Salts titration

Optimal Salinities Phase inversions at optimal salinity were assessed routinely by salt titrations into systems maintained at constant temperature. For the Leonox IOS surfactant system, increasing levels of salinity were necessary to cause the emulsion state to phase invert as the alkane molecular weight increased (Figure 11). Ihe initial conductivity value at the condition where zero salt had been added may in part reflect the salt contamination naturally present within the supplied formulation. Ihe internal olefin sulphonate species again revealed a linear relationship between EACN and optimal salinity as did all ionic formulations under test (see Figures 12 and 13, plus Table III). Ihe estimation of EACN values for both toluene... 

FIG. 3.11 Distribution of PZC values reported for all types of AljOj in the literature. Dark gray columns cip , iep , and salt titration. White columns pH and mass titration. 

AI2O3 7, reagent grade, washed 15-35 salt titration... 

The salt titration method [666] is a modification of the salt addition method. A portion of salt is added to a dispersion, and the ApH is recorded. When ApH > 0, base is added to shift the pH to an even higher value. When ApH < 0, acid is added to shift the pH to an even lower value. Once a constant pH has been established, a new portion of salt is added, and ApH is recorded again. The series of salt additions followed by acid or base additions is continued until ApH = 0. The advantage of the salt titration method as compared with the classical salt addition method is that only one portion of dispersion is used. Thus, PZC determination requires a smaller amount of solid and only one reaction vessel. Moreover, a series of measurements (e.g., at different temperatures or at different concentrations of a nonaqueous co-solvent) can be carried out with the same portion of solid, and effects due to a difference in surface properties between different portions of solid are avoided. The number of consecutive salt additions in the salt titration method is limited, because the sensitivity of ApH to an addition of the same amount of salt decreases as the initial salt concentration increases. 

Continuous drift in pH made it impossible to determine the PZC as CIP or by Salt titration. 

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