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Cumene products from

For cumene production (from benzene and propene) a new process has been developed in which H-mordenite (with high Si/Al) serves as the catalyst. Here the... [Pg.209]

The reactions for cumene production from benzene and propylene are as follows ... [Pg.1129]

Gumylphenol. -Cumylphenol (PGP) or 4-(1-methyl-l-phenylethyl)phenol is produced by the alkylation of phenol with a-methylstyrene under acid catalysis. a-Methylstyrene is a by-product from the production of phenol via the cumene oxidation process. The principal by-products from the production of 4-cumylphenol result from the dimerization and intramolecular alkylation of a-methylstyrene to yield substituted indanes. 4-Cumylphenol [599-64-4] is purified by either fractional distillation or crystallization from a suitable solvent. Purification by crystallization results in the easy separation of the substituted indanes from the product and yields a soHd material which is packaged in plastic or paper bags (20 kg net weight). Purification of 4-cumylphenol by fractional distillation yields a product which is almost totally free of any dicumylphenol. The molten product resulting from purification by distillation can be flaked to yield a soHd form however, the soHd form of 4-cumylphenol sinters severely over time. PGP is best stored and transported as a molten material. [Pg.66]

The cumene is oxidized to cymene hydroperoxide, which decomposes to cresols and acetone. The process is similar to phenol (qv) production from cumene. [Pg.130]

Although Dow s phenol process utilized hydrolysis of the chlorobenzene, a reaction studied extensively (9,10), phenol production from cumene (qv) became the dominant process, and the chlorobenzene hydrolysis processes were discontinued. [Pg.46]

Cumene production follows the demand for phenol and its derivatives. In 1987, the U.S. cumene demand, estimated at 1.9 million metric tons, was supphed by about 1.8 million metric tons of domestic production imports made up the balance. Based on a trend from 1985 on, the demand is projected to increase at about 3% per year through 1995. [Pg.363]

Other Derivatives and Reactions. The vapor-phase condensation of ethanol to give acetone has been well documented in the Hterature (376—385) however, acetone is usually obtained as a by-product from the cumene (qv) process, by the direct oxidation of propylene, or from 2-propanol. [Pg.416]

By far the preponderance of the 3400 kt of current worldwide phenolic resin production is in the form of phenol-formaldehyde (PF) reaction products. Phenol and formaldehyde are currently two of the most available monomers on earth. About 6000 kt of phenol and 10,000 kt of formaldehyde (100% basis) were produced in 1998 [55,56]. The organic raw materials for synthesis of phenol and formaldehyde are cumene (derived from benzene and propylene) and methanol, respectively. These materials are, in turn, obtained from petroleum and natural gas at relatively low cost ([57], pp. 10-26 [58], pp. 1-30). Cost is one of the most important advantages of phenolics in most applications. It is critical to the acceptance of phenolics for wood panel manufacture. With the exception of urea-formaldehyde resins, PF resins are the lowest cost thermosetting resins available. In addition to its synthesis from low cost monomers, phenolic resin costs are often further reduced by extension with fillers such as clays, chalk, rags, wood flours, nutshell flours, grain flours, starches, lignins, tannins, and various other low eost materials. Often these fillers and extenders improve the performance of the phenolic for a particular use while reducing cost. [Pg.872]

Carboxylic acids are thermally stable. Decarboxylation of carboxylic acids is observed at 600 K and higher in the absence of dioxygen [4], At the same time, the decarboxylation of fatty acids in oxidized cumene was observed at 350 K [71]. The study of C02 production from oxidized acetic, butanoic, isobutanoic, pentanoic, and stearic acids labeled with 14C in the... [Pg.348]

Bisphenol A is manufactured by a reaction between phenol and acetone, the two products from the cumene hydroperoxide rearrangement. The temperature of the reaction is maintained at 50 °C for about 8-12 hr. A sluny... [Pg.176]

AIBN is, however, virtually unaffected by the presence of dithio-phosphates (Table II). Further, with specific reference to the oxidation of the disulfide in Table I, which has no effect on the rate of AIBN-initi-ated autoxidation of cumene (6), it is unlikely that the efficiency of radical production from AIBN increases since this would produce a prooxidant effect in cumene. Thus, the zinc salt inhibitor is being oxidized in competition with the main chain reaction. [Pg.342]

This process competes favorably with benzylic hydrogen abstraction in toluene, less in ethylbenzene, and least in cumene (31). Such reactions do not seem significant in the oxidation of benzene derivatives. However, naphthalene reacts about 20 times as rapidly with phenyl radical as does benzene (16), and radical addition to the naphthalene nucleus may at least partly account for the slow oxidation rate in the methylnapthalenes. Among the minor products from both methylnaphthalene oxidations were compounds of molecular weight 296 ... [Pg.409]

Desorption of similar products from cumene- and propylene-deactivated parent H-mordenite is a result analogous to that of Venuto and Hamilton (3). They found that deactivation of rare earth X (REX) faujasite by alkylation of benzene with ethylene to ethylbenzene resulted in trapped products similar to those for deactivation with ethylene alone. [Pg.611]

Polymerization of olefins from cracked gases today covers a broad range of products from motor fuel to petrochemicals. The petrochemical list is expanding rapidly with many of these products being made from propylene. Figure 1 shows a typical chamber type unit for producing the important petrochemicals, tetramer and cumene. [Pg.225]

Acetone is the ketone used in largest quantity and is produced as a by-product of the manufacture of phenol via cumene. Manufacture from iso-propanol is by the reaction ... [Pg.603]

