query: What is the chemical formula of methane?

title: Methane

text: Methane Methane ( or ) is a chemical compound with the chemical formula (one atom of carbon and four atoms of hydrogen). It is a group-14 hydride and the simplest alkane, and is the main constituent of natural gas. The relative abundance of methane on Earth makes it an attractive fuel, though capturing and storing it poses challenges due to its gaseous state under normal conditions for temperature and pressure. Natural methane is found both below ground and under the sea floor. When it reaches the surface and the atmosphere, it is known as atmospheric methane. The Earth's atmospheric methane

title: Methane

text: in the Martian atmosphere. Methane could be produced by a non-biological process called ’'serpentinization" involving water, carbon dioxide, and the mineral olivine, which is known to be common on Mars. Methane Methane ( or ) is a chemical compound with the chemical formula (one atom of carbon and four atoms of hydrogen). It is a group-14 hydride and the simplest alkane, and is the main constituent of natural gas. The relative abundance of methane on Earth makes it an attractive fuel, though capturing and storing it poses challenges due to its gaseous state under normal conditions for temperature and pressure.

title: Tris(dimethylamino)methane

text: Tris(dimethylamino)methane Tris(dimethylamino)methane (TDAM) is the simplest representative of the tris(dialkylamino)methanes of the general formula (RN)CH in which three of the four of methane's hydrogen atoms are replaced by dimethylamino groups (−N(CH)). Tris(dimethylamino)methane can be regarded as both an amine and an orthoamide. Tris(dimethylamino)methane is a strong base and can be used as a formylation agent, as aminomethylenation reagent and as a source for the basic bis(dimethylamino)carbene of the formula (RN)C∶. Tris(dimethylamino)methane is formed in the reaction of N,N,N′,N′-Tetramethylformamidinium chloride (TMF-Cl) or bis(dimethylamino)acetonitrile with lithium dimethylamide or sodium dimethylamide with yields between 55 and 84%. From dimethylamine and trimethoxyborane sodium dimethylamide

title: Oxidative coupling of methane

text: methyl radicals with the surface and oxygen in the gas phase, which produce (undesirable) carbon monoxide and carbon dioxide. Direct conversion of methane into other useful products is one of the most challenging subjects to be studied in heterogeneous catalysis. Methane activation is difficult because of its thermodynamic stability with a noble gas like electronic configuration. The tetrahedral arrangement of strong C–H bonds (435 kJ/mol) offer no functional group, magnetic moments or polar distributions to undergo chemical attack. This makes methane less reactive than nearly all of its conversion products, limiting efficient utilization of natural gas, the world’s most abundant

title: Chemical formula

text: a different connectivity from other molecules that can be formed using the same atoms in the same proportions (isomers). The formula (CH)CH implies a central carbon atom connected to one hydrogen atom and three CH groups. The same number of atoms of each element (10 hydrogens and 4 carbons, or CH) may be used to make a straight chain molecule, "n"-butane: CHCHCHCH. In any given chemical compound, the elements always combine in the same proportion with each other. This is the law of constant composition. The law of constant composition says that, in any particular chemical compound, all samples of

title: Methane

text: name "methane" was coined in 1866 by the German chemist August Wilhelm von Hofmann. The name was derived from methanol. Etymologically, the word ""methane"" is coined from the chemical suffix ""-ane"", which denotes substances belonging to the alkane family; and the word ""methyl"", which is derived from the German ""methyl"" (A.D.1840) or directly from the French ""méthyle"" which is a back-formation from the French ""méthylène"" (corresponding to English "methylene"), the root of which is coined from the Greek ""methy"" (related to English "mead") and ""hyle"" (meaning "wood"). The radical is named after this because it was first detected in wood

title: Chemical formula

text: that compound will be made up of the same elements in the same proportion or ratio. For example, any water molecule is always made up of two hydrogen atoms and one oxygen atom in a 2:1 ratio. If we look at the relative masses of oxygen and hydrogen in a water molecule, we see that 94% of the mass of a water molecule is accounted for by oxygen and the remaining 6% is the mass of hydrogen. This mass proportion will be the same for any water molecule. The alkene called but-2-ene has two isomers, which the chemical formula CHCH=CHCH

title: Tris(dimethylamino)methane

text: compounds. The anions thus formed add to the formamidinium cations which in turn eliminate dimethylamine and react to form dimethylaminomethylene compounds (= CH−N(CH)) or amidines by aminomethyleneation. Reaction to form a methyl α-cyano-β-dimethylaminoacrylate: Reaction to form "N","N"-dimethyl-"N"′-"p"-nitrophenylformamidine: Aminomethylenation provides intermediates for the synthesis of heterocycles such as pyrimidines, pyrazoles, 1,4-dihydropyridines and indoles. "N","N","N"′,"N"′-Tetramethylselenourea is accessible by the extended heating of tris(dimethylamino)methane with selenium in xylene, bis(dimethylamino)carbene is suggested as an intermediate. Tris(dimethylamino)methane Tris(dimethylamino)methane (TDAM) is the simplest representative of the tris(dialkylamino)methanes of the general formula (RN)CH in which three of the four of methane's hydrogen atoms are replaced by dimethylamino

title: Atmospheric methane

text: 2013 study by Miller "et al." indicates that current greenhouse gas reduction policies in the US are based on what appear to be significant underestimates of anthropogenic methane emissions. The authors state: We find greenhouse gas emissions from agriculture and fossil fuel extraction and processing ("i.e.," oil and/or natural gas) are likely a factor of two or greater than cited in existing studies. The direct radiative greenhouse gas forcing effect has been estimated at 0.5 W/m. Methane is a strong GHG with a global warming potential 84 times greater than CO in a 20-year time frame; Methane is not as

title: Methane

text: natural gas, or LNG). While leaks from a refrigerated liquid container are initially heavier than air due to the increased density of the cold gas, the gas at ambient temperature is lighter than air. Gas pipelines distribute large amounts of natural gas, of which methane is the principal component. Methane is used as a fuel for ovens, homes, water heaters, kilns, automobiles, turbines, and other things. Activated carbon is used to store methane. Liquid methane is also used as a rocket fuel when combined with liquid oxygen, as in the BE-4 and Raptor engines. Methane is important for electricity generation

title: Methane

text: important source of Arctic methane. Methane is an important greenhouse gas with a global warming potential of 34 compared to CO over a 100-year period, and 72 over a 20-year period. The Earth's atmospheric methane concentration has increased by about 150% since 1750, and it accounts for 20% of the total radiative forcing from all of the long-lived and globally mixed greenhouse gases (these gases don't include water vapor which is by far the largest component of the greenhouse effect). Methane is essentially insoluble in water, but significant deposits of methane clathrate have been found under sediments on the ocean

