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71-583: Farrandsville Iron Furnace , also known as Lycoming Coal Co., is a historic iron furnace located at Colebrook Township in Clinton County, Pennsylvania about 6 miles northwest of Lock Haven . It was built between 1836 and 1837, and measures 43 feet square by 54 feet high. It is a rare example of an early attempt to adopt coke as a blast furnace fuel. It was listed on the National Register of Historic Places in 1991. Capitalists from Boston financed

142-408: A carbonate as byproduct: Thermal combustion is the most common source for carbon monoxide. Carbon monoxide is produced from the partial oxidation of carbon -containing compounds; it forms when there is not enough oxygen to produce carbon dioxide (CO 2 ), such as when operating a stove or an internal combustion engine in an enclosed space. A large quantity of CO byproduct is formed during

213-453: A bloomery is iron that is easily forgeable , it requires a low carbon content. The temperature and ratio of charcoal to iron ore must be carefully controlled to keep the iron from absorbing too much carbon and thus becoming unforgeable. Cast iron occurs when the iron absorbs 2% to 4% carbon. Because the bloomery is self- fluxing , the addition of limestone is not required to form a slag. The small particles of iron produced in this way fall to

284-399: A bloomery's size is increased, the iron ore is exposed to burning charcoal for a longer time. When combined with the strong air blast required to penetrate the large ore and charcoal stack, this may cause part of the iron to melt and become saturated with carbon in the process, producing unforgeable pig iron, which requires oxidation to be reduced into cast iron, steel, and iron. This pig iron

355-487: A carbon monoxide presence. Carbon monoxide poisoning is the most common type of fatal air poisoning in many countries. Acute exposure can also lead to long-term neurological effects such as cognitive and behavioural changes. Severe CO poisoning may lead to unconsciousness, coma and death. Chronic exposure to low concentrations of carbon monoxide may lead to lethargy, headaches, nausea, flu-like symptoms and neuropsychological and cardiovascular issues. Carbon monoxide has

426-406: A dative or dipolar bond . This causes a C←O polarization of the molecule, with a small negative charge on carbon and a small positive charge on oxygen. The other two bonding orbitals are each occupied by one electron from carbon and one from oxygen, forming (polar) covalent bonds with a reverse C→O polarization since oxygen is more electronegative than carbon. In the free carbon monoxide molecule,

497-417: A full bond. Thus, in valence bond terms, C≡O is the most important structure, while :C=O is non-octet, but has a neutral formal charge on each atom and represents the second most important resonance contributor. Because of the lone pair and divalence of carbon in this resonance structure, carbon monoxide is often considered to be an extraordinarily stabilized carbene . Isocyanides are compounds in which

568-432: A high iron content, it can also be broken up and may be recycled into the bloomery with the new ore. In operation, after the bloomery is heated typically with a wood fire, shifting to burning sized charcoal, iron ore and additional charcoal are introduced through the top. Again, traditional methods vary, but normally smaller charges of ore are added at the start of the main smelting sequence, increasing to larger amounts as

639-461: A higher carbon content) by manipulating the charge of and air flow to the bloomery is also possible. As the era of modern commercial steelmaking began, the word "bloom" was extended to another sense referring to an intermediate-stage piece of steel , of a size comparable to many traditional iron blooms, that was ready to be further worked into billet . The onset of the Iron Age in most parts of

710-539: A ligand, CO binds through carbon, forming a kind of triple bond. The lone pair on the carbon atom donates electron density to form a M-CO sigma bond . The two π* orbitals on CO bind to filled metal orbitals. The effect is related to the Dewar-Chatt-Duncanson model . The effects of the quasi-triple M-C bond is reflected in the infrared spectrum of these complexes. Whereas free CO vibrates at 2143 cm-1, its complexes tend to absorb near 1950 cm-1. [REDACTED] In

