Naphtha acetic acid from

Until 1992, about 10% of the total acetic acid capacity in the United States was still based on oxidation of acetaldehyde. However, Eastman Chemical, the only domestic producer making acetic acid from acetaldehyde, shut down their unit and put it on standby at that time. As a result, all U.S. production is now by carbonylation of methanol. Some large European producers, such as BP Chemicals, are still using naphtha oxidation for acetic acid, but the amount made by acetaldehyde oxidation is nominal. 

Commercial production of acetic acid has been revolutionized in the decade 1978—1988. Butane—naphtha Hquid-phase catalytic oxidation has declined precipitously as methanol [67-56-1] or methyl acetate [79-20-9] carbonylation has become the technology of choice in the world market. By-product acetic acid recovery in other hydrocarbon oxidations, eg, in xylene oxidation to terephthaUc acid and propylene conversion to acryflc acid, has also grown. Production from synthesis gas is increasing and the development of alternative raw materials is under serious consideration following widespread dislocations in the cost of raw material (see Chemurgy). 

Butane-Naphtha Catalytic Liquid-Phase Oxidation. Direct Hquid-phase oxidation ofbutane and/or naphtha [8030-30-6] was once the most favored worldwide route to acetic acid because of the low cost of these hydrocarbons. Butane [106-97-8] in the presence of metallic ions, eg, cobalt, chromium, or manganese, undergoes simple air oxidation in acetic acid solvent (48). The peroxidic intermediates are decomposed by high temperature, by mechanical agitation, and by action of the metallic catalysts, to form acetic acid and a comparatively small suite of other compounds (49). Ethyl acetate and butanone are produced, and the process can be altered to provide larger quantities of these valuable materials. Ethanol is thought to be an important intermediate (50) acetone forms through a minor pathway from isobutane present in the hydrocarbon feed. Formic acid, propionic acid, and minor quantities of butyric acid are also formed. 

Although acetic acid and water are not beheved to form an azeotrope, acetic acid is hard to separate from aqueous mixtures. Because a number of common hydrocarbons such as heptane or isooctane form azeotropes with formic acid, one of these hydrocarbons can be added to the reactor oxidate permitting separation of formic acid. Water is decanted in a separator from the condensate. Much greater quantities of formic acid are produced from naphtha than from butane, hence formic acid recovery is more extensive in such plants. Through judicious recycling of the less desirable oxygenates, nearly all major impurities can be oxidized to acetic acid. Final acetic acid purification follows much the same treatments as are used in acetaldehyde oxidation. Acid quahty equivalent to the best analytical grade can be produced in tank car quantities without difficulties. 

About half of the wodd production comes from methanol carbonylation and about one-third from acetaldehyde oxidation. Another tenth of the wodd capacity can be attributed to butane—naphtha Hquid-phase oxidation. Appreciable quantities of acetic acid are recovered from reactions involving peracetic acid. Precise statistics on acetic acid production are compHcated by recycling of acid from cellulose acetate and poly(vinyl alcohol) production. Acetic acid that is by-product from peracetic acid [79-21-0] is normally designated as virgin acid, yet acid from hydrolysis of cellulose acetate or poly(vinyl acetate) is designated recycle acid. Indeterrninate quantities of acetic acid are coproduced with acetic anhydride from coal-based carbon monoxide and unknown amounts are bartered or exchanged between corporations as a device to lessen transport costs. 

Liquid-phase oxidation of lower hydrocarbons has for many years been an important route to acetic acid [64-19-7]. In the United States, butane has been the preferred feedstock, whereas ia Europe naphtha has been used. Formic acid is a coproduct of such processes. Between 0.05 and 0.25 tons of formic acid are produced for every ton of acetic acid. The reaction product is a highly complex mixture, and a number of distillation steps are required to isolate the products and to recycle the iatermediates. The purification of the formic acid requires the use of a2eotropiag agents (24). Siace the early 1980s hydrocarbon oxidation routes to acetic acid have decliaed somewhat ia importance owiag to the development of the rhodium-cataly2ed route from CO and methanol (see Acetic acid). 

Coumarone—Indene Kesins. These should be called polyindene resins (17) (see Hydrocarbon resins). They are derived from a close-cut fraction of a coke-oven naphtha free of tar acids and bases. This feedstock, distilling between 178 and 190°C and containing a minimum of 30% indene, is warmed to 35°C and polymeri2ed by a dding 0.7—0.8% of the phenol or acetic acid complex of boron trifluoride as catalyst. With the phenol complex, tar acids need not be completely removed and the yield is better. The reaction is exothermic and the temperature is kept below 120°C. When the reaction is complete, the catalyst is decomposed by using a hot concentrated solution of sodium carbonate. Unreacted naphtha is removed, first with Hve steam and then by vacuum distillation to leave an amber-colored resin. It is poured into trays, allowed to cool, and broken up for sale. 

