Showing papers on "Sodium sulfide published in 1995"

Process for the preparation of silane polysulfides

Abstract: Sulfur-containing organosilicon compounds useful as coupling agents in vulcanizable rubbers to enhance various properties, including low rolling resistance for automobile tires, are prepared. Preferred compounds include Ω, 106 '-bis (trialkoxysilylalkyl) polysulfides. In the preferred process scheme, sodium ethoxylate is reacted with hydrogen sulfide gas to yield sodium sulfide. The sodium sulfide is then reacted with sulfur to form the tetrasulfide. The product of that reaction is then reacted with chloropropyltriethoxysilane to form the compound 3,3'- bis (triethoxysilylpropyl) tetrasulfide. The use of hydrogen sulfide gas and sodium metal alcoholates provides an efficient and economical process.

Removal of Cadmium, Lead, Mercury, Tin, Antimony, and Arsenic from Drinking and Seawaters by Colloid Precipitate Flotation

Abstract: The removal of Cd(II), Pb(II), Hg(II), Sn(II), Sn(IV), Sb(III), Sb(V), As(III), and As(V) from aqueous solutions by colloid precipitate flotation using sodium sulfide as the coagulent and oleic acid (HOL) as the surfactant has been investigated. The complete flotation (about 100%) of these elements was attained at pH values of 5.5–6.5, 3–6.5, ≤1, 1–4, 0.5–3, and ≤2, respectively. The effects of some other factors, such as surfactant and coagulent concentrations, sequence of adding reagents, some selected foreign ions, ionic strength, and temperature, on the floatability of these elements have been studied. It was found that both temperature and ionic strength have no appreciable effect on the flotation efficiency of the metal ions investigated. The method was successfully applied to remove completely these metal ions added to 1 L samples of drinking and seawaters at the optimum conditions for each element. Moreover, the mechanism of flotation is proposed.

Continuous in-situ process for upgrading heavy oil using aqueous base

Abstract: The present invention relates to a continuous in-situ process for the removal from heavy oils, of organically bound sulfur in the form of mercaptans, sulfides and thiophenes, heteroatoms selected from the group consisting of nitrogen and oxygen and metals selected from the group consisting of nickel, vanadium and iron, comprising the steps of (a) contacting a heavy oil with aqueous sodium hydroxide at a temperature of about 380° to about 450° C. for a time sufficient to form sodium sulfide; (b) contacting said sodium sulfide of step (a) with water and a transition metal for a time and at a temperature sufficient to form transition metal sulfide, sodium hydroxide, hydrogen and impurities; and (c) recirculating said sodium hydroxide from step (b) to step (a) and removing said transition metal sulfide and said impurities, wherein said impurities are iron, vanadium and nickel. Optionally, molecular hydrogen may be added in the first step. The present invention is useful in removing organically bound sulfur that has been recognized to be difficult to remove, such as thiophenes. Beneficially, the process also removes other heteroatoms (nitrogen and oxygen) and metals (vanadium, iron, nickel) and reduces asphaltene content (n-heptane insolubles), micro concarbon residue, coke, 975° F. fractions, TGA fixed carbon, average molecular weight, density and viscosity.

Ylidylphosphorsulfide, ‐selenide, ‐disulfide, ‐sulfidselenide und ‐diselenide

Abstract: Ylidylphosphorus Sulfides, Selenides, Disulfides, Sulfide Selenides, and Diselenides We report on the first stable monomeric phosphorus mono-chalcogenides 2, 8 and the first stable dichalcogenides 4, 10 without bulky or intramolecularly coordinating substituents. They are stabilized by a high contribution of the zwitterionic resonance formula, which follows both from the NMR spectra and from an X-ray structure determination. Their preparation starts from triphenylphosphoniumylidyl-dichlorophosphanes 1. For the monochalcogenides they are treated with sodium sulfide or selenide or better with bis(trimethylsilyl) sulfide or selenide. In case of the C-phenyl and C-meta-tolyl representatives and also of the C-trimethylsilyl compound a number of secondary, partly novel products are obtained. – The dichalcogenides result from the reaction with sodium disulfide and diselenide, respectively, or from the oxidation of the monochalcogenides. – Alkylation of the monochalcogenides results in ylidylalkylchalcogenophosphenium salts 13, 15. In solution they are in equilibrium with more or less of the covalent form 14, 16, depending on the anion and on the solvent. Alkylation is often accompanied by secondary reactions. A diselenide loses selenium on alkylation.

