24 results about "Selenous acid" patented technology

The invention belongs to the field of environmental biotechnology and nano material application, and relates to a method for accelerating microorganisms to reduce selenite based on immobilized riboflavin. Aiming at the problems of poor stability, difficulty in recovery, non-repeated use and the like of dissolved riboflavin serving as an electron shuttle, riboflavin is grafted on the surface of a multi-walled carbon nanotube through a covalent binding method, and immobilized riboflavin capable of being recycled is constructed. The material can accelerate extracellular electron transfer of shewanella MR-1, and toxic sodium selenite is efficiently reduced into low-toxicity or non-toxic elemental selenium. Results show that the immobilized riboflavin not only maintains high reduction activity of riboflavin, but also has excellent cyclic utilization performance, still maintains high reduction rate after being repeated for multiple times, and effectively reduces operation cost and resource loss. According to the invention, an efficient, economical and sustainable application scene is provided for a microorganism-electron shuttle combined remediation technology, and a new thought is also provided for application of a functional nano material in an environmental biotechnology.

The application discloses a treatment method for efficiently removing selenium from waste acid, and specifically comprises the following steps: preheating waste acid to be treated for removing selenium, adding sulfuric acid to adjust the H + concentration of 4-6 mol / L, then adding a reducing agent sodium sulfite Na2SO3, and fully stirring and mixing; controlling the temperature to be 55-70 DEG C to perform a first-stage reaction, then adding a composite catalyst prepared by mixing sodium thiosulfate Na2S2O3 and iodine I2, stirring and mixing, continuing to perform a deep reaction, and performing solid-liquid separation after filtration when the reaction is completed. The application uses sodium sulfite reduction, iodine and sodium thiosulfate catalysis as a substitute for the traditional SO2 reduction mode, solves the problem that the traditional SO2 reduction method is limited by pH liquid, accelerates the reaction rate through iodine and sodium thiosulfate catalysis, simultaneously solves the problem that the traditional sulfite cannot reduce selenium-containing substances other than selenite, and improves the reduction effect of selenium.

The invention relates to a medical product for preventing or correcting selenium deficiency in a patient comprising a solution provided in a flexible container comprising at least one selenium compound in the form of Se(IV), which is preferably selected from the group consisting of sodium selenite, selenous acid and selenium dioxide, characterized in that the solution comprises dissolved oxygen (DO), preferably 0.5 ppm to 8 ppm DO.

The invention discloses a preparation method of soluble selenium glycinate, which comprises the following steps: S1, reacting a selenium source with strong basic hydroxide in water to generate selenite; s2, reacting selenite with glycine and hydrogen peroxide in water for 12-16 hours to generate selenium glycinate; the reaction temperature is 5-15 DEG C, and the reaction needs to be carried out under a dark condition. The selenium glycinate product obtained by adopting the preparation method is stable in content and good in water solubility, the preparation process is simple, the cost is low, the operation is simple and convenient, additional chemical additives are not needed, and the operation steps are reduced; a by-product selenide salt in a chemical reaction can react with hydrogen peroxide to regenerate selenite, and the whole reaction process does not have redundant waste, so that the production concept of green chemistry is met; the product is good in solubility, wider in application field and better in application effect.

This invention discloses an electrochemical method for preparing staggered cuprous oxide micron-sized cubes, belonging to the field of electrode material preparation technology. The method utilizes a redox reaction at room temperature as the main synthesis mechanism, using clean copper foam as the copper source. The reaction is carried out in a mixed solution of alkaline solution and persulfate for a certain time. The copper foam intermediate is then sequentially cleaned, vacuum dried, and calcined. Subsequently, in a three-electrode system, the treated copper foam is used as the working electrode and electrochemically treated in a selenite solution to prepare a highly crystalline cuprous oxide material exhibiting a staggered micron-sized cube morphology with a smooth and flat cube surface. When applied to the energy storage field, it achieves a high areal specific capacity even at high current densities, with a maximum areal specific capacity of 1556 mF / cm². 2 This invention is simple to operate, has a short preparation cycle, is energy-saving, efficient, and inexpensive.

