Mercuric chloride complexes

Tetrahydrothiophene [110-01-0] M 88.2, m -96 , b 14.5 /10mm, 120.9 /760mm, d 0.997, n 1.5289. Crude material was purified by crystn of the mercuric chloride complex to a constant melting point. It was then regenerated, washed, dried, and fractionally distd. [Whitehead et al. 7 Am Chem Soc 73 3632 7957.] It has been dried over Na2S04 and distd in a vacuum [Roberts and Friend J Am Chem Soc 108 7204 1986]. 

Mercury represents a serious environmental risk, and the study of removal of mercury from wastewater has received considerable attention in recent years. Mercury concentration was usually reduced by deposition on a cathode with high surface area. Removal of mercury is studied using extended surface electrolysis which reduces the level of mercury to below acceptable concentrations of 0.01 ppm in wastes by employing a Swiss roll cell with a cadmium-coated, stainless-steel cathode. An industrial cell with a fluidized bed electrode has also been studied. Graphite, as an efficient porous electrode, has been used to remove traces of mercuric ions form aqueous electrolyte solutions. In order to apply the electrochemical method for some effluents, it is necessary to use sodium hypochlorite to convert elemental mercury and less soluble mercury compounds to water-soluble mercuric-chloride complex ions. 

Yokoyama, M., Ishihara, H., Iwamoto, R., and Tadokoro, H. (1969) Structure of Poly(ethylene oxide) Complexes. III. Poly(ethylene oxide)-Mercuric Chloride Complex. Type II, Macromolecules 2, 184-192. 

Chloride ions react with mercury (II) thiocyanate to form a sparingly dissociating mercuric chloride complex and liberate a stoichiometrically equivalent amount of thiocyanate ions (2CT + Hg(SCN)2 - Hgd2 + 2SCN) die thiocyanate reacts with iron (III) ions, yielding die intensely red ferric thiocyanate complex (SCN + Fe3+ -> Fe(SCN)2+), which is determined at 460 nm. 

The extreme insolubility and high melting points of the mercuric chloride complexes suggest that they are polymeric as illustrated for N P (NHMe)g.2HgCl2 (VII)(Figure 3). A number of polymerio mercury complexes are known(4,.5) ... 

Treatment of the reaction mixture (PPh, + nickelocene) with mercuric chloride (a soft reagent cleaving metal-carbon a-bonds)gave noa-CjHjHg Cl. Nickelocene and triphenylphosphine-mercuric chloride complexes have always been the reaction products 228). 

Mercuric chloride,mercuric bromide, and mercuric acetate form stable, solid complexes with thietanes which melt with decomposition. They are useful in the characterization of thietanes. No difficulty was experienced in the formation of complexes of 3-substituted thietanes even when the substituent was l-butyk but the 2,3-disubstituted thietane 89 did not give an isolable mercuric chloride complex. The superior complexing ability (relative to acyclic sulfides) of thietane was determined by partitioning thietane between heptane and saturated aqueous mercuric acetate. ... 

Mercuric chloride complexes of thietane 1-oxides (1 1) are easily prepared, and, because of their sharp melting points, they are useful derivatives. ... 

Phenanthridine, m.p. 106°-107°, crystallizes readily from petroleum and aqueous ethanol. The long-known mercuric chloride complex (B, HCl, HgClo) provides a convenient means of purification. 

When X = H the reaction goes easily but when X = Cl or Br transfer is more difficult. Bis(2-furyl)arsinic acid does not react, and tris(3-furyl)arsine yields a 1 1 mercuric chloride complex, no cleavage taking place. 

Table 2. Distribution of mercuric chloride complexes as fractions of the total mercury in media of different CP concentrations...

Determination with diphenylcarbazone The chloride ion content of the sample is reacted with the excess of mercuric nitrate reagent. After formation of the mercuric chloride complex, the concentration of the free mercuric ions is detected spectrophotometrically with diphenylcarbazone reagent. The diphenylcarbazone reagent forms a violet-colored complex wi the mercuric ions, with a 560 nm absorbance maximum. So the chloride content of the sample decreases the absorbance of the solution. 

Dimethyltetrazole. To a mixture of 35 g. (0.814 mole) of hydra-zoic acid dissolved in about 500 cc. of benzene and 50 cc. of concentrated sulfuric acid, 15.7 g. (0.27 mole) of acetone is added dropwise with stirring and cooling. Approximately 5 1. of nitrogen is evolved. The acid layer is then diluted with ice and neutralized with sodiiun carbonate, and ethanol is added to precipitate the sodium sulfate. After filtration, the solution is concentrated and the mercuric chloride complex of the reaction product is obtained by adding a cold saturated aqueous solution of mercuric chloride. The addition compound melts at 111°. The free... 

Covington et al. [127], taking into account the disproportionation reaction resulting in formation of mercuric-chloride complexes, reevaluated the standard potential of calomel electrode to = 0.261%N. 

High concentrations of alkali halides interfere with this method. The mercuric chloride complex is not volatile at 100° and can be dried at this temperature without loss. 

Complexes similar to these have been formed from a variety of organic compounds. Blumburg et al. (113) formed a mercuric chloride complex by suspending a film of the polymer in a saturated solution of HgCl2 in dry ethyl ether. The complex had a ratio of one mercuric chloride molecule per four oxyethylene units and was rigid, brittle, and insoluble in water. The complex was also studied by Tadakoro et al. (114), who found that different complexes formed depending on immersion time. Complexes with differing properties have also been formed from bentonite (115), cadmium chloride (112), resorcinol (116), and sodium dodecylsulfate (117). 

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