title: Methane clathrate

text: Methane clathrate Methane clathrate (CH·5.75HO) or (4CH·23HO), also called methane hydrate, hydromethane, methane ice, fire ice, natural gas hydrate, or gas hydrate, is a solid clathrate compound (more specifically, a clathrate hydrate) in which a large amount of methane is trapped within a crystal structure of water, forming a solid similar to ice. Originally thought to occur only in the outer regions of the Solar System, where temperatures are low and water ice is common, significant deposits of methane clathrate have been found under sediments on the ocean floors of the Earth. Methane clathrates are common constituents of the shallow

title: Methane clathrate

text: gas at the terminal would require a smaller refrigeration plant and less energy than LNG would. Offsetting this, for 100 tonnes of methane transported, 750 tonnes of methane hydrate would have to be transported; since this would require a ship of 7.5 times greater displacement, or require more ships, it is unlikely to prove economically feasible. Methane clathrate Methane clathrate (CH·5.75HO) or (4CH·23HO), also called methane hydrate, hydromethane, methane ice, fire ice, natural gas hydrate, or gas hydrate, is a solid clathrate compound (more specifically, a clathrate hydrate) in which a large amount of methane is trapped within a crystal

title: Methane

text: in industrial plants via biological route is called biogas. A more synthetic method to produce methane is hydrogenating carbon dioxide through the Sabatier process. Methane is also a side product of the hydrogenation of carbon monoxide in the Fischer–Tropsch process, which is practiced on a large scale to produce longer-chain molecules than methane. Example of large-scale coal-to-methane gasification is the Great Plains Synfuels plant, started in 1984 in Beulah, North Dakota as a way to develop abundant local resources of low-grade lignite, a resource that is otherwise very hard to transport for its weight, ash content, low calorific value and

title: Methane clathrate

text: of data for global warming research, along with oxygen and carbon dioxide. Methane hydrates were discovered in Russia in the 1960s, and studies for extracting gas from it emerged at the beginning of the 21st century. The nominal methane clathrate hydrate composition is (CH)(HO), or 1 mole of methane for every 5.75 moles of water, corresponding to 13.4% methane by mass, although the actual composition is dependent on how many methane molecules fit into the various cage structures of the water lattice. The observed density is around 0.9 g/cm, which means that methane hydrate will float to the surface of

title: Landauer formula

text: nanoscale conductor is given by the sum of all the transmission possibilities that an electron has when propagating with an energy equal to the chemical potential, formula_5. A generalization of the Landauer formula for multiple probes is the Landauer-Büttiker formula, proposed by Landauer and . If probe formula_6 has voltage formula_7 (that is, its chemical potential is formula_8), and formula_9 is the sum of transmission probabilities from probe formula_10 to probe formula_6 (note that formula_9 may or may not equal formula_13), the net current leaving probe formula_14 is Landauer formula The Landauer formula—named after Rolf Landauer, who first suggested its

title: Chemical formula

text: of chemical formulas. For example, alcohols may be represented by the formula CHOH ("n" ≥ 1), giving the homologs methanol, ethanol, propanol for "n"=1–3. The Hill system (or Hill notation) is a system of writing empirical chemical formulas, molecular chemical formulas and components of a condensed formula such that the number of carbon atoms in a molecule is indicated first, the number of hydrogen atoms next, and then the number of all other chemical elements subsequently, in alphabetical order of the chemical symbols. When the formula contains no carbon, all the elements, including hydrogen, are listed alphabetically. By sorting formulas

title: Chemical formula

text: Chemical formula The connectivity of a molecule often has a strong influence on its physical and chemical properties and behavior. Two molecules composed of the same numbers of the same types of atoms (i.e. a pair of isomers) might have completely different chemical and/or physical properties if the atoms are connected differently or in different positions. In such cases, a structural formula is useful, as it illustrates which atoms are bonded to which other ones. From the connectivity, it is often possible to deduce the approximate shape of the molecule. A condensed chemical formula may represent the types and spatial

title: Chemical formula

text: according to the number of atoms of each element present in the formula according to these rules, with differences in earlier elements or numbers being treated as more significant than differences in any later element or number—like sorting text strings into lexicographical order—it is possible to collate chemical formulas into what is known as Hill system order. The Hill system was first published by Edwin A. Hill of the United States Patent and Trademark Office in 1900. It is the most commonly used system in chemical databases and printed indexes to sort lists of compounds. A list of formulas in

title: Oxidative coupling of methane

text: Oxidative coupling of methane The oxidative coupling of methane (OCM) is a type of chemical reaction discovered in the 1980s for the direct conversion of natural gas, primarily consisting of methane, into value-added chemicals. The principal desired product of OCM is ethylene, the world’s largest commodity chemical and the chemical industry's fundamental building block. While converting methane to ethylene would offer enormous economic benefits, it is a major scientific challenge. Thirty years of research failed to produce a commercial OCM catalyst, preventing this process from commercial applications. Ethylene derivatives are found in food packaging, eyeglasses, cars, medical devices, lubricants, engine

title: Chemical formula

text: formulas. See IUPAC nomenclature of organic chemistry and IUPAC nomenclature of inorganic chemistry 2005 for examples. In addition, linear naming systems such as International Chemical Identifier (InChI) allow a computer to construct a structural formula, and simplified molecular-input line-entry system (SMILES) allows a more human-readable ASCII input. However, all these nomenclature systems go beyond the standards of chemical formulas, and technically are chemical naming systems, not formula systems. For polymers in condensed chemical formulas, parentheses are placed around the repeating unit. For example, a hydrocarbon molecule that is described as CH(CH)CH, is a molecule with fifty repeating units. If the

title: Chemical formula

text: on), and the visual aspects suggesting the structure of an endohedral fullerene. Chemical formulas most often use integers for each element. However, there is a class of compounds, called non-stoichiometric compounds, that cannot be represented by small integers. Such a formula might be written using decimal fractions, as in FeO, or it might include a variable part represented by a letter, as in FeO, where x is normally much less than 1. A chemical formula used for a series of compounds that differ from each other by a constant unit is called a "general formula". It generates a homologous series

title: Chemical formula

text: arrangement of bonds in a simple chemical substance, though it does not necessarily specify isomers or complex structures. For example, ethane consists of two carbon atoms single-bonded to each other, with each carbon atom having three hydrogen atoms bonded to it. Its chemical formula can be rendered as CHCH. In ethylene there is a double bond between the carbon atoms (and thus each carbon only has two hydrogens), therefore the chemical formula may be written: CHCH, and the fact that there is a double bond between the carbons is implicit because carbon has a valence of four. However, a more

title: Methane

text: atmosphere. As a gas it is flammable over a range of concentrations (5.4–17%) in air at standard pressure. Solid methane exists in several modifications. Presently nine are known. Cooling methane at normal pressure results in the formation of methane I. This substance crystallizes in the cubic system (space group Fmm). The positions of the hydrogen atoms are not fixed in methane I, i.e. methane molecules may rotate freely. Therefore, it is a plastic crystal. The primary chemical reactions of methane are combustion, steam reforming to syngas, and halogenation. In general, methane reactions are difficult to control. Partial oxidation to methanol,

