting of soft colorless crystals that dissolve easily in water.Borax has a wide variety of uses...

    , sodium nitrate
    Sodium nitrate
    Sodium nitrate is the chemical compound with the formula NaNO3. This salt, also known as Chile saltpeter or Peru saltpeter to distinguish it from ordinary saltpeter, potassium nitrate, is a white solid which is very soluble in water...

     (ignition aid), limestone
    Limestone
    Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

     (ash-whitening agent), raw sawdust
    Sawdust
    Sawdust is a by-product of cutting lumber with a saw, composed of fine particles of wood. It can present a hazard in manufacturing industries, especially in terms of its flammability....

     (ignition aid), and other additives like paraffin
    Paraffin
    In chemistry, paraffin is a term that can be used synonymously with "alkane", indicating hydrocarbons with the general formula CnH2n+2. Paraffin wax refers to a mixture of alkanes that falls within the 20 ≤ n ≤ 40 range; they are found in the solid state at room temperature and begin to enter the...

     or petroleum solvent
    Hydrocarbon
    In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons from which one hydrogen atom has been removed are functional groups, called hydrocarbyls....

    s to aid in ignition.
  • Extruded charcoal is made by extruding either raw ground wood or carbonized wood into logs without the use of a binder. The heat and pressure of the extruding process hold the charcoal together. If the extrusion is made from raw wood material, the extruded logs
    Timber
    Timber may refer to:* Timber, a term common in the United Kingdom and Australia for wood materials * Timber, Oregon, an unincorporated community in the U.S...

     are then subsequently carbonized.

  • Japanese charcoal removes pyroligneous acid
    Pyroligneous acid
    Pyroligneous acid, also called wood vinegar, is a dark liquid produced through the natural act of carbonization, which occurs when wood is heated in an airless container during charcoal production.-Chemical components:...

     during the charcoal making. Therefore when burning, there are almost no stimulating smells or smoke. The charcoal of Japan is classified into three kinds.
    • White charcoal (Binchōtan
      Binchotan
      is a mascot character, created by Japanese manga artist and produced by game goods company Alchemist.The name is a play on words: is a kind of charcoal, which is mainly used for cooking. However, -tan is a suffix created by the mispronunciation of -chan...

      )
    • Black charcoal
    • Ogatan, Black charcoal that is made from hardened sawdust. Used in the Izakaya
      Izakaya
      An is a type of Japanese drinking establishment which also serves food to accompany the drinks. They are popular, casual places for after-work drinking.-Name:...

       or Yakiniku
      Yakiniku
      Yakiniku , meaning "grilled meat", is a Japanese term which, in its broadest sense, refers to grilled meat dishes. The present style of yakiniku restaurants are derived from the Korean restaurants in Osaka and Tokyo which were opened around 1945....

       restaurant.


The characteristics of charcoal products (lump, briquette
Briquette
A briquette is a block of flammable matter used as fuel to start and maintain a fire. Common types of briquettes are charcoal briquettes and biomass briquettes.-Constituents of charcoal briquettes:...

, or extruded forms) vary widely from product to product. Thus it is a common misconception to stereotype any kind of charcoal, saying which burns hotter, etc.
  • Bamboo charcoal
    Bamboo charcoal
    Bamboo charcoal is made up of pieces of bamboo, which are taken from plants five years or older and burned inside an oven at temperatures over 1000° C. It not only provides a new way to utilize bamboo, but also benefits environmental protection by reducing pollutant residue...

  • Activated carbon
    Activated carbon
    Activated carbon, also called activated charcoal, activated coal or carbo activatus, is a form of carbon that has been processed to make it extremely porous and thus to have a very large surface area available for adsorption or chemical reactions.The word activated in the name is sometimes replaced...