Synthesis and Structure of a Cyclic Complex of Digold Sulfide Au2S and of Related Compounds

Abstract: 1,4-Bis(diphenylphosphanylmethyl)benzene (1) was converted into its bis[chlorogold(I)] complex [1 · (AuCl)2] upon treatment with two equivalents of chloro(dimethyl sulfide)-gold(I). The reaction of 1 · (AuCl)2 with one equivalent of silver tetrafluoroborate afforded a cyclic di[gold(I)]chloronium tetrafluoroborate [1 · Au2Cl+BF-4]. Substitution of chloride in 1 · (AuCl)2 by sodium methanethiolate in wet chloroform, gave the bis[methylthiogold(I)] complex 1 · (AuSMe)2], while with sodium sulfide a cyclic complex 1 · Au2S was obtained. Reaction of 1 · (AuCl)2 with two equivalents of AgBF4 followed by treatment with diphenyldisulfide or sodium methanethiolate yielded the cyclic methyl/phenylsulfonium tetrafluoroborates 1 · Au2SPh+ BF-4 and 1 · Au2SMe+BF-4, respectively. All compounds were identified on the basis of their analytical and spectroscopic data. The crystal structures of 1 · (AuCl)2, 1 · (AuSMe)2, and 1 · Au2S have been determined. The Au2S complex has a cyclic structure with a narrow Au-S-Au angle of 86.7(1)° indicating a significant intraannular Au…Au interaction.

Treatment of flue gas desulfurization waste water

Abstract: PROBLEM TO BE SOLVED: To treat flue gas desulfurization waste water with a biological treatment to remove not only ammonia nitrogen but also dithionic acid in the waste water by mixing the waste water contg. dithionic acid with a reducing agent to subject the waste water to reduction treatment and thereafter, performing an activated sludge treatment of the reduced waste water. SOLUTION: In this treatment, the desulfurization waste water 1 contg. ammonia nitrogen and dithionic acid is allowed to flow into a flocculating sedimentation stage 2 to remove SS(suspended solid) from the waste water 1. At this time, peroxodisulfuric acid in the waste water 1 is not removed and allowed to flow into a reduction stage 4 placed next to the stage 2. In the reduction stage 4, a reducing agent 5 and an acid 6 are added to the resulting waste water to subject it to reduction treatment. Thus, peroxodisulfuric acid in the waste water is decomposed and an equivalent amount of the reducing agent 5 to the amount of peroxodisulfuric acid is converted into sulfates, sulfur compounds or elemental sulfur. The reduced waste water 7 is allowed to flow into a nitrification stage 8 placed subsequently to the reduction stage 4. As the reducing agent, a thiosulfate such as sodium thiosulfate or sulfide such as sodium sulfide or iron sulfide is used.

Polyarylene sulfide and its production

Abstract: PURPOSE: To obtan a polyarylene sulfide extremely reduced in the generation of burrs on its injection molding, high in the shear rate dependency of the melt viscosity and excellent in moldability by specifying the melt viscosity and the shear rate. CONSTITUTION: The polyarylene sulfide has a melt viscosity V6 of 300-4000 poises and a relation of the inequality between the melt viscosity V6 and the shear rate N. The method for producing the polyarylene sulfide comprises feeding (A) an alkali metal sulfide, (B) a dihalogenoaromtic compound and (C) an aromatic compound having three or more functional groups into a reaction system in a component A/B molar ratio of 0.97-1.02 and in a component C/A molar ratio of 0.002-0.015, reacting the fed compounds in a polar solvent, adding (D) a mol.wt.-controlling agent to the reaction system in an amount of 0.001-0.02 mole per mole of the fed component A, and further continuing the reaction. The component A, the component B, the component C and the component D are preferably sodium sulfide, p-dichlorobenzene, dichloroaniline, etc., and thiophenol, etc., respectively.

