20results about "Elemental selenium/tellurium" patented technology

The application provides a method for separating selenium tellurium from high-selenium tellurium dioxide through multistage conversion, and belongs to the technical field of non-ferrous metallurgy. The method comprises the following steps: a, material preparation; b, primary conversion leaching: selectively reducing selenium in a solution containing a reducing agent at pH 8-11 to obtain a selenium tellurium-containing residue and a primary leaching solution; c, secondary conversion leaching: selectively leaching tellurium in a strong alkaline solution containing a reducing agent to obtain elemental selenium and a secondary leaching solution; and d, neutralization treatment: combining the two leaching solutions and adding acid to obtain high-purity tellurium dioxide. The method is simple to operate, short in production cycle, and realizes efficient separation of selenium tellurium. The purity of the obtained elemental selenium is greater than or equal to 95%, the purity of the obtained tellurium dioxide meets the requirements of electrodeposition for producing 4N tellurium, and the method is suitable for large-scale production.

The application relates to an ultrasonic treatment method of high-impurity copper anode slime. The ultrasonic treatment method is realized through hierarchical ultrasonic strengthening and synergistic leaching. In the first-stage leaching, hydrogen peroxide-oxygen-rich air composite oxidants are combined with ultrasonic cavitation effects to realize efficient oxidation leaching of arsenic, antimony and bismuth; in the second-stage leaching, sulfuric acid-sodium sulfite mixed leaching agents are used to remove harmful impurities such as arsenic, antimony and bismuth under ultrasonic strengthening, and to efficiently enrich valuable metals such as gold, silver, selenium and tellurium, so that the treatment period is shortened, energy consumption and reagent consumption are reduced, resource comprehensive utilization is improved, and the method is suitable for efficient separation and resource recovery of high-impurity copper anode slime containing refractory impurities such as arsenic, antimony and bismuth and valuable metals such as gold, silver, selenium and tellurium.

This invention relates to the field of electrocatalysis technology, specifically to a single-element selenium-nickel-iron alloy composite electrocatalyst, its preparation method, and its application. Using nickel chloride, ferrous sulfate, urea, ammonium fluoride, and selenium dioxide as precursors, a two-step hydrothermal method is employed. In the first step, a nickel-iron alloy is prepared in situ on a foamed iron substrate using nickel chloride, ferrous sulfate, urea, and ammonium fluoride precursors. In the second step, selenium dioxide is used as a selenium source to composite elemental selenium with the nickel-iron alloy, resulting in the in-situ growth of a single-element selenium-nickel-iron alloy block catalyst on a foamed iron substrate. The electrocatalyst of this invention exhibits excellent catalytic activity and stability in the electrocatalytic water desorption oxygen reaction, meeting the requirements for large-scale industrial applications.

The application relates to the technical field of non-ferrous metal smelting and recycling, and discloses a method for reducing and separating selenium in acid sludge wet leaching liquid, which comprises the following steps: acid sludge chlorination leaching and rough selenium residue and post-depletion liquid generated by a step of reducing rough selenium from the leaching liquid; treating the post-depletion liquid through a neutralization and mercury precipitation step; mixing the rough selenium residue and the post-depletion liquid to perform alkaline leaching, adding NaOH to adjust the mass concentration to 10-20%, adding 1.05-1.20 times of the required amount of hydrazine hydrate under normal temperature and pressure, and separating an Se 2‑ alkaline leaching liquid; adding 1.0-1.15 times of the required amount of hydrogen peroxide to the Se 2‑ alkaline leaching liquid to perform oxidation and precipitate selenium, and separating a powder selenium product. Through the application, the side reaction dissolution of lead impurities is effectively inhibited, efficient separation of selenium and lead and mercury is realized, reagent consumption is reduced by combining with mother liquor circulation, and finally a high-purity powder selenium product is prepared.