Uses

Charcoal has been used since the earliest times for a range of purposes including art and medicine, but by far its most important use has been as a metallurgical fuel. Charcoal is the traditional fuel of a blacksmith's forge and other applications where an intense heat is wanted. Charcoal was also used historically as a source of carbon black
Carbon black
Carbon black is a material produced by the incomplete combustion of heavy petroleum products such as FCC tar, coal tar, ethylene cracking tar, and a small amount from vegetable oil. Carbon black is a form of amorphous carbon that has a high surface-area-to-volume ratio, although its...

 by grinding it up. In this form charcoal was important to early chemists and was a constituent of formulas for mixtures such as gunpowder
Gunpowder
Gunpowder, also known since in the late 19th century as black powder, was the first chemical explosive and the only one known until the mid 1800s. It is a mixture of sulfur, charcoal, and potassium nitrate - with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer...

. Due to its high surface area
Surface area
Surface area is the measure of how much exposed area a solid object has, expressed in square units. Mathematical description of the surface area is considerably more involved than the definition of arc length of a curve. For polyhedra the surface area is the sum of the areas of its faces...

 charcoal can be used as a filter, as a catalyst
Carbocatalysis
Carbocatalysis is a form of catalysis that uses heterogeneous carbon materials for the transformation or synthesis of organic or inorganic substrates. The catalysts are characterized by their high surface areas, surface functionality, and large, aromatic basal planes...

 or as an absorbent.

Metallurgical fuel

Charcoal burns at intense temperatures, up to 2700 degrees Celsius. By comparison the melting point of iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

 is approximately 1200 to 1550 degrees Celsius. Due to its porosity it is sensitive to the flow of air and the heat generated can be moderated by controlling the air flow to the fire. For this reason charcoal is an ideal fuel for a forge and is still widely used by blacksmiths. Charcoal is also an excellent reducing fuel for the production of iron and has been used that way since Roman times. In the 16th century England had to pass laws to prevent the country from becoming completely denuded of trees due to production of iron. In the 19th century charcoal was largely replaced by coke
Coke (fuel)
Coke is the solid carbonaceous material derived from destructive distillation of low-ash, low-sulfur bituminous coal. Cokes from coal are grey, hard, and porous. While coke can be formed naturally, the commonly used form is man-made.- History :...

, baked coal, in steel making due to cost. Charcoal is far superior fuel to coke, however, because it burns hotter and has no sulfur. Until World War II charcoal was still being used in Sweden to make ultra high-quality steel.

Cooking fuel

Prior to the industrial revolution charcoal was occasionally used as a cooking fuel. Modern "charcoal briquette
Briquette
A briquette is a block of flammable matter used as fuel to start and maintain a fire. Common types of briquettes are charcoal briquettes and biomass briquettes.-Constituents of charcoal briquettes:...

s", widely used for outdoor grilling and barbecue
Barbecue
Barbecue or barbeque , used chiefly in the United States, Canada, the United Kingdom, New Zealand and Australia is a method and apparatus for cooking meat, poultry and occasionally fish with the heat and hot smoke of a fire, smoking wood, or hot coals of...

s in backyards and on camping
Camping
Camping is an outdoor recreational activity. The participants leave urban areas, their home region, or civilization and enjoy nature while spending one or several nights outdoors, usually at a campsite. Camping may involve the use of a tent, caravan, motorhome, cabin, a primitive structure, or no...

 trips, imitate this use, but are not actually charcoal. They are usually compacted mixtures of coal
Coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...

 or coke
Coke (fuel)
Coke is the solid carbonaceous material derived from destructive distillation of low-ash, low-sulfur bituminous coal. Cokes from coal are grey, hard, and porous. While coke can be formed naturally, the commonly used form is man-made.- History :...

 and various binders.

