46 results about "Tungstate ion" patented technology

The invention relates to a preparation method of a bismuth tungstate quantum dot and a preparation method of a bismuth tungstate quantum dot-graphene composite material. The preparation method of the bismuth tungstate quantum dot comprises the steps: a, dissolving a soluble bismuth salt and sodium oleate in water, stirring for more than 1 hour to form a first emulsion-like precursor solution containing bismuth ions, wherein the molar concentration of the sodium oleate in the first precursor solution is smaller than 0.3mol/L; b, dissolving the soluble bismuth salt in water, and stirring and ultrasonically dispersing to form a uniform second precursor solution containing tungstate ions; and c, mixing the first precursor solution and the second precursor solution, and carrying out hydro-thermal synthesis for more than 12 hours at 120-180 DEG C. According to the bismuth tungstate quantum dot and the bismuth tungstate quantum dot-graphene composite material, prepared by using the methods provided by the invention, the bismuth tungstate quantum dot is about 3nm in dimension,not only has extremely high photocatalytic activity, but also has extremely high stability. The preparation methods disclosed by the invention do not special equipment and rigor conditions, are simple in process, strong in controllability and easy for realization of scale production and have practicability.

A method for completely cleaning high concentration molybdate solution by removing trace tungsten comprises the steps of pre-adjusting pH value of molybdate solution containing trace tungsten, allowing tungstate ions to completely polymerize to form polytungstate ions, and performing selective adsorption of tungsten with adsorption bed filled with macroporous weak base anion exchange resin, so as to completely remove tungsten from molybdate solution.

The invention discloses a method used for purifying a sodium tungstate solution. The method comprises following steps: at 50 to 100 DEG C, pH value of the sodium tungstate solution is adjusted so as to realize silicon precipitation and obtain a first sodium tungstate mixed solution containing silicon precipitates; a magnesium salt is added into the first sodium tungstate mixed solution so as to obtain a second sodium tungstate mixed solution; at a temperature of 50 DEG C or higher, stirring is carried out continuously so as to obtain a third sodium tungstate mixed solution containing precipitates; and the third sodium tungstate mixed solution is subjected to filtration so as to obtain a filtrate, wherein the filtrate is the purified sodium tungstate solution. According to the method, solid salts are adopted for purification and processing, so that comprehensive removing of fluorine, phosphorus, arsenic, and silicon can be realized, and influences on tungstate ion exchange and product purity caused by introducing of impurity negative ions and positive ions are avoided. After treatment, content of impurities, such as fluorine, phosphorus, arsenic, and silicon, in the sodium tungstate solution is reduced greatly.

Chromium-free conversion coating treatment solutions and processes for depositing a colored layer on zinc or galvanized steel, aluminum, magnesium or their alloys, are provided comprising: hexafluorotitanate and/or hexafluorozirconate ions; molybdate and/or tungstate ions; one or more chelating complex formers; and a copolymer of alkylene phosphonic or alkylene phosphinic acid and one or more unsaturated carboxylic acids.

The invention discloses manufacturing methods of an electrolytic copper foil having football-shaped copper particles and a circuit board assembly. The manufacturing methods of an electrolytic copper foil having football-shaped particles include forming a copper foil by an electrolyzing process, wherein the foil layer has a predetermined surface. Then, a roughening treatment layer is formed on thepredetermined surface of the copper foil to form an electrolytic copper foil having football-shaped protrusions on a surface layer. The roughening treatment layer includes a plurality of football-shaped copper particles, and a funnel-shaped arrangement space exists between two adjacent football-shaped copper particles. The steps of forming the roughening treatment layer further includes performinga first electrolytic roughening treatment and a first electrolytic curing treatment, in which a first electrolyte solution used in the first electrolytic roughening treatment includes copper ions, sulfuric acid, arsenic trioxide, and tungstate ions, in which the copper concentration ranges from 3 to 40 g/L, the sulfuric acid concentration ranges from 100 to 120 g/L, the arsenic trioxide concentration is not more than 20 ppm, and the tungstate ion concentration ranges from 5 to 20 ppm. Thus, since the surface layer has the electrolyte copper foil having the football-shaped structure and has alarger contact area with a resin substrate, higher peeling strength can be achieved.

