263 results about "Tellurium dioxide" patented technology

The invention relates to a method for separating tellurium from tellurium slag, which comprises the following steps: firstly, grinding the tellurium slag, leaching out the obtained product in an aqueous solution, purifying and neutralizing a water leaching solution, and producing tellurium dioxide; secondly, performing hydrochloric acid leaching on water leaching residue in a hydrochloric acid system, cooling and filtering an acid leaching solution, and returning acid leaching residue to an anode sludge treatment process; thirdly, performing controlled potential reduction on the acid leaching solution to produce coarse tellurium, and performing roasting and impurity removal on the coarse tellurium and the tellurium dioxide produced by neutralization to obtain pure tellurium dioxide; and fourthly, using the conventional method to reclaim valuable metals such as copper, bismuth, tin, and the like from a reduced solution respectively. The total tellurium leaching rate of the method is as high as more than 98 percent, and the produced coarse tellurium has the advantages of low content of impurity elements, small amount of return slag, small modification amplitude of equipment, short treatment time, and low treatment cost.

A method for extracting metal from bismuth-contained multi-metal material is carried out by leaching out copper and tellurium from bismuth-contained multi-metal by sulfuric acid, adding into chlorinating agent and oxidant to leach out metal bismuth, extracting silver from leaching-out slag with AgCl, PbSO4 and PbC12, adding ammonia water into leaching-out liquid, adjusting pH value to 1.5 to obtain bismuth oxychloride slag with 70% bismuth content, smelting into coarse bismuth by firing method or machining to obtain high-purity bismuth sesquioxide, adjusting pH value to 4.5 by Na2CO3, depositing tellurium to obtain tellurium dioxide and copper-contained solution, and electrically depositing to obtain copper powder with copper-contained content90%. It adopts wetting and firing metallurgical technology, has higher metal recovery rate and excellent leaching-out separation effect and effluent circulating utilization and no environmental pollution.

The invention provides a method for extracting tellurium from tellurium copper slags. The method includes the following steps of (1) sulfating calcination at a high temperature, grinding the tellurium copper slags, mixing ground tellurium copper slags with a concentrated sulfuric acid to calcine, enabling the mass ratio between the concentrated sulfuric acid and the tellurium copper slags to be (1.2-1.5):1, maintaining the calcination temperature in a range from 450 DEG C to 600 DEG C and maintaining the calcination time in a range from 3 hours to 5 hours; (2) alkaline leaching to separate the tellurium, leaching obtained calcination slags by a sodium hydroxide alkaline liquor, and then filtering to obtain a tellurium containing alkali leaching liquid and alkali leaching slags; (3) oxidizing the alkali leaching liquid, oxidizing the tellurium containing alkali leaching liquid by sodium hypochlorite of an oxidant and then filtering to obtain sodium tellurate filtered slags; and (4) acid dissolution reduction, dissolving the sodium tellurate filtered slags by a chloridion containing acidic system, adding a reducing agent to achieve reduction and then filtering to obtain tellurium powders. According to the method for extracting the tellurium from the tellurium copper slags, a complete separation of copper, selenium and tellurium can be fully achieved, a comprehensive recovery of the copper, selenium and tellurium can be achieved, the technological process is simple, tellurium dioxide of an intermediate product is not required, the tellurium powders with a high purity can be directly produced, and the tellurium powders can serve as raw materials of 6N high purity tellurium.

The invention discloses a method for preparing radioactive <124>I ions. The preparation method comprises the following steps: a, taking aluminium oxide powder and tellurium dioxide powder in a mass ratio of 1:18-22, uniformly mixing the powder, and pressing the obtained mixture into a tellurium target with a thickness of 50-60 mg/cm<2>; b, placing the prepared tellurium target in a circular accelerator, and irradiating the tellurium target 2-3 h by Te (p, n) <124>I, wherein the incident p particle beam intensity is 18-20 mu A, the energy is 18.5-20 MeV, and the angle of incidence is 6-10 DEG; meanwhile, cooling the tellurium target by using water in the process of irradiating, and after the irradiating is completed, placing the tellurium target to cool 4-6 h; c, placing the tellurium target in a quartz distillation tube of a destructive distillation device to distill, meanwhile, controlling the temperature to 750 DEG C so as to heat the tellurium target, so that radioactive <124>I ions are escaped, and collecting the radioactive <124>I ions. The problems that radionuclide <124>I prepared in the prior art is low in yield and low in recovery rate are solved.

