Acetone (2-propanone or dimethyl ketone) is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile, and flammable liquid with a characteristic pungent odor.
Acetone is miscible with water and serves as an important organic solvent in industry, home, and laboratory settings. About 6.7 million tonnes were produced worldwide in 2010, mainly for use as a solvent and for production of methyl methacrylate and bisphenol A, which are precursors to widely used plastics.Acetone, World Petrochemicals report, January 2010Stylianos Sifniades, Alan B. Levy, "Acetone" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. It is a common building block in organic chemistry. It serves as a solvent in household products such as nail polish remover and paint thinner. It has volatile organic compound (VOC)-exempt status in the United States.
Acetone is produced and disposed of in the human body through normal metabolic processes. Small quantities of it are present naturally in blood and urine. People with diabetic ketoacidosis produce it in larger amounts. Medical ketogenic diets that increase ketone bodies (acetone, β-hydroxybutyric acid and acetoacetic acid) in the blood are used to suppress epileptic attacks in children with treatment-resistant epilepsy.
Name From the 17th century, and before modern developments in organic chemistry nomenclature, acetone was given many different names. They included "spirit of Saturn", which was given when it was thought to be a compound of lead and, later, "pyro-acetic spirit" and "pyro-acetic ester".Mel Gorman, History of acetone (1600–1850), 1962
Prior to the name "acetone" being coined by French chemists, it was named "mesit" (from the Greek μεσίτης, meaning mediator) by Carl Reichenbach, who also said that methyl alcohol consisted of mesit and ethyl alcohol.C. Reichenbach (1834) "Ueber Mesit (Essiggeist) und Holzgeist" (On mesit (spirit of vinegar) and wood spirits), Annalen der Pharmacie, vol. 10, no. 3, pages 298–314. Names derived from mesit include mesitylene and mesityl oxide which were first synthesised from acetone.
In 1839, the name "acetone" began to be used, because it was obtained from acetic acid. Unlike many compounds with the acet- prefix which have a 2-carbon chain, acetone has a 3-carbon chain. That has caused confusion because there can not be a ketone with 2 carbons. The prefix refers to acetone's relation to vinegar (acetum in Latin, also the source of the words "acid" and "acetic"), rather than its chemical structure.
History Acetone was first produced by Andreas Libavius in 1606 by distillation of lead(II) acetate. In 1832, French chemist Jean-Baptiste Dumas and German chemist Justus von Liebig determined the empirical formula for acetone.Dumas, J. (1832) "Sur l'esprit pyro-acétique" (On pyro-acetic spirit), Annales de Chimie et de Physique, 2nd series, 49 : 208–210.Liebig, Justus (1832) "Sur les combinaisons produites par l'action du gas oléfiant et l'esprit acétique" (On compounds produced by the action of ethylene and acetic spirit), Annales de Chimie et de Physique, 2nd series, 49 : 146–204 (especially 193–204). In 1833, French chemists Antoine Bussy and Michel Chevreul decided to name acetone by adding the suffix -one to the stem of the corresponding acid (viz, acetic acid) just as a similarly prepared product of what was then confused with margaric acid was named margarone.Bussy, Antoine (1833) "De quelques Produits nouveaux obtenus par l'action des Alcalis sur les Corps gras à une haute température" (On some new products obtained by the action of alkalies on fatty substances at a high temperature), Annales de Chimie et de Physique, 2nd series, 53 : 398–412; see footnote on pp. 408–409. By 1852, Alexander William Williamson, an English chemist, realized that acetone was methyl acetyl;Williamson, A. W. (1852) "On Etherification," Journal of the Chemical Society, 4 : 229–239; (especially pp. 237–239). the following year, the French chemist Charles Frédéric Gerhardt concurred.Gerhardt, Charles (1853) "Researches sur les acids organiques anhydres" (Research on anhydrous organic acids), Annales de Chimie et de Physique, 3rd series, 37 : 285–342; see p. 339. In 1865, a German chemist, August Kekulé published the modern structural formula for acetone.Kekulé, Auguste (1865) "Sur la constitution des substances aromatiques," Bulletin de la Société chimique de Paris, 1 : 98–110; (especially p. 110).Kekulé, Auguste (1866) "Untersuchungen über aromatischen Verbindungen" (Investigations into aromatic compounds), Annalen der Chemie und Pharmacie, 137 : 129–196; (especially pp. 143–144). Johann Josef Loschmidt had presented the structure of acetone in 1861,Loschmidt, J. (1861) Chemische Studien Vienna, Austria-Hungary: Carl Gerold's Sohn. but his privately published booklet received little attention. During World War I, Chaim Weizmann developed the biochemical process for industrial production of acetone (Weizmann Process).Chaim Weizmann chemistryexplained.com
Production
Acetone is produced directly or indirectly from propene. Approximately 83% of acetone is produced via the cumene process; as a result, acetone production is tied to phenol production. In the cumene process, benzene is alkylated with propylene to produce cumene, which is oxidized by air to produce acetone and phenol:
Other processes involve the direct oxidation of propylene (Wacker-Hoechst process), or the hydration of propylene to give 2-propanol, which is oxidized (dehydrogenated) to acetone. Previously, acetone was produced by the dry distillation of acetates, for example calcium acetate in ketonic decarboxylation.
After that time during World War I, acetone was produced using acetone-butanol-ethanol fermentation with Clostridium acetobutylicum bacteria, which was developed by Chaim Weizmann (later the first president of Israel) in order to help the British war effort, in the preparation of Cordite. This acetone-butanol-ethanol fermentation was eventually abandoned when newer methods with better yields were found.