Production of high molecular weight polyarylene sulfide

Abstract: PURPOSE:To obtain the subject polymer excellent in molding properties at a low cost without using an expensive assistant by reacting an aromatic dihalogen compound with an alkali metal sulfide in an organic amide solvent in the presence of an aromatic polyhalogen compound under condensation- refluxing of a gaseous phase without using an expensive assistant. CONSTITUTION:This polyarylene sulfide having a high molecular weight and excellent for melt spinnability, blow moldability and extrusion moldability is obtained at a low cost by the use of low pressure reaction vessel without using an expensive assistant requiring high cost for separating and recovering from a product by reacting an alkali metal sulfide (e.g. sodium sulfide) with an aromatic dihalogen compound (e.g. p-dichlorobenzene) in an aromatic amide solvent (e.g. N-methyl-2-pyrrolidone) in the presence of an aromatic polyhalogen compound (e.g. 1,3,5-trichlorobenzene) in an amount of 0.005-1.5mol% based on the alkali metal sulfide under pressure at 260 deg.C and allowing to reflux a portion of gaseous phase in a reaction vessel as the liq. phase by cooling a vapor-holding part of the reaction vessel to condense the portion of the gaseous phase.

Kinetic-spectrophotometric determination of trace amounts of selenium with catalytic reduction of gallocyanine by sulfide

Abstract: A kinetic-spectrophotometric method is presented for the determination of trace amounts of selenium (0.010 – 0.500 μ.ml−1), based on the catalytic effect of Se(IV) on the reduction of Gallocyanine by sodium sulfide, which yields a colorless product. The reaction is followed spectrophotometrically by measuring the absorbance change at 620 nm and 30 °C. The detection limit is 0.002 μ.ml−1. Se(VI) can be reduced with hot hydrochloric acid to Se(IV), allowing determination of total selenium. The variables which affected the reaction rate were fully investigated and the optimum conditions were established. The relative standard deviation for 50 ng.ml−1 of selenium was 2.5% (n=6). The method was applied to determination of Se(IV) in real samples.

The depletion of nitric oxide by reaction with molten sodium carbonate and sodium carbonate/sodium sulfide mixtures

Abstract: This study was an investigation of the depletion of NO by reaction with sodium species that are present in a kraft recovery furnace. Thermodynamic calculations identified many reactions that could occur to form sodium nitrate (NaNO3) as a product. Because NaNO3 begins to thermally decompose at temperatures greater than 450°C, it is believed that NaNO3 may not be a final product, but could play a role as an intermediate species in the depletion of NO. The rate of depletion of NO by reaction with molten sodium carbonate and mixtures of sodium carbonate and sodium sulfide has been determined over the temperature range, T = 860 to 973°C. The heterogeneous reaction system has been shown to fit a mixed control reaction model where both mass transfer and chemical reaction kinetics play an important role. The rate of depletion of NO has been shown to follow a pseudo first-order rate expression. Values for the rate constant have been determined experimentally for the depletion of NO by reaction with Na2CO3 and mixtures of Na2CO 3/Na2S. Analysis of gaseous products indicated that all of the NO that is depleted by reaction with Na 2CO 3 is converted to oxygen (02) and nitrogen (N2). For Na2CO 3/Na2S mixtures, no oxygen could be detected in the gas stream. It was shown that the oxygen formed by depletion of NO was consumed by the sodium sulfide to form sodium sulfate (Na 2SO 4). Analysis of the nitrogen content of samples taken from industrial furnaces showed that approximately half of the nitrogen entering the furnace in black liquor could not be accounted for. It was therefore assumed that nitrogen leaves the furnace as a gas phase species, e.g., N 2 or

Development of simple permeation device for the generation of hydrogen sulfide

Abstract: A simple permeation device for the generation of low concentrations (ppb) of hydrogen sulfide is described. It is based on the generation of hydrogen sulfide from two solution sources, namely, sodium sulfide and thioacetamide, and its permeation through silicone rubber and Teflon membrane, respectively. The permeated hydrogen sulfide along with the carrier gas (air) was trapped in 10 ml of 0.1 mol l–1 NaOH–0.1% EDTA and analysed by a standard Methylene Blue method. The relative standard deviation for 10 determinations was found to be 4.9% at the 201 ppb level for one of the developed permeation devices.