781-540: A mixture of an organometallic compound, potassium acetylenediolate 2 K · C 2 O 2 , potassium benzenehexolate 6 K C 6 O 6 , and potassium rhodizonate 2 K · C 6 O 6 . The compounds cyclohexanehexone or triquinoyl (C 6 O 6 ) and cyclopentanepentone or leuconic acid (C 5 O 5 ), which so far have been obtained only in trace amounts, can be regarded as polymers of carbon monoxide. At pressures exceeding 5 GPa , carbon monoxide converts to polycarbonyl ,

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852-405: A natural draft effect (into the range of 200 cm tall), and increasing bloom sizes into the range of 10–15 kg. Contemporary experimenters had routinely made blooms using Northern European-derived "short-shaft" furnaces with blown air supplies in the 5–10 kg range The use of waterwheels , spreading around the turn of the first millennium and used to power more massive bellows, allowed

923-417: A net negative charge δ remains at the carbon end and the molecule has a small dipole moment of 0.122  D . The molecule is therefore asymmetric: oxygen is more electron dense than carbon and is also slightly positively charged compared to carbon being negative. Carbon monoxide has a computed fractional bond order of 2.6, indicating that the "third" bond is important but constitutes somewhat less than

994-450: A noncarburized bloom, this pound, fold, and weld process resulted in a more homogeneous product and removed much of the slag. The process had to be repeated up to 15 times when high-quality steel was needed, as for a sword. The alternative was to carburize the surface of a finished product. Each welding's heat oxidises some carbon, so the master smith had to make sure enough carbon was in the starting mixture. In England and Wales, despite

1065-540: A solid polymer that is metastable at atmospheric pressure but is explosive. Carbon monoxide is conveniently produced in the laboratory by the dehydration of formic acid or oxalic acid , for example with concentrated sulfuric acid . Another method is heating an intimate mixture of powdered zinc metal and calcium carbonate , which releases CO and leaves behind zinc oxide and calcium oxide : Silver nitrate and iodoform also afford carbon monoxide: Finally, metal oxalate salts release CO upon heating, leaving

1136-416: A spongy mass referred to as the bloom . Because the bloom is typically porous , and its open spaces can be full of slag, the extracted mass must be beaten with heavy hammers to both compress voids and drive out any molten slag remaining. This process may require several additional heating and compaction cycles, working at high 'welding' temperatures. Iron treated this way is said to be wrought (worked), and

1207-431: A total of 10 electrons in the valence shell . Following the octet rule for both carbon and oxygen, the two atoms form a triple bond , with six shared electrons in three bonding molecular orbitals, rather than the usual double bond found in organic carbonyl compounds. Since four of the shared electrons come from the oxygen atom and only two from carbon, one bonding orbital is occupied by two electrons from oxygen, forming

1278-458: A wide range of functions across all disciplines of chemistry. The four premier categories of reactivity involve metal-carbonyl catalysis, radical chemistry, cation and anion chemistries. Most metals form coordination complexes containing covalently attached carbon monoxide. These derivatives, which are called metal carbonyls , tend to be more robust when the metal is in lower oxidation states. For example iron pentacarbonyl (Fe(CO) 5 )

1349-425: A wind-driven furnace was found in an excavation site. Such furnaces were powered by the monsoon winds and have been dated to 300 BC using radiocarbon-dating techniques. These ancient Lankan furnaces might have produced the best-quality steel for legendary Damascus swords as referred in earlier Syrian records. Field trials using replica furnaces confirmed that this furnace type uses a wind-based air-supply principle that

1420-467: Is isoelectronic with both cyanide anion CN and molecular nitrogen N 2 . Carbon monoxide is the simplest oxocarbon and is isoelectronic with other triply bonded diatomic species possessing 10 valence electrons, including the cyanide anion, the nitrosonium cation, boron monofluoride and molecular nitrogen . It has a molar mass of 28.0, which, according to the ideal gas law , makes it slightly less dense than air, whose average molar mass

1491-670: Is 28.8. The carbon and oxygen are connected by a triple bond that consists of a net two pi bonds and one sigma bond . The bond length between the carbon atom and the oxygen atom is 112.8  pm . This bond length is consistent with a triple bond, as in molecular nitrogen (N 2 ), which has a similar bond length (109.76 pm) and nearly the same molecular mass . Carbon–oxygen double bonds are significantly longer, 120.8 pm in formaldehyde , for example. The boiling point (82 K) and melting point (68 K) are very similar to those of N 2 (77 K and 63 K, respectively). The bond-dissociation energy of 1072 kJ/mol