This invention discloses a selenite crystal and its preparation method. X-ray powder diffraction of the selenite crystal, measured using Cu-Kα radiation, yielded diffraction angles (expressed as 2θ) of 17.7°±0.2°, 19.5°±0.2°, 20.0°±0.2°, 22.9°±0.2°, 24.5°±0.2°, 24.9°±0.2°, 26.2°±0.2°, 29.8°±0.2°, 30.2°±0.2°, 31.4°±0.2°, and 33°. Characteristic peaks are observed at 0°±0.2°, 34.3°±0.2°, 35.8°±0.2°, 36.6°±0.2°, 37.4°±0.2°, 37.5°±0.2°, and 38.4°±0.2°. A characteristic endothermic peak is observed at 73.4℃ in the differential scanning calorimetry (DSC) spectrum of the crystal. This invention features a simple preparation route, mild reaction conditions, convenient operation, low cost, and good process reproducibility. The prepared selenite has a stable crystal form, making it suitable for large-scale industrial production of pharmaceutical raw materials.

The invention discloses a method for recovering Se and TeO2 from tellurium-containing crude selenium refining slag, which comprises the following steps of: crushing the tellurium-containing crude selenium refining slag, performing temperature-controlled roasting, decomposing nitrate, and oxidizing tellurium into a high valence state; the roasting slag and a reducing agent are mixed and heated under the vacuum condition, so that the selenium compound is reduced into elemental Se and volatilized, and meanwhile high-valence tellurium is reduced into tetravalent tellurium salt residues; crushing the reduced product, performing water-soluble leaching, and filtering to obtain a solution containing selenite and tellurite and TeO2 precipitate; adding acid into the leaching filtrate to hydrolyze the tellurite salt into TeO2 precipitate, and filtering and separating to obtain TeO2 and selenium-containing filtrate; finally, acid and a reducing agent are added into the selenium-containing filtrate, and selenite is reduced into elemental Se precipitate. The method realizes efficient separation and recovery of selenium and tellurium, is reasonable in process flow and high in recovery rate, and has a good application prospect.

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.

The invention provides a selenium form standard quality control sample in a nut matrix as well as a preparation method and application thereof, and belongs to the technical field of standard substances. The method comprises the following steps: performing primary crushing on seed kernels of Brazil nuts to obtain seed kernel particles; sequentially performing degreasing treatment and secondary crushing on the seed kernel particles to obtain degreased powder; spraying a selenite solution on the degreased powder to obtain composite powder; the composite powder is sequentially subjected to freeze drying, third crushing and mixing, and the selenium form standard quality control sample in the nut matrix is obtained. The standard quality control sample for the selenium form in the nut matrix, prepared by the method disclosed by the invention, has good uniformity and stability, and by adopting the standard quality control sample, the accuracy and the reliability of a content detection result of the selenium form (selenite and / or selenomethionine) in plant products such as nuts can be improved.

The application provides a genipin cross-linked selenium nanoparticle and a preparation method and application thereof, and belongs to the field of functional nanomaterials and intelligent nutrition delivery technology. The preparation method comprises the following steps: dissolving a protein substance in water to obtain a protein solution, adding a selenous acid compound, then adding vitamin C and genipin, performing cross-linking reaction, and performing dialysis on the obtained reaction solution to obtain the genipin cross-linked selenium nanoparticle. The application innovatively uses the concentration of genipin as a control switch, realizes active and accurate control of the release rate of selenium in the intestinal tract, realizes the treatment effect on colitis through instantaneous high-concentration release under a low-concentration selenium administration dose, and effectively solves the defect that the "nutrition-toxicity" dose range of selenium is narrow.

