2-Butanone Chemical Properties
- Melting point:
- -87 °C
- Boiling point:
- 80 °C(lit.)
- vapor density
- 2.49 (vs air)
- vapor pressure
- 71 mm Hg ( 20 °C)
- refractive index
- 2170 | 2-BUTANONE
- Flash point:
- 26 °F
- storage temp.
- Miscible with acetone, ethanol, benzene, ether (U.S. EPA, 1985), and many other solvents, particularly ketones and aldehydes
- 14.7 (quoted, Riddick et al., 1986)
- Sweet/sharp odor detectable at 2 to 85 ppm (mean = 16 ppm)
- pH(1+4, 25℃):6.0～7.0
- Relative polarity
- Odor Threshold
- explosive limit
- Water Solubility
- 290 g/L (20 ºC)
- JECFA Number
- Henry's Law Constant
- 23.0 at 50.00 °C, 34.1 at 60.00 °C, 50.6 at 70.00 °C, 70.4 at 80.00 °C (headspace-GC, Hovorka et al., 2002)
- Exposure limits
- TLV-TWA, PEL 590 mg/m3 (200 ppm) (ACGIH, OSHA); STEL 885 mg/m3 (300 ppm) (ACGIH); IDLH 3000 ppm (NIOSH).
- Stable. Highly flammable. Incompatible with oxidizing agents, bases, strong reducing agents. Protect from moisture.
- CAS DataBase Reference
- 78-93-3(CAS DataBase Reference)
- NIST Chemistry Reference
- EPA Substance Registry System
- Methyl ethyl ketone (78-93-3)
- Hazard Codes
- Risk Statements
- Safety Statements
- UN 1193 3/PG 2
- WGK Germany
- Autoignition Temperature
- 516 °C
- HS Code
- Hazardous Substances Data
- 78-93-3(Hazardous Substances Data)
- LD50 orally in rats: 6.86 ml/kg (Smyth)
2-Butanone Usage And Synthesis
2-Butanone is a stable, highly flammable chemical. It is incompatible with oxidising agents, bases, and strong reducing agents. It is a colourless liquid with a sharp, sweet odour. 2-Butanone is produced in large quantities. It is used as a solvent and nearly half of its use is in paints and other coatings because it will quickly evaporate into the air and it dissolves many substances. It is also used in glues and as a cleaning agent.
2-Butanone is a stable, highly flammable chemical. It is incompatible with oxidizing agents, bases, and strong reducing agents. It is a colorless liquid with a sharp, sweet odor. 2-Butanone is produced in large quantities. It is used as a solvent and nearly half of its use is in paints and other coatings because it quickly evaporates into the air and it dissolves many substances. It is also used in glues and as a cleaning agent.
MEK is a clear, colorless liquid. Fragrant, mint-like, moderately sharp odor.
2-Butanone is a liquid with a sweet apricot-like odor.
Clear, colorless, volatile, very flammable liquid with a sweet, mint or acetone-like odor. Odor threshold concentration is 10.0 ppmv (Leonardos et al., 1969). Experimentally determined detection and recognition odor threshold concentrations were 5.8 mg/m3 (2.0 ppmv) and 16 mg/m3 (5.4 ppmv), respectively (Hellman and Small, 1974).
Reported found as an impurity among products from the dry distillation of wood and in the oil (extracted with ether) of black tea; it is also present in coffee, cheese, bread, some citrus oils and some other natural products (grape, raspberry).
Methyl ethyl ketone (MEK) is used in themanufacture of smokeless powder and colorless synthetic resins, as a solvent, and insurface coating. It is also used as a flavoringsubstance in food.
As solvent; in the surface coating industry; manufacture of smokeless powder; colorless synthetic resins.
2-Butanone is an eye irritant that has been used as a water soluble photoinitiator for the photopolymerization of methacrylic acid (MAA).
ChEBI: A dialkyl ketone that is a four-carbon ketone carrying a single keto- group at position C-2.
A colorless volatile liquid ketone. It is manufactured by the oxidation of butane and used as a solvent.
By catalytic dehydrogenation of secondary butyl alcohol; by dehydration of butane-2,3-diol by refluxing with 25% aqueous H2SO4. Industrially, it is also prepared by controlled oxidation of butane, by dry distillation of calcium acetate and calcium propionate, or by refluxing methyl acetoacetate and diluted H2SO4.
Methyl ethyl ketone is commercially manufactured from nbutene in a metal-catalyzed hydrogenation reaction that proceeds through the intermediate formation of 2-butanol . A second method of synthesis involves the liquid- phase oxidation of n-butane with the formation of acetic acid as a coproduct.
Taste threshold values
Taste characteristics at 5 ppm: chemical-like and slightly fruity green.
