Butane ( ) is an organic compound of the formula C 4 H 10 which is an alkane with four carbon atoms. Butane is a gas at room temperature and atmospheric pressure. This term may refer to either of the two structural isomers, or isobutane -this isomer. In the IUPAC nomenclature, however, "butane" refers only to the n -butane isomer (which is an isomer with an unbranched structure). Butan is highly flammable, colorless, easily liquefied rapidly evaporating gas at room temperature. The butane name is derived from but-root (from butyric acid, named after the Greek word for butter) and -ane. It was discovered by the chemist Edward Frankland in 1849.
Video Butane
Isomer
The rotation of the central C-C bond produces two different conformations ( trans and gauche ) for n -butane.
Maps Butane
Reaction
When oxygen is abundant, butane burns to form carbon dioxide and water vapor; when oxygen is limited, carbon (carbon black) or carbon monoxide can also form.
When there is enough oxygen:
- 2 C 4 H 10 13 O 2 -> 8 CO 2 10 H < sub> 2 O
Ketika oksigen terbatas:
The maximum adiabatic flame temperature with air is 2,243 Â ° K (1,970 ° C; 3,578 ° F).
n -Butane is the raw material for the DuPont catalytic process for the preparation of maleic anhydride:
n -Butane, like all hydrocarbons, undergoes free radical chlorination providing both 1-chloro- and 2-chlorobutane, as well as higher chlorinated derivatives. The relative level of chlorination is partially explained by different bonding dissociation energies, 425 and 411 kJ/mol for two types of C-H bonds.
Usage
Normal butane may be used for gasoline mixtures, as a gas fuel, extraction solvent extraction, either alone or in mixtures with propane, and as a feedstock for the preparation of ethylene and butadiene, the principal ingredients of synthetic rubber. Isobutane is mainly used by refineries to increase (add) the octane number of motor gasoline.
When mixed with propane and other hydrocarbons, it can be referred to commercially as LPG, for liquid petroleum gas. It is used as a gasoline component, as a feedstock for basic petrochemical production in steam cracking, as a fuel for cigarette lighter and as a propellant in aerosol sprays such as deodorants.
A very pure form of butane, especially isobutane, can be used as a refrigerant and has replaced most of the ozone layer halomethan, for example in refrigerators and household freezers. The operating pressure of the system for butane is lower than for halomethan, such as R-12, so that R-12 systems as in automotive air conditioning systems, when converted to pure butane will not function optimally and therefore a mixture of isobutane and propane is used to provide system performance cooler comparable to R-12.
Butane is also used as a lighter fuel for light or common butane torches and sold bottles as fuel for cooking, barbecue and camping stoves. The butane tube is almost exclusively manufactured in South Korea with the sole exception being one manufacturer in Houston, Texas. Butane tubes produced in South Korea contain butane from Saudi Arabia, while American producers fill tubes with domestic butane.
In this form it is often mixed with small amounts of hydrogen sulfide and mercaptans that will provide unburned gas offensive odors easily detectable by the human nose. In this way, the butane leak can be easily identified. While hydrogen sulfide and mercaptan are toxic, they present at very low levels so that suffocation and fire hazard by butane are of concern long before poisoning. The most commercially available butane also contains a number of contaminant oils that can be removed through screening but which otherwise will leave the deposit at the point of ignition and can ultimately block uniform gas flow. Contaminants not used in extraction of aroma and butane gas can cause gas explosions in poorly ventilated areas if leaks are not detected and ignited by sparks or flame.
Health effects and issues
Butane inhalation may cause euphoria, drowsiness, narcosis, asphyxia, cardiac arrhythmias, blood pressure fluctuations and temporary memory loss, when misused directly from high pressure containers, and may result in death from asphyxia and ventricular fibrillation. This enters the blood supply and in a few seconds results in intoxication. Butane is the most commonly abused volatile agent in the UK, and is the cause of 52% solvent-related deaths in 2000. By spraying butane directly into the throat, the liquid jets can cool rapidly to -20 ° C (-4 Ã, Â ° F ) with expansion, causing prolonged laryngospasm spasm. The "sudden death sniffer" syndrome, first described by Bass in 1970, is the single most common cause of solvent-related deaths, resulting in 55% of known fatal cases.
A small amount of nitrogen dioxide, a toxic gas, results from the combustion of butane gas, along with any combustion in the Earth's atmosphere, and represents the human health hazards of home heating and stove.
See also
- Isobutane
- Cyclobutane
- Dimethyl ether
- substance abuse Volatile
- Butana (data page)
- Butanone
- n -Butanol
- Liquid petroleum gas
- Industrial gas
- Butana Torch
- Gas explosion
References
External links
- International Chemical Safety Card 0232
- The NIOSH Pocket Guide for Chemical Hazards
Source of the article : Wikipedia
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