Acetone from phenol

Isopropanol is used in the production of other chemicals such as derivative ketones, isopropylamines, and isopropyl esters. The use of isopropanol in the production of monoisopropylamine for herbicides (primarily glyphosate) continues to be the fastest growing segment (Anonymous 2001b). A minor use for isopropanol is to serve as a feedstock for the production of acetone to meet the demand in excess of the coproduct acetone from phenol production. However, isopropanol is also produced from crude acetone, which is generated as a by-product of propylene oxide manufacture (Anonymous 2001b). 

The yield of acetone from the cumene/phenol process is beUeved to average 94%. By-products include significant amounts of a-methylstyrene [98-83-9] and acetophenone [98-86-2] as well as small amounts of hydroxyacetone [116-09-6] and mesityl oxide [141-79-7]. By-product yields vary with the producer. The a-methylstyrene may be hydrogenated to cumene for recycle or recovered for monomer use. Yields of phenol and acetone decline by 3.5—5.5% when the a-methylstyrene is not recycled (21). 

The economics of acetone production and its consequent market position are unusual. Traditional laws of supply and demand cannot be appHed because supply depends on the production of phenol and demand is controUed by the uses of acetone. Therefore, coproduct acetone from the cumene to phenol process will continue to dominate market supply. DeHberate production of acetone from isopropyl alcohol accommodates demand in excess of that suppHed by the phenol process. More than 75% of world and 90% of U.S. production comes from the cumene to phenol process. 

Due to environmental considerations, many phenol plants are equipped with a special water treatment faciUty where acetone and phenol are recovered from the wastewater stream. Also, recovered heavy residue is considered a K-022 waste material by the U.S. EPA and must be properly disposed of by incineration or other means (12). 

Production of a-methylstyrene (AMS) from cumene by dehydrogenation was practiced commercially by Dow until 1977. It is now produced as a by-product in the production of phenol and acetone from cumene. Cumene is manufactured by alkylation of benzene with propylene. In the phenol—acetone process, cumene is oxidized in the Hquid phase thermally to cumene hydroperoxide. The hydroperoxide is spHt into phenol and acetone by a cleavage reaction catalyzed by sulfur dioxide. Up to 2% of the cumene is converted to a-methylstyrene. Phenol and acetone are large-volume chemicals and the supply of the by-product a-methylstyrene is weU in excess of its demand. Producers are forced to hydrogenate it back to cumene for recycle to the phenol—acetone plant. Estimated plant capacities of the U.S. producers of a-methylstyrene are Hsted in Table 13 (80). 

Fig. 1. Catalytic cycle for synthesis of bisphenol A from phenol and acetone in the presence of a dissociated mineral acid (10).

Christopher and Fox have given examples of the way in which polycarbonate resins may be tailor-made to suit specific requirements. Whereas the bis-phenol from o-cresol and acetone (bis-phenol C) yields a polymer of high hydrolytic stability and low transition temperature, the polymer from phenol and cyclohexanone has average hydrolytic stability but a high heat distortion temperature. By using a condensate of o-cresol and cyclohexanone a polymer may be obtained with both hydrolytic stability and a high heat distortion temperature. 

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 ... 

Chemicals Based on Benzene, Toluene, and Xylenes 271 Phenol and Acetone from Cumene... 

Figure 10-6. The Mitsui Petrochemical Industries process for producing phenol and acetone from cumene (1) autooxidatlon reactor, (2) vacuum tower, (3) cleavage reactor, (4) neutralizer, (5-11 ) purification train.

After an initial distillation to split the coproducts phenol and acetone, each is purified in separate distillation and treating trains. An acetone finishing column distills product acetone from an acetone/water/oil mixture. The oil, which is mostly unreacted cumene, is sent to cumene recovery. Acidic impurities, such as acetic acid and phenol, are neutralized hy caustic injection. Figure 10-7 is a simplified flow diagram of an acetone finishing column, and Table 10-1 shows the feed composition to the acetone finishing column. 

Phenol was the 33rd highest-volume chemical. The 1994 U.S. production of phenol was approximately 4 billion pounds. The current world capacity is approximately 15 billion pounds. Many chemicals and polymers derive from phenol. Approximately 50% of production goes to phenolic resins. Phenol and acetone produce bis-phenol A, an important monomer for epoxy resins and polycarbonates. It is produced by condensing acetone and phenol in the presence of HCI, or by using a cation exchange resin. Figure 10-8 shows the Chiyoda Corp. bisphenol A process. 

Figure 10-8. The CT-BISA (Chiyoda Corp.) process for producing bis-phenol A from acetone and phenol. (1) reactor, (2-4) distillation columns, (5) phenol distillation column, (6) crystallizer, (7) solid/liquid separator, (8) prilling tower.

Epoxy resins are widely used in high-strength adhesives, corrosion-resistant coatings, and corrosion-resistant pipes and tanks. The simplest starting material for these thermoset polymers is made from phenol, acetone (to bisphenol A), and epichlorohydrin. 

CT-BISA [Chiyoda Thoroughbred bisphenol-A] A catalytic process for making Bisphenol-A from phenol and acetone. The catalyst is an acidic ion-exchange resin. The product is used for making polycarbonate resins. Developed and offered by Chiyoda Corporation, Japan. The first plant was operated in Tobata, Japan, in 1997. 

We have found several examples in which adjacent cationic charge centers are shown to activate carboxonium electrophiles. A convenient method for studying this activation is through the use of the hydroxyalkylation reaction, a commercially important, acid-catalyzed condensation of aldehydes and ketones with arenes.10 It is used for example in the synthesis of bis-phenol A from acetone and phenol (eq 6). While protonated acetone is able to react with activated arenes like phenol, it is not capable of reacting with less nucleophilic... 