The invention discloses a preparation method of high purity tellurium. In the method, industrial tellurium of which purity is 99% is used as a raw material and the chemical and physical methods are combined to prepare high purity tellurium. The method comprises the following steps: dissolving the raw material in nitric acid, stirring, heating, filtering, adding the obtained tellurium dioxide in hydrochloric acid, introducing hydrogen peroxide, filtering after dissolving; adding sodium sulfite solution in the filtrate to reduce and obtain 3N-4N of fine tellurium; and dissolving at 400-450 DEG C in hydrogen atmosphere, and adopting the Czochralski purification method to treat fine tellurium and obtain 5N-6N of high purity tellurium. The method has low preparation cost; and the high purity tellurium can be used in the semiconductor material fields such as solar cell, light-emitting diode (LED), thermoelectricity and infrared field.

The invention relates to a method for preparing tellurium dioxide from tellurium slag. According to the technical scheme, the method comprises the following steps of: adding tellurium slag to sulfuric acid solution, stirring at normal temperature, adding 10% oxydol at the temperature of 30-40 DEG C, and then heating to 80-90 DEG C, and leaching under normal pressure; adding copper powder to leachate, carrying out replacement reaction at the temperature of 90-95 DEG C for 2 hours, and carrying out solid-liquid separation to obtain copper telluride slag; adding copper telluride slag to sulfuricacid solution, adding 10% oxydol, stirring at the temperature of 90 DEG C for 1 hour, and filtering; adding sodium carbonate to filtrate for neutralizing the filtrate till pH of the filtrate is 3, and filtering; adding NaOH to filter residue, carrying out alkali leaching and stirring at the temperature of 85-95 DEG C for 1 hour, and filtering; and adding H2SO4 to filtrate for neutralizing the filtrate till pH of the filtrate is 6-7, filtering, washing and drying to obtain a product. The method has the characteristics that: low-grade tellurium-containing material discarded by a copper anode mud production enterprise is used as a raw material to produce high-purity tellurium dioxide, the process is reasonable and pollution-free, and the recovery rate of tellurium is high.

A method of recycling tellurium from anode mud comprises the following steps: a) roasting; b) copper separation; c) gold separation; d) bismuth separation; and e) platinum and palladium separation: mixing bismuth separation residue in the step d) with sulfuric acid, controlling liquid-solid ratio to be 2:1-3:1 and the content of sulfuric acid in the liquid to be 190-210 g/L, stirring the mixture, and adding sodium chlorate to the bismuth separation residue until the bismuth separation residue is white after the bismuth separation residue is pulped, performing solid liquid separation to obtain a platinum and palladium separation residue and a platinum and palladium separation liquid, adding potassium chloride to the platinum and palladium separation liquid, controlling the content of the potassium chloride to be 45-55 g/L, and feeding chlorine to generate potassium chloroplatinate and potassium chloropalladite respectively from the platinum and palladium; and f) tellurium recovery: mixing the platinum and palladium separation residue in the step e) with water, controlling liquid-solid ratio to be 2:1-3:1, adding sodium hydroxide until the pH is 10-11, filtering the liquid, adding diluted sulfuric acid to a filtrate, controlling the pH to be 4.5-5.5 to generate tellurium dioxide, and reducing the tellurium dioxide to prepare tellurium. The method is simple and convenient, and is high in recovery rate and recovery purity of the tellurium.

The invention provides a method for removing deep impurities of coarse tellurium powders, relating to a method for removing deep impurities in the coarse tellurium powders which are recovered from copper anode slimes. The invention is characterized in that in the process of impurity removal, coarse tellurium powders react with nitric acids, which makes the tellurium in the coarse tellurium powders oxidized into the tellurium dioxide and makes impurity elements in the coarse tellurium powders form nitrates to be dissolved into the solution, and after filtering and separation, impurity nitrates are removed; after being washed, filter slimes are dissolved by sodium hydroxide, and solid impurities are obtained by filtering and separation; and the filtrate is added with sulphuric acids for neutralization, and tellurium dioxide powders are obtained after filtering. The method of the invention adopts the nitric acid oxidation impurity removal process, thereby major impurity elements in the coarse tellurium powders can be removed; moreover, the purity of tellurium dioxide powders obtained by the method is more than 99.9 percent.