Industrial fuel

Historically, charcoal was used in great quantities for smelting iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

 in bloomeries
Bloomery
A bloomery is a type of furnace once widely used for smelting iron from its oxides. The bloomery was the earliest form of smelter capable of smelting iron. A bloomery's product is a porous mass of iron and slag called a bloom. This mix of slag and iron in the bloom is termed sponge iron, which...

 and later blast furnace
Blast furnace
A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally iron.In a blast furnace, fuel and ore and flux are continuously supplied through the top of the furnace, while air is blown into the bottom of the chamber, so that the chemical reactions...

s and finery forge
Finery forge
Iron tapped from the blast furnace is pig iron, and contains significant amounts of carbon and silicon. To produce malleable wrought iron, it needs to undergo a further process. In the early modern period, this was carried out in a finery forge....

s. This use was replaced by coke
Coke (fuel)
Coke is the solid carbonaceous material derived from destructive distillation of low-ash, low-sulfur bituminous coal. Cokes from coal are grey, hard, and porous. While coke can be formed naturally, the commonly used form is man-made.- History :...

 during the Industrial Revolution
Industrial Revolution
The Industrial Revolution was a period from the 18th to the 19th century where major changes in agriculture, manufacturing, mining, transportation, and technology had a profound effect on the social, economic and cultural conditions of the times...

. For this purpose, charcoal in England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 was measured in dozens (or loads) consisting of 12 sacks or shem
Shem
Shem was one of the sons of Noah in the Hebrew Bible as well as in Islamic literature. He is most popularly regarded as the eldest son, though some traditions regard him as the second son. Genesis 10:21 refers to relative ages of Shem and his brother Japheth, but with sufficient ambiguity in each...

s or seams, each of 8 bushel
Bushel
A bushel is an imperial and U.S. customary unit of dry volume, equivalent in each of these systems to 4 pecks or 8 gallons. It is used for volumes of dry commodities , most often in agriculture...

s.

Automotive fuel

In times of scarce petroleum, automobiles and even buses have been converted to burn wood gas
Wood gas
Wood gas is a syngas fuel which can be used as a fuel for furnaces, stoves and vehicles in place of petrol, diesel or other fuels. During the production process biomass or other carbon-containing materials is gasified within the oxygen-limited environment of a wood gas generator to produce hydrogen...

 (a gas mixture consisting primarily of diluting atmospheric nitrogen
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...

, but also containing combustible gasses, mostly carbon monoxide
Carbon monoxide
Carbon monoxide , also called carbonous oxide, is a colorless, odorless, and tasteless gas that is slightly lighter than air. It is highly toxic to humans and animals in higher quantities, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal...

) released by burning charcoal or wood in a wood gas generator
Wood gas generator
A wood gas generator is a gasification unit which converts timber or charcoal into wood gas, a syngas consisting of atmospheric nitrogen, carbon monoxide, hydrogen, traces of methane, and other gases, which - after cooling and filtering - can then be used to power an internal combustion engine or...

. In 1931 Tang Zhongming
Tang Zhongming
Tang Zhongming was a Chinese engineer and inventor. In 1931, he created an internal combustion engine powered by charcoal and mounted it in an automobile.-External links:*...

 developed an automobile powered by charcoal, and these cars were popular in China until the 1950s. In occupied France during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

, wood and wood charcoal production for such vehicles (called gazogènes) increased from pre-war figures of approximately fifty thousand tons a year to almost half a million tons in 1943.

Purification and filtration

Charcoal may be activated to increase its effectiveness as a filter. Activated charcoal
Activated carbon
Activated carbon, also called activated charcoal, activated coal or carbo activatus, is a form of carbon that has been processed to make it extremely porous and thus to have a very large surface area available for adsorption or chemical reactions.The word activated in the name is sometimes replaced...

 readily adsorbs
Adsorption
Adsorption is the adhesion of atoms, ions, biomolecules or molecules of gas, liquid, or dissolved solids to a surface. This process creates a film of the adsorbate on the surface of the adsorbent. It differs from absorption, in which a fluid permeates or is dissolved by a liquid or solid...

