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Showing papers on "Sodium sulfide published in 1982"


Journal ArticleDOI
01 Apr 1982
TL;DR: In this paper, a mechanism was proposed in which positive hole-anion pairs were formed at the surface of the colloidal particles before neutralization by electrons takes place, and the mechanism was explained by electron capture.
Abstract: Colloidal cadmium sulfide deposited on 13 nm silicon dioxide particles shows a weak fluorescence with a maximum at 620 – 660 nm (depending on the sample). Oxygen does not quench the fluorescence. All anions exert a quenching effect at concentrations below 10−3 M, S2-, Br−, and I− being the most effective ones. Tl+, Ag+, Pb2+, and Cu2+ strongly quench the fluorescence at concentrations below 10−4 M. Nitrobenzene quenches at higher concentrations in the 10−3 M range. Quenching is attributed to adsorbed ions or molecules. In the case of the anions, a mechanism is proposed in which positive hole-anion pairs are formed at the surface of the colloidal particles before neutralization by electrons takes place. In the case of the cations and of nitrobenzene, quenching is explained by electron capture. Colloidal CdS doped with less than 1% Cu2+ or Ag+ showed a much stronger fluorescence than undoped samples.—Colloidal cadmium sulfide is degraded by light only in the presence of oxygen the quantum yield in aerated solution being 0.04. The action of oxygen is mainly attributed to a reaction with intermediates of the sulfide oxidation by positive holes. In the presence of Tl+ or Pb2+ ions at some 10−5 M, the photo-degradation is drastically promoted up to a quantum yield of 0.24. Cu2+ and Ag+, however, retard the degradation. Both effects are understood in terms of electron scavenging by the adsorbed metal ions and reoxidation of the reduced metal by oxygen or by positive holes. Sodium sulfide protects cadmium sulfide from degradation. In the absence of air, small amounts of hydrogen are formed in Na2S containing solution.

226 citations


Patent
09 Jul 1982
TL;DR: An improved method for removing malodorous sulfur compounds from flue gases generated in kraft or sodium sulfite pulping operations and the like by the absorption process using green liquor, an aqueous solution containing sodium sulfide and sodium carbonate as discussed by the authors.
Abstract: An improved method for removing malodorous sulfur compounds from flue gases generated in kraft or sodium sulfite pulping operations and the like by the absorption process using green liquor, an aqueous solution containing sodium sulfide and sodium carbonate. The malodorous gas compounds, including hydrogen sulfide, methyl mercaptan, and dimethyl sulfide are preferentially absorbed by the sodium sulfide forming sodium hydrosulfide and methanol. Any sulfur dioxide in the gas is absorbed and neutralized by sodium carbonate. In this method carbon dioxide absorption is minimized and the formation of sodium bicarbonate is limited. Sodium bicarbonate formation is minimized in order to avoid its reaction with sodium hydrosulfide which would then release undesirable hydrogen sulfide during absorption, as well as to forestall the need to increase chemical and lime kiln capacity requirements when the green liquor returned to the kraft recovery process contains excess amounts of sodium bicarbonate.

31 citations




Journal ArticleDOI
TL;DR: It appeared that H(2)S was the toxic entity and that HS was less toxic, and the observed stimulation of activity was apparently due to a pH change coupled with the concurrent production of HS from H( 2)S.
Abstract: Nitrogen fixation (C2H2 reduction) in a sediment-water system was studied under anaerobic incubation conditions. Sodium sulfide at low concentrations stimulated activity, with a twofold increase in C2H4 production occurring in the presence of 8 μmol of S2− per ml of stream water. Sodium sulfide at concentrations of 16 μmol of S2− per ml or greater inhibited nitrogen fixation, with 64 μmol of S2− per ml being completely inhibitory. Sulfide at levels of 16 μmol/ml or above inhibited CO2 production, and the degree of inhibition increased with increasing concentration of sulfide. Titanium (III) citrate (used to modify Eh levels) stimulated both nitrogen fixation and CO2 production, but could not duplicate, at any concentration tested, the twofold increase in nitrogen fixation caused by 8 μmol of S2− per ml. Sulfide additions caused pH changes in the sediment, and when the sediment was adjusted and maintained at pH 7.0 all concentrations of sulfide inhibited nitrogen fixation activity. From considerations of the redox equilibria of H2, H2S, and other sulfur species at various pH values, it appeared that H2S was the toxic entity and that HS− was less toxic. The observed stimulation of activity was apparently due to a pH change coupled with the concurrent production of HS− from H2S.