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1562-551: Is an air-stable, distillable liquid. Nickel carbonyl is an example of a metal carbonyl complex that forms by the direct combination of carbon monoxide with the metal: C. Elschenbroich (2006). Organometallics . VCH. ISBN   978-3-527-29390-2 . These volatile complexes are often highly toxic. Some metal–CO complexes are prepared by decarbonylation of organic solvents, not from CO. For instance, iridium trichloride and triphenylphosphine react in boiling 2-methoxyethanol or DMF to afford IrCl(CO)(PPh 3 ) 2 . As

1633-529: Is distinct from either forced or natural draught, and show also that they are capable of producing high-carbon steel. Wrought iron was used in the construction of monuments such as the iron pillar of Delhi , built in the third century AD during the Gupta Empire . The latter was built using a towering series of disc-shaped iron blooms. Similar to China, high-carbon steel was eventually used in India, although cast iron

1704-485: Is formed during the formation of NO 2 , the balance of the sequence of chemical reactions starting with carbon monoxide and leading to the formation of ozone is: (where hν refers to the photon of light absorbed by the NO 2 molecule in the sequence) Although the creation of NO 2 is the critical step leading to low level ozone formation, it also increases this ozone in another, somewhat mutually exclusive way, by reducing

1775-670: Is high enough (for instance in an underground sea), formic acid will be formed: These reactions can take place in a few million years even at temperatures such as found on Pluto. Carbon monoxide is a temporary atmospheric pollutant in some urban areas, chiefly from the exhaust of internal combustion engines (including vehicles, portable and back-up generators, lawnmowers, power washers, etc.), but also from incomplete combustion of various other fuels (including wood, coal, charcoal, oil, paraffin, propane, natural gas, and trash). Large CO pollution events can be observed from space over cities. Carbon monoxide is, along with aldehydes , part of

1846-662: Is located in Fengxiang County , Shaanxi (a museum exists on the site today). The earliest records of bloomery-type furnaces in East Africa are discoveries of smelted iron and carbon in Nubia in ancient Sudan dated at least to the seventh to the sixth century BC. The ancient bloomeries that produced metal tools for the Nubians and Kushites produced a surplus for sale. All traditional sub-Saharan African iron-smelting processes are variants of

1917-521: Is present in small amounts (about 80 ppb ) in the Earth's atmosphere . Most of the rest comes from chemical reactions with organic compounds emitted by human activities and natural origins due to photochemical reactions in the troposphere that generate about 5 × 10 kilograms per year. Other natural sources of CO include volcanoes, forest and bushfires , and other miscellaneous forms of combustion such as fossil fuels . Small amounts are also emitted from

1988-496: Is stronger than that of N 2 (942 kJ/mol) and represents the strongest chemical bond known. The ground electronic state of carbon monoxide is a singlet state since there are no unpaired electrons. The strength of the C-O bond in carbon monoxide is indicated by the high frequency of its vibration, 2143 cm . For comparison, organic carbonyls such as ketones and esters absorb at around 1700 cm . Carbon and oxygen together have

2059-445: Is the most common type of fatal air poisoning in many countries. Carbon monoxide has important biological roles across phylogenetic kingdoms. It is produced by many organisms, including humans. In mammalian physiology, carbon monoxide is a classical example of hormesis where low concentrations serve as an endogenous neurotransmitter ( gasotransmitter ) and high concentrations are toxic resulting in carbon monoxide poisoning . It

2130-731: Is the partial combustion of carbon-containing compounds. Numerous environmental and biological sources generate carbon monoxide. In industry, carbon monoxide is important in the production of many compounds, including drugs, fragrances, and fuels. Upon emission into the atmosphere, carbon monoxide affects several processes that contribute to climate change . Indoors CO is one of the most acutely toxic contaminants affecting indoor air quality . CO may be emitted from tobacco smoke and generated from malfunctioning fuel burning stoves (wood, kerosene, natural gas, propane) and fuel burning heating systems (wood, oil, natural gas) and from blocked flues connected to these appliances. Carbon monoxide poisoning

