Methanol, also known as methyl alcohol among others, is a chemical with the formula CH3OH (a methyl group linked to a hydroxyl group, often abbreviated MeOH). Methanol acquired the name wood alcohol because it was once produced chiefly by the destructive distillation of wood. Today, methanol is mainly produced industrially by hydrogenation of carbon monoxide.
Methanol is the simplest alcohol, consisting of a methyl group linked to a hydroxyl group. It is a light, volatile, colorless, flammable liquid with a distinctive odor similar to that of ethanol (drinking alcohol). Methanol is however far more toxic than ethanol. At room temperature, it is a polar liquid. With more than 20 million tons produced annually, it is used as a precursor to other commodity chemicals, including formaldehyde, acetic acid, methyl tert-butyl ether, as well as a host of more specialized chemicals.
|Preferred IUPAC name
3D model (JSmol)
3OH or CH
|Molar mass||32.04 g mol−1|
|Melting point||−97.6 °C (−143.7 °F; 175.6 K)|
|Boiling point||64.7 °C (148.5 °F; 337.8 K)|
|Vapor pressure||13.02 kPa (at 20 °C)|
Refractive index (nD)
|Viscosity||0.545 mPa·s (at 25 °C) |
|Main hazards||Moderately Toxic for small animals – Highly Toxic to large animals and humans — May be fatal/lethal or cause blindness and damage to the liver, kidneys, and heart if swallowed – Toxic effects from repeated over exposure have an accumulative effect on the central nervous system, especially the optic nerve – Symptoms may be delayed, become severe after 12 to 18 hours, and linger for several days after exposure |
|Safety data sheet||See: data page|
|GHS signal word||Danger |
|H225, H301, H311, H331, H370|
|P210, P233, P240, P241, P242, P243, P260, P264, P270, P271, P280, P301+330+331, P310, P302+352, P312, P303+361+353, P304+340, P311, P305+351+338, P307+311, P337+313, P361, P363, P370+378, P403+233|
|Flash point||11 to 12 °C (52 to 54 °F; 284 to 285 K)|
| 470 °C (878 °F; 743 K)|
385 °C (725 °F; 658 K)
|Lethal dose or concentration (LD, LC):|
LD50 (median dose)
|5628 mg/kg (rat, oral)|
7300 mg/kg (mouse, oral)
12880 mg/kg (rat, oral)
14200 mg/kg (rabbit, oral)
LC50 (median concentration)
|64,000 ppm (rat, 4 h)|
LCLo (lowest published)
|33,082 ppm (cat, 6 h)|
37,594 ppm (mouse, 2 h)
|US health exposure limits (NIOSH):|
|TWA 200 ppm (260 mg/m3)|
|TWA 200 ppm (260 mg/m3) ST 250 ppm (325 mg/m3) [skin]|
IDLH (Immediate danger)
|Supplementary data page|
|Refractive index (n),|
Dielectric constant (εr), etc.
|UV, IR, NMR, MS|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Small amounts of methanol are present in normal, healthy human individuals. One study found a mean of 4.5 ppm in the exhaled breath of test subjects. The mean endogenous methanol in humans of 0.45 g/d may be metabolized from pectin found in fruit; one kilogram of apple produces up to 1.4 g methanol.
Methanol is produced naturally in the anaerobic metabolism of many varieties of bacteria and is commonly present in small amounts in the environment. As a result, the atmosphere contains a small amount of methanol vapor. Atmospheric methanol is oxidized by air in sunlight to carbon dioxide and water over the course of days.
Methanol is also found in abundant quantities in star-forming regions of space and is used in astronomy as a marker for such regions. It is detected through its spectral emission lines.
In 2006, astronomers using the MERLIN array of radio telescopes at Jodrell Bank Observatory discovered a large cloud of methanol in space, 288 million miles (463 million km) across. In 2016, astronomers detected methyl alcohol in a planet-forming disc around the young star TW Hydrae using ALMA radio telescope.
Methanol has low acute toxicity in humans but is dangerous because, together with ethanol, it is occasionally ingested in large volumes. As little as 10 mL (0.34 US fl oz) of pure methanol can cause permanent blindness by destruction of the optic nerve. 30 mL (1.0 US fl oz) is potentially fatal. The median lethal dose is 100 mL (3.4 US fl oz) (i.e. 1–2 mL/kg body weight of pure methanol). The reference dose for methanol is 2 mg/kg in a day. Toxic effects begin hours after ingestion, and antidotes can often prevent permanent damage. Because of its similarities in both appearance and odor to ethanol (the alcohol in beverages), it is difficult to differentiate between the two (such is also the case with denatured alcohol, adulterated liquors or very low quality alcoholic beverages). However, cases exist of methanol resistance, such as that of Mike Malloy who was the victim of a failed murder attempt by methanol in the early 1930s.