title: Chemical formula

text: Hill system order is arranged alphabetically, as above, with single-letter elements coming before two-letter symbols when the symbols begin with the same letter (so "B" comes before "Be", which comes before "Br"). The following example formulae are written using the Hill system, and listed in Hill order: Chemical formula The connectivity of a molecule often has a strong influence on its physical and chemical properties and behavior. Two molecules composed of the same numbers of the same types of atoms (i.e. a pair of isomers) might have completely different chemical and/or physical properties if the atoms are connected differently or

title: Methane reformer

text: Methane reformer A methane reformer is a device based on steam reforming, autothermal reforming or partial oxidation and is a type of chemical synthesis which can produce pure hydrogen gas from methane using a catalyst. There are multiple types of reformers in development but the most common in industry are autothermal reforming (ATR) and steam methane reforming (SMR). Most methods work by exposing methane to a catalyst (usually nickel) at high temperature and pressure. Steam reforming (SR), sometimes referred to as steam methane reforming (SMR) uses an external source of hot gas to heat tubes in which a catalytic reaction

title: Atmospheric methane

text: to find ways to use or sell methane that would otherwise be released from the coal mine into the atmosphere. A portable methane detector has been developed which, mounted in a vehicle, can detect excess levels of methane in the ambient atmosphere and differentiate between natural methane from rotting vegetation or manure and gas leaks. As of 2013 the technology was being deployed by Pacific Gas & Electric. Methane is typically measured using gas chromatography. Gas chromatography is a type of chromatography used for separating or analyzing chemical compounds. It is less expensive in general, compared to more advanced methods,

title: Methane reformer

text: the range of 815 to 925 °C. However, analyses have shown that even though it is more costly to construct, a well-designed SMR can produce hydrogen more cost-effectively than an ATR. Methane reformer A methane reformer is a device based on steam reforming, autothermal reforming or partial oxidation and is a type of chemical synthesis which can produce pure hydrogen gas from methane using a catalyst. There are multiple types of reformers in development but the most common in industry are autothermal reforming (ATR) and steam methane reforming (SMR). Most methods work by exposing methane to a catalyst (usually nickel)

title: Coalbed methane extraction

text: or laboratory derived sorption isotherm methane storage capacity data. Laboratory sorption isotherms provide information about the storage capacity of a coal sampleif these are measured under geological realistic pressure and temperature conditions. Thus, the maximum gas content which can be expected for methane recovery can be assessed from such laboratory isotherm measurements. The total gas content by the indirect methods is based on the empirical formula given by Meinser and Kim. The quantity of gas is determined by Meisner and Kim formula with using the moisture content, volatile content, volume of methane adsorbed on wet coal, fixed carbon, thickness of

title: Atmospheric methane

text: into the atmosphere are directly related to temperature and moisture. Thus, the natural environmental changes that occur during seasonal change act as a major control of methane emission. Additionally, even changes in temperature during the day can affect the amount of methane that is produced and consumed. For example, plants that produce methane can emit as much as two to four times more methane during the day than during the night. This is directly related to the fact that plants tend to rely on solar energy to enact chemical processes. Additionally, methane emissions are affected by the level of water

title: Methane chimney

text: Methane chimney A methane chimney or gas chimney is a rising column of natural gas, mainly methane within a water or sediment column. The contrast in physical properties between the gas phase and the surrounding water makes such chimneys visible in oceanographic and geophysical data. In some cases, gas bubbles released at the seafloor may dissolve before they reach the ocean surface, but the increased hydrocarbon concentration may still be measured by chemical oceanographic techniques. In some locations along Russia’s northern coast, methane rising from the sea floor to the surface has caused the sea to foam. However, most methane

title: Chemical formula

text: as Cs[BH]. Parentheses ( ) can be nested inside brackets to indicate a repeating unit, as in [Co(NH)]Cl. Here, (NH) indicates that the ion contains six NH groups bonded to cobalt, and [ ] encloses the entire formula of the ion with charge +3. This is strictly optional; a chemical formula is valid with or without ionization information, and Hexamminecobalt(III) chloride may be written as [Co(NH)]Cl or [Co(NH)]Cl. Brackets, like parentheses, behave in chemistry as they do in mathematics, grouping terms together they are not specifically employed only for ionization states. In the latter case here, the parentheses indicate 6

title: Atmospheric methane

text: decomposition; during which time very little methane is produced. However, generally within a year oxygen levels are depleted and anaerobic conditions dominate the landfill allowing methanogens to takeover the decomposition process. These methanogens emit methane into the atmosphere and even after the landfill is closed, the mass amount of decaying matter allows the methanogens to continue producing methane for years. Waste water treatment facilities act to remove organic matter, solids, pathogens, and chemical hazards as a result of human contamination. Methane emission in waste treatment facilities occurs as a result of anaerobic treatments of organic compounds and anaerobic biodegradation of

title: Methane

text: which the halogen atom abstracts a hydrogen atom from a methane molecule, resulting in the formation of a hydrogen halide molecule and a methyl radical (CH•). The methyl radical then reacts with a molecule of the halogen to form a molecule of the halomethane, with a new halogen atom as byproduct. Similar reactions can occur on the halogenated product, leading to replacement of additional hydrogen atoms by halogen atoms with dihalomethane, trihalomethane, and ultimately, tetrahalomethane structures, depending upon reaction conditions and the halogen-to-methane ratio. Methane is used in industrial chemical processes and may be transported as a refrigerated liquid (liquefied

title: Methane chimney

text: chimneys do not produce such visible signs at the sea surface. Instead, plumes are identified by a combination of chemical and physical oceanographic and geologic data. Plumes of methane bubbles, whether in the water column or subseafloor sediments, have lower density and sound speed than the surrounding water. As such, these plumes can be imaged by a variety of acoustic techniques, including seismic reflection data and conventional fishfinders. Dissolved methane is usually identified through widespread chemical analysis of water samples, including gas chromatography of gasses extracted from the headspace of seawater samples taken at depth (headspace is the space above

title: Bis(diphenylphosphino)methane

text: is even more acidic in these derivatives. As a chelating ligand, 1,1-bis(diphenylphosphino)methane forms a four-membered ring with the constituents MPC. The ligand promotes the formation of bimetallic complexes that feature five-membered MPC rings. In this way, dppm promotes the formation of bimetallic complexes. One such example is the dipalladium chloride, PdCl(dppm). In this complex, the oxidation state for the Pd centres are I. Bis(diphenylphosphino)methane gives rise to a family of coordination compounds known as A-frame complexes. Bis(diphenylphosphino)methane 1,1-Bis(diphenylphosphino)methane (dppm), is an organophosphorus compound with the formula CH(PPh). Dppm, a white, crystalline powder, is used in inorganic and organometallic chemistry as

title: Chemical formula

text: groups all of the same shape, bonded to another group of size 1 (the cobalt atom), and then the entire bundle, as a group, is bonded to 3 chlorine atoms. In the former case, it is clearer that the bond connecting the chlorines is ionic, rather than covalent. Although isotopes are more relevant to nuclear chemistry or stable isotope chemistry than to conventional chemistry, different isotopes may be indicated with a prefixed superscript in a chemical formula. For example, the phosphate ion containing radioactive phosphorus-32 is [PO]. Also a study involving stable isotope ratios might include the molecule OO. A

