Methyl ethyl ketone (also known as MEK, butanone, 2-butanone, butan-2-one, oxobutane, or methyl acetone) is a clear volatile liquid that is soluble in water and has a mild, acetone odour. It has the formula C4H8O.
Methyl ethyl ketone does occur naturally as it is biosynthesized by some trees and is also found in small amounts in some fruits and vegetables as well as in chicken, honey and a variety of cheeses.
The main commercial production route for methyl ethyl ketone is through the dehydrogenation of secondary butanol although newer technology involves the direct oxidation of n-butene in solution, using palladium and cupric chlorides as catalysts.
The Chinese market is the main driver for the demand of MEK and is also where several new productions plants have been opened in the last 5 years. World production now stands at approximately 320,000 to 350,000 tonnes.
Storage and distribution
Methyl ethyl ketone is packed in drums. It should be stored in a cool, dry, well-ventilated area that is free form the risk of ignition as it is highly flammable. For transportation purposes methyl ethyl ketone is classified as packing group II and hazard class 3 and has a flash point of -9° C (closed cup) and a specific gravity of 0.81. It is also an irritant.
Over 50 % of the demand for Methyl ethyl ketone stems from the paints and coatings industry as a low viscosity solution can be obtained without it affecting the film properties of the product. These lacquers are used in the automotive, electrical goods, and furniture industries.
MEK is also used in the manufacture of plastics and textiles, the manufacture of printing inks, and also in rubber-based industrial cements. It is also used in the chemical industry as it is a precursor to methyl ethyl ketone peroxide which is itself used as a catalyst to initiate the polymerisation of polyester resins used in fibre-glass reinforced products.