Methanol is toxic by two mechanisms. First, methanol can be fatal due to its CNS depressant properties in the same manner as ethanol poisoning. Second, in a process of toxication, it is metabolized to formic acid (which is present as the formate ion) via formaldehyde in a process initiated by the enzyme alcohol dehydrogenase in the liver. Methanol is converted to formaldehyde via alcohol dehydrogenase (ADH) and formaldehyde is converted to formic acid (formate) via aldehyde dehydrogenase (ALDH). The conversion to formate via ALDH proceeds completely, with no detectable formaldehyde remaining. Formate is toxic because it inhibits mitochondrial cytochrome c oxidase, causing hypoxia at the cellular level, and metabolic acidosis, among a variety of other metabolic disturbances.
Outbreaks of methanol poisoning have occurred due to contamination of drinking alcohol. This is more common in the developing world. In 2013 more than 1700 cases occurred in the United States. Those affected are often adult men. Outcomes may be good with early treatment. Toxicity to methanol was described as early as 1856.
Because of its toxic properties, methanol is frequently used as a denaturant additive for ethanol manufactured for industrial uses. This addition of methanol exempts industrial ethanol (commonly known as "denatured alcohol" or "methylated spirit") from liquor excise taxation in the US and some other countries.
Methanol is primarily converted to formaldehyde, which is widely used in many areas, especially polymers. The conversion entails oxidation:
Acetic acid can be produced from methanol.
Condensation of methanol to produce hydrocarbons and even aromatic systems is the basis of several technologies related to gas to liquids. These include methanol-to-hydrocarbons (MTH), methanol to gasoline (MTG), and methanol to olefins (MTO), and methanol to propylene (MTP). These conversions are catalyzed by zeolites as heterogeneous catalysts. The MTG process was once commercialized at Motunui in New Zealand.
The European Fuel Quality Directive allows fuel producers to blend up to 3% methanol, with an equal amount of cosolvent, with gasoline sold in Europe. China uses more than one billion gallons of methanol per year as a transportation fuel in low level blends for conventional vehicles, and high level blends in vehicles designed for methanol fuels.
Methanol is the precursor to most simple methylamines, methyl halides, and methyl ethers. Methyl esters are produced from methanol, including the transesterification of fats and production of biodiesel via transesterification.
Methanol is a promising energy carrier because, as a liquid, it is easier to store than hydrogen and natural gas. Its energy density is however low reflecting the fact that it represents partially combusted methane. Its energy density is 15.6 MJ/L, whereas ethanol's is 24 and gasoline's is 33 MJ/L.
Further advantages for methanol is its ready biodegradability and low toxicity. It does not persist in either aerobic (oxygen-present) or anaerobic (oxygen-absent) environments. The half-life for methanol in groundwater is just one to seven days, while many common gasoline components have half-lives in the hundreds of days (such as benzene at 10–730 days). Since methanol is miscible with water and biodegradable, it is unlikely to accumulate in groundwater, surface water, air or soil.
Methanol is occasionally used to fuel internal combustion engines. It burns forming carbon dioxide and water:
One problem with high concentrations of methanol in fuel is that alcohols corrode some metals, particularly aluminium. Methanol fuel has been proposed for ground transportation. The chief advantage of a methanol economy is that it could be adapted to gasoline internal combustion engines with minimum modification to the engines and to the infrastructure that delivers and stores liquid fuel. Its energy density is however only half that of gasoline, meaning that twice the volume of methanol would be required.
Methanol is a traditional denaturant for ethanol, the product being known as "denatured alcohol" or "methylated spirit". This was commonly used during the Prohibition to discourage consumption of bootlegged liquor, and ended up causing several deaths.
Methanol is used as a solvent and as an antifreeze in pipelines and windshield washer fluid. Methanol was used as an automobile coolant antifreeze in the early 1900s. As of May 2018, methanol was banned in the EU for use in windscreen washing or defrosting due to its risk of human consumption.
In some wastewater treatment plants, a small amount of methanol is added to wastewater to provide a carbon food source for the denitrifying bacteria, which convert nitrates to nitrogen gas and reduce the nitrification of sensitive aquifers.
Methanol is used as a destaining agent in polyacrylamide gel electrophoresis.
Direct-methanol fuel cells are unique in their low temperature, atmospheric pressure operation, which lets them be greatly miniaturized. This, combined with the relatively easy and safe storage and handling of methanol, may open the possibility of fuel cell-powered consumer electronics, such as laptop computers and mobile phones.