15 citations


Patent
14 Sep 1982
TL;DR: In this article, a polyphenylene sulfide with high bulk density is obtained by polymerization, in the presence of a sulfur source and amide-based solvent, immediately followed by gradually cooling the system to make the polymer separate out in the form of granules of specific size.
Abstract: PURPOSE: To obtain a polyphenylene sulfide with high bulk density, easy to handle, by polymerization, in the presence of a sulfur source and amide-based solvent, of an aromatic polyhalide immediately followed by gradually cooling the system to make the polymer separate out in the form of granules of specific size. CONSTITUTION: An aromatic polyhalide containing pref. ≥70wt% of p-dihalobenzene is subjected to polymerization on stirring in an inert atmosphere pref. at 220W280°C for 1W5hr, in the presence of a sulfur source (e.g., sodium sulfide) and amide-based solvent (e.g., N-methyl pyrrolidone). Following completion of the polymerization, the system is gradually cooled at a rate of 50°C/min (pref. slower than 10°C/min) to 240°C or lower to make the resulting polymer separate out in the form of granules, thus obtaining the objective polyphenylene sulfide with a crystallite size of 60Å or larger. COPYRIGHT: (C)1984,JPO&Japio

13 citations


Journal ArticleDOI
TL;DR: In this paper, a fused ring system made up of 1, 4-thiazine and 3 (2H)-pyridazinone was synthesized, which was obtained from the intramolecular cyclization of 4chloro-5-(2-chloroethylamino)-2-methyl-3(2H)pyridine with sodium sulfide.
Abstract: Two novel fused ring systems made up of 1, 4-thiazine and 3 (2H)-pyridazinone were synthesized. 3, 4-Dihydro-7-methyl-2H-pyridazino [4, 5-b]-1, 4-thiazin-8 (7H)-one was obobtained from the intramolecular cyclization of 4-chloro-5-(2-chloroethylamino)-2-methyl-3 (2H)-pyridazinone with sodium sulfide. An isomer, 3, 4-dihydro-6-methyl-2H-pyridazino-[4, 5-b]-1, 4-thiazin-5 (6H)-one, was directly afforded by the condensation of 4, 5-dichloro-2-methyl-3 (2H)-pyridazinone with sodium 2-aminoethanthiolate.

13 citations


Patent
12 May 1982
TL;DR: In this paper, the authors proposed a method to remove the mercury contained in waste water by using an oxidizing agent to ionize the waste water and then precipitating the mercury with a flocculant.
Abstract: PURPOSE: To efficiently remove mercury contained in waste water, by a method wherein an oxidizing agent is added to a mercury-containing waste water to ionize mercury, thereafter mercury is brought into reaction with a sulfide to form mercury sulfide, and then mercury sulfide is precipitated by adding (a) flocculant CONSTITUTION: Treating steps are constituted by providing a sewage-receiving tank 1, a mixing tank 2 for sodium sulfide, a mixing tank 3 for a flocculant such as ferric chloride, a pH-adjusting tank 4, a mixing tank for a polymer flocculant and a precipirating tank 6 In this case, the treating efficiency can be enhanced by providing an adding tank 2A for an oxidizing agent on the upstream of the tank 2 and ionizing mercury contained in the waste water so that mercury can easily react with sodium sulfide or the like The oxidizing agent may be chlorine, ozone, a hypochlorite, a permanganate a peroxide such as hydrogen peroxide or the like Accordingly, the efficiency in removing mercury contained in waste water in a precipitating treatment can be enhanced COPYRIGHT: (C)1983,JPO&Japio