Acetic acid (qv) can be produced synthetically (methanol carbonylation, acetaldehyde oxidation, butane/naphtha oxidation) or from natural sources (5). Oxygen is added to propylene to make acrolein, which is further oxidized to acryHc acid (see Acrylic acid and derivatives). An alternative method adds carbon monoxide and/or water to acetylene (6). Benzoic acid (qv) is made by oxidizing toluene in the presence of a cobalt catalyst (7). 

Di n itr o-8- Hyd roxy 1 -Acetoxy-Naphtha bob (2,4-Dinitro-8-acetoxy-naphthol-(l), acetic acid-r >.7-dinit.ro-8-hvdrnxv-nanhthv14r1 V tf rl f5 7. dinitro-8-hydroxy-naphthyl-(l)-acetate]. H0.(O2N)2C10H4.OCOCH3, mw 292.22, N 9.59%, OB to C02 —149.81%, gold prisms from AcOH, mp 200° (decompn). Sol in ale boiling AcOH. Prepn from 1,8-diacetoxy-naphthalene by reaction with dil nitric acid (d 1.4g/cc) at 25-30°... 

Dinitro-2,2 -dichloroazobenzene. brn-red prisms (from solv naphtha), mp 274°(Ref 1) or red ndls (from benz), mp 265°(Ref 3), mp 275-76° (Ref 4) readily sol in benz mod sol in glac acet acid si sol in acet insol in ale was prepd by oxidization of 4-nitro-2-chloro-aniline with alk Na hypochlorite soln (Ref 1) and in 87% yield by oxidation of 4-nitro-2-chloroaniline with iodosobenzene diacetate at 35°(Ref 5)... 

Acetic Acid. Although at the time of this writing Monsanto s Rh-catalyzed methanol carbonylation (see Section 7.2.4) is the predominant process in the manufacture of acetic acid, providing about 95% of the world s production, some acetic acid is still produced by the air oxidation of n-butane or light naphtha. n-Butane is used mainly in the United States, whereas light naphtha fractions from petroleum refining are the main feedstock in Europe. 

Acetic acid Acetaldehyde or butane or naphthas o2 5 From MeCHO 60 °C, [Co], S = 95% from C4 compounds 190 C, 60bar, [Co], C = 30%, S = 45% Homogeneous, homolytic Hoechst, Rh-Poulenc (MeCHO), Celanese, Hulls (C4 s), Distillers, BP(naphthas) Vinyl acetate, cellulose acetate, AcjO, solvent... 

Butane from natural gas is cheap and abundant in the United States, where it is used as an important feedstock for the synthesis of acetic acid. Since acetic acid is the most stable oxidation product from butane, the transformation is carried out at high butane conversions. In the industrial processes (Celanese, Hills), butane is oxidized by air in an acetic acid solution containing a cobalt catalyst (stearate, naphthenate) at 180-190 °C and 50-70 atm.361,557 The AcOH yield is about 40-45% for ca. 30% butane conversion. By-products include C02 and formic, propionic and succinic acids, which are vaporized. The other by-products are recycled for acetic acid synthesis. Light naphthas can be used instead of butane as acetic adic feedstock, and are oxidized under similar conditions in Europe where natural gas is less abundant (Distillers and BP processes). Acetic acid can also be obtained with much higher selectivity (95-97%) from the oxidation of acetaldehyde by air at 60 °C and atmospheric pressure in an acetic acid solution and in the presence of cobalt acetate.361,558... 

Reserpine is isolated from its plant producers by using a nonaqueous solvent process, using, for example, boiling methanol extraction of the African root Rauwolfia vomitoria. Naturally, these extractions are carried out under countercurrent methods. The methanol extract is concentrated and acidified with 15% acetic acid and then treated with petroleum naphtha to remove impurities. Extraction is made using ethylene dichloride. The solvent is neutralized with dilute sodium carbonate, evaporated to drive off the ethylene dichloride, and further evaporated to crystallize the crude reserpine crystals that are then crystallized. 

Other catalytic reactions carried out in fluidized-bed reactors are the oxidation of naphthalene to phthalic anhydride [2, 6, 80] the ammoxidation of isobutane to mcthacrylonitrilc [2] the synthesis of maleic anhydride from the naphtha cracker C4 fraction (Mitsubishi process [81, 82]) or from n-butane (ALMA process [83], [84]) the reaction of acetylene with acetic acid to vinyl acetate [2] the oxychlorination of ethylene to 1,2-di-chloroethane [2, 6, 85, 86] the chlorination of methane [2], the reaction of phenol with methanol to cresol and 2,6-xylenol [2, 87] the reaction of methanol to gasoline... 

