Benzene detergent alkylates

Most of the industrially important alkyl aromatics used for petrochemical intermediates are produced by alkylating benzene [71-43-2] with monoolefins. The most important monoolefins for the production of ethylbenzene, cumene, and detergent alkylate are ethylene, propylene, and olefins with 10—18 carbons, respectively. This section focuses primarily on these alkylation technologies. 

Fig. 7. UOP linear detergent alkylate process Rx = reactor S = settler HR = HF regenerator HS = HF stripper BC = benzene column ...

Catalysts. Nearly aU. of the industrially significant aromatic alkylation processes of the past have been carried out in the Hquid phase with unsupported acid catalysts. For example, AlCl HF have been used commercially for at least one of the benzene alkylation processes to produce ethylbenzene (104), cumene (105), and detergent alkylates (80). Exceptions to this historical trend have been the use of a supported boron trifluoride for the production of ethylbenzene and of a soHd phosphoric acid (SPA) catalyst for the production of cumene (59,106). 

About 2% of benzene consumed in 1988 was used for the manufacture of straight-chain or branched-chain detergent alkylate. Linear alkane sulfonates (LAS) are widely used as household and laundry detergents. 

The principal use of the alkylation process is the production of high octane aviation and motor gasoline blending stocks by the chemical addition of C2, C3, C4, or C5 olefins or mixtures of these olefins to an iso-paraffin, usually isobutane. Alkylation of benzene with olefins to produce styrene, cumene, and detergent alkylate are petrochemical processes. The alkylation reaction can be promoted by concentrated sulfuric acid, hydrofluoric acid, aluminum chloride, or boron fluoride at low temperatures. Thermal alkylation is possible at high temperatures and very high pressures. 

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. 

Alkylation, In petrochemicals, any reaction involving the thermal or catalytic addition of an olefin to a branch-chain hydrocarbon or aromatic hydrocarbon. The most notable example in petrochemicals is the addition of ethylene or propylene to benzene to produce ethylbenzene or isopropyl benzene (cumene). Other examples include the production of detergent alkylates. 

The large demand for benzene is due to its use as a starting material in the production of polystyrene, acrylonitrile styrene butadiene rubber, nylons, polycarbonates and linear alkyl benzene detergent. All of these final chemical products that are suitable to form into consumer goods have multiple chemical transformations in various industrial processes to obtain them from benzene. Because the production of benzene does not involve a liquid adsorptive process on a zeolite, these processes are not described here but can be found in other sources. However, it is important to note that benzene is typically a large byproduct from an aromatics... 

Chlorinated kerosene fractions, preferably those of highly paraffinic nature, have been widely used as intermediates in the manufacture of so-called keryl benzene detergents. The volume of chlorinated hydrocarbons so used represents an appreciable contribution to the important alkyl aromatic sulfonate detergent output. 

This mixture of chlorododecanes is used to alkylate benzene, thereby giving a mixture of isomeric dodecylbenzenes, called detergent alkylate ... 

Sulfonation of the detergent alkylate gives exclusively the 4-dodecy I benzene-sulfonic acids, which with sodium hydroxide form water-soluble dodecylben-zenesulfonates ... 

Other detergent alkylates which are gaining acceptance are benzene alkylated by pentamer and phenol alkylated by polypropylene, of which trimer is the preferred polymer. The pentadecylbenzene alkylate is sulfo-nated, while the nonylphenol alkylate is further reacted with ethylene oxide, the latter product going into the production of liquid non-ionic detergents. 

The UOP Paeol process for selective long-chain paraffin dehydrogenation to produee linear mono-olefins is shown in Fig. 15 in combination with the UOP detergent alkylation process. The Pacol process consists of a radial-flow reactor and a product recovery section. Worldwide, more than 2 million metric tons per year of linear alkyl benzene is produced employing this process. 

As shown in Fig. 6, the primary detergent alkylation reaction is the alkylation of benzene with the straight chain mono-olefins to yield LAB. 

Hydrogen fluoride is also used in the alkylation of benzene with linear olefins to produce detergent alkylate for sulfonation to produce detergents. This acid is now being replaced in some plants by fluorided silica-alumina catalysts in the U.O.P.-Petresa process.9 This type of catalyst may be applicable to the alkylation of isobutane with butenes. 

A Nafion-silica analogue, which was made by the sol-gel method, gave over 99% conversion in the alkylation of benzene with 1-dodecene to make detergent alkylate (6.7). It was also useful in acylations of aromatic compounds.24... 

Benzene is also alkylated with 1-olefins (e.g., where R is C10H21) to prepare detergent alkylate for sulfonation to make detergents. A UOP/Petresa process, using a fluorided silica-alumina catalyst, gave 92% linear alkylbenzene and 6% branched alkylbenzene at 97% conversion with a cata-... 

Beilstein Handbook Reference) AI3-00435 Alkane Alkylate P 1 Benzene, dodecyl- BRN 1909107 CCRIS 2291 Detergent alkylate Detergent Alkylate No. 2 Dodecane, 1-phenyl- Dodecylbenzene n-Dodecylbenzene EINECS 204-591-8 HSDB 937 Laurylbenzene Marlican Nalkylene 500 NSC 102805 Phenyidodecan Ucane alkylate 12. Liquid mp 3° bp = 328° d = 0.8551 insoluble in H2O. 

Inhibiting Side Reactions. As stated in a preceding section, undesired by-product sulfone formation is pronounced in the mono- and disulfonation of ai matic hydrocarbons such as benzene, toluene, or xylene with SO or strong oleum. The addition of acetic acid (about 5 per cent by weight of the hydrocarbon) inhibits, but does not eliminate, sulfone formation. Sodium sulfate and sodium benzenesulfonate are also said to inhibit sulfone formation from benzene. In sul nating dodecylbenzene detergent alkylate with SO3, sulfone formation does not occur as it does with benzene or toluene, but sulfonic anhydride formation does occur. This objection-... 

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