Methanol is also a widely used fuel in camping and boating stoves. Methanol burns well in an unpressurized burner, so alcohol stoves are often very simple, sometimes little more than a cup to hold fuel. This lack of complexity makes them a favorite of hikers who spend extended time in the wilderness. Similarly, the alcohol can be gelled to reduce risk of leaking or spilling, as with the brand "Sterno".
Methanol is mixed with water and injected into high performance diesel and gasoline engines for an increase of power and a decrease in intake air temperature in a process known as water methanol injection.
Carbon monoxide and hydrogen react over a catalyst to produce methanol. Today, the most widely used catalyst is a mixture of copper and zinc oxides, supported on alumina, as first used by ICI in 1966. At 5–10 MPa (50–100 atm) and 250 °C (482 °F), the reaction is characterized by high selectivity (>99.8%):
The production of synthesis gas from methane produces three moles of hydrogen for every mole of carbon monoxide, whereas the synthesis consumes only two moles of hydrogen gas per mole of carbon monoxide. One way of dealing with the excess hydrogen is to inject carbon dioxide into the methanol synthesis reactor, where it, too, reacts to form methanol according to the equation:
where the H2O byproduct is recycled via the water-gas shift reaction
This gives an overall reaction, which is the same as listed above.
The catalytic conversion of methane to methanol is effected by enzymes including methane monooxygenases. These enzymes are mixed-function oxygenases, i.e. oxygenation is coupled with production of water and NAD+.
CH4 + O2 + NADPH + H+ → CH3OH + H2O + NAD+
Both Fe- and Cu-dependent enzymes have been characterized. Intense but largely fruitless efforts have been undertaken to emulate this reactivity. Methanol is more easily oxidized than is the feedstock methane, so the reactions tend not to be selective. Some strategies exist to circumvent this problem. Examples include Shilov systems and Fe- and Cu containing zeolites. These systems do not necessarily mimick the mechanisms employed by metalloenzymes, but draw some inspiration from them. Active sites can vary substantially from those known in the enzymes. For example, a dinuclear active site is proposed in the sMMO enzyme, whereas a mononuclear iron (alpha-Oxygen) is proposed in the Fe-zeolite.
Methanol is available commercially in various purity grades. Commercial methanol is generally classified according to ASTM purity grades A and AA. Methanol for chemical use normally corresponds to Grade AA. In addition to water, typical impurities include acetone and ethanol (which are very difficult to separate by distillation). UV-vis spectroscopy is a convenient method for detecting aromatic impurities. Water content can be determined by the Karl-Fischer titration.
In their embalming process, the ancient Egyptians used a mixture of substances, including methanol, which they obtained from the pyrolysis of wood. Pure methanol, however, was first isolated in 1661 by Robert Boyle, when he produced it via the distillation of buxus (boxwood). It later became known as "pyroxylic spirit". In 1834, the French chemists Jean-Baptiste Dumas and Eugene Peligot determined its elemental composition. They also introduced the word "methylène" to organic chemistry, forming it from Greek methy = "alcoholic liquid" + hȳlē = "forest, wood, timber, material". "Methylène" designated a "radical" that was about 14% hydrogen by weight and contained one carbon atom. This would be CH2, but at the time carbon was thought to have an atomic weight only six times that of hydrogen, so they gave the formula as CH. They then called wood alcohol (l'esprit de bois) "bihydrate de méthylène" (bihydrate because they thought the formula was C4H8O4 = (CH)4(H2O)2). The term "methyl" was derived in about 1840 by back-formation from "methylene", and was then applied to describe "methyl alcohol". This was shortened to "methanol" in 1892 by the International Conference on Chemical Nomenclature. The suffix -yl, which, in organic chemistry, forms names of carbon groups, is from the word methyl.
In 1923, the German chemists Alwin Mittasch and Mathias Pier, working for Badische-Anilin & Soda-Fabrik (BASF), developed a means to convert synthesis gas (a mixture of carbon monoxide, carbon dioxide, and hydrogen) into methanol. US patent 1,569,775 (US 1569775) was applied for on 4 Sep 1924 and issued on 12 January 1926; the process used a chromium and manganese oxide catalyst with extremely vigorous conditions: pressures ranging from 50 to 220 atm, and temperatures up to 450 °C. Modern methanol production has been made more efficient through use of catalysts (commonly copper) capable of operating at lower pressures. The modern low pressure methanol (LPM) process was developed by ICI in the late 1960s US 3326956 with the technology now owned by Johnson Matthey, which is a leading licensor of methanol technology.