The invention discloses a method for comprehensively recovering valuable metal from copper tellurium slag. The copper tellurium slag is dissolved by using nitric acid, so that silver, copper and bismuth in the copper tellurium slag are basically dissolved in a solution; tellurium is oxidized into tellurium oxide, thereby entering undissolved slag. Silver, copper and bismuth are separated and recovered via fractional precipitation of the solution; and tellurium is separated and recovered via alkaline leaching of the undissolved slag. The method solves the problems that cost of a conventional process is high, copper recovery rate and tellurium recovery rate are not high, and that silver and bismuth cannot be recovered in the conventional process; influences on the environment of the production process are reduced; a whole process is simple; and pollutions toward the environment is small. The method is simple in the whole production process, low in cost and small pollutions toward the environment, has high comprehensive recovery rate, and realizes complete separation of silver, copper, bismuth and tellurium. The obtained products have high purity; and the recovery rate of silver, copper, bismuth and tellurium is higher than 99%.

The invention relates to a method for recycling tellurium from copper anode slime. The method comprises the following steps of: pre-treating copper anode slime in a mixed solution of sodium chloride, hydrochloric acid and sulphuric acid to remove impurities after ore-grinding; obtaining pre-treated solution and pre-treated slag after solid-liquid separation; carrying out sulfating roasting on the pre-treated slag; removing the copper from the roasted pre-treated slag by adopting a sodium chloride solution; obtaining copper-containing lixivium and copper-removed slag after the solid-liquid separation; separating tellurium from the copper-removed slag and obtaining the tellurium-containing lixivium and tellurium-removed slag after the solid-liquid separation; adding concentrated sulphuric acid to the tellurium-containing lixivium to control the final pH to 6-8; and obtaining the crude tellurium dioxide after neutralizing the tellurium-containing lixivium. In the conventional sodium hydroxide tellurium-leaching process, the tellurium leaching rate is lower than 60wt% and the tellurium content of the leached residue is bigger than 2.00%; and in the tellurium separating process disclosed by the invention, the tellurium leaching rate is higher than 83wt% and the tellurium content of the leached residue is lower than 1.10%, and so the tellurium leaching rate is high, the production period is short, the process is simple and the treatment cost is low.

The invention discloses a recycling method of tellurium in the refrigeration material of bismuth telluride based semiconductor, which comprises the following steps: adding broken and grinded material into fused alkali metal hydroxide or compound of other alkali metal carbonate; proceeding alkali fusing at 640-720 deg. c; adding oxidant; leaching molten substance through water once or twice; neutralizing the leached solution through acid until the pH value is 5-6; obtaining tellurium dioxide; dissolving tellurium dioxide through alkali; obtaining sodium tellurate solution; electrodepositing to obtain the metal tellurium.

The invention relates to a vanadate-system lead-free low temperature sealing glass material and a preparation method thereof. The components of the sealing glass material by mol percentage are as follows: 25 percent to 55 percent of V2O5, 5 percent to 20 percent of B2O3, 5 percent to15 percent of ZnO, 20 percent to 50 percent of TeO2 and 2 percent to 15 percent of an alkali metal oxide R2O. The preparation method of the invention comprises the steps that vanadium pentoxide, boric acid, zinc oxide, tellurium dioxide and alkali metal carbonate are adopted as raw materials; the weight percentages of the raw materials are calculated according to the mol percentage of each component of the sealing glass; the raw materials are then weighted and evenly mixed to be placed in a corundum crucible and fused under the temperature of 800 to 900 DEG C; molten glass is then cast for formation or ground into powder after being treated with water quenching and the powder is then filtered by a 200-mesh sieve. The sealing glass material of the invention contains no toxic and harmful substances such as lead, cadmium, thallium, and the like, and has the advantages of low temperature for sealing, the minimum temperature reaching 300 DEG C, and good chemical stability, and is especially applicable to the sealing of electronic components.

The present invention relates to a terylene air-jet textured yarn fabric with high color fastness and belongs to the technical field of textile. In order to solve a problem of poor color fastness of a fabric in the existing technology, the invention provides terylene air-jet textured yarn fabric with high color fastness. The fabric is mainly weaved from terylene air-jet textured yarn, wherein the terylene air-jet textured yarn is mainly prepared from raw materials of terephthalic acid, glycol monomer, hexamethyldisiloxane, tellurium dioxide, colouring agent, titanium nitride, toner, promoter, dispersant and stabilizer, and the raw materials can also be added with fire retardant or antioxidant. The invention has advantages of high color fastness, uniform coloring and good brightness, and reaches washing resisting color fastness of grade 4-5 , sweat resisting color fastness of grade 4-5 and light resisting color fastness of higher than grade 7; and the raw materials of the invention do not need dyeing after spinning to realize the reduction of environmental pollution, reduction of high temperature dyeing process, and improvement of the strength property of the yarn.