 a wide range of organic compounds dissolved or suspended in gases and liquids. In certain industrial processes, such as the purification of sucrose from cane sugar, impurities cause an undesirable color, which can be removed with activated charcoal.
It is also used to absorb odor
Odor
An odor or odour is caused by one or more volatilized chemical compounds, generally at a very low concentration, that humans or other animals perceive by the sense of olfaction. Odors are also commonly called scents, which can refer to both pleasant and unpleasant odors...

s and toxins in gases, such as air. Charcoal filters are also used in some types of gas mask
Gas mask
A gas mask is a mask put on over the face to protect the wearer from inhaling airborne pollutants and toxic gases. The mask forms a sealed cover over the nose and mouth, but may also cover the eyes and other vulnerable soft tissues of the face. Some gas masks are also respirators, though the word...

s. The medical use of activated charcoal is mainly the adsorption of poisons
Toxin
A toxin is a poisonous substance produced within living cells or organisms; man-made substances created by artificial processes are thus excluded...

, especially in the case of suicide attempts in which the patient has ingested a large amount of a drug. Activated charcoal is available without a prescription, so it is used for a variety of health-related applications. For example, it is often used to reduce discomfort (and embarrassment) due to excessive gas in the digestive tract.

Animal charcoal or bone black is the carbonaceous residue
Residue (chemistry)
In chemistry, residue is the material remaining after a distillation or an evaporation, or to a portion of a larger molecule, such as a methyl group. It may also refer to the undesired byproducts of a reaction....

 obtained by the dry distillation of bones. It contains only about 10% carbon, the remainder being calcium and magnesium
Magnesium
Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...

 phosphates (80%) and other inorganic material originally present in the bones. It is generally manufactured from the residues obtained in the glue
Animal glue
An animal glue is an adhesive that is created by prolonged boiling of animal connective tissue.These protein colloid glues are formed through hydrolysis of the collagen from skins, bones, tendons, and other tissues, similar to gelatin. The word "collagen" itself derives from Greek κόλλα kolla, glue...

 and gelatin
Gelatin
Gelatin is a translucent, colorless, brittle , flavorless solid substance, derived from the collagen inside animals' skin and bones. It is commonly used as a gelling agent in food, pharmaceuticals, photography, and cosmetic manufacturing. Substances containing gelatin or functioning in a similar...

 industries. Its decolorizing power was applied in 1812 by Derosne to the clarification of the syrup
Syrup
In cooking, a syrup is a thick, viscous liquid consisting primarily of a solution of sugar in water, containing a large amount of dissolved sugars but showing little tendency to deposit crystals...

s obtained in sugar
Sugar
Sugar is a class of edible crystalline carbohydrates, mainly sucrose, lactose, and fructose, characterized by a sweet flavor.Sucrose in its refined form primarily comes from sugar cane and sugar beet...

 refining; but its use in this direction has now greatly diminished, owing to the introduction of more active and easily managed reagents. It is still used to some extent in laboratory
Laboratory
A laboratory is a facility that provides controlled conditions in which scientific research, experiments, and measurement may be performed. The title of laboratory is also used for certain other facilities where the processes or equipment used are similar to those in scientific laboratories...

 practice. The decolorizing power is not permanent, becoming lost after using for some time; it may be revived, however, by washing and reheating. Wood charcoal also to some extent removes coloring material from solutions, but animal charcoal is generally more effective.

Art

Charcoal is used in art for drawing
Drawing
Drawing is a form of visual art that makes use of any number of drawing instruments to mark a two-dimensional medium. Common instruments include graphite pencils, pen and ink, inked brushes, wax color pencils, crayons, charcoal, chalk, pastels, markers, styluses, and various metals .An artist who...