The use of methanol as a motor fuel received attention during the oil crises of the 1970s. By the mid-1990s, over 20,000 methanol "flexible fuel vehicles" capable of operating on methanol or gasoline were introduced in the U.S. In addition, low levels of methanol were blended in gasoline fuels sold in Europe during much of the 1980s and early-1990s. Automakers stopped building methanol FFVs by the late-1990s, switching their attention to ethanol-fueled vehicles. While the methanol FFV program was a technical success, rising methanol pricing in the mid- to late-1990s during a period of slumping gasoline pump prices diminished interest in methanol fuels.
Between the 1960s and 1980s methanol emerged as a precursor to the feedstock chemicals acetic acid and acetic anhydride. These processes include the Monsanto acetic acid synthesis, Cativa process, and Tennessee Eastman acetic anhydride process.
Methoxide is an organic anion that is the conjugate base of methanol. … It is a conjugate base of a methanol.
p. 398: 15. The alcohols and the phenols are named after the hydrocarbon from which they derive, terminated with the suffix ol (ex. pentanol, pentenol, etc.).
Acetic acid , systematically named ethanoic acid , is a colourless liquid organic compound with the chemical formula CH3COOH (also written as CH3CO2H or C2H4O2). When undiluted, it is sometimes called glacial acetic acid. Vinegar is no less than 4% acetic acid by volume, making acetic acid the main component of vinegar apart from water. Acetic acid has a distinctive sour taste and pungent smell. In addition to household vinegar, it is mainly produced as a precursor to polyvinyl acetate and cellulose acetate. It is classified as a weak acid since it only partially dissociates in solution, but concentrated acetic acid is corrosive and can attack the skin.
Acetic acid is the second simplest carboxylic acid (after formic acid). It consists of a methyl group attached to a carboxyl group. It is an important chemical reagent and industrial chemical, used primarily in the production of cellulose acetate for photographic film, polyvinyl acetate for wood glue, and synthetic fibres and fabrics. In households, diluted acetic acid is often used in descaling agents. In the food industry, acetic acid is controlled by the food additive code E260 as an acidity regulator and as a condiment. In biochemistry, the acetyl group, derived from acetic acid, is fundamental to all forms of life. When bound to coenzyme A, it is central to the metabolism of carbohydrates and fats.
The global demand for acetic acid is about 6.5 million metric tons per year (Mt/a), of which approximately 1.5 Mt/a is met by recycling; the remainder is manufactured from methanol. Vinegar is mostly dilute acetic acid, often produced by fermentation and subsequent oxidation of ethanol.Alcohol
In chemistry, an alcohol is any organic compound in which the hydroxyl functional group (–OH) is bound to a carbon. The term alcohol originally referred to the primary alcohol ethanol (ethyl alcohol), which is used as a drug and is the main alcohol present in alcoholic beverages. An important class of alcohols, of which methanol and ethanol are the simplest members, includes all compounds for which the general formula is CnH2n+1OH. It is these simple monoalcohols that are the subject of this article.
The suffix -ol appears in the IUPAC chemical name of all substances where the hydroxyl group is the functional group with the highest priority. When a higher priority group is present in the compound, the prefix hydroxy- is used in its IUPAC name. The suffix -ol in non-IUPAC names (such as paracetamol or cholesterol) also typically indicates that the substance is an alcohol. However, many substances that contain hydroxyl functional groups (particularly sugars, such as glucose and sucrose) have names which include neither the suffix -ol, nor the prefix hydroxy-.Alcohol fuel
Alcohols have been used as a fuel. The first four aliphatic alcohols (methanol, ethanol, propanol, and butanol)
are of interest as fuels because they can be synthesized chemically or biologically, and they have characteristics which allow them to be used in internal combustion engines. The general chemical formula for alcohol fuel is CnH2n+1OH.
Most methanol is produced from natural gas, although it can be produced from biomass using very similar chemical processes. Ethanol is commonly produced from biological material through fermentation processes. Biobutanol has the advantage in combustion engines in that its energy density is closer to gasoline than the simpler alcohols (while still retaining over 25% higher octane rating); however, biobutanol is currently more difficult to produce than ethanol or methanol. When obtained from biological materials and/or biological processes, they are known as bioalcohols (e.g. "bioethanol"). There is no chemical difference between biologically produced and chemically produced alcohols.
One advantage shared by the four major alcohol fuels is their high octane rating. This tends to increase their fuel efficiency and largely offsets the lower energy density of vehicular alcohol fuels (as compared to petrol/gasoline and diesel fuels), thus resulting in comparable "fuel economy" in terms of distance per volume metrics, such as kilometers per liter, or miles per gallon.Aspartame
Aspartame (APM) is an artificial non-saccharide sweetener used as a sugar substitute in some foods and beverages. In the European Union, it is codified as E951. Aspartame is a methyl ester of the aspartic acid/phenylalanine dipeptide.