The present application relates to non-ferrous metallurgy and secondary resource comprehensive utilization field, disclose a kind of acid mud selenium and mercury cascade separation and recovery method, by adjusting acid mud leaching solution total chloride concentration to 3.5 to 4.5mol / L, using coordination effect will mercury ion be converted into stable mercury chloride complex ion, significantly negative shift mercury's conditional electrode potential;Crude selenium seed and modified sodium lignosulfonate are introduced into the system, and an organic modification layer with steric hindrance effect is constructed on the surface of the seed;By adding reducing agent in stages and combining online ORP feedback control, induce elemental selenium to heterogeneously precipitate under the guidance of the modification layer, and convert from amorphous red selenium to hexagonal gray selenium through high-temperature curing;After solid-liquid separation, dilute the selenium-removed solution to promote the dissociation of mercury chloride complex ion, and then adjust the acidity and precipitate and recover mercury. The present application realizes the selective and deep separation of selenium and mercury, improves the product purity and the material filtration performance, and realizes the closed circuit circulation of process materials.

This invention provides a nano-tellurium / carbon composite material and its preparation and application. The nano-tellurium / carbon composite material comprises reduced graphene oxide and tellurium nanorods dispersed within the reduced graphene oxide; the tellurium nanorods are embedded within the reduced graphene oxide. This invention uses tellurium hydride as a reducing agent and tellurium source, and GO as an oxidant and loading material, resulting in a uniform distribution of tellurium nanorods within the rGO composite material, overcoming the problems of easy agglomeration and uneven dispersion of nano-tellurium materials. The composite material preparation method of this invention requires only a simple one-step process and can be completed in a short time, solving the problem of complex synthesis processes for various nano-tellurium / carbon composite materials, which is beneficial for the large-scale production of this composite material. Furthermore, this invention uses PVP as a surfactant, which results in the formation of small tellurium nanorods during the reaction process.

This invention relates to a method for removing non-metallic impurities of carbon and oxygen from high-purity selenium, belonging to the field of high-purity selenium purification technology. The invention provides a method for removing non-metallic impurities of carbon and oxygen using high-purity selenium. The method involves vacuum distilling 99.999% high-purity selenium with a metal (or metal mixture) reducing agent under argon atmosphere while maintaining the temperature at 400℃ for 120 minutes. The carbon content in the resulting selenium volatiles is reduced from 0.0024% to <0.0001%, and the oxygen content is reduced from 0.011% to 0.0066%. The method described in this invention is simple, safe, controllable, and easy to operate.

This invention provides a nano-selenium, its preparation method, and its applications, relating to the field of nano-selenium fertilizer technology. Using sodium selenate or sodium selenite as raw material A and thiol-functionalized graphene as raw material B, raw material A and raw material B are mixed and reacted for a certain period to obtain nano-selenium, which can be used in fertilizers, food anti-oxidation and preservation, industrial catalysis, or chemical analysis. This invention uses inorganic selenium and thiol-functionalized graphene as raw materials. Through a simple solution mixing, reaction, and settling process, the in-situ reduction of selenite by thiol-functionalized graphene and the stable loading of nano-selenium are achieved, completing the conversion from inorganic selenium to nano-selenium in one step without the need for reducing agents.

The application provides a method for preparing 6N selenium from 2N selenium, and belongs to the field of high-purity metal preparation.The method comprises the following steps: oxidizing and roasting 2N selenium to obtain selenium dioxide vapor; mixing the selenium dioxide vapor with water to perform a combination reaction to obtain a selenite solution; mixing the selenite solution with a reducing agent to perform a reduction reaction to obtain 3N and / or 4N selenium; melting the 3N and / or 4N selenium, and then immersing a crystallizer into the obtained melt to perform rotary crystallization to obtain 6N selenium.The application roasts selenium with oxygen to generate selenium dioxide to remove high-boiling impurities; the selenium is enriched by using the property that selenium dioxide is easily soluble in water, the impurities (such as selenium dioxide) that are difficult to dissolve in water are removed to realize the purification of selenium; the 3N and / or 4N selenium is further purified by rotary crystallization to realize the further purification of selenium.

This invention belongs to the field of nanomaterial preparation technology, specifically disclosing a method for preparing ultrasmall selenium nanomaterials using physical vapor deposition (PVD) and its applications. This method involves placing selenium powder and sodium chloride in a tube furnace and performing gradient temperature-controlled vapor deposition under an inert gas environment to prepare ultrasmall selenium nanomaterials with a particle size of 2-5 nm. Compared to traditional solution methods, this process avoids the use of organic solvents, and post-processing only requires dissolution and centrifugation purification. It has advantages such as large-scale production capability, high product purity, and short preparation time (30 min), making it suitable for large-scale production. The ultrasmall selenium nanomaterials prepared by this invention have significant application potential in sodium-ion batteries, optoelectronic devices, immunotherapy, and selenium fertilizers (quantum dot selenium bio-fortifiers).

