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Alkylation with hydrocarbons

Improved quality alkylates. With hydrocarbon-continuous dispersions, most of the agitation energy is transferred to the relatively low viscosity hydrocarbon phase. Transfer of reactants to the interfaces would be relatively rapid, probably significantly more rapid than those in acid-continuous dispersions. [Pg.88]

Reactions other than those of the nucleophilic reactivity of alkyl sulfates iavolve reactions with hydrocarbons, thermal degradation, sulfonation, halogenation of the alkyl groups, and reduction of the sulfate groups. Aromatic hydrocarbons, eg, benzene and naphthalene, react with alkyl sulfates when cataly2ed by aluminum chloride to give Fhedel-Crafts-type alkylation product mixtures (59). Isobutane is readily alkylated by a dipropyl sulfate mixture from the reaction of propylene ia propane with sulfuric acid (60). [Pg.199]

Cesium forms simple alkyl and aryl compounds that are similar to those of the other alkah metals (6). They are colorless, sohd, amorphous, nonvolatile, and insoluble, except by decomposition, in most solvents except diethylzinc. As a result of exceptional reactivity, cesium aryls should be effective in alkylations wherever other alkaline alkyls or Grignard reagents have failed (see Grignard reactions). Cesium reacts with hydrocarbons in which the activity of a C—H link is increased by attachment to the carbon atom of doubly linked or aromatic radicals. A brown, sohd addition product is formed when cesium reacts with ethylene, and a very reactive dark red powder, triphenylmethylcesium [76-83-5] (C H )2CCs, is formed by the reaction of cesium amalgam and a solution of triphenylmethyl chloride in anhydrous ether. [Pg.375]

Flowever, information concerning the characteristics of these systems under the conditions of a continuous process is still very limited. From a practical point of view, the concept of ionic liquid multiphasic catalysis can be applicable only if the resultant catalytic lifetimes and the elution losses of catalytic components into the organic or extractant layer containing products are within commercially acceptable ranges. To illustrate these points, two examples of applications mn on continuous pilot operation are described (i) biphasic dimerization of olefins catalyzed by nickel complexes in chloroaluminates, and (ii) biphasic alkylation of aromatic hydrocarbons with olefins and light olefin alkylation with isobutane, catalyzed by acidic chloroaluminates. [Pg.271]

Considerable interest arose during the 1970 s and 1980 s in the use of micro-organisms to produce useful fatty adds and related compounds from hydrocarbons derived from the petroleum industry. During this period, a large number of patents were granted in Europe, USA and Japan protecting processes leading to the production of alkanols, alkyl oxides, ketones, alkanoic adds, alkane dioic acids and surfactants from hydrocarbons. Many of these processes involved the use of bacteria and yeasts associated with hydrocarbon catabolism. [Pg.334]

However, these reactions remain hypothetical, and the mechanism of alkylation of low-valent coordinatively insufficient ions during their interaction with hydrocarbons calls for a detailed study. When the activation by some additives is performed the formation of the active transition metal-carbon bond by oxidative addition is also possible, e.g. in the case of such additives as alkylhalogenides or diazocompounds according to the schemes ... [Pg.205]

Using other alkylated benzene hydrocarbons, e.g., amyl-, hexyl-, octyl-, or nonylbenzene, similar surface-active phosphinic acids are formed by reaction with PC13 in the presence of anhydrous aluminum trichloride. The resulting alkylarylphosphinic acids form stable salts with primary, secondary, or tertiary hydroxy amines or aromatic amines [166,171]. [Pg.587]

Catalytic Condensation Also known colloquially as CATCON. A process for oligomerizing olefins, or alkylating aromatic hydrocarbons with olefins. The catalyst is a solid containing free or combined phosphoric acid. Developed by UOP. [Pg.54]

Detal [Detergent alkylation] A process for making detergent alkylate, i.e., alkyl aromatic hydrocarbons such as linear alkyl benzenes, as intermediates for the manufacture of detergents, by reacting C10-C13 olefins with benzene in a fixed bed of an acid catalyst. Developed by UOP and CEPSA as a replacement for their Detergent Alkylate process, which uses liquid hydrogen fluoride as the catalyst. Demonstrated in a pilot plant in 1991 and first commercialized in Canada in 1996. Offered by UOP. [Pg.85]

Special interest attaches to the cyclic aliphatic hydrocarbons. Cyclopropane can be converted to oligomers by cationic catalysis [75, 76], and these appear to be essentially linear but whether they are really different from the polypropenes formed under the same conditions from propene is not yet settled. The initiation most probably involves formation of a non-classical cyclopropyl ion [77], as in alkylations with cyclopropane [78],... [Pg.132]

A reaction which is rather new and not mentioned in older textbooks is the so-called o-bond metathesis. It is a concerted 2+2 reaction immediately followed by its retrograde reaction giving metathesis. Both late and early transition metal alkyls are prone to this reaction, but for d° early transition metals there is no other mechanism than o-bond metathesis at hand. Many similar reactions such as the reaction of metal alkyls with other HX compounds could be described as if they would follow this pathway, but the use of the term o-bond metathesis is restricted to those reactions in which one reacting species is a metal hydrocarbyl or metal hydride and the other reactant is a hydrocarbon or dihydrogen. In Figure 2.30 the reaction has been depicted. [Pg.48]