A panel of experts set up by the European Food Safety Authority concluded in 2013 that aspartame is safe for human consumption at current levels of exposure. As of 2018, evidence does not support a long-term benefit for weight loss or in diabetes. Because its breakdown products include phenylalanine, people with the genetic condition phenylketonuria (PKU) must be aware of this as an additional source.It was first sold under the brand name NutraSweet. It was first made in 1965, and the patent expired in 1992. It was initially approved for use in food products by the U.S. Food and Drug Administration (FDA) in 1981. The safety of aspartame has been the subject of several political and medical controversies, United States congressional hearings, and Internet hoaxes.Benzyl alcohol
Benzyl alcohol is an aromatic alcohol with the formula C6H5CH2OH. The benzyl group is often abbreviated "Bn" (not to be confused with "Bz" which is used for benzoyl), thus benzyl alcohol is denoted as BnOH. Benzyl alcohol is a colorless liquid with a mild pleasant aromatic odor. It is a useful solvent due to its polarity, low toxicity, and low vapor pressure. Benzyl alcohol has moderate solubility in water (4 g/100 mL) and is miscible in alcohols and diethyl ether. The anion produced by deprotonation of the alcohol group is known as benzylate or benzyloxide.Denatured alcohol
Denatured alcohol, also called methylated spirit (in Australia, New Zealand, South Africa and the United Kingdom) or denatured rectified spirit, is ethanol that has additives to make it poisonous, bad-tasting, foul-smelling, or nauseating to discourage recreational consumption. It is sometimes dyed. Pyridine, methanol, or both can be added to make denatured alcohol poisonous, and denatonium can be added to make it bitter.
Denatured alcohol is used as a solvent and as fuel for alcohol burners and camping stoves. Because of the diversity of industrial uses for denatured alcohol, hundreds of additives and denaturing methods have been used. The main additive has traditionally been 10% methanol, giving rise to the term "methylated spirits". Other typical additives include isopropyl alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, and denatonium.In the United States, mixtures sold as denatured alcohol often have much greater percentages of methanol, and can be less than 50% ethanol.
Denaturing alcohol does not chemically alter the ethanol molecule. Rather, the ethanol is mixed with other chemicals to form a toxic or bad tasting solution. For many of these solutions, there is no practical way to separate the components.Direct methanol fuel cell
Direct-methanol fuel cells or DMFCs are a subcategory of proton-exchange fuel cells in which methanol is used as the fuel. Their main advantage is the ease of transport of methanol, an energy-dense yet reasonably stable liquid at all environmental conditions.
Efficiency is quite low for these cells, so they are targeted especially to portable applications, where energy and power density are more important than efficiency.
A more efficient version of a direct fuel cell would play a key role in the theoretical use of methanol as a general energy transport medium, in the hypothesized methanol economy.Fomepizole
Fomepizole, also known as 4-methylpyrazole, is a medication used to treat methanol and ethylene glycol poisoning. It may be used alone or together with hemodialysis. It is given by injection into a vein.Common side effects include headache, nausea, sleepiness, and unsteadiness. It is unclear if use during pregnancy is safe for the baby. Fomepizole works by blocking the enzyme that converts methanol and ethylene glycol to their toxic breakdown products.Fomepizole was approved for medical use in the United States in 1997. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. In the United States each vial costs about 1000 USD.Gas to liquids
Gas to liquids (GTL) is a refinery process to convert natural gas or other gaseous hydrocarbons into longer-chain hydrocarbons, such as gasoline or diesel fuel. Methane-rich gases are converted into liquid synthetic fuels. Two general strategies exist: (i) direct partial combustion of methane to methanol and (ii) Fischer-Tropsch-like processes that convert carbon monoxide and hydrogen into hydrocarbons. Strategy ii is followed by diverse methods to convert the hydrogen-carbon monoxide mixtures to liquids. Direct partial combustion has been demonstrated in nature but not replicated commercially. Technologies reliant on partial combustion have been commercialized mainly in regions where natural gas is inexpensive.The motivation for GTL is to produce liquid fuels, which are more readily transported than methane. Methane must be cooled below its critical temperature of -82.3 °C in order to be liquified under pressure. Because of the associated cryogenic apparatus, LNG tankers are expensive, not to mention potentially dangerous. Methanol is a conveniently handled combustible liquid, but its energy density is half of that of gasoline.Indole-3-carbinol
Indole-3-carbinol (C9H9NO) is produced by the breakdown of the glucosinolate glucobrassicin, which can be found at relatively high levels in cruciferous vegetables such as broccoli, cabbage, cauliflower, brussels sprouts, collard greens and kale. It is also available in dietary supplements. Indole-3-carbinol is the subject of on-going biomedical research into its possible anticarcinogenic, antioxidant, and anti-atherogenic effects. Research on indole-3-carbinol has been conducted primarily using laboratory animals and cultured cells. Limited and inconclusive human studies have been reported. A recent review of the biomedical research literature found that "evidence of an inverse association between cruciferous vegetable intake and breast or prostate cancer in humans is limited and inconsistent" and "larger randomized controlled trials are needed" to determine if supplemental indole-3-carbinol has health benefits.Methanex
