Industrial preparation acetone

PROPENE The major use of propene is in the production of polypropylene. Two other propene-derived organic chemicals, acrylonitrile and propylene oxide, are also starting materials for polymer synthesis. Acrylonitrile is used to make acrylic fibers (see Table 6.5), and propylene oxide is one component in the preparation oi polyurethane polymers. Cumene itself has no direct uses but rather serves as the starting material in a process that yields two valuable industrial chemicals acetone and phenol. 

Prevention of peroxidation of isoprene-acetone mixtures, and other hazards involved in the industrial preparation of synthetic citral, are discussed. 

In older industrial processes, acetone is prepared (1) by passing the vapors of acetic acid over heated lime. In a first step, calcium acetate is... 

The industrial preparation of simple aldehydes and ketones usually involves an oxidation reaction of the related alcohol. Thus, formaldehyde is prepared by oxidation of methanol, and acetone is prepared by oxidation of 2-propanol. 

Amines which do not dissolve in water or dilute acids (diphenyl-amine, phenylnaphthylamine, etc.) are most satisfactorily coupled, in the laboratory, in an organic solvent (alcohol, methyl alcohol, acetone, pyridine, etc.). In industrial preparations, such couplers are emulsified... 

The tri-chlorine substitution product of methane is the common and very important anesthetic chloroform. It may be made by the method referred to, viz., by the direct chlorination of methane. This method is not, however, a practical one. The industrial preparation is from alcohol or acetone, by treatment with chlorine and an alkali. In the reaction with alcohol the chlorine acts, first, as an oxidizing agent, oxidizing the alcohol to aldehyde. The chlorine then acts as a substituting agent forming a tri-chlorine substitution product of the aldehyde. This tri-chlor aldehyde is then decomposed by the alkali and chloroform results. The steps in this reaction have been definitely proven, as follows ... 

A comparison of frozen-thawed cells, acetone-dried cells and a buffer extract of acetone-dried cells showed the order of decreasing activity (on a volumetric broth basis) to be acetone-dried cells > buffer extract > frozen-thawed cells. Despite this observation, we decided to use frozen-thawed cells for our further studies for the following reasons a) the preparation of such an enzyme source is very simple and convenient b) if the process eventually assumes industrial importance, the large amounts of acetone and ether needed to prepare acetone-dried cells or extracts therefrom would be both expensive and a waste-treatment problem. 

A major use of the compound cumene is in the industrial preparation of phenol and acetone in the two-step synthesis, shown below. 

However, for the future industrial apphcations on a large scale, other methods suggested for removal of water may prove to be more practical [Wong et al., 2006 Swatloski et al., 2003]. These alternative methods indude nanofiltration, reverse osmosis, pervaporation, and salting out of the IL. Apparently, the advantage of easy recycling of ILs will promote their industrial application in this field [Cao et aL (2007]. Based on the fact that the IL AmimCl can be effectively recycled after each acetylation, Swatloski et al. (2003) provides a technically feasible and environmentally acceptable method to prepare acetone-soluble cellulose diacetates in one step using relatively cheap comhusk as cellulose resource. 

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). 

The best preparative results from autoxidation are encountered when only one relatively reactive hydrogen is available for abstraction. The oxidation of isopropylbenzene (cumene) is carried out on an industrial scale, with the ultimate products being acetone and phenol ... 

Following the completion of the polymerization process, the beaded polymer is recovered from the suspension mixture and freed from the stabilizer, diluents, and traces of monomers and initiators. For laboratory and small-scale preparation, repeated washings with water, methanol, or acetone are appropriate. Complete removal of the monomer diluent, solvents, and initiator, especially from macroporous resin, may require a long equilibration time with warm methanol or acetone. In industry, this is usually accomplished by stream stripping. 

In the chemical industry, simple aldehydes and ketones are produced in large quantities for use as solvents and as starting materials to prepare a host of other compounds. For example, more than 1.9 million tons per year of formaldehyde, H2C=0, is produced in the United States for use in building insulation materials and in the adhesive resins that bind particle hoard and plywood. Acetone, (CH.3)2C"0, is widely used as an industrial solvent approximately 1.2 million tons per year is produced in the United States. Formaldehyde is synthesized industrial ) by catalytic oxidation of methanol, and one method of acetone preparation involves oxidation of 2-propanol. 

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