Salinity soap effects

Casualties/personnel Speed in decontamination is absolutely essential. To be effective, decontamination must be completed within 2 minutes after postexposure. However, decontamination after the initial 2 minutes should still be undertaken in order to prevent additional percutaneous absorption of the agent leading to systemic toxicity. Remove all clothing as it may continue to emit "trapped" agent vapor after contact with the vapor cloud has ceased. Shower using copious amounts of soap and water. Ensure that the hair has been washed and rinsed to remove potentially trapped vapor. To be effective, decontamination must be completed within 2 minutes of exposure. If there is a potential that the eyes have been exposed to vesicants, irrigate with water or 0.9% saline solution for a minimum of 15 minutes. 

Denture stomatitis. Coconut soap, associated with 05% sodium hypochlorite, used by patients for 15 days, significantly reduced clinical signs of denture stomatitis and was effective in controlling denture biofilm . Desensitization effect. Saline extract of the dried pollen, administered subcutaneously to 96 allergic adults at variable doses, produced a clinical improvement and decreased IgE levels ". 

Surfactant Mixing Rules. The petroleum soaps produced in alkaline flooding have an extremely low optimal salinity. For instance, most acidic crude oils will have optimal phase behavior at a sodium hydroxide concentration of approximately 0.05 wt% in distilled water. At that concentration (about pH 12) essentially all of the acidic components in the oil have reacted, and type HI phase behavior occurs. An increase in sodium hydroxide concentration increases the ionic strength and is equivalent to an increase in salinity because more petroleum soap is not produced. As salinity increases, the petroleum soaps become much less soluble in the aqueous phase than in the oil phase, and a shift to over-optimum or type H(+) behavior occurs. The water in most oil reservoirs contains significant quantities of dissolved solids, resulting in increased IFT. Interfacial tension is also increased because high concentrations of alkali are required to counter the effect of losses due to alkali-rock interactions. 

Treatment of skin lesions also follows decontamination and removal of clothes. Decontamination should be completed within 15 min after exposure to minimize any systemic effects. Contaminated hair should be shaved off. The decontaminating solutions should be washed off within 3-4 min to prevent additional skin injury. Sodium hypochlorite (5%) or liquid household bleach can be used. If erythema is already present, soap and water are preferred. Blisters should be left intact, but if broken, should be debrided to prevent secondary infection. Cleansing with tap water or saline and the application of dressings is done when needed. Silver sulfadiazine or mafenide acetate can be applied and the wounds treated as burn wounds. Infected skin wounds require antibiotics as appropriate. 

Exposed skin should be washed promptly with soap and water. Dermal application of vitamin E oil preparations may be used for both prophylaxis and treatment of paresthesia. Eor contact with eyes, flush immediately and for an extended period with generous amounts of clean water or saline. Gastric lavage is indicated if patient has ingested a large amount of pyrethroid and can be treated soon after exposure. For ingestion of smaller amounts or if treatment has been delayed, activated charcoal and catharsis are indicated. Seizures can be treated with intravenous benzodiazepines (diazepam or loraze-pam) phenytoin or phenobarbital may be helpful for recurrent seizures. No specific antidotes for pyre-throid-induced neurotoxic effects have been approved for use in humans. Spontaneous recovery usually occurs with mild or moderate intoxication. 

Martin and Oxley (1985) studied the effect of different alkalis on surfactant systems. They showed that the presence of any alkali lowered the optimum salinity of the surfactant system. This phenomenon is caused by two facts (1) alkali can provide electrolytes and (2) alkali reacts with crude oil to generate soap, and soap has lower optimum salinity (see the next section). Martin and Oxley found a linear relationship between the optimum salinity and sodium concentration. The addition of any alkali agents results in a decrease in the optimum salinity of the system. However, alkali anions have very little effect on the phase behavior. 

Based on Eq. 12.1, optimum salinity follows the logarithmic mixing rule. Mohammadi et al. (2008) replaced the ratio of oil to surfactant concentration shown in Figure 12.5 by soap molar fraction and used the more generally effective salinity in the vertical axis. They did so because they could get these values from UTCHEM simulation models. Based on the logarithmic mixing rule, both axes in such activity maps are in logarithmic scales, and the upper and lower boundaries should be linear. 

When an alkali is injected into a reservoir with acidic crnde oil, a fraction of acid components are converted into soap, which helps to solnbilize oil and water into the microemnlsion phase. Figure 12.18 shows the water and oil soln-bilization ratios at different effective salinities, based on the two dehnitions. One dehnition is the ratio of water or oil volume (V or Vo) to the volume of injected synthetic surfactant in the microemulsion phase. The other dehnition is the ratio of water or oil volume (V or Vo) to the total volume of injected... 

TABLE 12.4 Effect of Soap Salinity Limits of Type... 

Effect of Partition Coefficient and Dissociation Constant In the base case, the fraction of petroleum acid converted to soap (A/HA) is only 0.246, and the soap molar fraction is 0.309 (see Table 12.4). These values are affected by the partition coefficient Kd between water and oil and the acid dissociation constant Ka. Now let us see how sensitive these two parameters are. The data in Table 12.5 show that Kd is insensitive, whereas Ka is very sensitive. As Ka is increased, more acid is converted to soap. Accordingly, the soap molar fraction in the total surfactant becomes higher. As Xsoap is increased from the base case, the type III salinity limits are closer to those for the soap, which are lower. Thus, the mixture surfactant system becomes type II. As Xsoap... 

Commercial liquid soap added with L-histidine was found to be more effective than the untreated soap. Similarly sodium-ethylene diamine tetraacetic acid (EDTA) salt or L-histidine added to phosphate buffer saline solution was more effective in cleaning nickel contaminated human skin than the phosphate saline alone. 

Symptomatic measures for the treatment of exposure to trichothecene mycotoxins are modeled after the care of casualties of mustard poisoning.85 Irrigation of the eyes with large volumes of isotonic saline may assist in the mechanical removal of trichothecene mycotoxins, but would have limited useful therapeutic effects. After the skin has been decontaminated, some erythema may appear, accompanied by burning and itching. Most casualties whose skin has been treated with soap and water within 12 hours of exposure will have mild dermal effects these should be relieved by calamine and other lotion or cream, such as 0.25% camphor and methanol. 

K is (. 16 for alkyiben .enesulfonates, about 0.10 for alkyl sulfate and fatty acid strdium soaps, 0,17 for i-alky ammonium salts at low pH, and 0.19 for quaternary H-atky I tri methyl ammonium salts, while k is found to be 0.16 for non ionic. systems. The coetfieicnl of the salinity effect for non ionic surfuciants is small, i.e.. O.l.l and 0.10 (in EON unit per wt9f salt in aqueous phase) respectively for sodium and calcium chloride. 

Phosphorus-containing surfactants exhibit a good solubility in saline solutions, they are insensitive to water hardness, they are able to disperse lime soap, and they act as corrosion inhibitors in acid media. They are also valuable components for obtaining synergistic effects due to the variety of possible molecule structures. However, until now this opportunity has only been seldom used, as can be deduced from the literature. In some fields of application, phosphorus-containing surfactants obviously offer many benefits when compared to other types of surfactants. In such cases, they have been applied to great advantage. 

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