The present invention relates to methods for biological wastewater treatment for Se control in Se-laden wastewater. The Se contaminants in the wastewater include the Se oxyanions selenate (SeO42−) and selenite (HSeO3−), which are biochemically reduced and transformed to elemental selenium (Se0) by microorganisms through anaerobic biological reduction. The resulting Se0 is entrained in the biomass, which is further processed to enable the efficient recovery of concentrated Se0.

This disclosure proposes a lithium selenite / selenium dioxide bilayer-coated ternary material, wherein the chemical formula of the lithium selenite / selenium dioxide bilayer-coated ternary material is LiNi. a Co b Mn c O2·xLi2SeO3·ySeO2, where Li2SeO3 is the inner coating layer and SeO2 is the outer coating layer; where a+b+c=1, 0.6<a<1, 0<b+c<0.4, 0<x<0.3, 0<y<0.1, 0<x+y<0.4.

The application discloses a selenium catalytic synthesis method of polylactic acid in the technical field of material chemistry. L The amount of the substituted selenous acid as the catalyst precursor added into the lactic acid is 0.02-0.08% of the mass of the lactic acid. L The amount of the substituted selenous acid as the catalyst precursor added into the lactic acid is 0.02-0.08% of the mass of the lactic acid. L The amount of the substituted selenous acid as the catalyst precursor added into the lactic acid is 0.02-0.08% of the mass of the lactic acid. 3 The polylactic acid can be obtained by blowing the material into a flow of 0.4-1.0 cm / s air and heating at 160-180 DEG C. The method is simple, and the use of metal catalysts can be avoided, so that metal residues in the product are eliminated, and medical-grade polylactic acid material can be directly prepared.

The invention belongs to the field of recycling of refined copper byproducts, and particularly relates to a selenium recovery method based on copper anode slime, which comprises the following steps: oxidizing selenium element in barrel anode slime into SeO2 through concentrated sulfuric acid, steaming the SeO2 into a spray tower, contacting the SeO2 with spray water, converting the SeO2 into seleninic acid, reducing the selenium into elemental selenium by SO2 which is steamed, and settling the elemental selenium; meanwhile, the graphene is mixed and dispersed in reactants, and based on the structural stability of the graphene under high-temperature roasting, the promotion effect on electron transmission is reserved at the high temperature, so that the electron transfer efficiency of the redox reaction between the concentrated sulfuric acid and the anode slime can be improved, and the recovery rate of the anode slime is improved. Therefore, the conversion evaporation recovery efficiency of selenium in the anode slime is improved.

The invention provides a preparation method of a seleninic acid soap-based microemulsion capable of being infinitely diluted by water, which comprises the following steps of: efficiently emulsifying various liquid oil by taking organic sodium selenite soap as a main emulsifier, fatty alcohol as a co-emulsifier and a composition of the organic sodium selenite soap and the fatty alcohol as an emulsifier to obtain the seleninic acid soap-based microemulsion by a simple preparation method; the obtained seleninic acid soap-based microemulsion can be infinitely diluted by water, and the obtained seleninic acid soap-based microemulsion is low in emulsifier content, good in solubilizing performance and high in stability. The invention further provides a imperative demulsification method of the seleninic acid soap-based microemulsion capable of being infinitely diluted by water, imperative demulsification of the seleninic acid soap-based microemulsion can be realized by changing the pH value of the seleninic acid soap-based microemulsion, a one-solid two-liquid three-phase system is obtained, high-efficiency recovery of organic seleninic acid is realized, and meanwhile, the pH value of the seleninic acid soap-based microemulsion is changed. And the chemical oxygen demand of the residual water phase treated by the activated carbon and the anion exchange resin is extremely low.

