Foam Separation of Mercury Ion with Chelating Surfactant: The Selectivity of the Removal of Cadmium and Mercury lons with 4-Dodecyldiethylenetriamine

Foam Separation of Metals from Aqueous Thiocyanate/Alcohol Solutions

“…A similar increase of the surface properties of suspensions with increased complexation of the metal by thiocyanate and iodide was found earlier (8, 28). Moreover, Okamoto and Chou (29)(30)(31) reported similar relationships between the formation constants and surface tension of solutions of metals-4-dodecyldiethylenetriamine complexes.…”

Concentration Effects on Separation Selectivity in Foam Fractionation

“…As described in Eq. (15), when the sum of the concentrations of these metallic ions is smaller than that of the surfactant, all metallic ions in particular are complexed with the surfactant and thus there is no competition for surfactant complex formation. Then the bubble formation is controlled by the respective surface tensions of the complexes, and the selectivity for the removal of these ions can be calculated by Eq.…”

“…Since Eqs. (14) and (15) were derived by assuming that the surfactant forms 1: 1 complexes with the metallic ions, the selectivity cannot be obtained directly by using these equations. However, qualitatively, the second terms of Eqs.…”

“…Various polyalkylenepolyamines chelate readily with metallic ions such as Cd, Cu, Hg, and Ni (14). Thus we have applied surfactants containing polyalkylenepolyamines, i.e., 4-dodecyldiethylenetriamine, to remove these Downloaded by [University of Calgary] at 23:33 02 February 2015 metallic ions from aqueous solution by foam fractionation (15,16). It was found that these metallic ions can be removed almost quantitatively from aqueous solution by using this chelating surfactant, even in the presence of a large concentration of certain other metallic ions such as Ca, Mg, and Na.…”

The Use of Haz-Flote to Efficiently Remove Mercury from Contaminated Materials

“…Okamoto and Chou (1975) showed that the removal of mercury ions from aqueous solutions was almost quantitative by chelating the ions with the surfactant 4-dodecyldiethylenetriamine. In another study, the cationic surfactant hexadecyltrimethylammonium bromide was used in a foam fractionation study to remove trace levels of mercury (II) nitro complexes (Miller and Sullivan, 1971).…”