The invention relates to a preparation method of nanometer tungsten powder, which is mainly used for preparing the nanometer tungsten powder by organizing tungsten. The method comprises the following steps: organizing sodium tungstate into tungsten salicylate, wherein the molar ratio of the sodium tungstate to sulfuric acid to salicylic acid is 1:(0.8-1.2):(0.8-1.2), and the molar concentration of tungstate ions in the prepared aqueous solution is 1 to 2 mol/L; performing thermal decomposition on the tungsten salicylate to obtain nanometer tungsten oxide, wherein the temperature is 200 to 340 DEG C and is preserved for 0.5 to 8 hours; and performing hydrogen reduction on the nanometer tungsten oxide to obtain the nanometer tungsten powder. The tungsten salicylate with low boiling point is formed by organizing the tungsten and then is subjected to thermal decomposition at 200 to 300 DEG C to form the nanometer tungsten oxide, the nanometer tungsten oxide is subjected to hydrogen reduction to obtain the nanometer tungsten powder with uniform granularity, the granularity of the nanometer tungsten powder is 20 to 40 nm, the purity of the nanometer tungsten powder is 99.99 percent, and the yield of the nanometer tungsten powder exceeds 99 percent. The method has the prominent advantages of simplicity in operation, cleanness and environmental friendliness.

The invention discloses a method for extracting tungsten from alkaline crude sodium tungstate solution without a renewable recyclable extracting system. The method is characterized in that the hydrocarbonate containing methyl trialkyl ammonium and an organic phase of the hydrocarbonate composite extracting agent are used for carrying out multilevel countercurrent extraction of alkaline crude sodium tungstate solution, the obtained load organic phase is processed in multilevel countercurrent back extraction by utilizing a mixed aqueous solution of ammonium bicarbonate and ammonium carbonate after being washed by water to obtain ammonium tungstate solution, and the organic phase after the back extraction is directly returned to the extraction process to be recycled. By adopting the method, the tungstate ions in the alkaline crude sodium tungstate solution are selectively extracted to prepare the ammonium tungstate, so that the tungstate ions can be effectively separated from the impurity ions such as phosphorus, arsenic, silicon and the like, the extracting agent can be directly reused without being regenerated, the process flow is shortened, the consumption of chemical reagent is reduced, the emission of waste water is reduced, and the industrialized production can be favored.

The invention relates to a high-efficiency corrosion inhibitor for sea water desalinization first-level reverse osmosis producing water. One liter of high-efficiency corrosion inhibitor comprises 3 to 20 milligrams of sodium silicate (based on silicon dioxide (SiO2)), 30 to 50 milligrams of sodium hexametaphosphate, 2 to 4 milligrams of zinc sulfate (based on zinc ions (Zn<2+>)), 4 to 10 milligrams of sodium tungstate (based on tungstate ions (WO4<2->) and 2 to 5 milligrams of benzotriazole or methyl benzotriazole. By the high-efficiency corrosion inhibitor, the corrosion rates of the metal materials commonly used in a heat-engine plant, such as carbon steel, red copper and the like in the sea water desalinization first-level reverse osmosis producing water are reduced from 1.14007 mm/a to 0.04282 mm/a and from 0.06173 mm/a to 0.00606 mm/a respectively; the corrosion inhibition rates of the high-efficiency corrosion inhibitor on the carbon steel and the red copper are over 96.24 percent and 90.18 percent respectively; the corrosive action of the first-level reverse osmosis producing water on the materials is greatly relieved; and the tendency of the metal surface pitting is reduced, so that the service life of each of pipelines and equipment is greatly prolonged.