2201-439: Is the preparation of the charcoal and the iron ore. Charcoal is nearly pure carbon , which, when burned, both produces the high temperature needed for the smelting process and provides the carbon monoxide needed for reduction of the metal. The ore is broken into small pieces and usually roasted in a fire, to make rock-based ores easier to break up, bake out some impurities, and (to a lesser extent) to remove any moisture in

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2272-575: Is the second-most common diatomic molecule in the interstellar medium , after molecular hydrogen . Because of its asymmetry, this polar molecule produces far brighter spectral lines than the hydrogen molecule, making CO much easier to detect. Interstellar CO was first detected with radio telescopes in 1970. It is now the most commonly used tracer of molecular gas in general in the interstellar medium of galaxies, as molecular hydrogen can only be detected using ultraviolet light, which requires space telescopes . Carbon monoxide observations provide much of

2343-412: Is very little CO in the atmosphere of Pluto , which seems to have been formed from comets. This may be because there is (or was) liquid water inside Pluto. Carbon monoxide can react with water to form carbon dioxide and hydrogen: This is called the water-gas shift reaction when occurring in the gas phase, but it can also take place (very slowly) in an aqueous solution. If the hydrogen partial pressure

2414-542: The Nittany Valley . The financial Panic of 1837 forced the furnace to close in 1838. A brick furnace was then built on the same property and was later owned by Harbison-Walker Refractories Company who deeded it to the Clinton County Historical Society in 1951. Bloomery A bloomery is a type of metallurgical furnace once used widely for smelting iron from its oxides . The bloomery

2485-631: The Nsukka region of southeast Nigeria in what is now Igboland . The site of Gbabiri, in the Central African Republic , has also yielded evidence of iron metallurgy, from a reduction furnace and blacksmith workshop, with earliest dates of 896–773 and 907–796 BC, respectively. During a hydroelectric plant project, in the southern foothills of the Central Highlands, Samanalawewa, in Sri Lanka ,

2556-453: The hydroxyl radical , OH) that would otherwise destroy methane. Through natural processes in the atmosphere, it is oxidized to carbon dioxide and ozone. Carbon monoxide is short-lived in the atmosphere (with an average lifetime of about one to two months), and spatially variable in concentration. Due to its long lifetime in the mid-troposphere, carbon monoxide is also used as a tracer for pollutant plumes. Beyond Earth, carbon monoxide

2627-577: The missions , encomiendas , and pueblos . As part of the Franciscan Spanish missions in Alta California , the "Catalan forges" at Mission San Juan Capistrano from the 1790s are the oldest existing facilities of their kind in the present day state of California . The bloomeries' sign proclaims the site as being "part of Orange County 's first industrial complex". The archaeology at Jamestown Virginia ( circa 1610–1615 ) had recovered

2698-410: The "silent killer". It can be found in confined areas of poor ventilation in both surface mines and underground mines. The most common sources of carbon monoxide in mining operations are the internal combustion engine and explosives; however, in coal mines, carbon monoxide can also be found due to the low-temperature oxidation of coal. The idiom " Canary in the coal mine " pertained to an early warning of

2769-607: The 12th century. The oldest bloomery in Sweden, also found in the same area, has been carbon-14 dated to 700 BCE. Bloomeries survived in Spain and southern France as Catalan forges into the mid-19th century, and in Austria as the Stückofen to 1775. Iron smelting was unknown in pre-Columbian America . Excavations at L'Anse aux Meadows , Newfoundland, have found considerable evidence for

2840-428: The O is replaced by an NR (R = alkyl or aryl) group and have a similar bonding scheme. If carbon monoxide acts as a ligand , the polarity of the dipole may reverse with a net negative charge on the oxygen end, depending on the structure of the coordination complex . See also the section "Coordination chemistry" below. Theoretical and experimental studies show that, despite the greater electronegativity of oxygen,