The invention relates to a process for recovering valuable metals in a bismuth-containing material by a selective chloride volatilizing method, and belongs to the technical field of colored metallurgy. The process comprises the following steps of: mixing bismuth-containing powder prepared from the bismuth-containing material, calcium chloride, sodium chloride and water in a ratio of 100:3-6:5-8:7-9, and pelletizing the mixture to obtain dry material balls; carrying out chlorination and volatilization roasting to the dry material balls in a chloridizing volatilization furnace at a temperature of between 600 and 900 DEG C, and desilvering a silver-rich chloride slag after roasting; condensing and absorbing chloride steam generated by the roasting by water or a thin hydrochloric acid solution to obtain a recovery solution; adding bismuth powder in the recovery solution to displace, and obtaining sponge gold powder by filtration; then introducing ammonia and water into a filtrate for hydrolysis to obtain a bismuth chloride oxide, and carrying out de-bismuth further process to the bismuth chloride oxide; adding Na2Co3 in a raffinate to precipitate tellurium to obtain tellurium dioxide; adding a lime cream in a later filtrate generated by the tellurium precipitation and filtration, and stirring and filtering the mixture to obtain basic zinc carbonate; and finally, evaporating and concentrating the filtrate into a concentrated solution to return for mixture pelletizing. The method has the advantages of low requirement on the processed bismuth-containing material, strong adaptability, low cost, simple operation, high recovery rate and the like.

The invention relates to a stainless steel flux-cored wire and a production method thereof. The stainless steel flux-cored wire is characterized in that the stainless steel flux-cored wire is composedof a flux-core and a stainless steel belt, wherein the flux-core is wrapped with the stainless steel belt; the weight of the flux-core accounts for 18-28% of the total weight of the flux-cored wire;and the flux-core comprises, by mass, 15-20% of chromium powder, 10-15% of rutile powder, 5-10% of nickel powder, 4-8% of manganese powder, 4-8% of feldspar powder, 2-4% of aluminum-magnesium alloy powder, 2-4% of molybdenum iron powder, 2-4% of complex nitride, 0.5-2% of complex fluoride, 0.5-1% of bismuth oxide, 0.1-1% of tellurium dioxide, 0.1-1% of cerium oxide, and the balance iron powder, and the sum of the mass percents of the components is 100%. The stainless steel flux-cored wire has the advantages that weld joint forming is attractive, slag removal is easy, splashing is low, an electric arc is stable, no small air hole exists in a weld joint, the amount of fumes in the welding process is small, and meanwhile, the weld joint microstructure further has excellent abrasion resistance, corrosion resistance, crack resistance and fatigue resistance.

The invention discloses a preparation method of a water-soluble CdTe quantum dot, which includes: using cadmium salt as a cadmium source, tellurium dioxide as a tellurium source and sulfhydryl compound as stabilizer, and performing one-step preparation in a water phase system to directly synthetize high-fluorescence and water-soluble CdTe quantum dot. The preparation method has simple steps, used reagents are few, cost is low and the method is easy to implement. The whole production process meets the green and chemical requirements and is safe and environment-friendly. The prepared CdTe quantum dot has high quantum yield and high stability.

The invention discloses a preparation process for the lead-free front electrode silver paste of a solar cell. The process comprises the steps of 1, placing sodium oxide, tellurium dioxide, tungsten trioxide, silicon dioxide, lithium oxide, and oxide additives in a blender mixer to uniformly mix up the materials, placing the above materials in a muffle furnace to fully melt and adulterate the materials, and subjecting the materials to the water-quenching and annealing treatment to obtain the water-quenched glass frit; 2, grinding the water-quenched glass frit obtained in the step 1 in an alcohol system in a planet type grinding machine to obtain glass powder; 3, stirring an organic solvent, ethyl cellulose, butyl cellulose and hydroxy cellulose to obtain a carrier; uniformly mixing up a silver conductive phase, the glass powder obtained in the step 2 and the carrier obtained in the step 3, stirring, grinding and filtering the mixture to obtain the lead-free front electrode silver paste of the solar cell. According to the invention, the performances in the prior art are maintained, while the glass is low in viscosity and good in wettability with other components. After the printing and sintering process of the paste, the paste is good in contractility and does not easily diffuse. Therefore, the fineness of printed graphics is improved.

