Mercuric Sulfate Research Articles

Studies on quinoline and isoquinoline derivatives. VIII. Hydration and hydrogenation of ethynyl substituents attached to the pyridine moiety of quinoline and isoquinoline rings.

Studies were carried out on the hydration and hydrogenation of the triple bond in quinoline and isoquinoline derivatives containing an ethynyl substituent linked directly to the pyridine moiety. Fourteen kinds of ethynyl quinolines and isoquinolines such as 2-, 3-, 4-phenylethynylquinoline, 2-, 3-, 4-(1-hexynyl) quinoline, 2-(1-propynyl) quinoline, 1-, 3-, 4-phenylethynylisoquinoline, 1-, 3-, 4-(1-hexynyl) isoquinoline, and 1-(1-propynyl)-isoquinoline were converted into the corresponding acylmethyl derivatives with high selectivity, when they were heated in dilute sulfuric acid in the presence of mercuric sulfate. In all cases, no products due to reverse hydration were isolated. Partial catalytic reduction of the ethynyl linkage of the above compounds is possible, while exhaustive reduction afforded quinolines and isoquinolines with a saturated side chain.

Hydration and hydrogenation of acetylenic side-chains at the 4- or 5-position of isoxazoles.

Hydration of 5-isoxazolyl-phenyl (or -butyl) acetylenes (1a, b) in dilute sulfuric acid in the presence of mercuric sulfate afforded 5-isoxazolylmethyl phenyl (or butyl) ketones (3a, b), predominantly. In contrast, the hydration of 4-isoxazolyl-phenyl (or -butyl)-acetylenes (2a-d) under identical conditions gave 4-isoxazolyl benzyl (or pentyl) ketones (5a-d) as the main products. The structure of one of these products, 3, 5-dimethyl-4-isoxazolyl benzyl ketone (5a), was determined by Beckmann rearrangement. Isoxazoles containing a cis-alkene or alkane chain were obtained by the catalytic reduction of the above acetylenes without cleaving the isoxazole nucleus.

The effect of inorganic and organic mercury on growth kinetics of Nitzschia accicularis W. Sm. and Tetraselmis suecica Butch.

Studies have been made on the toxicities of three inorganic (HgCl2, HgSO4, and NH2HgCl) and two organic (CH3HgCl and phenyl mercuric acetate (PMA)) mercury derivatives on planktonic algae (Nitzschia acicularis W. Sm. and Tetraselmis suecica Butch.) Growth kinetics and flourescence changes were used as criteria for assessing algal-metal responses. Methylmercury chloride was found to be the more toxic form, inhibiting growth of both species at levels of 0.025 ppm Hg. PMA inhibited Nitzschia at the same concentration. Inorganic forms prevent growth of the diatom at 0.15-0.20 ppm Hg. Addition of inorganic mercury at concentrations of 0.05 ppm Hg resulted in reduction of the lag phase, increase in exponential growth rate, or both. Increasing mercury concentrations caused a gradual increase in the lag phase in T. suecica and in N. acicularis only with mercuric sulphate. Populations recovered from this initial effect and started to grow. The effect of inoculum size on mercurial toxicity was tested. The higher concentrations of mercury that still permit growth restricted the chlorophyll fluorescence to the central cellular area and the cells appear slimmed. This effect is highest in concentrations that inhibit growth.

Electrochemical behaviour of the oxide covered antimony

The electrochemical behaviour of the system Sb-oxide layer-0.05 M H 2SO 4 was investigated by impedance, photopolarization and by recording voltammetric characteristics in the presence of the redox couple K 3Fe(CN) 6-K 4Fe(CN) 6 from 1.6 to −0.86 V vs mercury mercurous sulphate electrode. Attention has been concentrated on potentiodynamically formed and stabilized films whose thickness enabled the development of the space charge. It will be shown that the mechanism of charge transfer in the Sb-oxide layer-electrolyte system having a given form of current potential characteristics, is dependent on the semiconducting properties of the oxide layer, which can be modified owing to the breaking of bonds and the formation of new ones. Impedance and photoelectric polarization have proved very sensitive and suitable for the investigation of structural and phase change of the solid phase in situ with potential changes in continuous polarization.