2911-481: The West, iron began to be used around 1200 BC. China has long been considered the exception to the general use of bloomeries. The Chinese are thought to have skipped the bloomery process completely, starting with the blast furnace and the finery forge to produce wrought iron; by the fifth century BC, metalworkers in the southern state of Wu had invented the blast furnace and the means to both cast iron and to decarburize

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2982-773: The arrival of the blast furnace in the Weald in about 1491, bloomery forges, probably using waterpower for the hammer and the bellows, were operating in the West Midlands region beyond 1580. In Furness and Cumberland , they operated into the early 17th century and the last one in England (near Garstang ) did not close until about 1770. One of the oldest-known blast furnaces in Europe has been found in Lapphyttan in Sweden , carbon-14 dated to be from

3053-711: The bloomery process. There is considerable discussion about the origins of iron metallurgy in Africa . Smelting in bloomery type furnaces in West Africa and forging of tools appeared in the Nok culture of central Nigeria by at least 550 BC and possibly several centuries earlier. Also, evidence indicates iron smelting with bloomery-style furnaces dated to 750 BC in Opi (Augustin Holl 2009) and Lejja dated to 2,000 BC (Pamela Eze-Uzomaka 2009), both sites in

3124-409: The bloomery to become larger and hotter, with associated trip hammers allowing the consolidation forging of the larger blooms created. Progressively larger bloomeries were constructed in the late 14th century, with a capacity of about 15 kg on average, though exceptions did exist. European average bloom sizes quickly rose to 300 kg, where they levelled off until the demise of the bloomery. As

3195-474: The bottom of the furnace, where they combine with molten slag, often consisting of fayalite , a compound of silicon , oxygen , and iron mixed with other impurities from the ore. The hot liquid slag, running to the bottom of the furnace, cools against the base and lower side walls of the furnace, effectively forming a bowl still containing fluid slag. As the individual iron particles form, they fall into this bowl and sinter together under their own weight, forming

3266-415: The bottom, one or more pipes (made of clay or metal) enter through the side walls. These pipes, called tuyeres , allow air to enter the furnace, either by natural draught or forced with bellows or a trompe . An opening at the bottom of the bloomery may be used to remove the bloom, or the bloomery can be tipped over and the bloom removed from the top. The first step taken before the bloomery can be used

3337-443: The carbon-rich pig iron produced in a blast furnace to a low-carbon, wrought iron-like material. Recent evidence, however, shows that bloomeries were used earlier in ancient China , migrating in from the west as early as 800 BC, before being supplanted by the locally developed blast furnace. Supporting this theory was the discovery of "more than ten" iron-digging implements found in the tomb of Duke Jing of Qin (d. 537 BCE), whose tomb

3408-436: The dipole moment points from the more-negative carbon end to the more-positive oxygen end. The three bonds are in fact polar covalent bonds that are strongly polarized. The calculated polarization toward the oxygen atom is 71% for the σ-bond and 77% for both π-bonds . The oxidation state of carbon in carbon monoxide is +2 in each of these structures. It is calculated by counting all the bonding electrons as belonging to

3479-465: The furnace's construction starting in 1836. John Thomas likely supervised construction and John P. Salmon was the master mason. It was equipped with Scottish machinery installed by Scot James Ralston, and produced fifty tons of pig iron per week. Bituminous coal was mined at nearby Minersville and transported by inclined plane. Transportation of iron ore was from over 100 miles away via canal, but this proved difficult, as did transportation of flux from

3550-549: The information about the molecular clouds in which most stars form . Beta Pictoris , the second brightest star in the constellation Pictor , shows an excess of infrared emission compared to normal stars of its type, which is caused by large quantities of dust and gas (including carbon monoxide) near the star. In the atmosphere of Venus carbon monoxide occurs as a result of the photodissociation of carbon dioxide by electromagnetic radiation of wavelengths shorter than 169 nm . It has also been identified spectroscopically on

