Surfactants consumption

There is an increasing demand for mild, nontoxic, biodegradable products made from renewable or natural raw materials. Energy questions are becoming more important in relation to the production and use of surfactant containing products. Consumers are demanding products that function well at lower temperatures, as well as multifunctional products that allow them to save money and reduce the amounts of chemicals added to wastewater. 

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. 

There do exist some concerns and questions about the overaU long-term ecological impact of LABS. Of particular importance are the following  

LABS are not easily biodegradable under anaerobic conditions. 

Limited data are available on what happens when dissolved LABS enters a waterway and what its effects on adsorption and sedimentation wiU be. 

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The greatest amount of surfactant consumption is in packaged soaps and detergents for household and industrial use. The remainder is used in processing textiles and leather, in ore flotation and oil-drilling operations, and in the manufacture of agricultural sprays, cosmetics, elastomers, food, lubricants, paint, pharmaceuticals, and a host of other products. 

Council of European Surfactant Producers (CESIO) statistics [10] indicate a total surfactant production of 2.4 million tons in Europe for 1999, which were distributed in the categories shown in Table 1.5. Other information sources [11] indicate a surfactant consumption of 2.1 million tons in Europe for 1998, which compares very well with the CESIO figure. Europe is a net exporter of surfactants and a precise figure of actual European consumption is thus difficult to estimate, although information from CESIO provides data on total sales and captive use. 

The major surfactant families in use in the European market in volume terms are the non-ionics followed by anionic derivatives. A detailed breakdown of the total surfactant consumption for Western Europe can be found in Tables 1.6 and 1.7, which show the estimated proportions for the various uses of surfactants in the European market. Probably the most important final use of surfactants in Europe is in detergent manufacture, as demonstrated by the figures summarised in Table 1.8. 

In Table 1.11, a summary of the estimated world surfactant consumption by regions is presented. The two major consumption areas are Asia and North America followed by Europe. 

Surfactant consumption in Western Europe for the period 1998- 1999, in 103t [10] ... 

In general, the change in surfactant consumption is directly coupled to the usage in detergent products, which makes up about 55% of the entire production. Cleaning applications cover a multitude of fields comprising household detergents, consumer products, personal care... 

Total surfactant consumption for Western Europe in 1998 by type [11]... 

Numerous laboratory sorption studies have been conducted for the most common surfactants non-ionics, such as AE and alkylphenol ethox-ylates (APEOs) anionics such as LAS, secondary alkane sulfonates (SASs) and sodium dodecylsulfates (SDS) and on different natural sorbents [3,8,15-17], Until now, cationic and amphoteric surfactants have received less study than the other types, probably because they represent only 5 and 2%, respectively, of the total surfactant consumption in Western Europe (1998) [18]. 

Figure 1.5 World surfactant consumption by major application area, 2000 (total = 10.5 million metric tonnes).

Figure 1.8 Surfactant consumption in household products, 2000 in the United States.

Figure 1.10 Surfactant consumption in personal care by region, 2000.

There are a number of industrial process areas where surfactants are used and are important as the means by which the process succeeds. Table 1.6 has presented a fairly comprehensive list of industrial applications for surfactants. Surfactant consumption in the industrial area amounted to more than 4.3 million metric tonnes in 2000 and is shown regionally in Figure 1.13. Regionally, North America is the most important market consuming the largest volume of materials. 

Figure 1.13 Surfactant consumption in industrial uses by region, 2000.

TABLE 5.5 The Major Surfactant Consumption by Type Wbrldwide(10 t)[4,22]... 

The rate of surfactant consumption determines the micelle concentration, Cmiceiie- The amount of adsorbed surfactant onto the particle surface is defined as... 

Surfactants are major industrial products with millions of metric tons produced annually throughout the world. Table 1-1 lists surfactant consumption in the United States and Canada for the year 2000. Table 1-1A shows consumption of the various surfactant charge types by percentage Table 1-1B, consumption of the five major types of surfactant by tonnage. 

TABLE 1-1 Surfactant Consumption—United States and Canada, (excluding soap), 2000... 

The anionic category represents the major part of surfactant consumption. Anionic surfactants include linear alkylbenzene sulphonates (LASs), alcohol sulphates or alcohol ethersulphates. The latter compounds have a poor absorption in the UV range, whereas the LASs show a significant absorption (see Chapter 11). Dodecylbenzene sulphonate (DBS) is used as a reference for LAS measurements (standard method) and shows an absorption band at 225 nm (Fig. 14). 

Appendix lOH Possibility of Microbubble Capture from Below, Dynamic Adsorption Layer and Possibility of Decrease of Surfactant Consumption... 

The personal care industry remains traditionally the largest consumer of soaps depending on the region, from 50 to 75 % of the total surfactant consumption accounts for soaps [81], The increase in body shampoo consumption last decades is assumed to alter the soap market slightly. The consumption rate of soap in household and laundry aids is quite modest now and limited essentially by the "old times" detergents, foam-control additives, chlorine-containing alkali cleaners, and metal cutting oils. The sodium salts of rosin acids and wool wax acids are of some importance for technical needs and bar soaps. 

FIGURE 1.3 Percentage of global surfactant consumption by major application area for 2006 based on total sales of 13 million metric tons. (Note - approximately half is produced for captive use by integrated consumer companies.)... 

This cycle occurs because there is always enough monomer, but not enough surfactant, to form micelles that can adsorb initiating radicals. The nonlinear surfactant consumption vs. the linear rate of surfactant input results in oscillations. Surfactant consumption increases rapidly, as many particles are initiated and grow, but the process overshoots the capacity of the surfactant in the aqueous phase to support polymerization. Once the aqueous phase is no longer saturated, no new particles form, but the old ones continue to grow and consume surfactant. When they are washed out of the reactor and the surfactant saturates the aqueous phase again, new particles can form. 

FIG. 1 Surfactant consumption in the United States (1997), estimated from SRI data. Personal care excludes soaps and syndet bar. 

The removal of As by MEUF depends on the As concentration and surfactants, solution pH, ionic strength, and parameters related to membrane operation. The surfactant may account for a large portion of operating costs therefore, the recovery and reuse of the surfactant is a key factor to make the process economically feasible and to avoid secondary pollution. However, the combination of high MWCO membranes and low surfactant concentrations can benefit the overall process economics for the lower membrane area requirement (due to greater flux) and the reduced surfactant consumption. 

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