Methanex Corporation is a Canadian company that supplies, distributes and markets methanol worldwide.Methanex is the world’s largest producer and supplier of methanol to major international markets in North America, Asia Pacific, Europe and South America. Methanex is headquartered in Vancouver, British Columbia, Canada, and operates production sites in Canada, Chile, Egypt, New Zealand, the United States and Trinidad and Tobago. Its global operations are supported by an extensive global supply chain of terminals, storage facilities and the world’s largest dedicated fleet of methanol ocean tankers.Methanex Corporation challenged California's plan to eliminate methyl tertiary butyl ether (MTBE) from gasoline on grounds of water pollution prevention, claiming protection under Chapter 11 of NAFTA and demanding $970 million in compensation from the state.In January 2012, Methanex announced it would move one of its idle Chilean plants to the United States. Methanex later confirmed that they acquired land in Geismar, LA and Geismar would be the site in the United States where the idle Chilean plant would be moved to. Methanex CEO, Bruce Aitken, confirmed in a press release on January 17, 2012 that the reason Methanex was shifting a methanol production plant from Chile to North America, specifically Louisiana, is due to the low price of natural gas available in North America and Louisiana.Regional marketing offices are located in Belgium, Chile, China, Egypt, Korea, Japan, the United Arab Emirates, the United Kingdom and the United States.Methanol economy
The methanol economy is a suggested future economy in which methanol and dimethyl ether replace fossil fuels as a means of energy storage, ground transportation fuel, and raw material for synthetic hydrocarbons and their products. It offers an alternative to the proposed hydrogen economy or ethanol economy.
In the 1990s, Nobel prize winner George A. Olah advocated a methanol economy; in 2006, he and two co-authors, G. K. Surya Prakash and Alain Goeppert, published a summary of the state of fossil fuel and alternative energy sources, including their availability and limitations, before suggesting a methanol economy.Methanol can be produced from a wide variety of sources including still-abundant fossil fuels (natural gas, coal, oil shale, tar sands, etc.) as well as agricultural products and municipal waste, wood and varied biomass. It can also be made from chemical recycling of carbon dioxide.Methanol fuel
Methanol is an alternative fuel for internal combustion and other engines, either in combination with gasoline or directly . It is used in racing cars in many countries. In the U.S., methanol fuel has received less attention than ethanol fuel as an alternative to petroleum-based fuels. In general, ethanol is less toxic and has higher energy density, although methanol is less expensive to produce sustainably and is a less expensive way to reduce the carbon footprint. However, for optimizing engine performance, fuel availability, toxicity and political advantage, a blend of ethanol, methanol and petroleum is likely to be preferable to using any of these individual substances alone. Methanol may be made from hydrocarbon or renewable resources, in particular natural gas and biomass respectively. It can also be synthesized from CO2 (carbon dioxide) and hydrogen.Methanol toxicity
Methanol toxicity is poisoning from methanol. Symptoms may include a decreased level of consciousness, poor coordination, vomiting, abdominal pain, and a specific smell on the breath. Decreased vision may start as early as twelve hours after exposure. Long term outcomes may include blindness and kidney failure. Toxicity and death may occur even after drinking a small amount.Methanol poisoning most commonly occurs following the drinking of windshield washer fluid. This may be accidental or done purposefully in an attempt to die by suicide. Toxicity may also rarely occur through skin exposure or breathing in the fumes. When methanol is broken down by the body it results in formaldehyde, formic acid, and formate which cause much of the toxicity. The diagnosis may be suspected when there is acidosis or an increased osmol gap and confirmed by directly measuring blood levels. Other conditions that can produce similar symptoms include infections, exposure to other toxic alcohols, serotonin syndrome, and diabetic ketoacidosis.Early treatment increases the chance of a good outcome. Treatment consists of stabilizing the person, followed by the use of an antidote. The preferred antidote is fomepizole, with ethanol used if this is not available. Hemodialysis may also be used in those where there is organ damage or a high degree of acidosis. Other treatments may include sodium bicarbonate, folate, and thiamine.Outbreaks have occurred due to contamination of drinking alcohol. This is more common in the developing world. In 2013 more than 1700 cases occurred in the United States. Those affected are often adults and male. Toxicity to methanol has been described as early as 1856.Petrochemical
Petrochemicals (also known as petroleum distillates) are chemical products derived from petroleum. Some chemical compounds made from petroleum are also obtained from other fossil fuels, such as coal or natural gas, or renewable sources such as corn, palm fruit or sugar cane.