Coordination chemistry of benzoxazole-2-thione. Complexes of some transition metal acetates, tetrafluoroborates, sulphates and nitrates

Abstract Several complexes of cobalt(II), nickel(II), copper(II), copper(I), zinc(II), cadmium(II)and mercury(II) acetate, tetrafluoborate, sulphate and nitrate with benzoxazole-2-thione have been prepared and characterized by chemical analyses, ligand-field spectra, magnetic susceptibility measurements, molecular conductances and vibrational spectra (conventional and far i.r.). In the light of spectroscopic investigation it is possible to distinguish whether the anions present are coordinated to the transition metal ion or are present as free ions. Spectroscopic parameters of the cobbalt(II) and nickel(II) complexes are compared with similar chromophores containing sulphur, oxygen and nitrogen donor atoms. The evidence suggests that the sulphato- and nitrato-derivatives of cobalt and nickel are tetrahedral, the nickel tetrafluoroborato-derivative resulted octahedral, while the nickel acetato-complex and the complexes of the cobalt acetate and tetrafluoroborate resulted square planar and in predominantly planar environment respectively. The zinc, cadmium and mercury derivatives with a 1:2 and 1:3 metal:ligand molar ratio have a tetrahedral symmetry with the exception of[Znbot 2 Ac 2 ] which resulted hexacoordinate with the acetato groups acting as symmetrical chelates. The complexes [ZnbotSO 4 ] and [CdbotSO 4 ] have a linear structure with the sulphate group acting as unidentate with a C 3ν symmetry, polymeric structures with the sulphate anion functioning probably as chelate and of symmetry lower than C 2ν being excluded from the i.r. evidence. Allocation for the possible metal-ligand and metal-anion modes have also been made.

Microdetermination of nitrate by gas chromatography-mass spectrometry technique with multiple ion detector

A simple, sensitive method for the determination of nitrate in water by gas chromatography (GC) and mass spectrometry (MS) with a multiple ion detector (MID) has been developed. The principle of the method is the nitration of 1,3,5-trimethoxybenzene in sulfuric acid. In this medium, nitration is followed by the hydrolysis of the ether groups, yielding a simple nitrobenzene as the final product. This is then analyzed by GC-MS and detected with MID. Hexamethylbenzene serves as an internal standard. The interference of nitrite and chloride is prevented by using sulfamic acid and mercuric sulfate, respectively.

Voltammetric and chronoamperometric investigation of germanium amalgams Part I. Properties of the homogenous amalgam

Using cyclic voltammetry and chronoamperometry with several anodic steps the deposition and particularly the oxidation of germanium from a HMDE was investigated within pH range 4–12 at Ge (IV) concentrations ranging from 4×10−7 M to 1×10−4 M in the absence of ligands capable to form the complex compounds with Ge(IV) in a solution. It was found that the initially formed product of electrodeposition is a homogeneous, usually supersaturated amalgam. Germanium from this amalgam oxidizes at about 1 V (vs. mercury sulphate reference electrode) or after some induction period, the length of which depends on concentration of Ge(0) in mercury, it begins to crystallize forming heterogenous germanium amalgam. Germanium from this heterogenous amalgam oxidizes in a separate voltammetric peak at more positive potentials. The solubility of germanium in mercury was evaluated on the basis of the oxidation current of homogenous amalgam and the value obtained is equal to (2±0.5)×10−7 M i.e. (1.1±0.3)×10−7 wt. %. Applying the Stevens and Shain method the diffusion coefficient of germanium in mercury was found to be (1.32±0.1)×10−5 cm2 s−1.

Voltammetric and chronoamperometric investigation of germanium amalgams: Part I. Properties of the homogenous amalgam

Using cyclic voltammetry and chronoamperometry with several anodic steps the deposition and particularly the oxidation of germanium from a HMDE was investigated within pH range 4–12 at Ge (IV) concentrations ranging from 4×10 −7 M to 1×10 −4 M in the absence of ligands capable to form the complex compounds with Ge(IV) in a solution. It was found that the initially formed product of electrodeposition is a homogeneous, usually supersaturated amalgam. Germanium from this amalgam oxidizes at about 1 V (vs. mercury sulphate reference electrode) or after some induction period, the length of which depends on concentration of Ge(0) in mercury, it begins to crystallize forming heterogenous germanium amalgam. Germanium from this heterogenous amalgam oxidizes in a separate voltammetric peak at more positive potentials. The solubility of germanium in mercury was evaluated on the basis of the oxidation current of homogenous amalgam and the value obtained is equal to (2±0.5)×10 −7 M i.e. (1.1±0.3)×10 −7 wt. %. Applying the Stevens and Shain method the diffusion coefficient of germanium in mercury was found to be (1.32±0.1)×10 −5 cm 2 s −1.

Molten lithium nitratepotassium nitrate eutectic: The reactions of three mercury compounds

The reaction of mercury(I) sulphate, mercury(II) sulphate and mercury(II) oxide in pure lithium nitratepotassium nitrate eutectic and in nitrate solutions containing sodium peroxide, monoxide and hydroxide have been studied and stoichiometries derived. The initial major reaction product of mercury sulphates was green schuetteite, HgSO 4 · 2HgO, which was then converted to brown HgO, or with excess peroxide or monoxide to an easily hydrolysed mercurate compound. With low base concentrations yellow-white and grey sublimates containing mercury(I) and nitrate, were formed from mercury sulphates of both oxidation states.

