Consumption of surfactants

Also the a-ester sulfonates are less important today. In the Federal Republic of Germany, for example, the total production of surfactants was about 700,000 t/a in 1993. For a more detailed analysis of different types of surfactants, use must be made of data collected before the unification of Germany. In 1988 the consumption of surfactants in detergents was about 227,500 t/a, the consumption of anionic surfactants was about 116,000 t/a and less than 1000 t/a of a-sulfo fatty acid esters [5] (the values refer to German Detergent Law). 

The total world consumption of surfactants as agricultural adjuvants was estimated to be 60,000 t in 1993 [10], and this figure is expected to continue to increase as more concerted efforts are made to reduce the amounts of crop protection chemicals used. Indeed, whilst figures in 1995 showed the worldwide adjuvant market valued at only 3% that of the corresponding agrochemicals, the increase in use per annum was 5% as compared with 1.5% per annum for the agrochemicals [9]. 

WORLDWIDE CONSUMPTION OF SURFACTANTS, even excluding soaps, is now measured in billions of pounds. In the United States alone, surfactants are a multibillion dollar industry, with hundreds of different types used in industrial and consumer products for a multitude of different purposes. 

The worldwide consumption of surfactants in 2003 is shown in Table 36.5. In many parts of the world, soap is still the primary surfactant for textile washing and personal care. Synthetic detergents are widely used in the devolved regions of the world including North America, Western Europe, and Japan. Anionic surfactants dominate the world surfactant market. Common anionic surfactants include LAS, AS, and AES. The second largest class of surfactants is the nonionics of which AE and APE are most common. The use of APE is in decline because of concerns with biodegradability and endocrine disruption. Quats are commonly used in antibacterial formulations because of their ability to lyse the cell membrane of... 

Consumption of surfactant may occur upon adsorption if it tends to dissolve in the other phase, which may be a slow process. 

The effective enrichment of ores and minerals by flotation, including the possibility of separating materials with similar chemical properties, is achieved by employing a variety of different surfactants which selectively hydrophobize the surface of minerals that undergo flotation, and hydrophilize the surface of those that do not (or the other way around). Due to the relatively small surface area of the minerals treated, the consumption of surfactant-based flotation aids can be as low as 100 grams per tonne, which allows one to use rather complex and expensive surfactants in fine tuning the surface properties of the minerals separated. 

Such properties thus enable their use in detergents, cleaners, dishwashing formulations, and also in bodycleansing products. They are particularly useful in dry cleaner, formulations, e.g. for carpet cleaners. The world-wide consumption of o -olefinesulfonates in the last decade was of the order of 85 000 t, that is 1.5% of the total consumption of surfactants. 

Table 22.1. Production and consumption of surfactants in Western Europe according to Comite Europeen des Agents de Surface et de leurs Intermediares Organiques (CESIO) (in 1000 t - as 100% active)...

By far the largest consumption of surfactants world-wide is for washing and cleaning purposes. This application... 

In western Europe, the consumption of surfactants in 2005 amounted for 2.9 million tons. This amount is distributed to the different surfactant classes as follows [8] ... 

Figure 5.10 Krafft-CMC relationship for two families of surfactants (black sodium alkyl sulfates, white sodium alkyl sulfonates). A balance is needed to satisfy as much as possible all parameters involved, including low CMC (less consumption of surfactant) - not very high temperatures (thus saving of energy) - rather fast cleaning (thus avoiding very heavy surfactant molecules that diffuse slowly from solutions). A chain-length of about 12-14 (maybe upto 16) carbon atoms fulfils in many cases most of these conditions. Reprinted from Kontogeorgis and Folas (2010), with permission from john Wiley Sons, Ltd...

The consumption of surfactants in Western Europe is estimated to be more than 1 million tons/year. As shown in Fig. 10, about 60% of this quantity are anionic surfactants (above all LAS), and the remainder is divided into about V4 of nonionics and % of cationics or amphoteric surfactants. 

In addition to the catching-up demand of the developing countries, a further future increase in the world-wide consumption of surfactants should also be expected. In general, a greater increase is expected in nonionics. This trend is perhaps further reinforced by the necessity of replacing a part of the phosphates in detergents. 

By approximate calculation the consumption of surfactants in the catchment area of the Rhine (about 40 million inhabitants) were compared with the anionic and nonionic surfactants actually found [83]. Of the substance originally used, only 1.2% of the anionic surfactants and 2.7% of the nonionic surfactants were still present in the Rhine at Emmerich, upstream of the Dutch border, according to the mean values of the concentrations in 1979. Considering relevant loads, the figures indicate 0.68% of the anionic surfactants consumed and 1.59% of the nonionic surfactants consumed. 

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