3621-519: The iron content of the primary bog iron ore found in the purpose built 'furnace hut' with the iron remaining in that slag, an estimated 3 kg iron bloom was produced. At a yield of at best 20% from what is a good iron rich ore, this suggests the workers processing the ore had not been particularly skilled. This supports the idea that iron processing knowledge was widespread and not restricted to major centers of trade and commerce. Archaeologists also found 98 nail, and importantly, ship rivet fragments, at

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3692-439: The main sources of indoor CO emission come from cooking and heating devices that burn fossil fuels and are faulty, incorrectly installed or poorly maintained. Appliance malfunction may be due to faulty installation or lack of maintenance and proper use. In low- and middle-income countries the most common sources of CO in homes are burning biomass fuels and cigarette smoke. Miners refer to carbon monoxide as " whitedamp " or

3763-468: The more electronegative oxygen. Only the two non-bonding electrons on carbon are assigned to carbon. In this count, carbon then has only two valence electrons in the molecule compared to four in the free atom. Carbon monoxide occurs in various natural and artificial environments. Photochemical degradation of plant matter for example generates an estimated 60 million tons/year. Typical concentrations in parts per million are as follows: Carbon monoxide (CO)

3834-572: The ocean, and from geological activity because carbon monoxide occurs dissolved in molten volcanic rock at high pressures in the Earth's mantle . Because natural sources of carbon monoxide vary from year to year, it is difficult to accurately measure natural emissions of the gas. Carbon monoxide has an indirect effect on radiative forcing by elevating concentrations of direct greenhouse gases , including methane and tropospheric ozone . CO can react chemically with other atmospheric constituents (primarily

3905-526: The ore. Any large impurities (as silica) in the ore can be removed as it is crushed. The desired particle size depends primarily on which of several ore types may be available, which will also have a relationship to the layout and operation of the furnace, of which a number of regional, historic/traditional forms exist. Natural iron ores can vary considerably in oxide form ( Fe 2 O 3 / Fe 3 O 4 / FeO(OH) ), and importantly in relative iron content. Since slag from previous blooms may have

3976-404: The oxidative processes for the production of chemicals. For this reason, the process off-gases have to be purified. Many methods have been developed for carbon monoxide production. A major industrial source of CO is producer gas , a mixture containing mostly carbon monoxide and nitrogen, formed by combustion of carbon in air at high temperature when there is an excess of carbon. In an oven, air

4047-482: The presence of metal catalysts. With main group reagents, CO undergoes several noteworthy reactions. Chlorination of CO is the industrial route to the important compound phosgene . With borane CO forms the adduct H 3 BCO , which is isoelectronic with the acylium cation [H 3 CCO] . CO reacts with sodium to give products resulting from C−C coupling such as sodium acetylenediolate 2 Na · C 2 O 2 . It reacts with molten potassium to give

4118-538: The presence of strong acids, alkenes react with carboxylic acids . Hydrolysis of this species (an acylium ion ) gives the carboxylic acid, a net process known as the Koch–Haaf reaction . In the Gattermann–Koch reaction , arenes are converted to benzaldehyde derivatives in the presence of CO, AlCl 3 , and HCl . A mixture of hydrogen gas and CO reacts with alkenes to give aldehydes. The process requires

4189-472: The processing of bog iron and the production of iron in a bloomery by the Norse. The cluster of Viking Age ( c.  1000 –1022 AD) at L'Anse aux Meadows are situated on a raised marine terrace, between a sedge peat bog and the ocean. Estimates from the smaller amount of slag recovered archaeologically suggest 15 kg of slag was produced during what appears to have been a single smelting attempt. By comparing

4260-418: The quantity of NO that is available to react with ozone. Carbon monoxide is one of the most acutely toxic indoor air contaminants . Carbon monoxide may be emitted from tobacco smoke and generated from malfunctioning fuel burning stoves (wood, kerosene, natural gas, propane) and fuel burning heating systems (wood, oil, natural gas) and from blocked flues connected to these appliances. In developed countries

4331-576: The remains of a simple short-shaft bloomery furnace, likely intended as yet another "resource test" like the one in Vinland much earlier. The English settlers of the Thirteen Colonies were prevented by law from manufacture; for a time, the British sought to situate most of the skilled artisanry at domestic locations. In fact, this was one of the problems that led to the revolution. The Falling Creek Ironworks