13 citations


Patent
29 Jul 1982
TL;DR: In this article, a dihalogen-substituted aromatic compound is polymerized in the presence of an anhydrous fine powder of an alkali (earth)metallic sulfide, and a controlled very small amount of solvation water in an organic solvent, preferably N-methylpyrrolidone, under heating at 100W120°C to give the aimed polymer.
Abstract: PURPOSE: To obtain the titled polymer, having a very high molecular weight, and easily oxidizable, by polymerizing a dihalogen-substituted aromatic compound with anhydrous fine powders of the specific compounds as a molecular weight increasing agent and a dehalogenating agent in the presence of a controlled very small amount of water. CONSTITUTION: (C) A dihalogen-substituted aromatic compound, preferably p- dichlorobenzene, is polymerized in the presence of (A) an anhydrous fine powder of an alkali (earth)metallic sulfide, preferably sodium sulfide, (B) an anhydrous fine powder of an alkali (earth)metallic carbonate, preferably sodium carbonate, and a controlled very small amount of solvation water in an organic solvent, preferably N-methylpyrrolidone, under heating at 100W120°C to give the aimed polymer. EFFECT: The polymer is easily processable into molded articles, e.g. tough films without causing pollution problems due to the absence of salts of organic acids. COPYRIGHT: (C)1984,JPO&Japio

11 citations


Patent
01 Sep 1982
TL;DR: In this article, a method for dehydrating pre-polymerization mixtures in the preparation of poly(arylene sulfide) in which a reaction mixture of a sulfur source and an organic amide are contacted at a first pressure within a range of 138 kPa to 414 kPa and an initial temperature in a range from 149 °C to 204 °C.
Abstract: A method for dehydrating pre-polymerization mixtures in the preparation of poly(arylene sulfide) in which a reaction mixture of a sulfur source and an organic amide are contacted at a first pressure within a range of 138 kPa to 414 kPa and an initial temperature in a range of 149 °C to 204 °C to form a complex of the reactants with the mixture subsequently subjected to a decrease in pressure while elevating the temperature to a second temperature at which, at the chosen pressure, essentially all water is removed from the mixture. Other compounds including bases, alkali metal carboxylates, alkali metal carbonates, lithium halides, and lithium borate can be present in the reaction mixture. Preferably the sulfur source is sodium sulfide and the organic amide is N-methylpyrrolidone.

11 citations


Patent
29 Apr 1982
TL;DR: In this article, a method for detoxification of spent catalyst from a fluorination process includes the step of hydrolyzing such spent catalyst in the presence of aqueous calcium chloride to produce insoluble compounds which are separable from the annealing medium.
Abstract: A method for detoxification of spent catalyst from a fluorination process includes the step of hydrolyzing such spent catalyst in the presence of aqueous calcium chloride to produce insoluble compounds which are separable from the aqueous medium. The spent catalyst is one which includes at least one antimony halide, such as SbCl 5 , SbF 5 , SbCl 3 and/or SbF 3 , usually with some halogenated hydrocarbons, such as partially chlorinated methane, partially chlorinated ethane and/or chlorofluorocarbons of 1 to 5 carbon atoms, often in the presence of arsenic compounds, such as AsCl 3 , hydrofluoric acid, and antimony chlorofluoride, such as SbCl 4 F. The spent catalyst may be directly treated with the aqueous calcium chloride solution, very preferably with such solution containing small amounts of a transition metal ion, such as Fe ++ or Fe +++ , or aluminum ion, e.g., Al +++ , after which volatile gases emitted are treated, an organic liquid phase is separated from an aqueous liquid phase containing dispersed precipitated insoluble compounds of antimony and arsenic (when arsenic is present), such as calcium salts of acids thereof, oxides, hydroxides and/or oxyhalides thereof resulting from the hydrolysis reaction, such insolubles are separated from the aqueous liquid medium, as by filtration, and the filtrate is neutralized with lime. The neutralized filtrate, containing calcium chloride resulting from the neutralization reaction, may be returned to the hydrolysis step and/or may be further treated by a sulfide or hydrosulfide and a water soluble iron salt, such as aqueous solutions of sodium sulfide or sodium hydrosulfide, and ferric chloride, to co-precipitate compounds of antimony and arsenic, which may be removed from the aqueous medium, together with precipitated compounds of heavy metals which may be present, after which the filtrate may be discharged to a sewer after suitable monitoring to ensure that the contents of toxic materials are within permissible ranges for such discharge. The antimony compounds removed during the process may be recovered and converted to useful form, as for reuse as fluorination catalysts, and other removed materials may also be recovered, regenerated and/or reused.

