Aluminum chloride-hydrocarbon complex

Isomerization catalysts were developed along two paths—by Friedel-Crafts halide systems or by dual site heterogeneous catalysts, originating with the commercial introduction of platinum-aluminas for catalytic reforming in the 1940,s. The Friedel-Crafts systems (aluminum chloride-hydrocarbon complexes) were used exclusively during the early stages of... 

In certain reactions, such as the isomerization of butane and the alkylation of isoparaffins, problems of handling hydrogen chloride and acidic sludge are encountered. The corrosive action of the aluminum chloride-hydrocarbon complex, particularly at 70 to 100°C, has long been recognized and various reactor liners have been found satisfactory. 

Fig. 10. Distribution of aluminum chloride between pentane and aluminum chloride-hydrocarbon complex. Temperature, 212°F.

Fig. 27. Example of corrosion in processes using aluminum chloride-hydrocarbon complex as catalyst. Corrosion resulting from agitated pool of complex in bottom of line. The penetration rate of 5.3 in./yr. was determined during 455 hours of operation.

By catalytic alkylation with hydrogen fluoride, sulfuric acid, or aluminum chloride-hydrocarbon complexes, all in the liquid phase. 

The experiments were made as follows 72 g. aluminum chloride or its equivalent as aluminum chloride-hydrocarbon complex were placed in the reactor, usually with 11. naphtha, and sealed into the reactor. Hydrogen was added in the higher temperature runs until the total reactor pressure was 41 atmospheres at room temperature. In experiments at 21°, anhydrous aluminum bromide was used as the catalyst in an effort to establish the equilibrium more rapidly. 

Steel Aluminum chloride-hydrocarbon complexes formed during isomerization 0.2-2.0% iodine, hydriodic acid, or hydrocarbon iodide... 

The aluminum chloride is handled, in this case, as an approximately 9% solution in relatively inert molten antimony trichloride the solution has a solidification point of about 170° F. (10). As in the other processes, a small amount of liquid aluminum chloride-hydrogen chloride-hydrocarbon complex is continuously formed. 

Simons (143) in a recent review of catalysis concludes that the catalytic activity of hydrogen fluoride must be related to its high acidity. For reactions in the hydrocarbon phase where the dielectric constant of the medium is too low for free ions, we would have to consider complexes of the type Ar HF and Ar HF BF3 which do not exclude ionic mechanisms. For reactions of methylbenzenes with liquid hydrochloric acid or hydrochloric acid and aluminum chloride, similar complexes might be found, and the existence of HAICI4 or HBF4 as such in the medium is unnecessary for an explanation of catalytic action. 

Many chlorinated hydrocarbons react readily with aluminum in the so-caHed bleeding reaction. A red aluminum chloride—chlorinated hydrocarbon complex is formed. Storage of uninhibited chlorinated solvents in aluminum vessels results in corrosion in a short period of time. Proprietary organic inhibitors permit commercial use of reactive solvents such as 1,1,1-trichloroethane and trichloroethylene for cleaning of aluminum. 

The results of the reductions of some steroidal a,)3-unsaturated ketones have been summarized by Brown. " The carbonyl group is usually reduced to the hydrocarbon, but the behavior of the double bond depends on the structure of the compound undergoing the reduction. Cholest-4-en-3-one gives chol-est-4-ene. Addition of aluminum chloride to a solution of a 4-ene-3,6-dione followed by treatment with LiAIH4 gives the 4-ene-6-one. Steroid 4,6-dien-3-ones yield mixtures of dienes. When the ketone and double bond are in different rings the results become even more complex dienes as well as mono-enes are obtained. 

The polymerization of olefins in the presence of halides such as aluminum chloride and boron fluoride but in the absence of hydrogen halide promoter may also be described in terms of the complex carbonium ion formed by addition of the metal halide (without hydrogen chloride or hydrogen fluoride) to the olefin (cf. p. 28). These carbonium ions are apparently more stable than those of the purely hydrocarbon type the reaction resulting in their formation is less readily reversed than is that of the addition of a proton to an olefin (Whitmore, 18). Polymerization in the presence of such a complex catalyst, may be indicated as follows (cf. Hunter and Yohe, 17) ... 

Treatment with aluminum chloride is one of the few chemical methods applied commercially to lubricants in the past 25 years. Aluminum chloride reacts with the undesirable sludge-forming hydrocarbons the complex reaction product is removed by settling. 

Vinyl chloride can be polymerized by butyllithium, ethyllithium or the complex of butyllithium with triethyl aluminum in hydrocarbon solvents (33). The polymerizations show rather peculiar behaviour for... 

Large discrepancies were found in applying the treatment to the Friedel-Crafts benzoylation of the methylbenzenes in nitrobenzene solution (Brown et al., 1958a). It was suggested that these difficulties arose from the formation of ternary complexes of aluminum chloride, the aromatic hydrocarbon, and the solvent nitrobenzene. This notion was tested by a study of the total and positional rates of acetylation... 

Aluminum chloride is used in the petroleum industries and various aspects of organic chemistry technology. For example, aluminum chloride is a catalyst in the alkylation of paraffins and aromatic hydrocarbons by olefins and also in the formation of complex ketones, aldehydes, and carboxylic acid derivatives. 

Aluminum chloride is not widely used as an alkylation catalyst but when employed, hydrogen chloride is used as a promoter and water is injected to activate the catalyst as an aluminum chloride or hydrocarbon complex. Hydrogen fluoride is used for alkylation of higher-boiling olefins and the advantage of hydrogen fluoride is that it is more readily separated and recovered from the resulting product. 

The predominant product in each case was titanium trichloride (aka "tickle 3"), an active catalyst for olefin polymerization. The preferred cocatalyst was diethyl-aluminum chloride (DEAC). TiCl from eq 3.1 contains co-crystallized aluminum trichloride. TiCl from eq 3.3 may contain small amounts of complexed aluminum alkyl. Products from eq 3.1 and 3.2 were supplied commercially by companies such as Stauffer Chemical and Dart (both now defunct). Catalyst from eq 3.3 was manufactured on site by polyolefin producers, usually in an inert hydrocarbon such as hexane. 

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