, making rough sketches
Sketch (drawing)
A sketch is a rapidly executed freehand drawing that is not usually intended as a finished work...

 in painting
Painting
Painting is the practice of applying paint, pigment, color or other medium to a surface . The application of the medium is commonly applied to the base with a brush but other objects can be used. In art, the term painting describes both the act and the result of the action. However, painting is...

 and is one of the possible media for making a parsemage. It must usually be preserved by the application of a fixative
Fixative (drawing)
In drawing, a fixative is a liquid, similar to varnish, which is usually sprayed over a finished piece of artwork to better preserve it and prevent smudging....

. Artists generally utilize charcoal in three forms:
  • Vine charcoal is created by burning sticks of wood (usually willow
    Willow
    Willows, sallows, and osiers form the genus Salix, around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere...

     or linden/Tilia
    Tilia
    Tilia is a genus of about 30 species of trees native throughout most of the temperate Northern Hemisphere. The greatest species diversity is found in Asia, and the genus also occurs in Europe and eastern North America, but not western North America...

    ) into soft, medium, and hard consistencies.
  • Powdered charcoal is often used to "tone" or cover large sections of a drawing surface. Drawing over the toned areas will darken it further, but the artist can also lighten (or completely erase) within the toned area to create lighter tones.
  • Compressed charcoal charcoal powder mixed with gum binder
    Binder (material)
    -See also:*Adhesive or Glue*Cement*Paint...

     compressed into round or square sticks. The amount of binder determines the hardness of the stick. Compressed charcoal is used in charcoal pencil
    Pencil
    A pencil is a writing implement or art medium usually constructed of a narrow, solid pigment core inside a protective casing. The case prevents the core from breaking, and also from marking the user’s hand during use....

    s.

Horticulture

One additional use of charcoal was rediscovered recently in horticulture
Horticulture
Horticulture is the industry and science of plant cultivation including the process of preparing soil for the planting of seeds, tubers, or cuttings. Horticulturists work and conduct research in the disciplines of plant propagation and cultivation, crop production, plant breeding and genetic...

. Although American gardeners have been using charcoal for a short while, research
Research
Research can be defined as the scientific search for knowledge, or as any systematic investigation, to establish novel facts, solve new or existing problems, prove new ideas, or develop new theories, usually using a scientific method...

 on Terra preta
Terra preta
Terra preta is a type of very dark, fertile anthropogenic soil found in the Amazon Basin. Terra preta owes its name to its very high charcoal content, and was indeed made by adding a mixture of charcoal, bone, and manure to the otherwise relatively infertile Amazonian soil, and stays there for...

 soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...

s in the Amazon has found the widespread use of biochar
Biochar
Biochar or terra preta is charcoal created by pyrolysis of biomass. Biochar is under investigation as an approach to carbon sequestration via bio-energy with carbon capture and storage. Biochar thus has the potential to help mitigate climate change, via carbon sequestration...

 by pre-Columbian
Pre-Columbian
The pre-Columbian era incorporates all period subdivisions in the history and prehistory of the Americas before the appearance of significant European influences on the American continents, spanning the time of the original settlement in the Upper Paleolithic period to European colonization during...

 natives to turn otherwise unproductive soil into very rich soil. The technique may find modern application, both to improve soils and as a means of carbon sequestration.

Medicine

Charcoal was consumed in the past as dietary supplement for gastric problems in the form of charcoal biscuit
Charcoal biscuit
Charcoal biscuit is a biscuit based on a powdered willow charcoal or activated carbon mixed with ordinary flour, and made into dough with butter, sugar and eggs.- History :...

s. Now it can be consumed in tablet, capsule or powder form, for digestive effects. Research regarding its effectiveness is controversial. (Am J Gastroenterology 2005 Feb 100(2)397-400 and 1999 Jan 94(1) 208-12)

Red colobus
Red colobus
Red colobuses are Old World monkeys of the subgenus Piliocolobus in genus Procolobus. Some authors elevate Piliocolobus to a full genus, limiting Procolobus to the olive colobus. They are closely related to the black-and-white colobus monkeys and some species are often found in groups with the...

 monkeys in Africa have been observed eating charcoal for the purposes of self-medication. Their leafy diets contain high levels of cyanide, which may lead to indigestion. So they learned to consume charcoal, which absorbs the cyanide and relieves indigestion. This knowledge about supplementing their diet is transmitted from mother to infant.