Reactions of dichloromethane with thioanions. 2. formation of 5-alkyl-1,3,5-dithiazinanes, 3,5-dialkyl-1,3,5-thiadiazinanes, and 1,3,5-trialkyl-1,3,5-triazinanes by reaction of dichloromethane with sodium sulfide and monoalkylamines

Abstract: The reaction of dichloromethane with sodium sulfide and monoalkylamines, catalyzed by polyethyleneglycol 1,500, is studied. A mixture of 5-alkyl-1,3,5-dithiazinane, 3,5-dialkyl-1,3,5-thiadiazinane, and 1,3,5-trialkyl-1,3,5-triazinane is obtained. The proportion of these heterocycles depends on the amine structure and the presence of sodium hydroxide.

Production of mercaptopropylalkoxysilane

Abstract: PURPOSE: To obtain a mercaptopropylalkoxysilane in a high yield under a mild condition, capable of suppressing the production of the by-product of a sulfide compound, and at the same time obtaining a by-product salt easily dealt with the waste treatment. CONSTITUTION: This mercaptopropylalkoxysilane is obtained by reacting 3- halopropylalkoxysilane expressed by the formula, X-(CH 2 ) 3 -Si(OR) a R 3-a (X is Cl or Br, R is methyl, ethyl or propyl group and may be either the same or different, (a) is an integer of 1, 2, 3) after reacting anhydrous sodium sulfide with hydrogen sulfide, or reacting a hydrogen sulfidized alkali metal with the 3-halopropylalkoxysilane expressed by the above formula in a hermetically sealed condition under a pressure in the presence of an excess hydrogen sulfide. COPYRIGHT: (C)1996,JPO

Production of polysulfide digestion solution

Abstract: PURPOSE: To efficiently prepare polysulfide digestion solution by oxidative treatment of a chemical solution containing sodium sulfide in the presence of lime mud, a transition metal compound and a quinone compound. CONSTITUTION: The green liquor obtained in the chemical recovery process for the kraft pulp is combined with one or more kinds of foam regulator selected from an anionic or cationic surfactant and black liquor and the resulting sodium sulfide-containing chemical solution is oxidatively treated by feeding an oxygen-containing gas such as heated and moistened air into the solution in the presence of lime mud, 0.01-10wt.% of a manganese oxide and/or its salt on the absolutely dry basis of the lime mud and 0.1-20wt.% of a quinone such as dihydroxyanthracene to give this polysulfide digestion solution efficiently. COPYRIGHT: (C)1996,JPO

Kinetics of the interaction between 2-nitroethenylbenzene and some s-containing nucleophiles

Abstract: The kinetics of the reaction of 2-nitroethenylbenzene with sulfur-containing nucleophilic reagents such as sodium phenylsulfinate, sodium thiosulfate, sodium bisulfite, sodium sulfide, sodium thiophenolate, and sodium thioglycolate was studied by means of UV spectroscopy. The change in the nucleophilic reactivity of these nucleophiles depending on their basicity was studied. The reactions can be expressed by a second-order kinetic equation. Rate constants, activating energy and enthalpy of activation were calculated at 288–308 K.

Method for uptaking valuable metal in plating liquid

Abstract: PURPOSE:To precipitate and recover valuable metals by treating a plating liquid containing valuable metal ions, complexing agent, and the like at high temp. under high pressure in the presence of a metal scavenger comprising sulfides. CONSTITUTION:A waste plating liquid containing valuable metal ions (gold, silver, copper, nickel, etc.,) and a complexing or chelating agent is treated at high temp. at about 130-250 deg.C under high pressure as about 2.7X10 to 40X10 Pa in the presence of a metal scavenger comprising sulfide (e.g. sodium sulfide) to precipitate valuable metals. The ratio of the amt. (S) of sulfides added to the metal (Me) in the waste liquid (equiv. ratio of S/Me) is about =7. Thereby, not only noble metals such as gold and silver but valuable metals such as copper and nickel can be recovered and reused.