The invention discloses a preparation method of molybdenum-tungsten alloy powder. The method comprises the steps that firstly, molybdenum trioxide and tungstic acid are added into diluted ammonia water to be dissolved to obtain an ammonium molybdate and ammonium tungstate mixed solution; secondly, the ammonium molybdate and ammonium tungstate mixed solution is sprayed and dried to obtain a molybdenum-tungsten composite oxide precursor; thirdly, the molybdenum-tungsten composite oxide precursor is subjected to roasting decomposition under the temperature gradient condition to obtain a molybdenum-tungsten composite oxide; fourthly, the molybdenum-tungsten composite oxide is subjected to first-stage reduction under the hydrogen condition to obtain a molybdenum-tungsten low-valence oxide; andfifthly, the molybdenum-tungsten low-valence oxide is subjected to second-stage reduction under the hydrogen condition to obtain the molybdenum-tungsten alloy powder. The molybdenum-tungsten alloy powder is prepared by fully mixing molybdate ions and tungstate ions and conducting roasting and reduction, so that size and mass differences of molybdenum particles and tungsten particles are small, hybrid power is high, the uniformity of the molybdenum-tungsten alloy powder is improved, and the problem of insufficient uniformity caused by mechanical mixing of molybdenum powder and tungsten powder is eliminated.

An aqueous conversion coating composition for treating metal substrates such as aluminum, aluminum alloys, zinc, zinc alloys, magnesium, magnesium alloys and steel to provide a conversion coating thereon. The conversion coating composition comprises a) a source of aluminum ions; b) a fluoro compound; c) at least one pH adjuster; d) a source of Group VIB metal ions selected from the group consisting of tungstate ions and trivalent chromium ions; and e) optionally, a preservative. The conversion coating composition provides a corrosion resistant coating on the metal surface and improves the adhesion of subsequently applied layers.

The catalyst comprises a platinum group metal supported on a carrier consisting of a mixture of aluminium oxide, zirconium oxide, and a sulphate ion or tungstate ion. Aluminium hydroxide, the aluminium oxide precursor, is pre-treated using only organic or inorganic acids with an acid module of 0.01-0.3, or in combination with at least one metal compound selected from the group consisting of: yttrium, magnesium, zinc, calcium, barium, cadmium, and strontium, to yield the catalyst wherein the percentage (by volume) of pores with a diameter of 5-8 nm constitutes more than 60% of the total pore volume. The technical result of the invention is the increased activity, selectivity and durability of the produced catalyst for isomerisation of hydrocarbons.

The invention discloses a preparation method of sulfo-molybdate for separating molybdenum from tungstate solution. Phosphorus pentasulfide serves as vulcanizing agent; after the vulcanizing agent is added into molybdenum-contained tungstate solution, the vulcanizing agent is hydrolyzed to release sulphur ions; the sulphur ions and molybdate are subject to vulcanization reaction to generate sulfo-molybdate; and tungsten still exists in the form of tungstate ion. The vulcanizing agent used by the method has the advantages of high sulphur content and low price, and the preparation cost of the sulfo-molybdate can be obviously lowered.

The invention relates to a preparation method of tungsten alloy precursor composite powder, a ceramic aluminum oxide enhanced tungsten alloy and a preparation method of the ceramic aluminum oxide enhanced tungsten alloy, and belongs to the technical field of tungsten alloy. The preparation method of the tungsten alloy precursor composite powder comprises the steps that ammonium metatungstate and amixed solution of soluble aluminum salt are provided, oxalic acid is added into the mixed solution till pH is not larger than 1.5, a complex reaction is carried out, a solvent is removed, and mixed powder is obtained. According to the preparation method, the pH is adjusted through oxalic acid after liquid-liquid mixing, hydrogen ions and tungstate ions in the solution will react to generate tungstate precipitate; oxalate ions and aluminum ions react to generate aluminum oxalate precipitate, serious segregation caused by the mass difference of tungsten atomic nucleuses and aluminum atomic nucleuses can be avoided, the uniformity degree of tungstic acid and aluminum oxalate in the obtained powder is improved, molecular mixing is achieved, and a raw material base is provided for improving high-temperature wear-resisting erosion-resistance performance of tungsten alloy.