Also, see Activated charcoal, medicinal applications.

Smoking

Special charcoals are used in smoking the hookah
Hookah
A hookah A hookah(Gujarati હૂકાહ) A hookah(Gujarati હૂકાહ) (Hindustani: हुक़्क़ा (Devanagari, (Nastaleeq) huqqah) also known as a waterpipe or narghile, is a single or multi-stemmed (often glass-based) instrument for smoking in which the smoke is cooled by water. The tobacco smoked is referred to...

 (Argeeleh in Arabic, Nargile in Turkish or Narghilea in Romanian). Lit coals are placed on top of foil which is placed over the tobacco bowl; through indirect heat the coals "cook" the tobacco to a temperature that does not burn it but produces smoke.

Environmental implications

Charcoal production at a sub-industrial level is one of the primary causes of deforestation in the Developing World. Charcoal production is usually illegal and nearly always unregulated. Massive forest destruction has been documented in areas such as Virunga National Park
Virunga National Park
The Virunga National Park , formerly named Albert National Park, is a 7800 square km National Park that stretches from the Virunga Mountains in the South, to the Rwenzori Mountains in the North, in the eastern Democratic Republic of Congo, bordering Volcanoes National Park in Rwanda and Rwenzori...

 in the Democratic Republic of Congo, where it is considered to be a primary threat to the survival of the mountain gorillas. Similar threats are found in Zambia
Zambia
Zambia , officially the Republic of Zambia, is a landlocked country in Southern Africa. The neighbouring countries are the Democratic Republic of the Congo to the north, Tanzania to the north-east, Malawi to the east, Mozambique, Zimbabwe, Botswana and Namibia to the south, and Angola to the west....

.

Colour and look

The colours and look of charcoal is widely used in fashion and graphic design, without any relation to the material in itself beyond just referencing the appearance.

See also

  • Binchōtan
    Binchotan
    is a mascot character, created by Japanese manga artist and produced by game goods company Alchemist.The name is a play on words: is a kind of charcoal, which is mainly used for cooking. However, -tan is a suffix created by the mispronunciation of -chan...

  • Biochar
    Biochar
    Biochar or terra preta is charcoal created by pyrolysis of biomass. Biochar is under investigation as an approach to carbon sequestration via bio-energy with carbon capture and storage. Biochar thus has the potential to help mitigate climate change, via carbon sequestration...

  • Pyrolysis
    Pyrolysis
    Pyrolysis is a thermochemical decomposition of organic material at elevated temperatures without the participation of oxygen. It involves the simultaneous change of chemical composition and physical phase, and is irreversible...

  • Shichirin
    Shichirin
    ]The shichirin is a small charcoal grill.-Description:The shichirin is a lightweight, compact, and easy-to-move cooking stove. Charcoal is chiefly used for the fuel of shichirin. It has had prototypes since ancient times, and it is said that shichirin roughly the same as today's were made in the...

  • Slash-and-char
    Slash-and-char
    Slash-and-char is an alternative to slash-and-burn that has a lesser effect on the environment. It is the practice of charring the biomass resulting from the slashing, instead of burning it as in the slash-and-burn practice....

  • Terra preta
    Terra preta
    Terra preta is a type of very dark, fertile anthropogenic soil found in the Amazon Basin. Terra preta owes its name to its very high charcoal content, and was indeed made by adding a mixture of charcoal, bone, and manure to the otherwise relatively infertile Amazonian soil, and stays there for...

  • Biomass briquettes
    Biomass briquettes
    Biomass briquettes are a biofuel substitute to coal and charcoal. They are used to heat industrial boilers in order to produce electricity from steam. The most common use of the briquettes are in the developing world, where energy sources are not as widely available...

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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