Journal ArticleDOI
TL;DR: A β-cyanoalanine (β-(- CNAla)-forming enzyme, which catalyzed the formation of β-CNAla from O-acetyl-L-serine and sodium cyanide, was isolated in crystalline form from Enterobacter sp.
Abstract: A β-cyanoalanine (β-(-CNAla)-forming enzyme, which catalyzed the formation of β-CNAla from O-acetyl-L-serine and sodium cyanide, was isolated in crystalline form from Enterobacter sp. 10-1, a cyanide-resistant strain. The purification procedure involved protamine treatment, ammonium sulfate fractionation, column chromatography on DEAE-cellulose, DEAE-Sephadex A50, Sephadex G-100 and hydroxyapatite, and crystallization with ammonium sulfate. The crystalline enzyme was homogeneous by criteria of the ultracentrifugation and polyacrylamide gel electrophoresis. The enzyme was determined to have a molecular weight of about 68, 000, and consisted of two apparently identical subunits, each having a molecular weight of about 34, 000. The enzyme also catalyzed the formation of cysteine from O-acetyl-L-serine and sodium sulfide, and the cysteine-forming activity was 245 times greater than that of the β-CNAla-forming activity.

Patent
13 Feb 1982
TL;DR: In this article, a 3-18C alkyl mercaptan is reacted with sulfur to give a dialkyl polysulfide, which is then treated with one of sodium sulfide or a phosphine compound, e.g. triphenylphosphine, to afford a dialkyl trisulfide.
Abstract: PURPOSE:To obtain the titled compound, useful as an extreme pressure additive for lubricating oils, and having reduced corrosiveness of copper plates, by treating a dialkyl polysulfide obtained by reacting an alkyl mercaptan with sulfur with a specific sulfur compound. CONSTITUTION:A 3-18C alkyl mercaptan is reacted with sulfur to give a dialkyl polysulfide, which is then treated with one of sodium sulfide or a phosphine compound, e.g. triphenylphosphine, to afford a dialkyl trisulfide. The reaction is carried out by using 0.7-1.5g atoms sulfur based on one mole alkyl mercaptan, sulfur in the presence of an alkaline earth metallic oxide catalyst, e.g. magnesium oxide, and mixing the resultant dialkyl polysulfide with the above-mentioned slufur compound at 30-80 deg.C for 1-5hr. The resultant triphenylphosphine sulfide formed by the reaction of the higher polysulfide with the above-mentioned phosphine compound reduces the corrosiveness of copper plates.

Journal ArticleDOI
TL;DR: In this article, the hygroscopic properties of sodium sulfide have been exploited for thermal storage in the heat-of- adsorption of chemical compounds, and the performance of the model has been reasonably close to the expected level.
Abstract: The storage of solar thermal energy has been a subject of extensive study for many years. Various storage concepts have been extensively investigated. However, little research has been done on energy storage in the heat-of- adsorption of chemical compounds. Zeolite is, perhaps, the only substance that has been studied for its heat-of- adsorption properties (1).A recent proposal utilizes the hygroscopic properties of sodium sulfide for thermal storage (2). Sodium sulfide has a storage capacity of 3600 kJ per kilogram. The system is economically desirable as sodium sulfide costs a mere $0.27 per kilogram (3).Experimental research has been continuing for a year on the feasibility of the system. The performance of the model has been reasonably close to the expected level. It is believed that further work can raise the storage temperatures to levels suitable for space heating and other low temperature ap plications. This system has two problems: 1) the salt has to be under vacuum, 2) the chemical odor in the v...

Journal ArticleDOI
TL;DR: The results of the studies indicated that the β-CNAla-forming enzyme of Enterobacter sp.
Abstract: The properties of a purified β-cyanoalanine (β-CNAla)-forming enzyme isolated from Enterobacter sp. 10–1 were studied.It has been found previously that this enzyme catalyzed the formation of cysteine from O-acetyl-l-serine and soldium sulfide, as well as the formation of β-CNAla from O-acetyl-l-serine and sodium cyanide.The affinity of the enzyme for sodium sulfide in the formation of cysteine was one order of magnitude greater than that for sodium cyanide in the β-CNAla formation. In addition, the optimum pH, pH- and thermal stability of β-CNAla-forming activity were similar to those of cysteine-forming activity. The results of the studies indicated that the β-CNAla-forming enzyme of Enterobacter sp. 10–1 was an O-acetylserine sulfhydrylase catalyzing the formation of cysteine from O-acetyl-l-serine and sulfide. The solution of the enzyme was yellow and exhibited an absorption peak at 420 nm. The enzyme itself contained approximately 1 mol of pyridoxal phosphate per 34,000 g of protein.