title: Bis(diphenylphosphino)methane

text: Bis(diphenylphosphino)methane 1,1-Bis(diphenylphosphino)methane (dppm), is an organophosphorus compound with the formula CH(PPh). Dppm, a white, crystalline powder, is used in inorganic and organometallic chemistry as a ligand. It is more specifically a chelating ligand because it is a ligand that can bond to metals with two phosphorus donor atoms. The natural bite angle is 73°. 1,1-Bis(diphenylphosphino)methane was first prepared by the reaction of sodium diphenylphosphide (PhPNa) with dichloromethane: The methylene group (CH) in dppm (and especially its complexes) is mildly acidic. The ligand can be oxidized to give the corresponding oxides and sulfides CH[P(E)Ph] (E = O, S). The methylene group

title: Oxidative coupling of methane

text: radical process. Nevertheless, some recent work have shown that the mechanism of the OCM could be initiated by an heterolytic cleavage of the C-H bond on magnesium oxide in the presence of atmosphere. Eventually, the inability to discover a selective catalyst led to a gradual loss of interest in OCM. Beginning in the mid-1990s, research activity in this area began to decline significantly, as evidenced by the decreasing number of patents filed and peer-reviewed publications. Oxidative coupling of methane The oxidative coupling of methane (OCM) is a type of chemical reaction discovered in the 1980s for the direct conversion of

title: Methane clumped isotopes

text: to a wide range of observed "formula_21" and "formula_22" values, which has the potential to provide insights into methanogenesis rate and chemical condition in the corresponding environments. Methane clumped isotopes Methane clumped isotopes are methane molecules that contain two or more rare isotopes. Methane (CH) contains two elements, carbon and hydrogen, each of which has two stable isotopes. For carbon, 98.9% are in the form of carbon-12 (C) and 1.1% are carbon-13 (C); while for hydrogen, 99.99% are in the form of protium (H) and 0.01% are deuterium (H or D). Carbon-13 (C) and deuterium (H or D) are rare

title: Aerobic methane production

text: theorized that "the structural component pectin plays a prominent role in the in situ formation of CH in plants" but were unable to identify a chemical mechanism for this CH production. Wang "et al." (2008) found that methane emissions varied greatly by plant species, noting that shrub species were much more likely to produce methane than herbaceous species. They also noted that among herbaceous species which they tested, those that emitted methane did so from stems, but not from detached leaves, while shrub species typically emitted higher methane concentrations from detached leaves. A follow-up study by Keppler "et al." reconfirmed

title: Methane

text: alcohol. The chemical suffix ""-ane"" is from the coordinating chemical suffix ""-ine"" which is from Latin feminine suffix ""-ina"" which is applied to represent abstracts. The coordination of "-ane", "-ene", "-one", etc. was proposed in 1866 by German chemist August Wilhelm von Hofmann (1818-1892). Methane is a tetrahedral molecule with four equivalent C–H bonds. Its electronic structure is described by four bonding molecular orbitals (MOs) resulting from the overlap of the valence orbitals on C and H. The lowest energy MO is the result of the overlap of the 2s orbital on carbon with the in-phase combination of the 1s

title: Methane clathrate

text: creates carbon emissions. Methane clathrates (hydrates) are also commonly formed during natural gas production operations, when liquid water is condensed in the presence of methane at high pressure. It is known that larger hydrocarbon molecules like ethane and propane can also form hydrates, although longer molecules (butanes, pentanes) cannot fit into the water cage structure and tend to destabilise the formation of hydrates. Once formed, hydrates can block pipeline and processing equipment. They are generally then removed by reducing the pressure, heating them, or dissolving them by chemical means (methanol is commonly used). Care must be taken to ensure that

title: Chemical cycling

text: important role in sustaining the biosphere. Notable active chemical cycles on Earth include: Other chemical cycles include hydrogen peroxide. Recent evidence suggests that similar chemical cycles to Earth's occur on a lesser scale on Mars, facilitated by the thin atmosphere, including carbon dioxide (and possibly carbon), water, sulphur, methane, oxygen, ozone, and nitrogen cycles. Many studies point to significantly more active chemical cycles on Mars in the past, however the faint young Sun paradox has proved problematic in determining chemical cycles involved in early climate models of the planet. Jupiter, like all the gas giants, has an atmospheric methane cycle.

title: Chemical looping reforming and gasification

text: This chemical looping process was advanced to the commercial level. Its commercial operation, however, was hampered in part by the inadequacies in the chemical and mechanical viability of the oxygen carrier VPO and its associated effects on the reaction kinetics of the particles. Chemical looping selective oxidation was also applied to the production of olefins from methane. In chemical looping oxidative coupling of methane (OCM), the oxygen carrier selectively converts methane into ethylene. Chemical looping reforming and gasification Chemical looping reforming (CLR) and gasification (CLG) are the operations that involve the use of gaseous carbonaceous feedstock and solid carbonaceous feedstock,

title: Chemical cycling

text: oxygen cycles on Ganymede and oxygen and radiolytic carbon dioxide cycles on Callisto. In addition to Saturn's methane cycle some studies suggest an ammonia cycle induced by photolysis similar to Jupiter's. The cycles of its moons are of particular interest. Observations by Cassini–Huygens of Titan's atmosphere and interactions with its liquid mantle give rise to several active chemical cycles including a methane, hydrocarbon, hydrogen, and carbon cycles. Enceladus has an active hydrological, silicate and possibly a nitrogen cycle. Uranus has an active methane cycle. Methane is converted to hydrocarbons through photolysis which condenses and as they are heated, release methane

title: Methane clumped isotopes

text: that have the same chemical composition, but differ only in their isotopic composition. Methane has ten stable isotopologues: CH, CH, CHD, CHD, CHD, CHD, CHD, CHD, CD and CD, among which, CH is an unsubstituted isotopologue; CH and CHD are singly substituted isotopologues; CHD and CHD are doubly substituted isotopologues. The multiple-substituted isotopologues are clumped isotopologues. The absolute abundance of each isotopologue primarily depends on the traditional carbon and hydrogen isotope compositions ("δ"C and "δ"D) of the molecules. Clumped isotope composition is calculated relative to the random distribution of carbon and hydrogen isotopes in the methane molecules. The deviations from

title: Bohr model of the chemical bond

text: achieved through the balance of forces between the forces of attraction of nuclei to the plane of the ring of electrons and the forces of mutual repulsion of the nuclei. The Bohr model of the chemical bond took into account the Coulomb repulsion - the electrons in the ring are at the maximum distance from each other. Thus, according to this model, the methane molecule is a regular tetrahedron, in which center the carbon nucleus locates, and in the corners - the nucleus of hydrogen. Chemical bond between them form four two-electron rings, rotating around the lines connecting the center