The present application relates to a kind of selenium monatomic nanoscale enzyme, the selenium monatomic nanoscale enzyme includes hollow ball and particle, the hollow ball includes titanium, the particle includes selenium, the particle is doped in hollow ball.The preparation method of the selenium monatomic nanoscale enzyme includes the following steps: taking hollow ball raw material to be prepared into hollow ball, inert gas is continuously passed into heating device, according to mass ratio, hollow ball and particle raw material are taken, hollow ball is placed in one side of the heating device, hollow ball is heated, particle raw material is placed in the other side of the heating device, particle raw material is heated by gradient temperature rise, heating is maintained, cooling, obtain selenium monatomic nanoscale enzyme.Selenium monatomic nanoscale enzyme using the present application can effectively improve the conductivity of sound sensitizer, enhance the mobility of electron, reduce the recombination probability of electron hole pair, significantly reduce the band gap of sound sensitizer, improve the generation efficiency of ROS.

This invention discloses an enhanced leaching and purification method for tellurium in arsenic-antimony-tellurium alkaline slag, belonging to the field of solid waste resource utilization and rare and dispersed metal extraction in non-ferrous metal smelting. Using high-arsenic-antimony-tellurium alkaline slag as raw material, a mixed leaching method with tellurium-directed leaching agents is employed. Through the synergistic effect of "strong alkali complexation-reduction solubilization-high salt stable solubility," efficient tellurium leaching and directional retention of arsenic and antimony are achieved, resulting in a low-impurity tellurium-containing solution after solid-liquid separation. After pH adjustment, a one-step tellurium purification agent is added for reduction purification, directly preparing high-grade elemental tellurium. This invention overcomes the limitations of traditional step-by-step processes, with high tellurium recovery as the core technical objective, achieving efficient separation and one-step purification of tellurium from arsenic and antimony: tellurium leaching rate ≥95%, reduction purification rate ≥98%, total recovery rate ≥93%, product grade ≥99.5%; arsenic and antimony leaching rates ≤3.5% and ≤5.0%, respectively. The leaching residue and purified liquid can be recycled. The process is short, the reagent consumption is low, it is compatible with conventional equipment, and it is suitable for industrial promotion.

This invention belongs to the field of magnetic materials technology, and discloses an atmospherically stable two-dimensional room-temperature ferromagnetic nanosheet, its preparation method, and its applications. The chemical formula of the two-dimensional ferromagnetic nanosheet is Cr. 1+δ Te2, where 0.65≤δ≤0.75. The two-dimensional ferromagnetic nanosheets exhibit room-temperature magnetism and stability in morphology and magnetic domain changes under atmospheric conditions. The initial magnetic domains of the two-dimensional ferromagnetic nanosheets are striped domains. This invention successfully prepared atmospherically stable Cr with room-temperature magnetism using a chemical deposition method. 1+δ Te nanosheets enable the controllable growth of two-dimensional room-temperature magnetic materials. The initial magnetic domains of the prepared nanosheets are striped domains, and the generation and annihilation of skyrmions can be controlled under the influence of an external magnetic field and thermal excitation. This material has broad application prospects in the fields of magnetic information storage and spintronic devices.

This utility model relates to the field of tellurium ingot casting technology, and specifically discloses a tellurium ingot casting device, including a furnace, a chute, a casting sump, and a casting machine platform. The furnace includes a crucible, a cover plate, insulating bricks, a heating device, a thermocouple, a first outer shell, a support, a rotating shaft, a connecting shaft, a leak detection port, and a pressure cap. The furnace is mounted on the support and connected by the rotating shaft. The cover plate is connected to the first outer shell through the connecting shaft. The first outer shell is made of stainless steel. The leak detection port is located on the side of the furnace near the chute. The crucible is made of silicon carbide graphite and is fixed to the first outer shell by the pressure cap. The insulating bricks and the heating device are located between the crucible and the first outer shell. This utility model adopts a two-stage zoned temperature-controlled melting and impurity removal method from bottom to top. Impurities easily float to the surface and solidify, resulting in good stratification with the molten tellurium. The impurity removal effect is good, the operation is simple, and the tellurium yield is high. The entire operation process is controlled by PLC, with a high degree of automation, avoiding frequent contact between operators and the high-temperature molten material, and creating a friendly working environment.

