Alkanesulfonates manufacture

The specifications of alkanesulfonates manufactured by sulfochlorination and subsequent saponification are shown in Table 8 [14]. 

Alkanesulfonates manufactured by sulfochlorination, such as Mersolates, contain about 0.15 wt % chlorine [34]. In biological treatment systems this AOX content disappears completely. 

Sodium alkanesulfonates for detergent manufacture can also be produced from the free-radical addition of sodium bisulfite and alpha olefins ... 

Due to their favorable solubility, alkanesulfonates are preferred as surfactants in liquid products and concentrates. The recent trend to renewable resources has led to a somewhat reduced use in formulations of household detergents in past years. While some manufacturers have withdrawn these surfactants from, for example, manual dishwashing detergents, others did not. Besides many other industrial applications, alkanesulfonates are one of the most important emulsifiers in vinyl polymerization. 

Table 1 gives the production capacities of known installations for alkanesulfonates according to the two established manufacturing routes. It is noticeable that most alkanesulfonate capacities are located in Europe and some in the Far East. No installation is known in the Americas. 

There are two technical routes to the manufacture of alkanesulfonates sulfoxidation and sulfochlorination [1,2]. The sulfoxidation route is the economically more important one, and new plants are based exclusively on this tech-... 

Remarkably, the first priority in process control of manufacturing alkanesulfonates is not the analysis of surfactants. Important criteria, such as for the sulfoxidation process, are the reactor temperature (30-38°C), the composition of... 

The alkanesulfonates obtained in the manufacturing process are also analyzed regularly to determine, for example, the mono- and disulfonate content. 

To trace the provenience of alkanesulfonates to the technical manufacturing process the content of chloro organics needs to be determined. The presence... 

Alkanesulfonates prove important auxiliaries in the textile and leather industries, both for manufacture of (synthetic) fibers and for textile refinement. Surfactants are also important for finishing of textiles, e.g., ensuring antistatic properties. Some processing steps and the surfactants used are listed in Table 32. An interesting overview of surfactants in the textile industry has been published [96]. 

Alkanesulfonates are widely used as an internal antistatic agent for poly(vinyl chloride) (PVC). Since alkanesulfonates cause hazing of unplasticized PVC in the normally used quantities of 1.0 to 1.5 parts per hundred parts resin (phr), its main use is in the manufacture of opaque PVC-calendered film. To produce transparent unplasticized articles, the addition of alkanesulfonates should not exceed 0.3 phr. Figure 40 shows the antistatic effect of alkanesulfonates in PVC. 

MSA and other lower alkanesulfonic acids are useful for plating of lead, nickel, cadmium, silver, and zinc (409). MSA also finds use in plating of tin, copper, lead, and other metals. It is also used in printed circuit board manufacture. In metal finishing the metal coating can be stripped chemically or electrolytically with MSA. MSA also finds use in polymers and as a polymer solvent and as a catalyst for polymerization of monomers such as acrylonitrile. MSA also finds use in ion-exchange resin regeneration because of the high solubility of many metal salts in aqueous solutions. 

Secondary alkanesulfonates are manufactured by the action of sulfur dioxide and air directly on C14-C18 //-paraffins (a sulfoxidation reaction), and the sulfonate group can appear in most positions on the chain. 

Many organosulfur compounds have major industrial uses. For instance, carbon disulfide and DMSO are important commercial solvents and dithiocarbamates are used in the rubber industry as vulcanisation accelerators long chain alkanesulfonic or arenesulfonic acids are important synthetic detergents. Xanthates are used in the manufacture of rayon (see Chapter 8, p. 135) and cellophane, and many commercial dyes contain sulfonic acid groups (see Introduction, p. 5). Sulfamic acid derivatives such as saccharin (see Chapter 9, p. 162) acesulfame potassium (see Introduction, p. 5) and cydamates (see Chapter 9, p. 162) are valuable artificial sweeteners. 

Methane sulfonic acid is used as an electrolyte for electroplating of tin onto sheet steel, for plating tin and tin/lead alloy onto nickel or other base metal substrates in the manufacture of lead frames and bump-contacts for microelectronic devices.It can also be used for copper deposition during the manufacture of microprocessors. Other alkanesulfonic acids have also found use in electroplating applications. Disodium methanedisulfonate and other alkanedisulfonate salts are used in chrome plating.As discussed previously, several processes for the recovery and recycle of alkanesulfonic acids from spent metal plating baths have been described. 

Figure 7.2 illustrates the main routes for sulfonated or sulfated anionic surfactant manufacture [5]. It appears that paraffin sulfonates or alkanesulfonates (i.e., practically only SAS) are made from linear paraffins produced from kerosene or gas oil. 

SAS are sold as waxy flakes (93% active matter), 60% paste, or 30% aqueous solution. Flakes must be stored in the absence of moisture. The aqueous paste, which tends to undergo segregation on standing, must be homogenized before use. The solution remains homogeneous and can be easily pumped [67]. In western Europe, the sales and captive uses of alkanesulfonates were 75,000 t in 1996 and around 85,000 t in 2005, placing them far behind alkylbenzenesulfonates and alcohol ether sulfates and just after AS [68], The main European manufacturer is Clari-ant (all employ sulfoxidation) [69], whereas Stepan and Witco share the market in the United States. 

Ferreira de la Salles, W., Canselier, J.P. and Gourdon, C., An approach to the manufacture of secondary alkanesulfonates without gaseous reagents. Household and Personal Care Today (suppl. to Chimica... 

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