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4402-418: The resulting iron, with reduced amounts of slag, is called wrought iron or bar iron. Because of the creation process, individual blooms can often have differing carbon contents between the original top and bottom surfaces, differences that will also be somewhat blended together through the flattening, folding, and hammer-welding sequences. Intentionally producing blooms that are coated in steel (i.e. iron with

4473-510: The series of cycles of chemical reactions that form photochemical smog . It reacts with hydroxyl radical ( OH) to produce a radical intermediate HOCO, which rapidly transfers its radical hydrogen to O 2 to form peroxy radical (HO 2 ) and carbon dioxide (CO 2 ). Peroxy radical subsequently reacts with nitrogen oxide (NO) to form nitrogen dioxide (NO 2 ) and hydroxyl radical. NO 2 gives O( P) via photolysis, thereby forming O 3 following reaction with O 2 . Since hydroxyl radical

4544-542: The site as well as considerable evidence for woodworking – which points to boat or possibly ship repairs being undertaken at the site. (An important consideration remains that a potential 3 kg raw bloom most certainly does not make enough refined bar to manufacture the 3 kg of recovered nails and rivets.) In the Spanish colonization of the Americas , bloomeries or "Catalan forges" were part of "self-sufficiency" at some of

4615-404: The smelt progresses. Overall, a typical ratio of total charcoal to ore added is in a roughly one-to-one ratio. Inside the furnace, carbon monoxide from the incomplete combustion of the charcoal reduces the iron oxides in the ore to metallic iron without melting the ore; this allows the bloomery to operate at lower temperatures than the melting temperature of the ore. As the desired product of

4686-433: The surface of Neptune's moon Triton . Solid carbon monoxide is a component of comets . The volatile or "ice" component of Halley's Comet is about 15% CO. At room temperature and at atmospheric pressure, carbon monoxide is actually only metastable (see Boudouard reaction ) and the same is true at low temperatures where CO and CO 2 are solid, but nevertheless it can exist for billions of years in comets. There

4757-515: The world coincides with the first widespread use of the bloomery. While earlier examples of iron are found, their high nickel content indicates that this is meteoric iron . Other early samples of iron may have been produced by accidental introduction of iron ore in copper-smelting operations. Iron appears to have been smelted in the Middle East as early as 3000 BC, but coppersmiths, not being familiar with iron, did not put it to use until much later. In

4828-512: Was considered a waste product detracting from the largest bloomeries' yield, and early blast furnaces , identical in construction, but dedicated to the production of molten iron, were not built until the 14th century. Bloomery type furnaces typically produced a range of iron products from very low-carbon iron to steel containing around 0.2–1.5% carbon. The master smith had to select pieces of low-carbon iron, carburize them, and pattern-weld them together to make steel sheets. Even when applied to

4899-427: Was not used for architecture until modern times. Early European bloomeries were relatively small, primarily due to the mechanical limits of human-powered bellows and the amount of force possible to apply with hand-driven sledge hammers. Those known archaeologically from the pre-Roman Iron Age tend to be in the 2 kg range, produced in low shaft furnaces. Roman-era production often used furnaces tall enough to create

4970-455: Was the earliest form of smelter capable of smelting iron. Bloomeries produce a porous mass of iron and slag called a bloom . The mix of slag and iron in the bloom, termed sponge iron , is usually consolidated and further forged into wrought iron . Blast furnaces , which produce pig iron , have largely superseded bloomeries. A bloomery consists of a pit or chimney with heat-resistant walls made of earth, clay , or stone . Near

5041-554: Was the first in the United States. The Neabsco Iron Works is an example of the early Virginian effort to form a workable American industry. The earliest iron forge in colonial Pennsylvania was Thomas Rutter 's bloomery near Pottstown , founded in 1716. In the Adirondacks , New York, new bloomeries using the hot blast technique were built in the 19th century. Carbon monoxide The most common source of carbon monoxide

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