The invention discloses micro/nano potassium yttrium tungstate near-spherical particles and a preparation method thereof. The preparation method comprises the following steps: regulating the pH value of a soluble tungstate solution to 7-8.5 and the pH value of Y<3+> of the yttrium ion solution to 5-6.5, mixing according to the tungstate ion:yttrium ion mol ratio of 2:1, regulating the pH value of the mixed solution to 5-7.5, uniformly stirring, adding acetylacetone accounting for 10-20 vol% of the mixed solution, and carrying out ultrasonic vibration to obtain a precursor solution; holding the precursor solution by hydrothermal sealing to obtain a white precipitate, wherein the hydrothermal temperature is 140-180 DEG C, and the holding time is 20-24 hours; and centrifuging the white precipitate, and carrying out heat treatment to obtain the micro/nano potassium yttrium tungstate near-spherical particles. The micro/nano potassium yttrium tungstate near-spherical particles are composed of KY(WO4)2 particles, the particle size is 0.100-1 mu m, and the particle shape is near-spherical. The invention enhances the luminescence efficiency of the powder, can be used as a luminescent material, and can be widely used in the fields of road signs, various energy-saving illuminators, biomedical labels, aviation display devices, various meters and computers, and the like.

The invention relates to a method for recovering tungstate radicals in beneficiation wastewater, and concretely discloses a method for recovering and adsorbing tungstate radicals in scheelite beneficiation wastewater. The invention aims to solve the technical problems of low recovery rate and low recovery rate of tungstate radicals in scheelite beneficiation wastewater in the prior art. The methodcomprises the following steps: a three-electrode system which is composed of a polyaniline/carbon cloth composite electrode material, an Ag/AgCl electrode and a platinum electrode is connected to anelectrochemical workstation, and electro-adsorption is carried out under the condition of electric field force by using the polyaniline/carbon cloth composite electrode material as a working electrode, the Ag/AgCl electrode as a reference electrode, the platinum electrode as a counter electrode and the scheelite beneficiation wastewater to be treated as an electrolyte. The method has a simple andrapid process, and makes the recovery rate of tungstate ions adsorbed for 2 h reach 75%.

The invention provides a synthesis method of an electrode material cobalt tungstate for a supercapacitor. The synthesis method comprises: carrying out mixing dissolving on a cobalt salt and deionizedwater to obtain a solution A, carrying out mixing dissolving on a morphology regulator, a tungstate and deionized water to obtain a solution B, mixing the solution A and the solution B according to avolume ratio of 1:1, carrying out a precipitation reaction, cooling after the precipitation reaction is finished, washing, and drying to obtain cobalt tungstate. According to the invention, based on the high conductivity of the tungstate, the cobalt tungstate prepared by combining cobalt ions and tungstate ions is used as a capacitor electrode material, so that the high reversibility, the excellent cycle performance and the excellent stability can be achieved, and the prepared cobalt tungstate has a coralline-like structure, has a specific surface area, can substantially improve the specific capacitance value of the electrode material, and further has good electrochemical performance.

The invention discloses manufacturing methods of an electrolytic copper foil and circuit board assembly. The manufacturing methods of an electrolytic copper foil having needle-shaped particles includeforming a copper foil by an electrolyzing process, wherein the foil layer has a predetermined surface. Then, a surface treatment layer is formed on the predetermined surface of the copper foil to form an electrolytic copper foil having a needle-shaped structure on a surface layer. The surface treatment layer includes a plurality of needle-shaped copper particles, and a needle-shaped arrangement space exists between two adjacent needle-shaped copper particles. The steps of forming the surface treatment layer further includes performing a first electrolytic roughening treatment and a first electrolytic curing treatment, in which a first electrolyte solution used in the first electrolytic roughening treatment includes copper ions, sulfuric acid, arsenic trioxide, and tungstate ions, in whichthe copper concentration ranges from 3 to 40 g/L, the sulfuric acid concentration ranges from 100 to 120 g/L, the arsenic trioxide concentration is not more than 20 ppm, and the tungstate ion concentration ranges from 5 to 20 ppm. Thus, since the surface layer has the electrolyte copper foil having the needle-shaped structure and has a larger contact area with a resin substrate, higher peeling strength can be achieved.