title: Sulfate-methane transition zone

text: a significant difference between the microbial diversity within and under the SMTZ. It is still difficult to broadly name microbial communities found in all SMTZs because dominant groups are determined by ecological and chemical factors. However, it has been observed that the richness in species is relatively similar across SMTZ horizons, especially within the "Deltaproteobacteria". The diversity of archaea and bacteria in the SMTZ vary with depth, but bacteria tend to have richer diversity than the archaea. The SMTZ is a major sink for methane because AOM consumes mostly all of the methane produced by methanogens. It has been shown

title: Chemical composition

text: Chemical composition Chemical composition refers to the identity and relative number of the chemical elements that make up any particular compound. The chemical composition of a pure substance corresponds to the relative amounts of the elements that constitute the substance itself. It can be expressed with a chemical formula, such as an empirical or molecular formula. For example, the chemical formula for water is HO: this means that each molecule of water is constituted by 2 atoms of hydrogen (H) and 1 atom of oxygen (O). Thus the chemical composition of water may be interpreted as a 2:1 ratio of

title: Methane

text: the oxidant, the anaerobic oxidation of methane. Methane is nontoxic, yet it is extremely flammable and may form explosive mixtures with air. Methane is also an asphyxiant if the oxygen concentration is reduced to below about 16% by displacement, as most people can tolerate a reduction from 21% to 16% without ill effects. The concentration of methane at which asphyxiation risk becomes significant is much higher than the 5–15% concentration in a flammable or explosive mixture. Methane off-gas can penetrate the interiors of buildings near landfills and expose occupants to significant levels of methane. Some buildings have specially engineered recovery

title: Structural formula

text: Structural formula The structural formula of a chemical compound is a graphic representation of the molecular structure, showing how the atoms are arranged. The chemical bonding within the molecule is also shown, either explicitly or implicitly. Unlike chemical formulas, which have a limited number of symbols and are capable of only limited descriptive power, structural formulas provide a complete geometric representation of the molecular structure. For example, many chemical compounds exist in different isomeric forms, which have different enantiomeric structures but the same chemical formula. A structural formula is able to indicate arrangements of atoms in three-dimensional space in a

title: Methane

text: floors of Earth at large depths. Estimates consider up to 15,000 gigatonnes of carbon may be stored in the form of clathrates (hydrates) in the ocean floor, not accounting for abiotic methane, a relatively newly discovered source of methane, formed below the ocean floor, in the earth crust. It has been suggested, that today's methane emission regime from the ocean floor, is potentially similar to that during the PETM. Arctic methane release from permafrost and methane clathrates is an expected consequence and further cause of global warming. There is a group of bacteria that drive methane oxidation with nitrite as

title: Methane

text: Apart from gas fields, an alternative method of obtaining methane is via biogas generated by the fermentation of organic matter including manure, wastewater sludge, municipal solid waste (including landfills), or any other biodegradable feedstock, under anaerobic conditions. Rice fields also generate large amounts of methane during plant growth. Methane hydrates/clathrates (ice-like combinations of methane and water on the sea floor, found in vast quantities) are a potential future source of methane. Cattle belch methane accounts for 16% of the world's annual methane emissions to the atmosphere. One study reported that the livestock sector in general (primarily cattle, chickens, and pigs)

title: Methane

text: also subjected to free-radical chlorination in the production of chloromethanes, although methanol is a more typical precursor. There are two main routes for geological methane generation, organic (thermogenic), and inorganic (abiotic, meaning non-living). Thermally generated methane, referred to as thermogenic, originates from deeper sedimentary strata. Thermogenic methane (CH) formation occurs due to the breakup of organic matter, forced by elevated temperatures and pressures. This type of methane is considered to be the primary methane type in sedimentary basins, and from an economical perspective the most important source of natural gas. Thermogenic methane components are generally considered to be relic (from

title: Anaerobic oxidation of methane

text: gas methane from the ocean into the atmosphere. It is estimated that almost 80% of all the methane that arises from marine sediments is oxidized anaerobically by this process. Anaerobic oxidation of methane Anaerobic oxidation of methane (AOM) is a microbial process occurring in anoxic marine and freshwater sediments. During AOM methane is oxidized with different terminal electron acceptors such as sulfate, nitrate, nitrite and metals. The overall reaction is: Sulfate-driven AOM is mediated by a syntrophic consortium of methanotrophic archaea and sulfate-reducing bacteria. They often form small aggregates or sometimes voluminous mats. The archaeal partner is abbreviated ANME, which

title: Methane

text: not acceptable. Methane can be produced by protonation of methyl lithium and methylmagnesium iodide. In practice, a requirement for pure methane will be filled with a steel gas bottle from standard suppliers. Methane was discovered and isolated by Alessandro Volta between 1776 and 1778 when studying marsh gas from Lake Maggiore. It is the major component of natural gas, about 87% by volume. The major source of methane is extraction from geological deposits known as natural gas fields, with coal seam gas extraction becoming a major source (see Coal bed methane extraction, a method for extracting methane from a coal

title: Empirical formula

text: Empirical formula In chemistry, the empirical formula of a chemical compound is the simplest positive integer ratio of atoms present in a compound. A simple example of this concept is that the empirical formula of sulphur monoxide, or SO, would simply be SO, as is the empirical formula of disulfur dioxide, SO. This means that sulfur monoxide and disulfur dioxide, both compounds of sulfur and oxygen, will have the same empirical formula. However, their chemical formulas, which express the number of atoms in each molecule of a chemical compound, may not be the same. An empirical formula makes no mention

title: Chemical compound

text: of atoms (chemical elements) in a fixed stoichiometric proportion can be termed a "chemical compound"; the concept is most readily understood when considering pure chemical substances. It follows from their being composed of fixed proportions of two or more types of atoms that chemical compounds can be converted, via chemical reaction, into compounds or substances each having fewer atoms. The ratio of each element in the compound is expressed in a ratio in its chemical formula. A chemical formula is a way of expressing information about the proportions of atoms that constitute a particular chemical compound, using the standard abbreviations

title: Methane

text: deposit, while enhanced coal bed methane recovery is a method of recovering methane from non-mineable coal seams). It is associated with other hydrocarbon fuels, and sometimes accompanied by helium and nitrogen. Methane is produced at shallow levels (low pressure) by anaerobic decay of organic matter and reworked methane from deep under the Earth's surface. In general, the sediments that generate natural gas are buried deeper and at higher temperatures than those that contain oil. Methane is generally transported in bulk by pipeline in its natural gas form, or LNG carriers in its liquefied form; few countries transport it by truck.