Journal ArticleDOI
TL;DR: In this article, a mixture of thiodiglycolaldehyde bis(di- tert -butyl dithioacetal), cis -2,6-bis( tert-butyl-thio)-1,4-dithiane, and trans-2, 6-dialkoxy-1, 4-oxathianes was obtained from 2-methyl-2-propanethiol.

Journal ArticleDOI
TL;DR: In this paper, a field electrode method for the determination of total sulfide in water is described, which involves the use of preweighed sodium sulfide crystals in the standardization process.


Patent
26 Oct 1982
TL;DR: In this paper, a process for reducing carbohydrate losses in the sulphate pulping of wood using sodium hydroxide and sodium sulfide by pretreating the wood in the presence of water with oxygen gas and nitrogen oxide such as NO2 and/or NO and polymeric oxides and double molecules thereof, for from about 3 to about 110 minutes at a temperature within the range from about 25 to about 100°C.
Abstract: PROCESS FOR REDUCING CARBOHYDRATE LOSSES IN THE SULFATE PULPING OF WOOD BY PRETREATING THE WOOD WITH OXYGEN AND NITROGEN OXIDES ABSTRACT OF THE DISCLOSURE A process is provided for reducing carbohydrate losses in the sulphate pulping of wood using sodium hydroxide and sodium sulfide by pretreating the wood in the presence of water with oxygen gas and nitrogen oxide such as NO2 and/or NO and/or polymeric oxides and double molecules thereof, for example, N2O4 or N2O3, for from about 3 to about 110 minutes at a temperature within the range from about 25 to about 100°C, the amount of nitrogen oxide charged, calculated as monomers, being within the range from about 0. 05 to about 1 kilomole per 1000 kg bone-dry wood, resulting in one or several of the following advantages an improved yield of pulp, an improved viscosity, and a reduced requirement for bleaching chemicals in any subsequent bleaching stages.

Patent
01 Sep 1982
TL;DR: In this article, a method for dehydrating pre-polymerizytion mixtures in the preparation of poly(arylene sulfide) in which a reaction mixture of a sulfur source and an organic amide are contacted at an essentially constant pressure within a range of 27 kPa to 276 kPa and a first temperature in a range from 149 °C to 204 °C, to form a complex of the reactants with the mixture subsequently maintained at essentially constantpressure while elevating the temperature to a second temperature at which, at the chosen pressure, essentially all water is removed from
Abstract: A method for dehydrating pre-polymerizytion mixtures in the preparation of poly(arylene sulfide) in which a reaction mixture of a sulfur source and an organic amide are contacted at an essentially constant pressure within a range of 27 kPa to 276 kPa and a first temperature in a range of 149 °C to 204 °C to form a complex of the reactants with the mixture subsequently maintained at essentially constant pressure while elevating the temperature to a second temperature at which, at the chosen pressure, essentially all water is removed from the mixture. Other compounds including bases, alkali metal carboxylates, alkali metal carbonates, lithium halides, and lithium borate can be present in the reaction mixture. Preferably the sulfur source is sodium sulfide and the organic amide is N-methylpyrrolidone.

Patent
01 Oct 1982
TL;DR: In this paper, an aluminum compound, a ferric compound, and a heavy metal-stabilizer are added to waste water containing mercury and fluoride ion, and the pH value of the waste water is adjusted at a nearly neutral pH level, and subjected to solid liquid separation.
Abstract: PURPOSE:To remarkably shorten a treating process and a treating time, by adding an aluminum compound, a ferric compound and a heavy metal-stabilizer to waste water containing mercury and fluoride ion, and then adjusting the pH value of the waste water at a neutral level. CONSTITUTION:An aluminum compound, e.g. aluminum sulfate or poly(aluminum chloride), a ferric compound, e.g. ferric chloride or ferric sulfate, and a heavy metal-stabilizer are added to waste water containing mercury and fluoride ion such as waste water from a garbage-incinerating plant or waste water from the process of making fluorescent lamps or Braun tubes. The waste water is then adjusted at a nearly-neutral pH level, and subjected to solid-liquid separation. As the heavy metal-stabilizer may be used S ion-contg. one such as sodium sulfide or sodium sulfhydride or a selective heavy metal-stabilizer avilable on the market. After addition of the heavy metal-stabilizer, the pH value of the waste water is preferably adjusted to about 6-8.