Lund and coworkers [131] pioneered the use of aromatic anion radicals as mediators in a study of the catalytic reduction of bromobenzene by the electrogenerated anion radical of chrysene. Other early investigations involved the catalytic reduction of 1-bromo- and 1-chlorobutane by the anion radicals of trans-stilhene and anthracene [132], of 1-chlorohexane and 6-chloro-l-hexene by the naphthalene anion radical [133], and of 1-chlorooctane by the phenanthrene anion radical [134]. Simonet and coworkers [135] pointed out that a catalytically formed alkyl radical can react with an aromatic anion radical to form an alkylated aromatic hydrocarbon. Additional, comparatively recent work has centered on electron transfer between aromatic anion radicals and l,2-dichloro-l,2-diphenylethane [136], on reductive coupling of tert-butyl bromide with azobenzene, quinoxaline, and anthracene [137], and on the reactions of aromatic anion radicals with substituted benzyl chlorides [138], with... [Pg.229]

Chemical radicals—such as hydroxyl, peroxyhydroxyl, and various alkyl and aryl species—have either been observed in laboratory studies or have been postulated as photochemical reaction intermediates. Atmospheric photochemical reactions also result in the formation of finely divided suspended particles (secondary aerosols), which create atmospheric haze. Their chemical content is enriched with sulfates (from sulfur dioxide), nitrates (from nitrogen dioxide, nitric oxide, and peroxyacylnitrates), ammonium (from ammonia), chloride (from sea salt), water, and oxygenated, sulfiirated, and nitrated organic compounds (from chemical combination of ozone and oxygen with hydrocarbon, sulfur oxide, and nitrogen oxide fragments). ... [Pg.239]

In the presence of tellurium tetrachloride, aromatic hydrocarbons are alkylated with reactive alkylating agents such as benzylic or t-butyl alcohols and chlorides. The yields are high with toluene but only moderate for benzene, p-xylene and anisole. Equivalent and catalytic amounts of tellurium tetrachloride, respectively, are required for the alcohols and... [Pg.339]

The mechanism of the photochemical alkylation shows particular characteristics as regards the formation of alkyl radicals, the reaction of these radicals with the heteroaromatic substrates, and the rearomatization of the intermediate products. A variety of alkylating agents (hydrocarbons, alcohols, amines, carboxylic acids, amino acids) have been used for photochemical and y-ray-induced alkylation. " ... [Pg.144]

Recently, alkylation of alkyl aromatic hydrocarbons such as toluene, ethylbenzene, cumene, and xylenes with ethene, propene, and 1,2-diphenylethene was investigated by Kijenski et al. (245), who used superbasic K-MgO and K-AI2O3 catalysts at low temperature at atmospheric and elevated pressures. The reaction kinetics, EPR measurements of adsorbed intermediates, and the effects of poisoning determined by the radical trap TEMPO (2,2,6,6-tetramethyl-l-piperidinyloxyl, free radical) led the authors to conclude that sites are the catalytically active centers. To demonstrate the importance of strong one-electron donor sites (F ) for the alkylation and the inactivity of strong two-electron donor centers, the ethylation of cumene, ethylbenzene, and toluene was carried out with MgO-10%NaOH. On this catalyst, strong basic two-electron donor sites (27 33) were found, along... [Pg.284]

The role of the much discussed "primary reaction" of formation of a C2-hydrocarbon from methanol is then limited to producing a very small amount chemisorbed ethene during the incubation period. This C2 will react easily to C3 via alkylation with methanol. [Pg.285]

Esters and acids from simple carbonylation reactions Alcohols, ethers and esters with higher homologous alkyl groups. Hydrocarbons from hydrogenolysis of the alcohol and its homologs. Ethers from dehydration of the substrate. Esters of the reagent alcohol. s)oiefins from dehydration of the alcohols. Isomeric alcohols. Isomer products (linear/branched 50/50 - 60/40). Only 2-methyl butanol Dimers and trimers of i-butene. [Pg.227]

Upon oxidizing ethene, propene, or isobutene together with aldehydes, alkylated aromatic hydrocarbons, methyl ethyl ketone or other... [Pg.16]


See other pages where Alkylation with hydrocarbons is mentioned: [Pg.50]    [Pg.41]    [Pg.185]    [Pg.50]    [Pg.41]    [Pg.185]    [Pg.9]    [Pg.403]    [Pg.220]    [Pg.96]    [Pg.2077]    [Pg.263]    [Pg.112]    [Pg.48]    [Pg.144]    [Pg.65]    [Pg.222]    [Pg.547]    [Pg.85]    [Pg.273]    [Pg.95]    [Pg.403]    [Pg.95]    [Pg.78]    [Pg.213]    [Pg.223]    [Pg.8]    [Pg.310]    [Pg.245]    [Pg.120]    [Pg.172]   
See also in sourсe #XX -- [ Pg.213 ]




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Alkylation with unsaturated hydrocarbons

Aromatic hydrocarbons with alkyl halides

Hydrocarbon Mixtures with Alkyl Phosphoric Acid Derivatives

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