Detergent alkylates

Vista, Huntsman, and other linear alkylben2ene (LAB) producers feed chlorinated paraffins to an alkylation reactor to produce detergent alkylate without prior separation of the unreacted paraffins. Large amounts of paraffins must be recycled in these processes. 

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. 

A simplified flow diagram for a typical UOP linear detergent alkylation unit is shown in Figure 7. The design of this unit is similar to a unit that produces branched-chain detergent alkylate. 

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

PC = paraffin column DC = detergent alkylate column VE = vacuum ejector. 

Future Developments. The most recent advance in detergent alkylation is the development of a soHd catalyst system. UOP and Compania Espanola de Petroleos SA (CEPSA) have disclosed the joint development of a fixed-bed heterogeneous aromatic alkylation catalyst system for the production of LAB. Petresa, a subsidiary of CEPSA, has announced plans for the constmction of a 75,000 t/yr LAB plant in Quebec, Canada, that will use the UOP / -paraffin dehydrogenation process and the new fixed-bed alkylation process (85). 

Table 3 shows typical properties of linear detergent alkylates produced via AIQ., HP, and new UOP Detal catalyst systems (86,87). 

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). 

Because of their initial commercial success and the industry s growing awareness of environmental issues, soHd acid catalysts are expected to ultimately replace Hquid acid catalysts. Several pubHcations describe the use of soHd acid catalysts for the production of cumene and detergent alkylates (62,85-87,109). 

Table 9. Comparative Summary of Various Batch and Continuous Detergent Alkylate Sulfonation Processes using H2SO45 Oleum, and Gaseous SO,...

Conoco operated a stirred tank Pfaudler glass-lined reactor for the batch SO sulfonation of detergent alkylate. The plant utilized over-the-fence SO converter gas (8% SO ia dry air) having h batch cycles (264). AHied Chemical Company provided details for batch SO sulfonation (265,266)... 

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. 

Aluminium chloride Resin manufacture by polymerization of low molecular-weight hydrocarbons Friedel-Crafts reactions to manufacture detergent alkylate, agrochemicals, drugs Irritation due to formation of HCI with moisture... 

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. 

Typical properties of detergent alkylate are shown in Table 10-2. Detergent manufacturers buy linear alkylbenzene, sulfonate it with SO3, and then neutralize it with NaOH to produce linear alkylbenzene sulfonate (LABS), the active ingredient in detergents ... 

Biodegradable detergent alkylate Alkylation procedure (C,0/,4) -paraffins 134... 

Purifying detergent alkylates Separation of catalyst sludge by intro- 140... 

Purification of detergent alkylates Purification of raw alkylbenzene from red oil with water and alkali 147... 

The initial studies of LSDAs were carried out with oleochemicals because of their structural similarity to soap. However, since the molecular structure of an efficient LSDA is characterized by a bulky hydrophilic polar head attached to a long hydrophobic tail, it is also possible to prepare LSDAs from petrochemicals. Sulfated sulfonamide derivatives of alkylbenzenes, such as commercially available detergent alkylates, were synthesized as follows [17] ... 

R represents an alkyl group derived from tallow and R represents an alkyl group in the Cn-Cl5 range corresponding to commercial detergent alkylates. aLSDR values were determined by the Borghetty-Bergman method [22]. 

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. 

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