title: Methane

text: an earlier time). Generally, formation of thermogenic methane (at depth) can occur through organic matter breakup, or organic synthesis. Both ways can involve microorganisms (methanogenesis) but may also occur inorganically. The involved anaerobic and aerobic processes can also consume methane, with and without microorganisms. The more important source of methane at depth (crystalline bedrock) is abiotic. Abiotic means that the methane formation took place involving inorganic compounds, without biological activity, magmatic or created at low temperatures and pressures through water-rock reactions. Naturally occurring methane is mainly produced by microbial methanogenesis. This multistep process is used by microorganisms as an energy

title: Abundance of the chemical elements

text: in the Sun and outer planets is similar to that in the universe. Due to solar heating, the elements of Earth and the inner rocky planets of the Solar System have undergone an additional depletion of volatile hydrogen, helium, neon, nitrogen, and carbon (which volatilizes as methane). The crust, mantle, and core of the Earth show evidence of chemical segregation plus some sequestration by density. Lighter silicates of aluminum are found in the crust, with more magnesium silicate in the mantle, while metallic iron and nickel compose the core. The abundance of elements in specialized environments, such as atmospheres, or

title: Methane

text: source. The net reaction is The final step in the process is catalyzed by the enzyme Coenzyme-B sulfoethylthiotransferase. Methanogenesis is a form of anaerobic respiration used by organisms that occupy landfill, ruminants (for example cows or cattle), and the guts of termites. It is uncertain whether plants are a source of methane emissions. There are many technological methane production methods. However, as methane is the main component in natural gas and a major energy source, there is little industrial incentive to prepare it from other sources, although some plants use coal to gas processes (see below). Methane created from biomass

title: Atmospheric methane

text: fill in the gaps of previous global methane budgets as well as explain large plumes of methane that have been observed over the tropics. In wetlands, where the rate of methane production is high, plants help methane travel into the atmosphere—acting like inverted lightning rods as they direct the gas up through the soil and into the air. They are also suspected to produce methane themselves, but because the plants would have to use aerobic conditions to produce methane, the process itself is still unidentified. At high pressures, such as are found on the bottom of the ocean, methane forms

title: Atmospheric methane

text: of carbon in methane oxidation. Methane oxidation allows methanotrophic bacteria to use methane as a source of energy, reacting methane with oxygen and as a result producing carbon dioxide and water. The most effective sink of atmospheric methane is the hydroxyl radical in the troposphere, or the lowest portion of Earth’s atmosphere. As methane rises into the air, it reacts with the hydroxyl radical to create water vapor and carbon dioxide. The lifespan of methane in the atmosphere was estimated at 9.6 years as of 2001; however, increasing emissions of methane over time reduce the concentration of the hydroxyl radical

title: Oxidative coupling of methane

text: on the mechanism of methane activation, which is a radical mechanism, forming H and CH3 radicals by the homolytic cleavage of the C-H bond. Ethylene and ethane that are proposed products have C-H bonds of similar strength. Thus, any catalyst that can activate methane can also activate the products. The yield of ethylene (and/or ethane) is limited by the relative rates of the methane and ethylene reactions, and these rates are very similar. Reactions of the products lead to higher homologues, and eventually to aromatics and coke. The same limitation applies to direct pyrolysis of methane, which is also a

title: Methane

text: internal parts of rocket motors, reducing the difficulty of re-use of boosters. Methane is abundant in many parts of the Solar system and potentially could be harvested on the surface of another solar-system body (in particular, using methane production from local materials found on Mars or Titan), providing fuel for a return journey. Natural gas, which is mostly composed of methane, is used to produce hydrogen gas on an industrial scale. Steam Methane Reforming, or SMR, is the most common method of producing commercial bulk hydrogen gas. More than 50 million metric tons are produced annually worldwide (2013), principally from

title: Methane

text: in catalysts that facilitate C–H bond activation in methane (and other lower numbered alkanes). Methane's heat of combustion is 55.5 MJ/kg. Combustion of methane is a multiple step reaction summarized as follows: Peters four-step chemistry is a systematically reduced four-step chemistry which explains the burning of methane. Given appropriate conditions, methane reacts with as follows: where X is a halogen: fluorine (F), chlorine (Cl), bromine (Br), or iodine (I). This mechanism for this process is called free radical halogenation. It is initiated when UV light or some other radical initiator produces a halogen atom. A two-step chain reaction ensues in

title: Coalbed methane

text: Coalbed methane Coalbed methane (CBM or coal-bed methane), coalbed gas, coal seam gas (CSG), or coal-mine methane (CMM) is a form of natural gas extracted from coal beds. In recent decades it has become an important source of energy in United States, Canada, Australia, and other countries. The term refers to methane adsorbed into the solid matrix of the coal. It is called 'sweet gas' because of its lack of hydrogen sulfide. The presence of this gas is well known from its occurrence in underground coal mining, where it presents a serious safety risk. Coalbed methane is distinct from a

title: Atmospheric methane

text: order of parts per trillion. Atmospheric methane Atmospheric methane is the methane present in Earth's atmosphere. Atmospheric methane concentrations are of interest because it is one of the most potent greenhouse gases in Earth's atmosphere. The 100-year global warming potential of methane is 28. That is, over a 100-year period, it traps 28 times more heat per mass unit than carbon dioxide and 32 times the effect when accounting for aerosol interactions. Global methane concentrations had risen from 722 parts per billion (ppb) in pre-industrial times to 1800 ppb by 2011, an increase by a factor of 2.5 and the

title: Atmospheric methane

text: Atmospheric methane Atmospheric methane is the methane present in Earth's atmosphere. Atmospheric methane concentrations are of interest because it is one of the most potent greenhouse gases in Earth's atmosphere. The 100-year global warming potential of methane is 28. That is, over a 100-year period, it traps 28 times more heat per mass unit than carbon dioxide and 32 times the effect when accounting for aerosol interactions. Global methane concentrations had risen from 722 parts per billion (ppb) in pre-industrial times to 1800 ppb by 2011, an increase by a factor of 2.5 and the highest value in at least

title: Atmospheric methane

text: in the atmosphere. With less OH˚ to react with, the lifespan of methane could also increase, resulting in greater concentrations of atmospheric methane. If it is not destroyed in the troposphere, methane will last approximately 120 years before it is eventually destroyed in Earth’s next atmospheric layer: the stratosphere. Destruction in the stratosphere occurs the same way that it does in the troposphere: methane is oxidized to produce carbon dioxide and water vapor. Based on balloon-borne measurements since 1978, the abundance of stratospheric methane has increased by between 1978 and 2003. The reaction of methane and chlorine atoms acts as

title: Methane

text: cannot be deprotonated in solution, but the conjugate base is known in forms such as methyllithium. A variety of positive ions derived from methane have been observed, mostly as unstable species in low-pressure gas mixtures. These include methenium or methyl cation , methane cation , and methanium or protonated methane . Some of these have been detected in outer space. Methanium can also be produced as diluted solutions from methane with superacids. Cations with higher charge, such as and , have been studied theoretically and conjectured to be stable. Despite the strength of its C–H bonds, there is intense interest

title: Atmospheric methane

text: of oxygen is an aerobic source of methane. Wetlands account for approximately 20 percent of atmospheric methane through emissions from soils and plants. Wetlands counteract the sinking action that normally occurs with soil because of the high water table. The level of the water table represents the boundary between anaerobic methane production and aerobic methane consumption. When the water table is low, the methane generated within the wetland soil has to come up through the soil and get past a deeper layer of methanotrophic bacteria, thereby reducing emission. Methane transport by vascular plants can bypass this aerobic layer, thus increasing