The invention discloses an electrode material for an all-vanadium redox flow battery and a preparation method thereof. The preparation method comprises the following steps of: (1) oxidation treatment of acetylene black: carrying out oxidation treatment on acetylene black by use of air or an oxidant; (2) adsorption of tungstic acid by acetylene black: adding oxidized acetylene black into a solution containing tungstate ions, adding an acid liquid to adjust the pH value to acidity, separating out and adsorbing the tungstic acid on the surface of acetylene black, and aging at room temperature, filtering, washing and drying; and (3) calcination: calcining acetylene black adsorbing tungstic acid, and grinding to obtain the acetylene black supported tungstic oxide electrode material. In the method, oxidation treatment is carried out on acetylene black and then tungsten oxide covers on the surface of acetylene black so as to improve the electrochemical reversibility of acetylene black on the redox couple of the all-vanadium redox flow battery.

A method for producing an ammonium tungstate aqueous solution includes the steps of: adding sulfuric acid to a solution containing tungstate ions; bringing the solution having the sulfuric acid added therein, into contact with an anion exchange resin; and bringing the anion exchange resin into contact with an aqueous solution containing ammonium ions.

The invention discloses a processing method of a tungsten-containing tin concentrate. The processing method comprises the following steps: preparing pulp of the tin concentrate, and mixing the pulp and soluble carbonate to obtain mixed pulp; enabling the mixed pulp to carry out leaching reaction to obtain tungsten-containing leaching residues and a leaching solution; regulating a pH value of the leaching solution to be acid to obtain an acid leaching solution; regulating a pH value of the leaching solution to be alkaline to obtain an alkaline leaching solution; and adding the soluble carbonate in the alkaline leaching solution, and carrying out reaction to obtain artificial scheelite. According to the processing method, tungsten in the tungsten-containing tin concentrate can be converted to tungstate ions depending on the soluble carbonate to enter the leaching solution, thus the method can fully separate tungsten from the tungsten-containing tin concentrate; then, the pH value of the leaching solution is regulated to be acid, thus the tungstate ions in the leaching solution can be removed; while, the pH value of the leaching solution is regulated to be alkaline, full precipitation of the tungstate ions is facilitated, and the artificial scheelite is formed.

The invention belongs to the technical field of ion imprinting, and particularly relates to a preparation method of a tungstate ion-imprinted ceramic membrane and a treatment method for tungsten-containing wastewater. The preparation method of the tungstate ion-imprinted ceramic membrane comprises the following steps of (1) the preparation method of a codeposition ceramic membrane of polymine andpolydopamine; (2) adsorption reaction between the codeposition ceramic membrane of the polymine and the polydopamine and tungstate ions; (3) immersion of a saturated codeposition ceramic membrane intoan ethanol solution of glutaraldehyde, wherein the vacuum processing is conducted for a predetermined time after the reaction is completed; (4) elution of template ions. The tungstate ion-imprinted ceramic membrane prepared by means of the method not only has high adsorption performance for tungstate ions, but also shows excellent selectivity and ultra-fast adsorption rate, the tungstate ion-imprinted ceramic membrane has stable structural performance, imprinted materials on the surface of the ceramic membrane are uniformly distributed, the combination performance of the imprinted materials and the ceramic membrane is good, the imprinted materials do not easily fall off, and the imprinted ceramic membrane is excellent in recyclability.