Mercury colloidal sulfide

The third method has been employed by Lottermoser for the formation of concentrated solutions of colloidal sulfides. This ingenious method consists in the employment of such salts that the products with HaS will not be highly dissociated. For instance, concentrated solutions of colloidal mercury sulfide were made by the use of mercury cyanide. The HCN formed is of course very weakly dissociated and therefore cannot have a great precipitating effect. He also prepared colloidal copper sulfide by means of copper glycocoll and HjS. 

Traces of sulfides were determined by CSV at pH 10 in the presence of cobalt(II) ions. Cobalt sulfide was accumulated at —0.5 V (versus SCE), probably in the form of colloidal particles occluded into the mercury sulfide layer [73]. In the cathodic scan, CoS catalyzed evolution of hydrogen, which was reflected in the current peak at about —1.6 V. 

Sorption colloid flotation has shown to be capable of quantitatively separating ionic mercury from sea water at levels down to 0.02 gg/1 using a cadmium sulfide collector and octadecyltrimethylammonium chloride as a surfactant. The sea water samples need only to be acidified with hydrochloric acid. For flotation an adjustment to pH 1.0 is crucial. Mercury concentrations generally seemed to decrease with the depth of sea water 99). 

Synonym(s) Colloidal mercury liquid silver mercury, metallic (DOT) quicksilver metallic mercuryb hydrargyrum0 Bichloride of mercury mercury bichloride01 mercury chlorided mercury dichloride mercury perchloride mercury (II) chloride perchloride of mercury corrosive sublimated corrosive mercury chloride dichloromercury Etiops mineral0 mercury sulfide, blackd vermilion Chinese red C.l. Pigment Red 106 C.1.77766° quicksilver vermilion Chinese vermilion red mercury sulfide artificial cinnabar red mercury sulfuretd... 

HgS was not removed by flotation with SOS at any pH but was removed readily with HTA at acid pH values with a residual mercury concentration of 0.1 mg/L at pH 0.8. Adsorbing colloid flotation of mercury with aluminum or ferric hydroxide and SDS was also ineffective. Flotation of mercury with HTA and FeS at pH 9 yielded residual concentrations of about 0.05-0.07 mg/L (die separation b not aflecled strongly by ionic strength). The most effective separation appeared to be adsorbing colloid flotation with copper sulfide and HTA. Thb method is effective at ionic strengths as high as 2.0, b insensitive to large pH variations, and can yield residual mercury concentmtions of 0.005 m L. 

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