METHANOL

Methanol, also known as methyl alcohol, carbinol, wood alcohol, wood naphtha or wood spirits, is a toxic chemical with chemical formula CH3OH (often abbreviated MeOH). Pure methanol, however, was first isolated in 1661 by Robert Boyle, The largest use of methanol by far is in making other chemicals. About 40% of methanol is converted to formaldehyde, and from there into products as diverse as plastics, plywood, paints, explosives, and permanent press textiles.
Also in the early 1970s, a Methanol to gasoline process was developed by Mobil for producing gasoline ready for use in vehicles. One such industrial facility was built at Motunui in New Zealand in the 1980s. In the 1990s, large amounts of methanol were used in the United States to produce the gasoline additive methyl tert-butyl ether (MTBE). While MTBE is no longer marketed in the U.S., it is still widely used in other parts of the world. In addition to direct use as a fuel, methanol (or less commonly, ethanol) is used as a component in the transesterification of triglycerides to yield a form of biodiesel.Each year, 12 billion gallons of methanol are consumed worldwide for the production of hundreds of essential chemical commodities. Most methanol is produced from natural gas or coal in large manufacturing plants with capacities often exceeding several hundred million gallons per year. Also known as "wood alcohol," methanol can be made from a host of renewable feedstocks. "No other alternative fuel offers as many conventional and renewable production pathways asmethanol," said Lynn.
"Our national security, economic vitality and environmental future demand that we diversify our energy portfolio. We need look no further than methanol. With the ability to use methanol in today's car engines and electric turbines, and as a hydrogen carrier fuel for tomorrow's fuel cell technology, methanol is the clear alternative." Methanol has been identified as a natural emission product from various plants and as a biological decomposition product of biological wastes and sewage. The largest anthropogenic source of methanol release to the environment is evaporation from solvent uses (1.1 billion lb/yr). If released to the atmosphere, methanol degrades via reaction with photochemically produced hydroxyl radicals with an approximate half-life of 17.8 days. Physical removal from air can occur via rainfall. If released to water, decomposition via biodegradation is expected to occur. If released to soil, methanol is expected to degrade via biodegradation and be susceptible to significant leaching. Relatively rapid evaporation from dry surfaces is likely to occur. Occupational and general exposure occurs through inhalation and dermal contact. Exposure also occurs through consumption of various foods and waters. TERRESTRIAL FATE: Methanol is expected to be biodegradable in soil based on the results of a large number of biological screening studies, which include soil microcosm studies. Its miscibility in water and log Kow (-0.77) suggest high mobility in soil. Based on a vapor pressure of 92 mm Hg at 20 deg C , evaporation from dry surfaces can be expected to occur. AQUATIC FATE: The important environmental fate process for methanol in water is biodegradation. A large number of screening studies have found methanol to be significantly biodegradable. Volatilization half-lifes of 4.8 days and 51.7 days have been estimated for a model river (1 m deep) and an environmental pond, respectively. Aquatic hydrolysis, oxidation, photolysis, adsorption to sediment, and bioconcentration are not significant. ATMOSPHERIC FATE: Methanol is expected to exist almost entirely in the vapor-phase in the ambient atmosphere, based on a vapor pressure of 92 mm Hg at 20 deg C(1,2,SRC). It is degraded by reaction with photochemically produced hydroxyl radicals with an estimated half-life of 17.8 days in a typical ambient atmosphere. Atmospheric methanol can also react with nitrogen dioxide in polluted air to yield methyl nitrite. Because of methanol's water solubility, rain would be expected to physically remove some from the air ; the detection of methanol in a thunderstorm water tends to confirm this supposition.