Methyl ethyl ketone (MEK) is a colourless liquid with a sweet and sharp odour. It is soluble in alcohol, ether, acetone benzene, and water. It is a solvent often found in mixtures with acetone, ethyl acetate, n-hexane, toluene, or alcohols. It has applications in the surface coating industry and in the de-waxing of lubricating oils. MEK is used in the manufacture of colourless synthetic resins, artificial leather, rubbers, lacquers, varnishes, and glues.
Air & Water Reactions
Highly flammable. Slightly soluble in water.
Amines are chemical bases. They neutralize acids to form salts plus water. These acid-base reactions are exothermic. The amount of heat that is evolved per mole of amine in a neutralization is largely independent of the strength of the amine as a base. Amines may be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated by amines in combination with strong reducing agents, such as hydrides. Ketones are reactive with many acids and bases liberating heat and flammable gases (e.g., H2). The amount of heat may be sufficient to start a fire in the unreacted portion of the ketone. Ketones react with reducing agents such as hydrides, alkali metals, and nitrides to produce flammable gas (H2) and heat. Ketones are incompatible with isocyanates, aldehydes, cyanides, peroxides, and anhydrides. They react violently with aldehydes, HNO3, HNO3 + H2O2, and HClO4.
Flammable, dangerous fire risk. Toxic by ingestion.
May cause toxic effects if inhaled or ingested/swallowed. Contact with substance may cause severe burns to skin and eyes. Fire will produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution.
Occupational workers are exposed to 2-butanone by breathing contaminated air in workplaces associated with the production or use of paints, glues, coatings, or cleaning agents. Prolonged exposures to 2-butanone cause symptoms of poisoning such as cough, dizziness, drowsiness, headache, nausea, vomiting, dermatitis, irritation of the nose, throat, skin, and eyes and at very high levels cause drooping eyelids, uncoordinated muscle movements, loss of consciousness, and birth defects. Chronic inhalation studies in animals have reported slight neurological, liver, kidney, and respiratory effects. However, information on the chronic (long-term) effects of 2-butanone (methyl ethyl ketone) in humans is limited.
Inhalation of MEK can cause irritation ofthe eyes and nose and headache. Exposureto 300 ppm for several hours may have amildly irritating effect on humans. At highconcentrations it is narcotic. Ingestion cancause dizziness and vomiting. Serious illeffects from poisoning is low.
LD50 value, oral (rats): 5500 mg/kg
Odor threshold detection: 10 ppm.
The acute toxicity of methyl ethyl ketone is low. Exposure to high concentrations
can cause headache, dizziness, drowsiness, vomiting, and numbness of the
extremities. Irritation of the eyes, nose, and throat can also occur. Methyl ethyl
ketone is considered to have adequate warning properties.
Repeated or prolonged skin exposure to methyl ethyl ketone can cause defatting of the skin, leading to cracking, secondary infection, and dermatitis. This compound has not been found to be carcinogenic or to show reproductive or developmental toxicity in humans. Methyl ethyl ketone has exhibited developmental toxicity in some animal tests
Methyl ethyl ketone is extremely flammable (NFPA rating = 3), and its vapor can travel a considerable distance to an ignition source and "flash back." MEK vapor forms explosive mixtures with air at concentrations of 1.9 to 11% (by volume). Carbon dioxide or dry chemical extinguishers should be used for MEK fires
Flammable/combustible material. May be ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water.
Flammability and Explosibility
Methyl ethyl ketone is extremely flammable (NFPA rating = 3), and its vapor can travel a considerable distance to an ignition source and "flash back." MEK vapor forms explosive mixtures with air at concentrations of 1.9 to 11% (by volume). Carbon dioxide or dry chemical extinguishers should be used for MEK fires.
Reactivity with Water No reaction; Reactivity with Common Materials: No reaction; Stability During Transport: Stable; Neutralizing Agents for Acids and Caustics: Not pertinent; Polymerization: Not pertinent; Inhibitor of Polymerization: Not pertinent.
Moderately toxic by ingestion, skin contact, and intraperitoneal routes. Human systemic effects by inhalation: conjunctiva irritation and unspecified effects on the nose and respiratory system. An experimental teratogen. A strong irritant. Human eye irritation @ 350 ppm. Affects peripheral nervous system and central nervous system. Highly flammable liquid. Reaction with hydrogen peroxide + nitric acid forms a heatand shock-sensitive explosive product. Ignition on contact with potassium tert-butoxide. Mixture with 2- propanol will produce explosive peroxides during storage. Vigorous reaction with chloroform + alkali. Incompatible with chlorosulfonic acid, oleum. To fight fire, use alcohol foam, CO2, dry chemical. Used in production of drugs of abuse. When heated to decomposition it emits acrid smoke and fumes.