title: Atmospheric methane

text: and carbon dioxide into methane and water. Oxygen did not become a major part of the atmosphere until photosynthetic organisms evolved later in Earth's history. With no oxygen, methane stayed in the atmosphere longer and at higher concentrations than it does today. The known sources of methane are predominantly located near the Earth's surface. In combination with vertical atmospheric motions and methane's relatively long lifetime, methane is considered to be a well-mixed gas. In other words, the concentration of methane is taken to be constant with respect to height within the troposphere. The dominant sink of methane in the troposphere

title: Methane clumped isotopes

text: the random distribution is the key signature of methane clumped isotope (please see "notation" for details). In thermodynamic equilibrium, methane clumped isotopologue composition has a monotonic relationship with formation temperature. This is the condition for many geological environments so that methane clumped isotope can record its formation temperature, and therefore can be used to identify the origins of methane. When methane clumped-isotope composition is controlled by kinetic effects, for example, for microbial methane, it has the potential to be used to study metabolism. The study of methane clumped isotopologues is very recent. The first mass spectrometry measurement of methane clumped

title: Empirical formula

text: of the arrangement or number of atoms. It is standard for many ionic compounds, like calcium chloride (CaCl), and for macromolecules, such as silicon dioxide (SiO). The molecular formula, on the other hand, shows the number of each type of atom in a molecule. The structural formula shows the arrangement of the molecule. It is also possible for different types of compounds to have equal empirical formulas. Samples are analyzed in specific elemental analysis tests to determine what percent of a particular element the sample is composed of. A chemical analysis of a sample of methyl acetate provides the following

title: Formula

text: often algebraic, closed form, and/or analytical. In modern chemistry, a chemical formula is a way of expressing information about the proportions of atoms that constitute a particular chemical compound, using a single line of chemical element symbols, numbers, and sometimes other symbols, such as parentheses, brackets, and plus (+) and minus (−) signs. For example, HO is the chemical formula for water, specifying that each molecule consists of two hydrogen (H) atoms and one oxygen (O) atom. Similarly, O denotes an ozone molecule consisting of three oxygen atoms and having a net negative charge. In a general context, formulas are

title: Coalbed methane in the United States

text: At least of it is economically viable to produce. Coalbed methane grew out of venting methane from coal seams. Some coal beds have long been known to be "gassy," and as a safety measure, boreholes were drilled into the seams from the surface, and the methane allowed to vent before mining. Methane produced in connection with coal mining is usually called "coal mine methane." Coalbed methane received a major push from the US federal government in the late 1970s. Federal price controls were discouraging natural gas drilling by keeping natural gas prices below market levels; at the same time, the

title: Coalbed methane extraction

text: Coalbed methane extraction Coalbed methane extraction (CBM extraction) is a method for extracting methane from a coal deposit. Methane adsorbed into a solid coal matrix (coal macerals) will be released if the coal seam is depressurised. Methane may be extracted by drilling wells into the coal seam. The goal is to decrease the water pressure by pumping water from the well. The decrease in pressure allows methane to desorb from the coal and flow as a gas up the well to the surface. Methane is then compressed and piped to market. The objective is to avoid putting methane into the

title: Structural formula

text: same chemical compound. Another example is formal double bonds where the electron density is spread outside the formal bond, leading to partial double bond character and slow inter-conversion at room temperature. For all dynamic effects, temperature will affect the inter-conversion rates and may change how the structure should be represented. There is no explicit temperature associated with a structural formula, although many assume that it would be standard temperature. Structural formula The structural formula of a chemical compound is a graphic representation of the molecular structure, showing how the atoms are arranged. The chemical bonding within the molecule is also

title: Atmospheric methane

text: source of methane, possibly being responsible for approximately 10 to 30 percent of atmospheric methane. A 2006 paper calculated emissions of 62–236 Tg a, and "this newly identified source may have important implications". However the authors stress ""our findings are preliminary with regard to the methane emission strength"". These findings have been called into question in a 2007 paper which found ""there is no evidence for substantial aerobic methane emission by terrestrial plants, maximally 0.3% of the previously published values"". While the details of plant methane emissions have yet to be confirmed, plants as a significant methane source would help

title: Methane clathrate

text: 46 water molecules per unit cell.) This compares with a hydration number of 20 for methane in aqueous solution. A methane clathrate MAS NMR spectrum recorded at 275 K and 3.1 MPa shows a peak for each cage type and a separate peak for gas phase methane. In 2003, a clay-methane hydrate intercalate was synthesized in which a methane hydrate complex was introduced at the interlayer of a sodium-rich montmorillonite clay. The upper temperature stability of this phase is similar to that of structure I hydrate. Methane clathrates are restricted to the shallow lithosphere (i.e. < 2,000 m depth). Furthermore,

title: Methane clathrate

text: marine geosphere and they occur in deep sedimentary structures and form outcrops on the ocean floor. Methane hydrates are believed to form by the precipitation or crystallisation of methane migrating from deep along geological faults. Precipitation occurs when the methane comes in contact with water within the sea bed subject to temperature and pressure. In 2008, research on Antarctic Vostok and EPICA Dome C ice cores revealed that methane clathrates were also present in deep Antarctic ice cores and record a history of atmospheric methane concentrations, dating to 800,000 years ago. The ice-core methane clathrate record is a primary source

title: Atmospheric methane

text: Most ecological emissions of methane relate directly to methanogens generating methane in warm, moist soils as well as in the digestive tracts of certain animals. Methanogens are methane producing microorganisms. In order to produce energy, they use an anaerobic process called methanogenesis. This process is used in lieu of aerobic, or with oxygen, processes because methanogens are unable to metabolise in the presence of even small concentrations of oxygen. When acetate is broken down in methanogenesis, the result is the release of methane into the surrounding environment. "Methanogenesis", the scientific term for methane production, occurs primarily in anaerobic conditions because

title: Methane clathrate

text: depth or close to the sediment-water interface. They may cap even larger deposits of gaseous methane. There are two distinct types of oceanic deposit. The most common is dominated (> 99%) by methane contained in a structure I clathrate and generally found at depth in the sediment. Here, the methane is isotopically light (δC < −60‰), which indicates that it is derived from the microbial reduction of CO. The clathrates in these deep deposits are thought to have formed in situ from the microbially produced methane, since the δC values of clathrate and surrounding dissolved methane are similar. However, it

title: Atmospheric methane

text: is produced photochemically in the atmosphere. Production of this radical is not fully understood and has a large effect on atmospheric concentrations. This uncertainty is exemplified by observations that have shown between the year 2000 and 2006 increases in atmospheric concentration of methane ceased, for reasons still being investigated. Various sources give the following values for methane emissions: Any process that results in the production of methane and its release into the atmosphere can be considered a "source." The two main processes that are responsible for methane production occur as a result of microorganisms anaerobically converting organic compounds into methane.