Patent
03 Mar 1982
TL;DR: In this article, the arsenic content of a phosphoric acid soln was reduced to about 0.01ppm by adding a powdered inorg. arsenic compound such as arsenic acid to the soln.
Abstract: PURPOSE:To attain a low arsenic content below a limit which is conventionally impossible or difficult to attain by previously adding a powdered inorg. arsenic compound to a phosphoric acid soln. to be freed of arsenic with H2S or a soluble sulfide. CONSTITUTION:To a phosphoric acid soln. is added about 2-50wt.ppm solid arsenic or inorg. arsenic compound such as arsenic acid, and they are mixed. H2S or a soluble sulfide such as sodium sulfide is then added and reacted with arsenic in the soln. to produce arsenic sulfide crystals. The crystals are filtered off, and the resulting phosphoric acid soln. is optionally degassed with air or the like to remove dissolved H2S. By this method, the arsenic concn. of the phosphoric acid soln. can be reduced to <= about 0.01ppm.

Journal ArticleDOI
TL;DR: In this paper, a 2-(α-oximinoethyl)-2-methylthiirane was obtained by the reaction of 3,4-dibromo-3-methyl-2-butanone oxime with sodium sulfide.
Abstract: 2-(α-Oximinoethyl)-2-methylthiirane was obtained by the reaction of 3,4-dibromo-3-methyl-2-butanone oxime with sodium sulfide. At the same time, the O-carbamoyl derivative of the α,β-dibromo oxime was converted to the corresponding substituted α,β-unsaturated oxime under the same conditions. Thiirane oxime, like its O-carbamoyl derivative, underwent the desulfuration that is characteristic for thirranes under the influence of tributylphosphine.

Patent
15 Jun 1982
TL;DR: In this article, an aromatic thiosulfinate salt, e.g. p-toluenesulfinate, is added to the reaction mixture to obtain the titled compound of high purity in high yield in reacting an aromatic sulfonyl chloride with a (hydro)sulfide of an alkali metal, NH4, etc.
Abstract: PURPOSE:To obtain the titled compound of high purity in high yield in reacting an aromatic sulfonyl chloride with a (hydro)sulfide of an alkali metal, NH4, etc., by adding an aromatic thiosulfinate salt corresponding to the aromatic sulfonyl chloride to the reaction mixture. CONSTITUTION:An aromatic sulfonyl chloride, e.g. an (alkyl)benzenesulfonyl chloride, is reacted with a (hydro)sulfide of an alkali metal, NH4 or primary or quaternary ammonium, e.g. sodium sulfide, to prepare an aromatic thiosulfonate salt. In the process, an aromatic thiosulfinate salt, e.g. p-toluenesulfinate, is added to the reaction mixture. The amount of the aromatic thiosulfinate salt is preferably 0.01-0.50mol based on 1mol the aromatic sulfonyl chloride. The mixing of the unreacted materials and by-products is very little. USE:An intermediate for a germicide and insecticide.

Journal ArticleDOI
TL;DR: In this paper, a fused ring system made up of 1, 4-thiazine and 3 (2H)-pyridazinone was synthesized, which was obtained from the intramolecular cyclization of 4chloro-5-(2-chloroethylamino)-2-methyl-3(2H)pyridine with sodium sulfide.
Abstract: Two novel fused ring systems made up of 1, 4-thiazine and 3 (2H)-pyridazinone were synthesized. 3, 4-Dihydro-7-methyl-2H-pyridazino [4, 5-b]-1, 4-thiazin-8 (7H)-one was obobtained from the intramolecular cyclization of 4-chloro-5-(2-chloroethylamino)-2-methyl-3 (2H)-pyridazinone with sodium sulfide. An isomer, 3, 4-dihydro-6-methyl-2H-pyridazino-[4, 5-b]-1, 4-thiazin-5 (6H)-one, was directly afforded by the condensation of 4, 5-dichloro-2-methyl-3 (2H)-pyridazinone with sodium 2-aminoethanthiolate.