MEK is used as a solvent in nitrocellulose coating and vinyl film manufacture; in smokeless powder manufacture; in cements and adhesives and in the dewaxing of lubricating oils. It is also an intermediate in drug manufacture
Although MEK has not been specifically examined in a rodent 2-year bioassay, there is little to suggest that the material is carcinogenic. When used as a delivery vehicle in a dermal carcinogenicity bioassay for organic sulfur compounds, Horton et al. found that the application of benzyl disulfide or phenylbenzylthiophene in a 25–29% solution of MEK in dodecylbenzene together failed to increase the incidence of benign skin papillomas in male C3H/HeJmice. The mice used in the experiments were treated twice a week for 52 weeks with the MEKcontaining test solution.
Improper disposal of cleaning fluids, adhesives, paints, and lacquers, and laboratory
solvent. Leaches from PVC cement used to join tubing (Wang and Bricker, 1979). Also present in
cigarette smoke (500 ppm) and exhaust from gasoline-powered engines (<0.1–2.6 ppm)
Gas-phase tailpipe emission rates from California Phase II reformulated gasoline-powered automobiles with and without catalytic converters were 0.47 and 32 mg/km, respectively (Schauer et al., 2002).
Schauer et al. (2001) measured organic compound emission rates for volatile organic compounds, gas-phase semi-volatile organic compounds, and particle phase organic compounds from the residential (fireplace) combustion of pine, oak, and eucalyptus. The gas-phase emission rates of 2-butanone were 215 mg/kg of pine burned, 115 mg/kg of oak burned, and 77 mg/kg of eucalyptus burned.
Biological. Following a lag time of approximately 5 h, 2-butanone degraded in activated sludge
(30 mg/L) at a rate constant ranging from 0.021 to 0.025/h (Urano and Kato, 1986).
Bridié et al. (1979) reported BOD and COD values of 2.03 and 2.31 g/g using filtered effluent from a biological sanitary waste treatment plant. These values were determined using a standard dilution method at 20 °C for a period of 5 d. The ThOD for 2-butanone is 2.44 g/g. Using the BOD technique to measure biodegradation, the mean 5-d BOD value (mM BOD/mM 2-butanone) and ThOD were 3.23 and 58.7%, respectively (Vaishnav et al., 1987).
Photolytic. Synthetic air containing gaseous nitrous acid and exposed to artificial sunlight (λ = 300–450 nm) photooxidized 2-butanone into peroxyacetyl nitrate and methyl nitrate (Cox et al., 1980). They reported a rate constant of 2.6 x 10-12 cm3/molecule?sec for the reaction of gaseous 2- butane with OH radicals based on a value of 8 x 10-12 cm3/molecule?sec for the reaction of ethylene with OH radicals.
The OH radical-initiated photooxidation of 2-butanone in a smog chamber produced peroxyacetyl nitrate and acetaldehyde (Cox et al., 1981). Reported rate constants for the reaction of 2-butanone with OH radicals in the atmosphere and in water are 1.15 x 10-13 and 1.50 x 10-13 cm3/molecule?sec, respectively (Wallington and Kurylo, 1987; Wallington et al., 1988a). The rate constant for the reaction of 2-butanone and OH radicals in the atmosphere at 300 K is 2.0 x 10-12 cm3/molecule?sec (Hendry and Kenley, 1979). Cox et al. (1981) reported a photooxidation half-life of 2.3 d for the reaction of 2-butanone and OH radicals in the atmosphere.
Chemical/Physical. 2-Butanone will not hydrolyze because it has no hydrolyzable functional group (Kollig, 1993).
Combustion in air will produce carbon monoxide (incomplete combustion), carbon dioxide, and water vapor.
At an influent concentration of 1.0 g/L, treatment with GAC resulted in an effluent concentration of 532 mg/L. The adsorbability of the carbon used was 94 mg/g carbon (Guisti et al., 1974).
2-Butanone should be protected from moisture.
UN1193 Methyl ethyl ketone or Ethyl methyl ketone, Hazard Class: 3; Labels: 3-Flammable liquid.
May form explosive mixture with air. Violent reaction with strong oxidizers, amines, ammonia, inorganic acids; caustics, isocyanates, pyridines. Incompatible with potassium tert-butoxide, 2-propanol, chlorosulfonic acid; oleum. Attacks some plastics. Ketones are incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides, nitrated amines, azo, diazo, azido compounds, carbamates, organic cyanates
Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform to EPA regulations governing storage, transportation, treatment, and waste disposal. Incineration
2-Butanone vapor and air mixtures are explosive. It reacts violently with strong oxidants and inorganic acids causing fi re and explosion hazard.