The invention relates to a waste gas denitration composite catalyst and a preparation method thereof. The waste gas denitration composite catalyst is prepared from a perovskite type catalyst, a catalyst promoter and a catalyst carrier, wherein the formula of the perovskite type catalyst is ABO3, the site A represents a mixture of rare earth metals La (lanthanum) and Y (yttrium), and the site B represents one or a mixture of transition metals Cr (chromium), Mn (manganese), Fe (iron) and Co (cobalt); the catalyst promoter is selected from one or a mixture of SeO2 (selenium dioxide), TeO2 (tellurium dioxide) and PtO2 (platinum dioxide), so as to prevent the deactivation caused by the fact that oxygen atoms in the perovskite type catalyst ABO3 is replaced by sulfur atoms in waste gas; the catalyst carrier is selected from one of TiO2 (titanium dioxide), ZrO2 (zirconium dioxide), SiO2 (silicon dioxide), SnO2 (tin dioxide), Al2O3 (aluminium oxide), zeolite and cordierite; 10g of waste gas denitration composite catalyst is loaded into a fixed bed catalyzing reactor, the NO (nitric oxide)-containing waste gas produced by burning the volatile organic matter is treated at the temperature of 300 DEG C, and the removal rate of NO is 92.9% to 95.8%. The waste gas denitration composite catalyst has the advantages that the water-resistant and sulfur pollution-resistant properties are good, the service life is long, and the running cost is low.

The present invention relates to a method for removing tellurium from crude selenium. Said method is characterized by that it includes the following steps: adding crude selenium into sodium hydroxide solution to make reaction, then making dilution and filtration, introducing air or oxygen gas into the filtrate to make oxidation, using dilute sulfuric acid to regulate pH of solution so as to obtain selenium powder precipitate, filtering, washing and drying so as to obtain selenium powder. The selenium percent recovery can be up to above 95%, purity of selenuim is 95-99% and tellurium content is less than or equal to 0.5%.

The invention relates to a single-crystal tellurium nanotube and a preparation method and application thereof. The preparation method of the single-crystal tellurium nanotube comprises the steps as follows: adding tellurium dioxide and poly vinyl pyrrolidone (PVP) into a glycol solution; agitating and heating the mixture till clarification; continuously heating the mixture to 180-230 DEG C; adding sodium hydroxide into the mixture and agitating for 5-60 minutes at the temperature of 180-230 DEG C to obtain the tellurium nanotube, wherein the weight ratio of the tellurium dioxide, the poly vinyl pyrrolidone (PVP), glycol and the sodium hydroxide is (0.16-0.64):(0.2-0.8):(55-112):(0.05-0.8). The prepared single-crystal tellurium nanotube is 170-460 nanometers in diameter, about 5.0-9.0 microns in length and 30-40 nanometers in wall thickness. The single-crystal tellurium nanotube can service as an in-situ template for compounding PbTe pyroelectricity nanotubes, Bi2Te3 pyroelectricity nanotubes and Sb2Te3 pyroelectricity nanotubes.

The invention relates to a method for recycling tellurium from tellurium anode slime. By adopting the technical scheme, the method comprises the steps that firstly, distilled water is used for washing tellurium anode slime, hydrogen peroxide is used for completely oxidizing uncleaned Na2TeO3 into Na2TeO4, then, sulfuric acid is slowly added into the tellurium anode slime to leach out tellurium, filtering is performed to obtain a tellurium leaching agent, Na2SO3 is used for reducing Te6+ into crude tellurium powder, then, a saltpeter solution is adopted for dissolving the crude tellurium powder, tellurium electrodeposition regularly-discharged liquid waste or tellurium anode mud washing water is added into the solution for neutralization, the pH value of the reaction endpoint is controlled to 5-6, tellurium is totally converted into tellurium dioxide, impurities are removed from the neutralized solution, finally, the tellurium dioxide is dissolved through the tellurium electrodeposition liquid waste, the solution composition is adjusted to meet the requirement of electrodeposition new liquid compositions, and the solution is returned to the electrodeposition process to produce refined tellurium. Tellurium in anode mud produced by tellurium electrodeposition can be supplemented in time for performing process production tellurium refining, the resource utilization efficiency is improved, the technology is reasonable, operation and implementation are easy, and the tellurium recovery rate is high.