Delaney JL, Hughes TW. 1979. Source Assessment Manufacture of Acetone and Phenol from Cumene. Prepared by Monsanto Research Corp., Dayton, OH. EPA-600/2-79-019D. NTIS PB80-150592, 500. 

Autoxidation. Self-catalyzed oxidation in the presence of air. Autoxidation can be initiated by heat, light, or a catalyst. The commercial production of phenol and acetone from cumene is autoxidation. Other examples include the degradation of polymers exposed to sunlight for long periods of time gum formation in lubricating oils and gasoline and the spoilage of fats. 

Presently there are two processes that make acetone in large quantities. The feedstock for these is either isopropyl alcohol or cumene. In the last few years there has been a steady trend away from isopropyl alcohol and toward cumene, but isopropyl alcohol should continue as a precursor since manufacture of acetone from only cumene would require a balancing of the market with the co-product phenol from this process. 

The major manufacturing process for making phenol was discussed in Chapter 10, Section 4, since it is the co-product with acetone from the acid-catalyzed rearrangement of cumene hydroperoxide. The student should review this process. It accounts for 95% of the total phenol production and has dominated phenol chemistry since the early 1950s. But a few other syntheses deserve some mention. 

Table 11.2 outlines the uses of phenol. We will consider the details of phenol uses in later chapters. Phenol-formaldehyde polymers (phenolics) have a primary use as the adhesive in plywood formulations. We have already studied the synthesis of bisphenol A from phenol and acetone. Phenol s use in detergent synthesis to make alkylphenols will be discussed later. Caprolactam and aniline are mentioned in the following sections in this chapter. 

Kennedy and Stock reported the first use of Oxone for many common oxidation reactions such as formation of benzoic acid from toluene and of benzaldehyde, of ben-zophenone from diphenyhnethane, of frawi-cyclohexanediol Ifom cyclohexene, of acetone from 2-propanol, of hydroquinone from phenol, of e-caprolactone from cyclohexanone, of pyrocatechol from salicylaldehyde, of p-dinitrosobenzene from p-phenylenediamine, of phenylacetic acid from 2-phenethylamine, of dodecylsulfonic acid from dodecyl mercaptan, of diphenyl sulfone from diphenyl sulfide, of triphenylphosphine oxide from triphenylphosphine, of iodoxy benzene from iodobenzene, of benzyl chloride from toluene using NaCl and Oxone and bromination of 2-octene using KBr and Oxone . Thus, they... 

If radicals diffuse from the solvent cage, fragmentation products are formed. Abstraction of hydrogen from the solvent by a phenoxy radical results in phenol, which can almost always be observed among the photoproducts of aryl esters in solution. Chemical evidence for the reaction of phenoxy radical with solvent is the formation of nearly stoichiometric amounts of 4-methyI-phenol and acetone from the irradiation of 4-methylphenyl benzoate (60) in isopropyl alcohol.34... 

Raspberry ketone is prepared by alkali-catalyzed condensation of the alkali salt of 4-hydroxybenzaldehyde and acetone, followed by selective hydrogenation of the double bond in the resulting 4-hydroxybenzalacetone. Other syntheses start from phenol which is converted into 4-(4-hydroxyphenyl)-2-butanone with methyl vinyl ketone (e.g., in the presence of phosphoric acid) [179] or with 4-hydroxy-2-butanone in the presence of concentrated sulfuric acid [180]. 

In addition to the construction industry, phenol has many other applications. It is used in pharmaceuticals, in herbicides and pesticides, and as a germicide in paints. It can be used to produce caprolactam, which is the monomer used in the production of nylon 6. Another important industrial compound produced from phenol is bisphenol A, which is made from phenol and acetone. Bisphenol A is used in the manufacture of polycarbonate resins. Polycarbonate resins are manufactured into structural parts used in the manufacture of various products such as automobile parts, electrical products, and consumer appliances. Items such as compact discs, reading glasses, sunglasses, and water bottles are made from polycarbonates. 

In addition to the established large volume products already mentioned, other plastic materials are known to be under study or have been introduced so recently that their markets have not been fully developed. It seems certain that products such as polyethylene terephthalate and polyacrylonitrile fibers will attain large volume production. A new type of resin that has appeared very recently is Shell Chemical Co. s Epon series (32), a group of polymers of various molecular weight ranges which are produced from phenol, acetone, and epichlorohydrin. 

This reaction has become industrially important as a large scale process for the production of bisphenol A [2,2-bis(p-hydroxyphenyl)propane] from acetone and phenol. 

The intermediate tertiary carbinol could not be detected (with the exception of bis(trifluoromethyl)(hydroxyphenyl)carbinol from hexafluoro-acetone and phenol [395]) and reacts readily with another molecule of phenol this second stage of the reaction is, in fact, an alkylation of phenol by the tertiary carbinol, or by the carbonium ion formed from it, by a common carbonium ion alkylation mechanism (Sect. 3.3). 

This explosive is prepared from m-cresol by a process entirely similar to that by which picric acid is prepared from phenol. The pure material is readily soluble in alcohol, ether, and acetone, soluble in 449 parts of water at 20° and in 123 parts at 100°, yellow needles from water, m.p 107°. The ammonium sa t, which is sparingly soluble in water, has been used in the composition of certain ammonium nitrate explosives, and it was adopted by the Austrian monarchy under the name of ecrasite as an explosive for shells of large caliber. 

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