High molecular-weight polyarylene sulfide for turbular extrusion molding

Abstract: PURPOSE:To obtain the subject polyarylene sulfide useful for a piping, etc., having excellent impact resistance, etc., by adding a specific amount of a polyhalo aromatic compound to an organic amide-based solvent and reacting the polyhalo aromatic compound with an alkali metal sulfide and a dihalo aromatic compound. CONSTITUTION:(A) An alkali metal sulfide (specific sodium sulfide) is reacted with (B) a dihalo aromatic compound (preferably p-dichlorobenzene) and (C) 0.2-1.0mol%, preferably 0.3-0.6mol% (based on the fed alkali metal sulfide) of a polyhalo aromatic compound (preferably 1,2,4-trichlorobenzene or 1,3 5- trichlorobenzene) in an organic amide solvent. A vapor phase part in a reactor is cooled during the reaction, and a part of the vapor phase is condensed in the reactor and is refluxed to a liquid phase to give the objective polyarylene sulfide (PAS). The PAS has preferably 20,000-50,00 poise melt viscosity and -20 to +20% thickening ratio during melting.

Printed circuit board and manufacture thereof

Abstract: PURPOSE:To impart conductivity to an inner surface of a hole for a viahole of a printed circuit board at low cost and to reduce the number umber of processing steps and a processing time for imparting the conductivity. CONSTITUTION:A printed circuit board has a laminate of an insulating layer 1 and conductive layers 2 formed on both side surfaces of the layer 1 and formed with a viahole Vh having a hole for the viahole and a viahole plating layer 3 formed on its inner surface, and comprises a thin layer 4 of copper sulfide, nickel sulfide between the layer 3 and the layer 1 to become its base. The layer 4 is formed by reacting copper salt or nickel salt aqueous solution with sodium sulfide aqueous solution in the hole for the viahole thereby to adhere the copper sulfide or nickel sulfide to an inner surface of the hole.

Production of 1,4-dihydropyridinemonocarboxylic acid

Abstract: PURPOSE:To efficiently obtain the compound e.g. for a cardio-vascular agent by removing a protecting group of 3-cyanoethyl-1,4-dihydropyridine diester in the presence of sodium sulfide or tetrabutylammonium fluoride in an organic solvent. CONSTITUTION:The compound expressed by formula II is selectively obtained by removing the protection group of 3-cyanoethyl-1,4-dihydropyridine diester expressed by formula I [X is H, alkyl, alkoxy, halogen, trifluoromethyl, nitro or cyano; R and R are H, alkyl, cyano, alkylamino, aminoethoxymetyl or aminocarbonyloxymethyl; R is (substituted) alkyl, aralkyl, monoalkylamino, dialkylamino, thioalkyl, thiophenyl, 1-benzyl-3-piperidinyl, 3-phenyl-2-propene, nitrooxyalkyl or nicotinoylaminoalkyl] in the presence of sodium sulfide or tetrabutylammonium fluoride in an organic solvent.

Production of 5,5'-bi-1h-tetrazoles

Abstract: PURPOSE:To produce salts of industrially advantageous 5,5'-bi-1H-tetrazole (BHT) in high quality and yield by improving the filterability of salts formed as a by-product in producing sodium or manganese salt of the BHT. CONSTITUTION:This method for producing manganese salt of BHT is to react sodium azide, sodium cyanide and manganese dioxide with acetic acid in water solvent at a low temperature by dropping the acetic acid thereinto and then carry out the reaction at a high temperature for a prescribed time in two-stage reaction at the low and high temperatures and further treat the unreacted hydrogen azide with sodium nitrite in the system. Furthermore, this method for producing sodium salt of the BHT is to add sodium sulfide or sodium hydrosulfide to the manganese salt of the BHT in the presence of the water solvent and separate the manganese as a sulfide by filtration. Thereby, the salts of the BHT useful as an inflator for air bags with hardly any toxicity or a foaming agent for thermoplastic resins can industrially and safely be produced in high purity and yield.

