Effect of Inorganic Electrolytes

For nonionic amphiphiles, the effects of temperature on the phase behavior are large and the effects of inorganic electrolytes are very small. However, for ionic surfactants temperature effects are usually small, but effects of inorganic electrolytes are large. Most common electrolytes (eg, NaCl)... 

Ben-Taleb, A. et al., Electrokinetic studies of monodisperse hematite particles Effects of inorganic electrolytes and amino acids, Mater. Chem. Phys., 37, 68, 1994. 

Lakatos et al. (1979) studied the effect of inorganic electrolytes on the level of retained polymer in sandpacks. In accordance with other workers (Smith, 1970 Szabo, 1979) they found that the adsorbed amount of HPAM increased with an increase in the salt concentration, and the divalent ions such as Ca ... 

Zhao, Y., Xing, W., Xu, N., and Wong, F.-S. (2005). Effects of inorganic electrolytes on zeta potentials of ceramic microfiltration membranes. Sep. Purif. Technol. 42, 117. 

Neddermeyer, P. A. and Rogers, L. B., Column efficiency and electrolyte effects of inorganic salts in aqueous gel chromatography, Anal. Chem., 41, 94, 1969. 

V. Machon, V. Linek, Effect of salts on the rate of mass transfer across a plane interface between a gas and mechanically agitated aqueous solutions of inorganic electrolytes, Chem. Eng. J. 8 (1974) 53-61. 

The data about the electrophoretic behaviour of bubbles in aqueous electrolytes, the first concerning electrophoretic mobilities and zeta-potential, can be regarded as a main direct source of information about surface charge at solution/air interface. As cited by many earlier authors, the electrokinetic behaviour of a gas bubble in aqueous solutions has been studied for over a century [e.g. 174-181]. However, the mechanism of creation of surface charge and the effect of inorganic salts, etc. are not completely clear. Recently Li and Somasunderan [182,183] and Kelsall et al. [184,185] have reported some new results in this field. 

The difficulty in explaining the effects of inorganic solutes on the physical properties of solutions led in 1884 to Arrhenius theory of incomplete and complete dissociation of ionic solutes (electrolytes, ionophores) into cations and anions in solution, which was only very reluctantly accepted by his contemporaries. Arrhenius derived his dissociation theory from comparison of the results obtained by measurements of electroconductivity and osmotic pressure of dilute electrolyte solutions [6]. 

Arafat et al. [4] studied the effect of the concentration of inorganic electrolyte on adsorption of benzene, toluene and phenol from aqueous solution at pH 11.6 on one commercial and two modified activated carbons and obtained very different results for these three adsorbates. The uptake of benzene was rather insensitive to the ionic strength. The uptake of toluene systematically decreased when the ionic strength increased. Finally the uptake of phenol was enhanced on addition of 0.5 mol dm KCl, but further addition of salt depressed the uptake and with 0.8 mol dm"" KCl the uptake dropped below that observed at low ionic strength. Adsorption of phenol on activated carbons was recently studied by other research groups [12,13], but without emphasis on the possible effects of pH dependent surface charging. 

The effect of the concentration of the potential-determining ions and the counterions on the interface potential of the particles has been discussed earlier in this section. Also, it was stated that the critical flocculation concentrations (CFG) of inorganic electrolytes of different valencies are related to each other in the following manner ... 

Regarding the type of inorganic electrolyte, there was no marked difference in effectiveness between the monovalent cations, but preliminary experiments using SBR latexes with emulsifiers which, in contrast to oleate, do not form insoluble salts with divalent cations, demonstrated that in this case PEO was less effective. Findings in earlier sensitization experiments were similar (29, 30). As to the type of anionic emulsifier, a slight correlation between emulsifier surface activity and agglomeration rate was observed. 

Any inference concerning the effects of a possibly altered molecular structure of water near the solid surfaces in soil clays must proceed from an acquaintance with the structure of liquid water in bulk and in aqueous electrolyte solutions. In this section, the current picture of the molecular arrangement in bulk water is reviewed. In Sec. 2.2, the same is done for aqueous solutions of inorganic electrolytes. These summaries are followed by discussions of the structure of water near the surfaces of phyllosilicates and the effect of these surfaces on the solvent properties of the water molecule. 

The effect of the addition of inorganic electrolytes (NaCI. CaCU. AlCh) to the dispersion tm the potential of nitrofmantoin is shown in Figs. 14 and 15 (59). Concerning the effect of NaCI and CaCF (Fig. 14), no important differences are observed between Smoluchowski and O Brien and White methods of calculation of C. ll can be observed that ICI decreases when the concentration of CaCF is increased in the system, as would be expected due to the phenomenon of... 

Refractometry Refractometry is a quick and reasonably accurate alternative to chemical analysis for serum total protein when a rapid estimate is required. The refractive index of water at 20°C is 1.330 if solute is added to the water, the refractive index of a dilute solution increases linearly and proportionally to the solute concentration at higher concentrations of dissolved solids (50-200gl ), the increase is nearly linear. Temperature affects appreciably the refractive index of a solution, so refracto-meters for clinical use compensate for temperature effects. Serum contains dissolved solids in concentrations of 80-100 gl, most of which are proteins. In the refractometry of serum, it is assumed that the concentration of inorganic electrolytes and nonprotein organic compounds does not vary appreciably from serum to serum and that the differences in the refractive index reflect primarily the differences in protein concentrations. The assumption has been shown to be reliable for clear, nonpigmented samples, but hemolysis, lipemia, icterus, and azotemia produce erroneously high results. The method cannot be used for urine protein measurement because of excess solutes in relation to the protein. 

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