Effects of mercury on the behaviour and oxygen consumption of Monodonta articulata

The trochid snail Monodonta articulata Lamarck was exposed to mercuric sulphate at concentrations of 0.2, 0.5, 0.8 and 1 ppm Hg++. At 24 h, retraction into the shell was observed in 0.8 and 1 ppm Hg++; this retraction increased in these concentrations at 36 h. Retracted snails died if retained in the solutions, but generally recovered within 24 to 48 h if transferred to uncontaminated sea water. Immersionemersion behaviour and interface activity were studied over 24 h by means of an aktograph; snails in normal sea water spent more time below than above the water surface, and exhibited frequent periods of activity. Exposure to mercuric sulphate at concentration of 0.25, 0.5, 0.8 and 1 ppm Hg++ progressively reduced both the length and frequency of activity periods. From 0.5 ppm Hg++ upwards, emersion periods increased, and immersion periods decreased. Oxygen consumption of snails was measured in sea water and in mercuric sulphate at concentrations of 0.2, 0.5, 0.8 and 1 ppm Hg++. Oxygen consumption decreased significantly with each progressive rise in mercury concentration. It is considered that mercury affects M. articulata by interfering with respiration, initially reducing interface activity, then forcing the snail for longer and longer periods out of the water. Retraction occurs when activity is no longer possible. It is concluded that respiratory and behavioural alterations of this nature would afford a good indicator of the presence of sub-lethal concentrations of pollutants.

Evaluation of zinc sulfate electrolytes by cyclic voltammetry and electron microscopy

A cyclic voltammetric technique has been developed for approximating the quantities of active chemical species present in zinc sulfate electrolytes. The experimental apparatus consisted of a Pyrex “H” cell, an aluminum cathode encased in a Teflon holder, a carbon anode and a mercurous sulfate reference electrode. Voltammograms were obtained using industrial, purified neutral leach solution (Cominco Ltd., Trail, BC) acidified to give a final concentration of 0.77 M Zn++ and 1 M H2SO4. The polarization curves were then evaluated and used as reference standards to compare with results obtained when various organic and inorganic additions were made. The deposit morphologies obtained for short-time cathodic cycles were also studied with the aid of a Scanning Electron Microscope. Changes in concentrations of glue in the 5 to 10 ppm range and of antimony in the 5 to 10 ppb range were detected using the techniques described.

The vibrational spectra of mercury (I) bromate, sulphate, and nitrate dihydrate

AbstractA low‐temperature single‐crystal Raman study of mercury(I) nitrate dihydrate is reported, together with low‐temperature powder Raman and i.r. spectra of the nitrate and of mercury(I) bromate and sulphate. The spectra are given consistent interpretations in terms of factor group analysis. Of note is assignment of ν(HgO) in the 250–265 cm−1 interval for coordinated bromate and sulphate; the demonstration that there is no correlation coupling for ν(HgHg) which consequently appears in the Raman spectra as a single band; and a mercurous ion rotatory mode region ca. 40 cm−1.

Substitution of Cupric Sulfate for Mercuric Oxide as Catalyst for the Kjel-Foss Instrument

Abstract A mixture of cupric sulfate and titanium dioxide and cupric sulfate alone were evaluated as possible catalysts to replace mercuric oxide in the determination of protein nitrogen, using the Kjel-Foss automated instrument. It was necessary to modify the instrument to increase the digestion time from 6 to about 12 min to achieve acceptable protein nitrogen recovery with cupric sulfate as the catalyst. An experimental sample set of nitrogen-containing salts and American Association of Feed Control Officials check feed samples were analyzed with the Kjel-Foss instrument in its standard configuration with mercuric oxide and as modified with cupric sulfate as the catalyst. The average per cent nitrogen, standard deviation, and relative standard deviation with mercuric oxide and cupric sulfate were 10.37 and 10.36, 0.040 and 0.042, and 0.53 and 0.56, respectively. The substitution of cupric sulfate for mercuric oxide is feasible, and it eliminates the use of the potential pollutant, mercury.

Polyethylenimine-Containing Cotton Fabrics

Abstract Polyethylenimine-containing cotton fabrics were prepared by reaction of 1-epoxyethyl-3, 4-epoxycyclohexane with cotton fabric impregnated with polyethylenimine of a moderately high molecular weight. Fabrics with a high unremovable polyethylenimine content and with a different degree of cross-linking were obtained. Adsorption of several heavy metal salts such as mercuric chloride and cupric sulfate by the fabrics was investigated. Adsorption was controlled by polyethylenimine content of the fabric, extent of cross-linking, and the pH of the solution.