Composition for treating cementitious waste

Abstract: PURPOSE:To safely and simply reutilize waste by converting a heavy metal contained in a compsn. to hardly soluble sulfide. CONSTITUTION:A compsn. B composed of sodium hydrosulfide or sodium sulfide is added to and mixed with 97-99 pts.wt. of a compsn. A selected from a standard compsn., a high concn. gypsum compsn. and an intermediate compsn. of them all of which are respectively different in water content or waste is made harmless by the compsn. B or a part of the compsn. B (e.g. sodium hydrosulfide) and subsequently subjected to harmlessness finish and solidification treatment. Concretely, a waste storage tank (1) and sodium hydrosulfide (2) are added to perform kneading for a definite time by a kneader to convert a harmful heavy metal in waste to sulfide by sodium hydrosulfide (2) being a sulfiding agent. Continuously, a main compsn. (3) and water are added as secondary treatment to again perform sufficient kneading. In this case, in order to obtain uniaxial compression strength in an objective product, it is necessary to predetermine the addition amt. of the main compsn. (3).

Improvement of Specificity for Sulfite in Thiobacillus thiooxidans JCM7814 by Heat Treatment

Abstract: Heat treatment was done to improve the substrate specificity for sulfite in Thiobacillus thiooxidans JCM7814 cells. Cell suspension in 0.1 M sodium citrate–NaOH buffer (pH 5.5) was heated at 60°C for 30 min. Sodium sulfite, sodium sulfide, and sodium dithionite at the concentration of 0.01 M protected the cells from thermal inactivation of sulfite oxidation. Sodium sulfite was the most effective among the three additives. Intact cells can oxidize various inorganic sulfur compounds, but the heat-treated cells oxidized only sulfite.

Artificial patina copper sheet

Abstract: PURPOSE:To improve the adhesion of a patina film and to improve the weather resistance of a sheet by forming a copper sulfide layer with a certain thickness on the substrate of a copper or copper alloy sheet and thereafter forming a patina film on the copper sulfide layer by an anodic electrolysis method CONSTITUTION:A copper sulfide layer with 0005 to 20mum thickness is formed by the well-known method in which the surface of a copper or copper alloy substrate is treated by an aq soln of potassium sulfide, sodium sulfide, ammonium polysulfide, sodium polysulfide or the like Next, a patina film is formed, and, in this method, the conventional method may be applied Namely, the surface of the copper sheet is subjected to degreasing treatment and pickling treatment and is thereafter immersed in an electrolyte contg carbonate, bicarbonate, ammonium salt, oxyacid salt or the like, and electrolysis is executed with the copper sheet to be treated as the anode Since the patina film is formed on the copper sulfide layer by an anodic electrolysis method, voids are hardly generated between the substrate and the patina film, and the film with tight adhesion can be formed

Method for removing dimethyl sulfoxide in exhaust gas

Abstract: PURPOSE:To decompose and remove dimethyl sulfoxide in exhaust gas accompanied by IC treatment by washing and decomposing dimethyl sulfoxide in the exhaust gas with an excess sodium hypochlorite aqueous solution and reducing the excess sodium hypochlorite with a sodium sulfide aqueous solution. CONSTITUTION:Exhaust gas containing dimethyl sulfoxide (DMSO) is sent from an inlet 1 into a tower by a fan F. The aqueous solution of sodium hypochlorite (NaCIO) stored in the bottom of the tower is sprinkled 3 to packing material 2 by a pump P. Thereby DMSO is decomposed and removed nearly completely and exhaust gas containing DMSO of extremely fine amount, i.e., <=1ppm is discharged from an outlet 4. Excess (NaCIO) is reduced and treated by a sodium sulfide solution. The used Na2S solution is regulated to pH 10-13 and -500 to -1500mV oxidation-reduction voltage. Reaction is performed as shown in the following expression. 4 NaCIO+Na2S Na2SO4+4 NaCI.

Production of p-aminothiophenol

Abstract: PURPOSE:To provide a method for industrially and advantageously producing p-aminothiophenol in high purity and yield by using a surfactant. CONSTITUTION:This method for producing p-aminothiophenol is to react p- chloronitrobenzene with sodium sulfide in an aqueous solution containing a surfactant and neutralize the resultant reactional solution with an acid. In this case, the time of dropping an aqueous solution of sodium sulfide into a reactional vessel is >=4hr and an organic carboxylic acid is used for the neutralization. The pH of the reactional solution is regulated to 5.5-6.5.