The invention discloses a simple preparation and separation method of high-valence selenium and low-valence selenium in the technical field of feeds and fertilizers, which comprises the following steps: by taking elemental selenium and sodium hydroxide or potassium hydroxide as raw materials, generating a mixed solution of sodium selenide and sodium selenite in one step through disproportionation reaction, and then connecting-2-valence selenium to starch molecules through nucleophilic addition reaction to obtain the high-valence selenium and low-valence selenium. The method comprises the following steps: by taking selenium as a raw material, generating a high-stability selenized starch material, and carrying out solid-liquid separation to respectively obtain the selenized starch material and a selenite-containing mother solution, thereby realizing the separation of high-valence selenium and low-valence selenium. The selenized starch material can be used for producing selenium-rich feed, and tetravalent selenium in the solution can be used for producing selenium-rich compound fertilizer. The method has the advantages of short process flow, simple operation, no need of introduction of complex reagents or expensive equipment and low cost, and avoids the regeneration of selenium elementary substance by the neutralization reaction through the separation technology. The method provides a new technical path for realizing high-valued utilization of selenium.

The application provides a selenium form standard quality control sample in a nut matrix and a preparation method and application thereof, and belongs to the technical field of standard substances. The kernel of abalone fruit is first crushed to obtain kernel particles; the kernel particles are sequentially subjected to defatting treatment and second crushing to obtain defatted powder; a selenite solution is sprayed on the defatted powder to obtain composite powder; and the composite powder is sequentially subjected to freeze-drying, third crushing and mixing to obtain the selenium form standard quality control sample in the nut matrix. The selenium form standard quality control sample in the nut matrix prepared by the method has good uniformity and stability, and the use of the standard quality control sample helps to improve the accuracy and reliability of the detection results of the selenium form (selenite and / or selenomethionine) content in plant products such as nuts.

The invention relates to the technical field of preparation of high-purity inorganic compounds, and discloses a rectification purification method for removing trace metal impurities in selenium dioxide, which comprises the following steps: dissolving crude selenium dioxide in an aqueous solvent to form a seleninic acid aqueous solution, adding a chemical reducing agent to regulate the valence state of the impurities, and adding a ferric nitrate auxiliary agent and a hydrolyzable alkaline precursor substance; heating to hydrolyze the precursor substance so as to generate alkali in situ, and realizing homogeneous co-precipitation of iron cations and impurities; the method comprises the following steps: separating precipitates, carrying out thermal dehydration on a purified seleninic acid aqueous solution obtained after separation, and carrying out thermal decomposition removal on residual nitrate anions by heating while crystallizing and separating out selenium dioxide. By selecting ferric nitrate and reusing the heating function of the thermal dehydration step, the problem of secondary pollution of anions caused by conventional ferric salt auxiliaries is avoided.

A method for cleaning a surface of a CdTe-based thin film layer after an activation treatment is provided. The method comprises forming a CdTe-based thin film layer, performing an activation treatment under the presence of an activation agent, and cleaning the CdTe-based thin film layer with a solution comprising selenous acid. Furthermore, a method for forming a photovoltaic device including the method for cleaning a surface of a CdTe-based thin film layer after an activation treatment and a photovoltaic device resulting from this method are provided.

The invention relates to a method for preparing sodium selenite from crude selenium recovered from copper anode slime. The method comprises the following steps: S1, oxidizing: oxidizing the crude selenium recovered from the copper anode slime under the conditions that the temperature is 500-550 DEG C and the oxygen flow is 0.9-1.0 L / min; after the selenium is completely burnt, stopping heating, continuing to introduce O2, and then cooling to room temperature in air to obtain an oxidation product SeO2; s2, separation and purification: fully dissolving the oxidation product SeO2 with deionized water, filtering, heating, evaporating and crystallizing, condensing, re-dissolving, boiling and cooling to obtain a seleninic acid solution; s3, neutralization and crystallization: adding a NaOH solution into the seleninic acid solution for reaction, and performing vacuum drying, standing, cooling and crystallization to obtain crystalline sodium selenite; and S4, heating and dehydrating: heating and dehydrating the crystallized sodium selenite to obtain an anhydrous sodium selenite product. The process is simple in production process, stable and reliable in quality, low in cost and high in economic benefit.