Catalysis by mercuric ion of reactions of glycals with water

In the presence of mercuric sulfate, 3,4,6-tri- O-acetyl- d-glucal ( 4), dissolved in 1,4-dioxane-dilute sulfuric acid at room temperature, is rapidly and quantitatively converted into 4,6-di- O-acetyl-2,3-dideoxy- aldelhydo d- erythro- trans-hex-2-enose ( 8). With acetone as the organic component of the solvent, this product is accompanied by the 5,6-di- O-acetyl isomer ( 10). The corresponding, α,β-unsaturated aldehydes ( 12 and 13; 15) are formed in an analogous way from 3,4,6-tri- O-acetyl- d-galactal ( 11) and 3,4-di- O-acetyl- d-arabinal ( 14). Similarly, instead of hydration, d-glucal ( 1) and d-galactal undergo elimination catalyzed by mercuric ion and acid to yield 2-( d- glycero-1,2-dihydroxyethyl)furan ( 3) as the sole product. Possible mechanisms for these transformations are discussed.

Hydration of unsymmetrical acetylenic ?-glycols

Based on the NMR spectral data, secondary-tertiary acetylenic γ-glycols add water under the influence of mercuric sulfate to give the 2-methyl-5,5-dialkyl-4- and 2-methyl-5, 5-dialkyl-3-tetrahydrofuranones in a 1∶1 ratio.

Propriétés chimiques et électrochimiques du mercure dans l'hydrogénosulfate de potassium fondu ( t=220°C, P(H 2O)=0.041 atm)

Summary The chemical and electrochemical properties of mercury have been investigated by voltammetry and potentiometry in molten potassium hydrogenosulphate ( t =220°C, P (H 2 O)=0.041 atm). These studies showed that mercury was corroded in acidic media. The mercurous, Hg 2 2+ , and mercuric, Hg 2+ , ions exist for low pH values, but precipitate in basic media as Hg 2 SO 4 and HgSO 4 . The mercuric sulfate is dissolved in KHSO 4 for higher pH value as Hg(SO 4 ) 2 2− . Equilibrium acid-base constant values and standard potentials are given [p K (Hg 2 2+ , Hg 2 SO 4 (s))=−1.1±0.1; p K (Hg 2+ , HgSO 4 (s))=−0.3±0.1; p K (HgSO 4 (s), Hg-(SO 4 ) 2 2− )=2.8±0.1; E 0 (Hg/Hg(I))=0.178±0.007 V; E 0 (Hg(I)/Hg(II))=0.381±0.010 V] and the potential-pH diagram is deduced.

PHOTOCHEMICAL METHYLATION OF INORGANIC MERCURY IN THE PRESENCE OF SOLID SULFUR

Abstract The photosensitized methylation of inorganic mercury in the presence of solid sulfur was investigated in an aqueous acetic acid solution of mercuric acetate. It was found that the photooxidation of sulfur into sulfate ions coupled with the reduction of mercuric ions and the resulting sulfate ions reacted with mercuric acetate to produce basic mercuric sulfate, a yellow precipitate, which acted as an effective photosensitizer for the methylation.

A potentiometric method for the determination of chloride in boiler waters in the range 0·1 to 10 µg ml–1 of chloride

A potentiometric method for determining chloride in boiler water has been developed, which is based on the potential of a silver-silver chloride wire electrode versus a mercury(I) sulphate reference electrode immersed in a buffered solution of the sample. The method was tested in the range 0·1 to 10·0 µg ml–1 of chloride and the standard deviations of the results at 0·1, 1·76 and 10·0 µg ml–1 of chloride were approximately 0·04, 0·06 and 0·2 µg ml–1 of chloride, respectively. Substances normally present in boiler water do not interfere appreciably but the method is not suitable if octadecylamine is present.

The anodic behaviour of titanium carbide in sulphuric acid solutions

Recent studies on the corrosion and passivation of titanium carbide layers prepared by chemical vapour deposition (CVD), and of titanium carbide single crystals, in aqueous sulphuric acid solutions at 23°C are summarised, together with experiments to test the feasibility of polishing titanium carbide anodically in methanolic solutions. In aqueous 2 N H 2SO 4, corrosion starts at 0.8 V (standard hydrogen electrode) with the formation of TiO 2+, Ti 3+ acting as an intermediate. The onset of passivation is observed at 1.0 V, the surface becoming progressively covered with the hydrated oxide TiO 2.H 2O. At potentials above 1.8 V, dissolution of this oxide is apparent and TiO 2 2+ passes into solution. For the anodic polishing of TiC, the best results were obtained under potentiostatic conditions in a 1 M or 2 M solution of H 2SO 4 in methanol within the range of 1.7 to 4.0 V (saturated mercurous sulphate electrode). Alternatively, a constant current density of 1 A cm -2 may be used. In the polishing region, CO 2, Ti(IV) and Ti(VI) have been identified as products.