Methoxy-naphtha-l-yl-acetic acid (0.225 mol) was dissolved in a mixture of 700 ml benzene and 300 ml HOAc and Pb(OAc)4 (0.225 mol) added. The mixture heated to 60-70 °C, refluxed 30 minutes, cooled, concentrated, extracted with 200 ml CHjClj. 500 ml Diethyl ether was added causing a creamy white precipitate which was filtered through Celite. The ethereal solution was dried and concentrated from which the product recrystallized when chilled and was isolated. 

Volatile Oils.— Thesc are volatile odoriferous principles found in various parts of numerous plants which arise either as a direct product of the protoplasm or through a decomposition of a layer of the cell wall which Tschirch designates a resinogenous layer. They are readily distilled from plants, together with watery vapor, are slightly soluble in water, but very soluble in fixed oils, ether, chloroform, glacial acetic acid, naphtha, alcohol, benzin and benzol. They leave a spot on paper which, however, soon disappears. They respond to osmic acid, alkannin, Sudan III, and cyanin stains similar to the fixed oils and fats. 

It has been reported that other hydrocarbons, e. g., naphthenic naphthas, may also be suitable for the production of acetic acid [58]. This was studied on a pilot scale but never, apparently, commercialized. A large number of metal ions, both varivalent and non-varivalent, were studied. Feeds ranged from pure to very complex hydrocarbon mixtures. While it is difficult to draw any firm conclusions, it was possible to make significant yields of acetic acid. Manganese-ion catalysts were quite effective they produced higher formic acid/acetic acid ratios than cobalt-ion catalysts, as one would expect. 

Industrial routes to acetic acid have included oxidation of ethanol derived from fermentation, hydrolysis of acetylene, and the oxidation of hydrocarbons such as butane or naphtha. In the late 1950s, the development of the Wacker process (a PdCl2/CuCT-catalyzed oxidation of ethylene) provided a route to acetaldehyde, which could be converted to acetic acid by subsequent oxidation. 

Desulfurization of petroleum feedstock (FBR), catalytic cracking (MBR or FI BR), hydrodewaxing (FBR), steam reforming of methane or naphtha (FBR), water-gas shift (CO conversion) reaction (FBR-A), ammonia synthesis (FBR-A), methanol from synthesis gas (FBR), oxidation of sulfur dioxide (FBR-A), isomerization of xylenes (FBR-A), catalytic reforming of naphtha (FBR-A), reduction of nitrobenzene to aniline (FBR), butadiene from n-butanes (FBR-A), ethylbenzene by alkylation of benzene (FBR), dehydrogenation of ethylbenzene to styrene (FBR), methyl ethyl ketone from sec-butyl alcohol (by dehydrogenation) (FBR), formaldehyde from methanol (FBR), disproportionation of toluene (FBR-A), dehydration of ethanol (FBR-A), dimethylaniline from aniline and methanol (FBR), vinyl chloride from acetone (FBR), vinyl acetate from acetylene and acetic acid (FBR), phosgene from carbon monoxide (FBR), dichloroethane by oxichlorination of ethylene (FBR), oxidation of ethylene to ethylene oxide (FBR), oxidation of benzene to maleic anhydride (FBR), oxidation of toluene to benzaldehyde (FBR), phthalic anhydride from o-xylene (FBR), furane from butadiene (FBR), acrylonitrile by ammoxidation of propylene (FI BR)... 

Acetylene is used in oxyacetylene flame for welding and cutting metals as an illuminant as a fuel for purifying copper, silver, and other metals and in the manufacture of acetic acid, acetaldehyde, and acetylides. It is formed when calcium carbide reacts with water. It is also obtained from cracking of petroleum naphtha fractions. 

Hydrocarbon partial oxidation reactions are highly exothermic but reaction temperatures are normally kept down to prevent by-product formation. Any energy recovered in the form of steam is usually fully utilized in the distillation train and/or other processes which are used to separate the desired product in sufficient purity from the accompanying spectrum of by-products. One process which is a net exporter of energy is the naphtha oxidation process for the manufacture of acetic (ethanoic) acid (section 12.5). The only two other processes which are significant exporters of energy are the manufacture of sulphuric acid from sulphur and the oxidation of ammonia to nitric acid. 

Parkesine). Nitrocellulose is mixed with wood naphtha (a mixture of methanol, acetone, acetic acid, and methyl acetate formed during the distillation of wood) to produce a malleable solid. It is marketed, with little success, as a sculpting material. German chemist Eriedrich Wohler first makes calcium carbide, from which he later obtains acetylene. 

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