title: Arctic methane emissions

text: the water temperature. Arctic methane emissions Arctic methane release is the release of methane from seas and soils in permafrost regions of the Arctic. While a long-term natural process, it is exacerbated by global warming. This results in a positive feedback effect, as methane is itself a powerful greenhouse gas. The Arctic region is one of the many natural sources of the greenhouse gas methane. Global warming accelerates its release, due to both release of methane from existing stores, and from methanogenesis in rotting biomass. Large quantities of methane are stored in the Arctic in natural gas deposits, permafrost, and

title: Arctic methane emissions

text: Arctic methane emissions Arctic methane release is the release of methane from seas and soils in permafrost regions of the Arctic. While a long-term natural process, it is exacerbated by global warming. This results in a positive feedback effect, as methane is itself a powerful greenhouse gas. The Arctic region is one of the many natural sources of the greenhouse gas methane. Global warming accelerates its release, due to both release of methane from existing stores, and from methanogenesis in rotting biomass. Large quantities of methane are stored in the Arctic in natural gas deposits, permafrost, and as undersea clathrates.

title: Atmospheric methane

text: a solid clathrate with water, known as methane hydrate. An unknown, but possibly very large quantity of methane is trapped in this form in ocean sediments. The release of large volumes of methane gas from such sediments into the atmosphere has been suggested as a possible cause for rapid global warming events in the Earth's distant past, such as the Paleocene–Eocene Thermal Maximum of 55 million years ago, and the Great Dying. Theories suggest that should global warming cause them to heat up sufficiently, all of this methane gas could again be released into the atmosphere. Since methane gas is

title: Coalbed methane

text: estimated to be 2,900 billion cubic meters, it may be that as little as one percent might be economically recoverable. Britain's CBM potential is largely untested. Some methane is extracted by coal mine venting operations, and burned to generate electricity. Assessment by private industry of coalbed methane wells independent of mining began in 2008, when 55 onshore exploration licences were issued, covering 7,000 square kilometers of potential coalbed methane areas. IGas Energy became the first in the UK to commercially extract coalbed methane separate from mine venting; as of 2012, the Igas coalbed methane wells at Doe Green, extracting gas

title: Coalbed methane

text: approved.Essar is also producing and investing in CBM. Prashant Modi, President and Chief Operating Officer of GEECL, said, "We are proud to be India’s first private sector company that has ventured into Coal Bed Methane exploration, production, marketing and distribution. With the nation requiring higher energy sources to sustain its development pace, we are confident that CBM will play an important role as one of the prime energy source for the future generations." Coalbed methane Coalbed methane (CBM or coal-bed methane), coalbed gas, coal seam gas (CSG), or coal-mine methane (CMM) is a form of natural gas extracted from coal

title: Coalbed methane

text: typical sandstone or other conventional gas reservoir, as the methane is stored within the coal by a process called adsorption. The methane is in a near-liquid state, lining the inside of pores within the coal (called the matrix). The open fractures in the coal (called the cleats) can also contain free gas or can be saturated with water. Unlike much natural gas from conventional reservoirs, coalbed methane contains very little heavier hydrocarbons such as propane or butane, and no natural-gas condensate. It often contains up to a few percent carbon dioxide. Coalbed methane grew out of venting methane from coal

title: Atmospheric methane

text: methane because soils are optimally moist for methanotroph activity, and the movement of gases between soil and atmosphere (soil diffusivity) is high. With a lower water table, any methane in the soil has to make it past the methanotrophic bacteria before it can reach the atmosphere. Wetland soils, however, are often sources of atmospheric methane rather than sinks because the water table is much higher, and the methane can be diffused fairly easily into the air without having to compete with the soil’s methanotrophs. "Methanotrophic bacteria in soils" – Methanotrophic bacteria that reside within soil use methane as a source

title: Anaerobic oxidation of methane

text: Anaerobic oxidation of methane Anaerobic oxidation of methane (AOM) is a microbial process occurring in anoxic marine and freshwater sediments. During AOM methane is oxidized with different terminal electron acceptors such as sulfate, nitrate, nitrite and metals. The overall reaction is: Sulfate-driven AOM is mediated by a syntrophic consortium of methanotrophic archaea and sulfate-reducing bacteria. They often form small aggregates or sometimes voluminous mats. The archaeal partner is abbreviated ANME, which stands for "anaerobic methanotroph". ANME's are very closely related to methanogenic archaea and recent investigations suggest that AOM is an enzymatic reversal of methanogenesis. It is still poorly understood

title: Methane functionalization

text: being done to further improve yields. Methane functionalization Methane functionalization is the process of converting methane in its gaseous state to another molecule with a functional group, typically methanol or acetic acid, through the use of transition metal catalysts. In the realm of carbon-hydrogen bond activation and functionalization (C-H activation/functionalization), many recent efforts have been made in order to catalytically functionalize the C-H bonds in methane. The large abundance of methane in natural gas or shale gas deposits presents a large potential for its use as a feedstock in modern chemistry. However, given its gaseous natural state, it is quite

title: Methane functionalization

text: Methane functionalization Methane functionalization is the process of converting methane in its gaseous state to another molecule with a functional group, typically methanol or acetic acid, through the use of transition metal catalysts. In the realm of carbon-hydrogen bond activation and functionalization (C-H activation/functionalization), many recent efforts have been made in order to catalytically functionalize the C-H bonds in methane. The large abundance of methane in natural gas or shale gas deposits presents a large potential for its use as a feedstock in modern chemistry. However, given its gaseous natural state, it is quite difficult to transport economically. Its ideal

title: Chemical formula

text: number of repeating units is unknown or variable, the letter "n" may be used to indicate this formula: CH(CH)CH. For ions, the charge on a particular atom may be denoted with a right-hand superscript. For example, Na, or Cu. The total charge on a charged molecule or a polyatomic ion may also be shown in this way. For example: HO or SO. Note that + and - are used in place of +1 and -1, respectively. For more complex ions, brackets [ ] are often used to enclose the ionic formula, as in [BH], which is found in compounds such

title: Methane

text: it is usually known as natural gas, which is considered to have an energy content of 39 megajoules per cubic meter, or 1,000 BTU per standard cubic foot. Methane in the form of compressed natural gas is used as a vehicle fuel and is claimed to be more environmentally friendly than other fossil fuels such as gasoline/petrol and diesel. Research into adsorption methods of methane storage for use as an automotive fuel has been conducted. Liquefied natural gas (LNG) is natural gas (predominantly methane, CH) converted into liquid form for ease of storage or transport. Liquefied natural gas occupies about

title: Wetland methane emissions

text: is in turn affected by the other controlling factors of methane in the environment. Additionally, pathways of methane emission affect how the methane travels into the atmosphere and thus have an equal effect on methane flux in wetlands. The first controlling factor to consider is the level of the water table. Not only does pool and water table location determine the areas where methane production or oxidation may take place, but it also determines how quickly methane can diffuse into the air. When traveling through water, the methane molecules run into the quickly moving water molecules and thus take a