The two most common petrochemical classes are olefins (including ethylene and propylene) and aromatics (including benzene, toluene and xylene isomers).
Oil refineries produce olefins and aromatics by fluid catalytic cracking of petroleum fractions. Chemical plants produce olefins by steam cracking of natural gas liquids like ethane and propane. Aromatics are produced by catalytic reforming of naphtha. Olefins and aromatics are the building-blocks for a wide range of materials such as solvents, detergents, and adhesives. Olefins are the basis for polymers and oligomers used in plastics, resins, fibers, elastomers, lubricants, and gels.Global ethylene and propylene production are about 115 million tonnes and 70 million tonnes per annum, respectively. Aromatics production is approximately 70 million tonnes. The largest petrochemical industries are located in the USA and Western Europe; however, major growth in new production capacity is in the Middle East and Asia. There is substantial inter-regional petrochemical trade.
Primary petrochemicals are divided into three groups depending on their chemical structure:
Olefins includes Ethene, Propene, Butenes and butadiene. Ethylene and propylene are important sources of industrial chemicals and plastics products. Butadiene is used in making synthetic rubber.
Aromatics includes Benzene, toluene and xylenes, as a whole referred to as BTX and primarily obtained from petroleum refineries by extraction from the reformate produced in catalytic reformers using Naphtha obtained from petroleum refineries. Benzene is a raw material for dyes and synthetic detergents, and benzene and toluene for isocyanates MDI and TDI used in making polyurethanes. Manufacturers use xylenes to produce plastics and synthetic fibers.
Synthesis gas is a mixture of carbon monoxide and hydrogen used to make ammonia and methanol. Ammonia is used to make the fertilizer urea and methanol is used as a solvent and chemical intermediate. Steam crackers are not to be confused with steam reforming plants used to produce hydrogen and ammonia.
Methane, ethane, propane and butanes obtained primarily from natural gas processing plants.
Methanol and formaldehyde.In 2007, the amounts of ethylene and propylene produced in steam crackers were about 115 Mt (megatonnes) and 70 Mt, respectively. The output ethylene capacity of large steam crackers ranged up to as much as 1.0 – 1.5 Mt per year.
The adjacent diagram schematically depicts the major hydrocarbon sources and processes used in producing petrochemicals.
Like commodity chemicals, petrochemicals are made on a very large scale. Petrochemical manufacturing units differ from commodity chemical plants in that they often produce a number of related products. Compare this with specialty chemical and fine chemical manufacture where products are made in discrete batch processes.
Petrochemicals are predominantly made in a few manufacturing locations around the world, for example in Jubail & Yanbu Industrial Cities in Saudi Arabia, Texas & Louisiana in the US, in Teesside in the Northeast of England in the United Kingdom, in Rotterdam in the Netherlands, and in Jamnagar & Dahej in Gujarat, India. Not all of the petrochemical or commodity chemical materials produced by the chemical industry are made in one single location but groups of related materials are often made in adjacent manufacturing plants to induce industrial symbiosis as well as material and utility efficiency and other economies of scale. This is known in chemical engineering terminology as integrated manufacturing. Speciality and fine chemical companies are sometimes found in similar manufacturing locations as petrochemicals but, in most cases, they do not need the same level of large scale infrastructure (e.g., pipelines, storage, ports and power, etc.) and therefore can be found in multi-sector business parks.
The large scale petrochemical manufacturing locations have clusters of manufacturing units that share utilities and large scale infrastructure such as power stations, storage tanks, port facilities, road and rail terminals. In the United Kingdom for example, there are 4 main locations for such manufacturing: near the River Mersey in Northwest England, on the Humber on the East coast of Yorkshire, in Grangemouth near the Firth of Forth in Scotland and in Teesside as part of the Northeast of England Process Industry Cluster (NEPIC). To demonstrate the clustering and integration, some 50% of the United Kingdom's petrochemical and commodity chemicals are produced by the NEPIC industry cluster companies in Teesside.Reformed methanol fuel cell
Reformed Methanol Fuel Cell (RMFC) or Indirect Methanol Fuel Cell (IMFC) systems are a subcategory of proton-exchange fuel cells where, the fuel, methanol (CH3OH), is reformed, before being fed into the fuel cell. RMFC systems offer advantages over direct methanol fuel cell (DMFC) systems including higher efficiency, smaller cell stacks, no water management, better operation at low temperatures, and storage at sub-zero temperatures because methanol is a liquid from -97.0 °C to 64.7 °C (-142.6 °F to 148.5 °F). The tradeoff is that RMFC systems operate at hotter temperatures and therefore need more advanced heat management and insulation. The waste products with these types of fuel cells are carbon dioxide and water.
