Surfactant content

In five pilot plants that can be used to simulate the route of anionic surfactants from the consumer via the effluent purification plant to the receiving water, possible toxic effects of residual surfactant content and breakdown products of the secondary alkanesulfonates were investigated [102]. As indicators of the effects on living organisms of the effluent in the receiving water, flora and fauna that are frequently encountered in the p-mesosaprobic zone were used as models. The embryo-larval test was also employed as an additional method for the detection of toxic compounds in the water. 

Crude oils contain various amounts of indigenous surface-active agents that stabilize water-in-oil emulsions. Therefore crude oils may stabilize such emulsions. It has been shown that the effectiveness of a dispersant is dependent on both the dispersant type and the specific crude oil [309]. However, there is no apparent correlation between the degree of emulsion-forming tendency of the crude oil, which is a function of the indigenous surfactant content, and the effectiveness of the dispersant. In general, indigenous surfactants in crude oil reduce the effectiveness of the dispersant, but to an unpredictable level. 

Process efficiency, in this study, is defined as the tertiary oil recovery per unit volume of the slug injected. This refers to the efficiency of an oil-rich slug. Economic recovery efficiency varies from slug to slug due to variations in the surfactant content. it should be noted that the micellar slugs were formulated with an effort to keep the cost a minimum. 

A micellar flood was then started with the injection of the micellar slug, polymer buffer, and the drive water in succession, at a rate of 1.3 m/day. Two types of polymers - polyacrylamide polymer (Dow Pusher 700) and Xanthan Gum polymer (Kelzan XC) - were used as the polymer buffers. Sodium chloride brine (1%) was used as the drive water. Effluent was collected and analyzed for surfactant content using the IR and UV techniques. 

Krznaric [799] studied the influence of surfactants (EDTA, NTA) on measurements of copper and cadmium in seawater by differential pulse ASV. Adsorption of surfactants onto the electrode surface were shown to change the kinetics of the overall electrode charge and mass transfer, resulting in altered detection limits. Possible implications for studies on metal speciation in polluted seawater with high surfactant contents are outlined. 

The qualitative and quantitative surfactant contents of a WWTP discharge, surface water, and foam resulting from an overflow drop... 

In a subsequent work Zoller [81] aimed at mapping the country s surface water, seawater and groundwater according to their non-ionic surfactant content. A further objective was to establish the connection... 

Surfactants enable the polymer particles to disperse effectively without coagulation in the mortar and concrete. Thus, mechanical and chemical stabilities of latexes are improved with an increase in the content of the surfactants selected as stabilizers. An excess of surfactant, however, may have an adverse effect on the strength because of the reduced latex film strength, the delayed cement hydration and excess air entrainment. Consequently, the latexes used as cement modifiers should have an optimum surfactant content (from 5 to 30% of the weight of total solids) to provide adequate strength. Suitable antifoamers are usually added to the latexes to prevent excess air entrainment increased dosages causes a drastic reduction in the air content and a concurrent increase in compressive strength [87, 92-94]. 

Mole-% NP-E0. of total surfactant content Adsorbed amount, Q, at the onset of micellization (mole/g) NP-EO O (mg/ml) solution NP-EO,o... 

Miller, C.A. and Ghosh, 0.(1986) Possible mechanism for the origin of lamellar liquid crystalline phases of low surfactant content and their breakup to form isotropic phases. Langmuir, 2(3), 321-9. 

The most common derivative, N-methyl cocoyl taurine has limited solubility and is commercially available as a 30% paste. Formulators should be aware that the figure is typically a solid content, with the surfactant content being 25%, the balance of solids being mainly salt. 

Figure 6. Dependence of the polymerization rate, Rp, on surfactant concentration, S, at constant pH (values shown alongside curves). Recipe as in Figure 1 except the aqueous solution contained 10 g/l. NagSOf and 2.1 g/l. HaHCO,. The NaOH and surfactant content varied.

A series of experiments have been eonducted in an attempt to improve the thermal stability of the Ti-Zr mesoporous mixed oxide prepared Ifom inorganic precursors. The results show that the crystallinity of the Ti-Zr mesoporous mixed oxide depends strongly on the Ti/Zr molar ratio in the gel mixtures, and a better crystalline mesoporous structure can be obtained on the sample with the 1 1 Ti/Zr molar ratio. It is also found that surfactant content, addition of sulfate species and auxiliary organic additive such as DDA, TritonX-lOO, triethanolamine and ethanol would play a key role in tailoring the mesopore structures and improving thermal stability of the obtained materials. In addition, the mixing order of organic surfactants, i.e., CTAB and DDA, also affects the the crystallinity of the product. 

The results demonstrated pronounced variation of the transport rate in different parts of the microemulsions when in contact with water. This variation caused an interface to appear within the oil phase and also gave rise to temporary liquid crystals at high cosurfactant/surfactant content. 

In which W Is minimum water content In weight percent, S Is the surfactant content, also In weight percent while a and b are constants. For the system with pentanol and sodium dodecyl surfate a 0.5 and b - 0.207. 

This means that Increased surfactant content was always accompanied by a minimum Increase of water content according to Equation 3. Plotting the solubility of the polymer In the pentanol/styrene solution when pentanol Is gradually replaced by the surfactant/water combination according to Equation 3 shows the reflection between polymer solubility and the amount of surfactant/water aggregate present (21). In fact, a linear reduction of polymer solubility was found with Increase surfactant/water content. Figure 5. A surfactant concentration of 9.5% accompanied by water to 2.46% would result In zero solubility of the polystyrene. This means that a composition of pentanol/styrene 25/75 dissolves 42% polystyrene but that the polystyrene Is completely Insoluble In a composition 75% styrene, 13% pentanol, 9.5% surfactant and 2.5% water. Or, expressed In a different manner 1 molecule of polymer Is removed for 1.3 molecules of surfactant and 3.3 molecules of water added. 

An anionic mlcroemulslon system was based on blends of monoethanolamlne salts of bilinear dodecyl benzene sulfonic acid and branched pentadecyl o-xylene sulfonic acid. The bilinear structure results from the alkylation of benzene with a linear a-olefin. The former acts as a surfactant hydrophile (H) while the latter acts as a surfactant lipophile (L) at room temperature for the oil and water phases used in this study. The hydrophile tends to form water-continuous emulsions while the lipophile forms oil-continuous emulsions. The hydrophile-lipophile characteristics were varied by changing the weight ratio of H/L from 0.5 to 0.8. Decane was used as the oil phase and 2.0 wt. X NaCl In water as the aqueovis phase. The water-oil ratio was fixed at 95/5 and the total surfactant content was fixed at 2 g/dl. 

When the surfactant content in aqueous solutions of the VNH2VP copolymer is low (0=1), the intramolecular hindrance reaches a maximum. At a further increase in the content of S (dodecyl sulfate), the formation of S associates in solution and the transition of S ions from the polymer into solution becomes the dominant pro-... 

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