The utility model relates to metallurgical technical field discloses a device for selenium tellurium separation extraction refined selenium, including base, the base upper end one side fixed mounting is used for carrying out oxidation reduction reaction's reaction kettle, the reaction kettle upper end face one side fixedly connected with the storage kettle for storing oxidizing agent, the base upper end face fixedly connected with the gas extraction assembly for absorbing the gas in reaction kettle. The utility model discloses gas extraction assembly through the gas pump will be excessive sulfur dioxide of oxidation reduction reaction absorption to the processing jar, avoid the acidity of excessive sulfur dioxide and the reaction reverse and carry out, ensure selenium reduction rate, improve the reaction rate, can reduce selenium tellurium coprecipitation and the generation of toxic hydrogen selenide simultaneously, improve refined selenium purity, and the gas absorption to the processing jar can be through the treatment of alkaline treatment liquid and activated carbon board, prevent sulfur dioxide emission pollution processing environment, avoid the harm to the health of operator.

The application discloses a device and a method for preparing high-purity tellurium by directional solidification. The device comprises a furnace body, a gas supply device, a charging device and a tail gas treatment device. The furnace body is arranged outside the charging device. The gas supply device and the tail gas treatment device are connected to two ends of the charging device through gas valves and gas pipelines respectively. The furnace body comprises a plurality of heaters which are arranged in parallel along the length direction of the charging device. The width of each heater is 100-150 mm. The transverse parallel spacing of each heater is 5.0-10 mm. The 5N tellurium ingot is used as the raw material. The tellurium is purified by using a directional solidification technology. The impurities can be fully diffused in the molten liquid phase. The impurity migration efficiency is improved. The purification period is shortened. The 6N high-purity tellurium is prepared.

The application discloses a preparation method of a surface-seleniumized lithium-rich manganese-based positive electrode material, and specifically comprises the following steps: placing lithium-rich manganese-based positive electrode material and selenium powder on both ends of a magnetic boat, and then placing the magnetic boat into a tube furnace, wherein the selenium powder is located at the upstream of the tube furnace, and the lithium-rich manganese-based positive electrode material is located at the downstream; and performing selenization under an inert atmosphere, so as to obtain the surface-seleniumized lithium-rich manganese-based positive electrode material. The application makes full use of the low boiling point of the selenium source, and the selenium source is easy to react with the lithium-rich manganese-based positive electrode material under the inert atmosphere to realize surface selenization. The selenium is distributed in the form of anions on the surface of the lithium-rich manganese-based positive electrode material, and the surface oxygen loss of the selenium can effectively inhibit the surface irreversible oxygen loss, while the bulk phase lattice is not changed, so that the advantages of the bulk phase high capacity are not affected, and the electrochemical problems such as transition metal migration, structure phase transition, voltage and capacity continuous attenuation caused by surface oxygen loss are relieved.

This invention discloses a method for separating and recovering selenium and fixing arsenic in copper anode mud using vacuum roasting, comprising the following steps: a) crushing and screening the copper anode mud to obtain powder; b) uniformly mixing the obtained powder with an iron-based arsenic fixing agent to obtain mixture A; c) placing mixture A in a roasting furnace, then introducing a mixture of inert carrier gas and oxygen-containing gas, and maintaining the system absolute pressure at 1-20 kPa and oxygen partial pressure at 1%-10%, roasting at 400-750℃ for 0.5-4 hours to obtain roasting residue B with arsenic fixed in the form of ferric arsenate and selenium-containing flue gas C; d) passing the selenium-containing flue gas C into a sodium thiosulfate solution for absorption and reduction, and obtaining elemental selenium product D after filtration, washing, and drying; e) leaching the roasting residue B with dilute sulfuric acid to recover the valuable metals copper and silver therein. The above method has a short process flow, good selenium and arsenic separation effect, and can ensure environmental safety in the subsequent valuable metal recovery process.