Industrial ketones

The two most important industrial ketones are acetone and methyl ethyl ketone. 

The industrial process for preparing the reagent usually permits a little hydrolysis to occur, and the product may contain a little free calcium hydroxide or basic chloride. It cannot therefore be employed for drying acids or acidic liquids. Calcium chloride combines with alcohols, phenols, amines, amino-acids, amides, ketones, and some aldehydes and esters, and thus cannot be used with these classes of compounds. 

Michler s ketone is prepared industrially by the interaction of phosgene (COCl,) and dimethyl aniline. 

The reaction of trivalent carbocations with carbon monoxide giving acyl cations is the key step in the well-known and industrially used Koch-Haaf reaction of preparing branched carboxylic acids from al-kenes or alcohols. For example, in this way, isobutylene or tert-hutyi alcohol is converted into pivalic acid. In contrast, based on the superacidic activation of electrophiles leading the superelectrophiles (see Chapter 12), we found it possible to formylate isoalkanes to aldehydes, which subsequently rearrange to their corresponding branched ketones. 

Many low molecular weight aldehydes and ketones are important industrial chem icals Formaldehyde a starting material for a number of plastics is prepared by oxida tion of methanol over a silver or iron oxide/molybdenum oxide catalyst at elevated temperature... 

A number of aldehydes and ketones are prepared both m industry and m the lab oratory by a reaction known as the aldol condensation which will be discussed m detail in Chapter 18... 

Sasol produces synthetic fuels and chemicals from coal-derived synthesis gas. Two significant variations of this technology have been commercialized, and new process variations are continually under development. Sasol One used both the fixed-bed (Arge) process, operated at about 240°C, as weU as a circulating fluidized-bed (Synthol) system operating at 340°C. Each ET reactor type has a characteristic product distribution that includes coproducts isolated for use in the chemical industry. Paraffin wax is one of the principal coproducts of the low temperature Arge process. Alcohols, ketones, and lower paraffins are among the valuable coproducts obtained from the Synthol process. 

Synthol coproducts include alcohols, ketones, and lower paraffins. They are used mainly as solvents in the paint and printing industries, although some alcohols are blended into fuels. In 1992 Sasol began producing 17,500 t/yr 1-butanol [71-36-3] from 5-07-acetaldehyde [75-07-0] and plaimed to start a plant to produce high purity ethanol [64-17-5] in 1993. Acetone [67-64-1] and methyl ethyl ketone [78-93-3] are two ketone coproducts sold as solvents. 

Chemical Properties. A combination of excellent chemical and mechanical properties at elevated temperatures result in high performance service in the chemical processing industry. Teflon PEA resins have been exposed to a variety of organic and inorganic compounds commonly encountered in chemical service (26). They are not attacked by inorganic acids, bases, halogens, metal salt solutions, organic acids, and anhydrides. Aromatic and ahphatic hydrocarbons, alcohols, aldehydes, ketones, ethers, amines, esters, chlorinated compounds, and other polymer solvents have Httle effect. However, like other perfluorinated polymers,they react with alkah metals and elemental fluorine. 

In the early 1920s Badische Arulin- und Soda-Fabrik aimounced the specific catalytic conversion of carbon monoxide and hydrogen at 20—30 MPa (200—300 atm) and 300—400°C to methanol (12,13), a process subsequendy widely industrialized. At the same time Fischer and Tropsch aimounced the Synth in e process (14,15), in which an iron catalyst effects the reaction of carbon monoxide and hydrogen to produce a mixture of alcohols, aldehydes (qv), ketones (qv), and fatty acids at atmospheric pressure. 

Ketones are an important class of industrial chemicals that have found widespread use as solvents and chemical intermediates. Acetone (qv) is the simplest and most important ketone and finds ubiquitous use as a solvent. Higher members of the aUphatic methyl ketone series (eg, methyl ethyl ketone, methyl isobutyl ketone, and methyl amyl ketone) are also industrially significant solvents. Cyclohexanone is the most important cycHc ketone and is primarily used in the manufacture of y-caprolactam for nylon-6 (see Cyclohexanoland cyclohexanone). Other ketones find appHcation in fields as diverse as fragrance formulation and metals extraction. Although the industrially important ketones are reviewed herein, the laboratory preparation of ketones is covered elsewhere (1). 

Methyl Isobutyl Ketone. Methyl isobutyl ketone (MIBK) (4-methyl-2-pentanone), (CH2)2CHCH2COCH2, is an industrially important solvent which after methyl methacrylate and bisphenol A is the third largest tonnage product obtained from acetone. 

Cyclohexanone is by far the most important industrial cycHc ketone (see Cyclohexanoland cyclohexanone). 

Aromatic ketones of industrial significance include acetophenone, propiophenone, and benzophenone. 

Adipic acid (qv) has a wide variety of commercial uses besides the manufacture of nylon-6,6, and thus is a common industrial chemical. Many routes to its manufacture have been developed over the years but most processes in commercial use proceed through a two-step oxidation of cyclohexane [110-83-8] or one of its derivatives. In the first step, cyclohexane is oxidized with air at elevated temperatures usually in the presence of a suitable catalyst to produce a mixture of cyclohexanone [108-94-1] and cyclohexanol [108-93-0] commonly abbreviated KA (ketone—alcohol) or KA oil ... 

A noteworthy development is the use of KH for complexing alkylboranes and alkoxyboranes to form various boron hydrides used as reducing agents in the pharmaceutical industry. Potassium tri-j -butylborohydride [54575-50-7] KB(CH(CH2)C2H )2H, and potassium trisiamylborohydride [67966-25-0] KB(CH(CH2)CH(CH2)2)3H, are usefiil for the stereoselective reduction of ketones (66) and for the conjugate reduction and alkylation of a,P-unsaturated ketones (67). 

As solvents, the amyl alcohols are intermediate between hydrocarbon and the more water-miscible lower alcohol and ketone solvents. Eor example, they are good solvents and diluents for lacquers, hydrolytic fluids, dispersing agents in textile printing inks, industrial cleaning compounds, natural oils such as linseed and castor, synthetic resins such as alkyds, phenoHcs, urea —formaldehyde maleics, and adipates, and naturally occurring gums, such as shellac, paraffin waxes, rosin, and manila. In solvent mixtures they dissolve cellulose acetate, nitrocellulose, and ceUulosic ethers. 

A three-step process involving the oxidation of acetophenone, hydrogenation of the ketone to a-phenylethanol, and dehydration of the alcohol to styrene was practiced commercially by Union Carbide (59) until the early 1960s. Other technologies considered during the infancy of the styrene industry include side-chain chlorination of ethylbenzene followed by dehydrochlotination or followed by hydrolysis and dehydration. 

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