The selective oxidation of hydrocarbons with dioxygen is of immense industrial importance [ 1 ]. A general problem in this area is to obtain high selectivi-ties, particularly at high substrate conversions. The reasons for this are twofold oxidation can occur at different C-H bonds in a molecule, leading to a low primary selectivity, and the initially formed product is often more reactive than the substrate and is oxidized further, ultimately to carbon dioxide and water, leading to low secondary selectivities. Hence examples of industrial processes tend to involve the oxidation of hydrocarbons in which one particular C-H bond is significantly more reactive, for example, cumene hydroperoxide from cumene, and/or the product is relatively stable towards further oxidation, for example, maleic anhydride from n-butane, phthalic anhydride from o-xylene... [Pg.283]

Commercial plants The first commercial application of this process came onstream in 1996. At present, there are 12 plants operating with a combined capacity exceeding 5.2 million mtpy. In addition, four grassroots plants and an AICI3 revamp are in the design phase. Fifty percent of the worldwide and 75% of zeolite cumene production are from plants using the Badger process. [Pg.46]

Overhead vapor from the CD column (1) is condensed and returned as reflux after removing propane and lights (P). The CD column bottom section strips benzene from cumene and heavies. The distillation train separates cumene product and recovers polyisopropylbenzenes (PIPB) and some heavy aromatics (H) from the net bottoms. PIPB reacts with benzene in the transalkylator (2) for maximum cumene yield. Operating conditions are mild and noncorrosive standard carbon steel can be used for all equipment. [Pg.47]

Yields 100,000 metric tons (mt) of cumene are produced from 65,000 mt of benzene and 35,300 mt of propylene giving a product yield of over 99.7%. Cumene product is at least 99.95% pure and has a Bromine Index of less than 2, without clay treatment. [Pg.47]

In the fractionation section, propane that accompanies the propylene feedstock is recovered as LPG product from the overhead of the depropanizer column (2), unreacted benzene is recovered from the overhead of the benzene column (4) and cumene product is taken as overhead from the cumene column (5). Di-isopropylbenzene (DIPB) is recovered in the overhead of the DIPB column (6) and recycled to the transalkylation reactor (3) where it is transalkylated with benzene over a second zeolite catalyst to produce additional cumene. A small quantity of heavy byproduct is recovered from the bottom of the DIPB column (6) and is typically blended to fuel oil. The cumene product has a high purity (99.96-99.97 wt%), and cumene yields of 99.7 wt% and higher are achieved. [Pg.49]

After being cooled in the heat exchanger, the reactor effluent is fed to a distillation column (Tl). All of the butane and unreacted propylene are removed as overhead product from the column, and the cumene and unreacted benzene are removed as bottoms product and fed to a second distillation column (T2) where they are separated. The benzene leaving the top of the second column is the recycle that is mixed with the fresh benzene feed. Of the propylene fed to the process, 20% does not react and leaves in the overhead product from the first distillation column. The production rate of cumene is 1200 Ibm/h. [Pg.486]

The alkylation of arenes with alkenes such as ethylene and propene are of great commercial interest. Ethylbenzene and isopropylbenzene (cumene), products of the Friedel-Crafts alkylation of benzene with ethylene and propene, respectively, are two of the most important petrochemical raw materials. Roberts and Khalaf have follow the developments made in this vast field up to the early part of this decade. This is evident from the large number of references quoted, most of which describe efforts to evaluate conditions for optimal production in the presence of various catalyst systems. [Pg.304]

Since benzene is the primary product from the cracking of cumene over super-D zeolite catalyst, it is assumed to be the desirable in the present development. The selectivity, S, can be defined as the moles of benzene produced per mole of cumene converted, ie. [Pg.369]

Derivation (1) Friedel-Crafts process with benzene and acetic anhydride or acetyl chloride (2) by-product from the oxidation of cumene (3) oxidation of ethylbenzene. [Pg.10]

Although SPA remains a viable catalyst for cumene synthesis, it has several important limitations 1) cumene yield is limited to about 95% because of the oligomerization of propylene and the formation of heavy alkylate by-products 2) the process requires a relatively high benzene/propylene (B/P) molar feed ratio on the order of 7/1 to maintain such a cumene yield and 3) the catalyst is not regenerable and must be disposed of at the end of each short catalyst cycle. Also, in recent years, producers have been given increasing incentives for better cumene product quality to improve the quality of the phenol, acetone, and especially a-methylstyrene (e.g., cumene requires a low butylbenzene content) produced from the downstream phenol units. [Pg.603]

Small quantities of methanol and ethanol are sometimes added to the C3S in pipelines to protect against freezing because of hydrate formation. Although the beta zeolite catalyst is tolerant of these alcohols, removing them from the feed by a water wash may still be desirable to achieve the lowest possible levels of EB or cymene in the cumene product. Cymene is formed by the alkylation of toluene with propylene. The toluene may already be present as an impurity in the benzene feed, or it may be formed in the alkylation reactor from methanol and benzene. Ethylbenzene is primarily formed from ethylene impurities in the propylene feed. However, similar to cymene, EB can also be formed from ethanol. [Pg.610]


See other pages where Cumene products from is mentioned: [Pg.607]    [Pg.189]    [Pg.607]    [Pg.189]    [Pg.363]    [Pg.107]    [Pg.251]    [Pg.605]    [Pg.70]    [Pg.207]    [Pg.111]    [Pg.111]    [Pg.32]    [Pg.377]    [Pg.111]    [Pg.319]    [Pg.183]    [Pg.366]    [Pg.604]    [Pg.606]   
See also in sourсe #XX -- [ Pg.221 , Pg.222 ]




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