Methanol is used as a fuel because it is naturally hydrogen dense (a hydrogen carrier) and can be steam reformed into hydrogen at low temperatures compared to other hydrocarbon fuels. Additionally, methanol is naturally occurring, biodegradable, and energy dense.
RMFC systems consist of a fuel processing system (FPS), a fuel cell, a fuel cartridge, and the BOP (the balance of plant).Syngas
Syngas, or synthesis gas, is a fuel gas mixture consisting primarily of hydrogen, carbon monoxide, and very often some carbon dioxide. The name comes from its use as intermediates in creating synthetic natural gas (SNG) and for producing ammonia or methanol. Syngas is usually a product of gasification and the main application is electricity generation. Syngas is combustible and often used as a fuel of internal combustion engines. It has less than half the energy density of natural gas.Syngas can be produced from many sources, including natural gas, coal, biomass, or virtually any hydrocarbon feedstock, by reaction with steam (steam reforming), carbon dioxide (dry reforming) or oxygen (partial oxidation). Syngas is a crucial intermediate resource for production of hydrogen, ammonia, methanol, and synthetic hydrocarbon fuels. Syngas is also used as an intermediate in producing synthetic petroleum for use as a fuel or lubricant via the Fischer–Tropsch process and previously the Mobil methanol to gasoline process.
Production methods include steam reforming of natural gas or liquid hydrocarbons to produce hydrogen, the gasification of coal, biomass, and in some types of waste-to-energy gasification facilities.Top Alcohol
Top Alcohol refers to two different classes in professional drag racing: Top Alcohol Dragster and the Top Alcohol Funny Car. Commonly known as "alky" cars, both are akin in design to the premier Top Fuel classes, but less powerful (about 3,500 bhp (2,600 kW; 3,500 PS)). In Top Alcohol Dragster, the cars used supercharged ("blown") engines, burning alcohol (methanol). Top Alcohol Funny Cars look similar to Fuel Funny Cars, with about half the power of a Top Fuel car. In this class only alcohol cars with three-speed transmissions are allowed.Top Alcohol was devised in the 1970s as a replacement for the Top Gas class, which was similar but burned gasoline. Initially, alcohol dragsters competed against Funny Cars in a category known as Pro Comp, before a separate class, Top Alcohol Funny Car, was created in the 1980s. It was within IHRA's version of this class use of ethanol fuel was pioneered with great success by Mark Thomas, an Ohio farmer who became a five-time champion within that organization. Despite this, ethanol has failed to capture the imagination of racers; the majority opt for more traditional methanol. Today both Top Alcohol Dragster and Top Alcohol Funny Car compete in NHRA drag racing. They are classed not as professional but as sportsman within the USA but in Europe they are classed as a professional category within the FIA Drag Racing Championships. Top Alcohol classes also compete outside of North America, most notably in Australia and Europe. In Europe they are called Top Methanol Dragsters and Top Methanol Funny Cars.Water injection (engine)
In internal combustion engines, water injection, also known as anti-detonant injection (ADI), can spray water into the incoming air or fuel-air mixture, or directly into the cylinder to cool certain parts of the induction system where "hot points" could produce premature ignition. In jet engines it increases engine thrust at low speeds and at takeoff.
Water injection was used historically to increase the power output of military aviation engines for short durations, such as dogfights or takeoff. However it has also been used in motor sports and notably in drag racing. In Otto cycle engines, the cooling effects of water injection also enables greater compression ratios by reducing engine knocking (detonation). Alternately, this reduction in engine knocking in Otto cycle engines means that some applications gain significant performance when water injection is used in conjunction with a supercharger, turbocharger, or modifications such as aggressive ignition timing.
Depending on the engine, improvements in power and fuel efficiency can also be obtained solely by injecting water. Water injection may also be used to reduce NOx or carbon monoxide emissions.Water injection is also used in some turbine engines and in some turboshaft engines, normally when a momentary high-thrust setting is needed to increase power and fuel efficiency.
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See also: Receptor/signaling modulators • GABA receptor modulators • GABA metabolism/transport modulators