The invention discloses a production device and a production method of selenium gluconate. The production device comprises a base, a reaction kettle is horizontally arranged above the base, a motor is arranged on one side of the reaction kettle, and a belt transmission device is arranged between the motor and the reaction kettle; a Venturi reaction tube is vertically arranged above the reaction kettle close to one end of the belt transmission device; the Venturi reaction tube is sequentially divided into a primary mixing section, a secondary mixing section and a diffusion section from top to bottom; a third liquid inlet is formed in the side wall of the outer circumference of the secondary mixing section, and one end of the third liquid inlet is hermetically connected with a control valve; a hydraulic control device is arranged on one side of the base, and a hydraulic pipe is arranged between the hydraulic control device and the control valve; according to the invention, seleninic acid and gluconic acid are added into a reaction kettle, and a continuous flow reaction technology is adopted, so that the traditional intermittent kettle reaction is successfully converted into continuous production; the invention also adopts a partition temperature control type reaction kettle to realize the gradient accurate control of the reaction temperature.

The utility model relates to a device for preparing selenium dioxide from crude selenium. The device consists of a vacuum drying melting furnace system and an oxidizing furnace system, by arranging the vacuum drying melting furnace and the water vapor condenser, acid radical ions in crude selenium can be removed, and seleninic acid is condensed, collected and returned to a seleninic acid system for retreatment, so that the corrosion of materials to subsequent equipment is reduced, the service life of the equipment is prolonged, and the production cost is reduced. By arranging the buffer tank, waste gas generated in the secondary oxidation process can be dedusted and returned to the seleninic acid system for retreatment, the selenium recycling rate is effectively increased, the purpose of clean production is achieved, and the production cost is reduced; the forehearth generator is arranged at the front section of the oxidation furnace, crude selenium is subjected to first-section oxidation and then subjected to second-section oxidation in the oxidation furnace, the crude selenium is fully oxidized, and the purity of selenium dioxide is high.

This invention provides a method for preparing a selenite-sulfide nanocomposite material. Nickel selenite is grown in situ on nickel-plated carbon cloth using a hydrothermal method, followed by electrodeposition of transition metal sulfides onto its surface. Selenite, as a reinforcing phase in the positive electrode material of a supercapacitor, improves the conductivity of the composite material and releases selenate ions, which, along with sulfate ions released from the sulfides, adsorb onto the material surface, promoting redox kinetics in the electrochemical process. The prepared selenite-sulfide composite nanoelectrode material exhibits excellent supercapacitor performance at a current density of 1 A g. ‑1 At that time, its specific capacity was 3509 F g. ‑1 An asymmetric supercapacitor composed of commercially available activated carbon at 844 W / kg ‑1 The power density reached 141Wh / kg. ‑1 High energy density. This supercapacitor exhibits good cycle stability at 5A g. ‑1 Under these conditions, after 25,000 cycles, the capacity retention rate was 100.2%.

The invention provides genipin cross-linked selenium nano-particles and a preparation method and application thereof, and belongs to the technical field of functional nano-materials and intelligent nutrition delivery, the preparation method comprises the following steps: dissolving a protein substance in water, hydrating to obtain a protein solution, adding a seleninic acid compound, then adding vitamin C and genipin, and uniformly stirring to obtain the genipin cross-linked selenium nano-particles. And carrying out a cross-linking reaction, and dialyzing the obtained reaction liquid to obtain the genipin cross-linked selenium nanoparticles. The genipin concentration is innovatively used as a regulation switch, active and accurate control over the release rate of selenium in the intestinal tract is achieved, namely, the treatment effect on colitis can be achieved through instant high-concentration release under the condition of the low-concentration selenium administration dosage, and the defect that the nutrition-toxicity dosage range of selenium is narrow is effectively overcome.