LABS linear alkylbenzene sulfonates

Alkylation of benzene using alpha olefins produces linear alkylbenzenes, which are further sulfonated and neutralized to linear alkylbenzene sulfonates (LABS). These compounds constitute, with alcohol ethoxy-sulfates and ethoxylates, the basic active ingredients for household detergents. Production of LABS is discussed in Chapter 10. 

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 ... 

FIG. 8 Reduction in surface tension of 0.05% solutions of linear alkylbenzene-sulfonate-a-olefinsulfonate (LABS-AOS) mixed surfactant system. (From Ref. 3.)... 

DEQ DM DTD MAC EO FADA LAB LAS M MBAS MCPEG Lever s diester quat dialkyldimethyl ammonium ditallow dimethylammonium chloride ethylene oxide fatty acid diethanolamide linear alkylbenzene linear alkylbenzene sulfonate R3S1O0.5 methylene blue active substances mono carboxylated PEG... 

Trace aromatics removal from linear paraffins in the Ciq-Cis range is an important step in producing linear alkylbenzene (LAB) which in turn is used to make linear alkylbenzene sulfonate (LAS) an important constituent of detergents. High purity linear paraffins are required to produce superior detergent properties. For this application, MgY and NaX adsorbents are reported to be effective adsorbents in removing aromatics from Cio-C n-paraffins [265-267]. 

The production of LAB involves the liquid-phase alkylation of benzene with linear monoolefins or alkyl chlorides. Liquid HF is used as catalyst for linear monoolefins. And the A1C13 is used as the catalyst for alkyl chlorides. Nowadays, acidic zeolite catalyst is used for olefin alkylation which generates less waste and reduces manufacture cost. The alkylate is then sulfonated to produce linear alkylbenzene sulfonate for biodegradable detergents. The manufacture of detergents is described in detail in Chapter 27. 

In the mid-1960s, commercial processes were developed for the production of linear paraffins. These could be used as feedstock to produce linear alkylbenzene sulfonates (LAS), a biodegradable alternative to SDBS. " The majority of synthetic detergent plants built after the 1970s were for the production of LABs rather than DDB. Reformulation with LAS started the phaseout of DDB, and by the end of the 1990s, most DDB plants were no longer in operation or had been converted to production of LAB. 

The worldwide annual production of LAB increased from 1.1 million tons in 1980 to 1.8 million metric tons in 1990 and 2.4 million tons in 2000. Linear alkylbenzene sulfonates continue to be one of the most efficient and cost-effective surfactants in the detergent industry. 

During the early 1960s, linear aliphatic olefins, such as a olefins produced via ethylene oligomerization or linear internal olefins produced via catalytic dehydrogenation of linear paraffins, replaced the use of propylene tetramers ia iadustrialized countries, and production of more biodegradable linear alkylbenzene sulfonates (LABS) began (see ADSORPTION, LIQUID SEPARATION) (70). Except ia a few parts of the world, the use of DDES was phased out by 1980. 

A great deal of interest is currently focused on methyl ester sulfonates (MES) from palm and coconut derivatives with the increase in crude oil prices and the resultant increase in the prices of petrochemicals. MES offers an environment friendly and viable alternative to the old workhorse surfactant linear alkylbenzene sulfonic acid/sulfonate (LAS/LABS), which is derived from linear alkylbenzene (LAB). 

Description. Today, the linear alkylbenzene sulfonate is the most important surfactant used. Linear chains are preferred over the branched ones due to their improved biodegradability. The reaction of linear olefins or chlorinated straight-chain paraffins with benzene in the presence of Friedel-Crafts-type catalysts (AICI3 or HF) yields linear alkylbenzene (LAB), the precursor of LAS this raw material can be procured under very attractive commercial conditions. The LAB isomer distribution depends on the type of catalyst selected. Isomers with the phenyl in the 2-position are present at about 20% and 30% in the mixture resulting from HF- and AlCls-catalyzed processes, respectively. 

The approximate breakdown of surfactant consumption by class is shown in Figure 1.2. Six major surfactant types accounted for 60% of the total consumption. The big six are soaps, linear alkylbenzene sulfonates (LABS), alcohol ethoxylates (AE), alkylphenol ethoxylates (APE), alcohol ether sulfates (AES), and alcohol sulfates (AS). 

The linear alkylbenzene sulfonates (LABS) family is probably the world s most important surfactant family, taking into consideration their wide applicability, cost-effectiveness, and overall consumption levels. If raw-materials prices and availability (i.e., normal paraffins and benzene) remain stable, there is Utile reason to expect the situation to change in the near future. If feedstock prices increase significantly, however, alcohol sulfates and related materials derived from fat and vegetable sources may become attractive alternatives. 

Paraffin sulfonates, or secondary n-alkylsulfonates, are mostly a European product prepared by the sulfoxidation of paraffin hydrocarbons with sulfur dioxide and oxygen under ultraviolet irradiation. They are used in applications similar to those of the linear alkylbenzene sulfonates (LABS) discussed below. It has been suggested that the paraffin sulfonates have higher water solubility, lower viscosity, and better skin compatibility than do the LABS of comparable chain length, although any such direct comparison must be qualihed because of the distinctly different chemical and isomeric contents of the two classes of materials. 

Particularly important members of this family are the alkylbenzene sulfonates (ABS) and the linear alkylbenzene sulfonates (LABS). The ABS family, as mentioned earlier, is based on highly branched tetrapropylene alkyl groups that resist biodegradation processes, something that is less of a problem with the linear alkyl analoges. 

Friedel-Crafts technology and zeolite- or other solid catalyst-based processes are currently used for other aromatic alkylations, in particular for the manufacture of linear alkylbenzenes (LABs) made from C10-C14 olefins (Equation 8), or from the corresponding chloroparaffins and benzene, and also to make m- and p-cymene (isopropyltoluene Equation 9). LABs are used for the production of sulfonate detergents, while cymenes lead to m- and p-cresols through a procedure analogous to that used for the cumene-to-phenol process. 

Of all the various surfactants used in detergent formulations, alkylbenzene sulfonates are by far the most widely used. As a result, alkylbenzenes are the most widely used surfactant raw materials. There are two basic types of alkylbenzenes used in surfactant manufacturing linear alkylbenzenes (LAB) and branched alkylbenzenes (BAB). Both types of alkylbenzenes are homolog mixtures. Typical homolog representatives of LAB and BAB are depicted in Figures 2.1 and 2.2, respectively. 

LAS results from the linear alkylbenzene (LAB) sulfonation reaction and its specific chemical composition, as well as application performance, depend on two main factors—the purity of the LAB raw material and sulfonation technique used. 

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