In 2010, the worldwide production capacity for acetone was estimated at 6.7 million tonnes per year. With 1.56 million tonnes per year, the United States had the highest production capacity, followed by Taiwan and China. The largest producer of acetone is Ineos Phenol, owning 17% of the world's capacity, with also significant capacity (7–8%) by Mitsui, Sunoco and Shell in 2010. Ineos Phenol also owns the world's largest production site (420,000 tonnes/annum) in Beveren, Belgium. The spot price of acetone in summer 2011 was 1100–1250 USD/tonne in the United States.Acetone (US Gulf) Price Report – Chemical pricing information . ICIS Pricing, Retrieved on 2012-11-26
Occurrence
Humans exhale 1.2 to 2.5 mg of acetone per day and it arises from the decarboxylation of acetoacetate. Small amounts of acetone are produced in the body by the decarboxylation of ketone bodies. Certain dietary patterns including prolonged fasting and high-fat low-carbohydrate dieting, can produce ketosis, in which acetone is formed in body tissue. Certain health conditions, such as alcoholism and diabetes, can produce ketoacidosis, uncontrollable ketosis that leads to a sharp, and potentially fatal, increase in the acidity of the blood. Since it is a byproduct of fermentation, acetone is a byproduct of the distillery industry.
Acetone is naturally occurring. It is produced by terrestrial vegetation, undefined ocean processes, incomplete combustion of biomass, or oxidation of hydrocarbons in the atmosphere.
Chemical properties Acetone is reluctant to form a hydrate: K = 10−3 M−1
Like most ketones, acetone exhibits the keto–enol tautomerism in which the nominal keto structure of acetone itself is in equilibrium with the enol isomer (prop-1-en-2-ol). In acetone vapor at ambient temperature, only 2.4% of the molecules are in the enol form.
In the presence of suitable catalysts, two acetone molecules also combine to form the compound diacetone alcohol , which on dehydration gives mesityl oxide . This product can further combine with another acetone molecule, with loss of another molecule of water, yielding phorone and other compounds.
Acetone is a weak Lewis base that forms adducts with soft acids like I2 and hard acids like phenol. Acetone also forms complexes with divalent metals.
Under ultraviolet light, acetone fluoresces. The flame temperature of pure acetone is 1980 °C.Haynes, p. 15.49 At its melting point (−96 °C) is claimed to polymerize to give a white elastic solid, soluble in acetone, stable for several hours at room temperature. To do so, a vapor of acetone is co-condensed with magnesium as a catalyst onto a very cold surface.
Photochemistry The outcome of irradiation of acetone is wavelength dependent. At short wavelengths (<290 nm), carbon monoxide and methyl radicals are produced in high quantum yield:
At wavelengths >290 nm, the acetyl radical is produced:
The latter process is relevant to the atmospheric chemistry of acetone.
Catabolism Acetone can then be metabolized either by CYP2E1 via methylglyoxal to D-lactate and pyruvate, and ultimately glucose/energy, or by a different pathway via propylene glycol to pyruvate, lactate, acetate (usable for energy) and propionaldehyde.
Uses About a third of the world's acetone is used as a solvent, and a quarter is consumed as acetone cyanohydrin, a precursor to methyl methacrylate.
Chemical intermediate Acetone is used to synthesize methyl methacrylate. It begins with the initial conversion of acetone to acetone cyanohydrin via reaction with hydrogen cyanide (HCN):
In a subsequent step, the nitrile is hydrolyzed to the unsaturated amide, which is esterified:
The third major use of acetone (about 20%) is synthesizing bisphenol A. Bisphenol A is a component of many polymers such as polycarbonates, polyurethanes, and epoxy resins. The synthesis involves the condensation of acetone with phenol:
Many millions of kilograms of acetone are consumed in the production of the solvents methyl isobutyl alcohol and methyl isobutyl ketone. These products arise via an initial aldol condensation to give diacetone alcohol.
Condensation with acetylene gives 2-methylbut-3-yn-2-ol, precursor to synthetic terpenes and terpenoids.
Solvent Acetone is a good solvent for many plastics and some synthetic fibers. It is used for thinning polyester resin, cleaning tools used with it, and dissolving two-part epoxies and superglue before they harden. It is used as one of the volatile components of some paints and varnishes. As a heavy-duty degreaser, it is useful in the preparation of metal prior to painting or soldering, and to remove rosin flux after soldering (to prevent adhesion of dirt and electrical leakage and perhaps corrosion or for cosmetic reasons), although it may attack some electronic components, such as polystyrene capacitors.
Although itself flammable, acetone is used extensively as a solvent for the safe transportation and storage of acetylene, which cannot be safely pressurized as a pure compound. Vessels containing a porous material are first filled with acetone followed by acetylene, which dissolves into the acetone. One litre of acetone can dissolve around 250 litres of acetylene at a pressure of .Mine Safety and Health Administration (MSHA) – Safety Hazard Information – Special Hazards of Acetylene . Msha.gov. Retrieved on 2012-11-26.History – Acetylene dissolved in acetone . Aga.com, Retrieved on 2012-11-26 Acetone is used as a solvent by the pharmaceutical industry and as a denaturant in denatured alcohol. Acetone is also present as an excipient in some pharmaceutical drugs.Inactive Ingredient Search for Approved Drug Products, FDA/Center for Drug Evaluation and Research
Lab and domestic solvent