Patents
Literature
479 results about "Hexavalent chromium" patented technology
Efficacy Topic
Property
Owner
Technical Advancement
Application Domain
Technology Topic
Technology Field Word
Patent Country/Region
Patent Type
Patent Status
Application Year
Inventor
Hexavalent chromium (chromium(VI), Cr(VI), chromium 6) is any chemical compound that contains the element chromium in the +6 oxidation state (thus hexavalent). Virtually all chromium ore is processed via hexavalent chromium, specifically the salt sodium dichromate. Approximately 136,000 tonnes (300,000,000 lb) of hexavalent chromium were produced in 1985. Additional hexavalent chromium compounds are chromium trioxide and various salts of chromate and dichromate, among others. Hexavalent chromium is used in textile dyes, wood preservation, anti-corrosion products, chromate conversion coatings, and a variety of niche uses. Industrial uses of hexavalent chromium compounds include chromate pigments in dyes, paints, inks, and plastics; chromates added as anticorrosive agents to paints, primers, and other surface coatings; and chromic acid electroplated onto metal parts to provide a decorative or protective coating. Hexavalent chromium can be formed when performing "hot work" such as welding on stainless steel or melting chromium metal. In these situations the chromium is not originally hexavalent, but the high temperatures involved in the process result in oxidation that converts the chromium to a hexavalent state. Hexavalent chromium can also be found in drinking water and public water systems.
Modified chrome corundum ramming material as well as preparation and construction processes thereof
The invention relates to a modified chrome corundum ramming material and a preparation and construction process thereof, and belongs to the technical field of chrome corundum ramming materials. The ramming material comprises a material A, a material B and a material C, wherein the material A comprises chrome corundum aggregate, titanium dioxide coated aluminum oxide microspheres, calcium sulfide dehydrate and silicon carbide porous microspheres; the material B comprises chromium oxide-zirconium oxide composite nano powder, sodium thiosulfate pentahydrate, tricalcium phosphate and hexagonal boron nitride flaky crystals; and the material C comprises an aluminum dihydrogen phosphate-magnesium hydroxide compound, a calcium fluoride-aluminum oxide co-melt and a silane coupling agent. The preparation process comprises the steps of pretreatment of all the components, preparation of composite powder and layered preparation. The construction process comprises the steps of pretreatment, wet-process mixing, layered ramming, negative-pressure permeation, medium-temperature reaction, spraying curing, integral firing and the like. Generation of hexavalent chromium can be effectively inhibited, the thermal shock resistance, the mechanical strength and the heat-conducting property of the material are remarkably improved, and the material has the advantages of being good in environment friendliness, long in service life, excellent in construction performance and the like.
Owner:YING KOU SHI XING REFRACTORY TECH CO LTD
Phenolic resin polymer sphere as well as preparation method and application thereof
The invention discloses phenolic resin polymer spheres as well as a preparation method and application thereof, and belongs to the technical field of heavy metal adsorption in sewage treatment. According to the phenolic resin polymer sphere provided by the invention, the phenolic resin polymer sphere with specific morphology is obtained by improving the synthesis method of the phenolic resin polymer sphere. The adsorption site activity of the phenolic resin polymer sphere can be regulated and controlled in an illumination activation mode, the adsorption capacity and the adsorption efficiency on chromium are remarkably improved by promoting chemical adsorption, and the adsorption capacity and the adsorption efficiency are far higher than those of other chromium adsorbents reported in current literatures; the chromium adsorption capacity is far higher than that of a chromium adsorbent in light condition research. And meanwhile, chemical adsorption under illumination activation can improve the reduction capacity on hexavalent chromium and reduce the toxicity of hexavalent chromium. Moreover, the reduced trivalent chromium is directly adsorbed on the surfaces of the phenolic resin polymer spheres, so that the trivalent chromium does not need to be removed by a precipitation method, and the treatment process of the chromium-containing wastewater is saved.
Owner:JINGDEZHEN CERAMIC UNIV
Ammonia modified porous carbon adsorbent and preparation method thereof
The invention relates to the technical field of adsorbent preparation, in particular to an ammonia modified porous carbon adsorbent and a preparation method thereof. The preparation method of the ammonia modified porous carbon adsorbent comprises the following steps: carrying out hydrothermal acid leaching on gasified fine residues and an acid solution to obtain acid leaching residues; stirring the acid leaching residues in an alkali solution, washing and drying to obtain a porous carbon material; and dipping the porous carbon material in a tetraethylenepentamine solution, and then drying to obtain the ammonia modified porous carbon adsorbent. The ammonia modified porous carbon adsorbent is successfully constructed by taking a porous carbon material derived from coal gasification fine slag as a substrate and further adopting a surface ammonia functionalization modification strategy. The preparation method is simple, the raw materials are easy to obtain, and the prepared ammonia modified porous carbon adsorbent has a good adsorption effect on methylene blue and hexavalent chromium. According to the method, high-added-value resource utilization of the coal gasification solid waste is achieved, and a solution is provided for treatment of the dye wastewater and the heavy metal wastewater.
Owner:YULIN UNIV
Cyanide-free cadmium-iron alloy plating process for high-strength structural steel
The invention discloses a cyanide-free cadmium-iron alloy plating process for high-strength structural steel. The cyanide-free cadmium-iron alloy plating process comprises the step that a nickel-titanium alloy plating layer, a cyanide-free cadmium-iron alloy plating layer and a hexavalent chromium passivation film are sequentially prepared on a high-strength structural steel substrate from inside to outside. The prepared sample piece is subjected to a hydrogen brittleness test according to HB 5067.1-2005 Part 1 of hydrogen brittleness test of plating process: Mechanical Method, and the test result meets the standard requirement; the surface of a plated part is free of white rust after being subjected to an acetate mist test for 400h according to GB / T 10125-2021 Artificial Atmosphere Corrosion Test Salt Spray Test, and a plating layer of the plated part has excellent corrosion resistance; according to GB / T 5270-2005 < GB / T 5270-2005 < GB / T > 5270-2005 < GB / T > 5270-2005 > < GB / T > 5270-2005 > < GB / T > 5270-2005 > < GB / T > 5270-2005 > < GB /
Owner:GUANGZHOU ULTRA UNION CHEM LTD
Carbon-nano zero-valent iron composite material based on coal gasification slag and preparation method of carbon-nano zero-valent iron composite material
The invention discloses a carbon / nano zero-valent iron composite material based on coal gasification slag and a preparation method of the carbon / nano zero-valent iron composite material. The method comprises the following steps: performing component separation on the coal gasification slag to obtain an iron-rich residual carbon component, mixing and grinding the iron-rich residual carbon component and sodium hydroxide according to a specific mass ratio, performing high-temperature calcination treatment in a nitrogen protective atmosphere, and performing hydrothermal activation reaction, solid-liquid separation, washing and drying to obtain the carbon / nano zero-valent iron composite material. The material shows excellent hexavalent chromium removal performance, can realize efficient removal of Cr (VI) in water within 5 minutes (the removal rate reaches 78.9%), and has remarkable structural stability. Synergistic activation of the endogenous iron-carbon components in the industrial solid waste is creatively achieved, a green and environment-friendly novel functional material solution is provided for heavy metal pollution treatment, and the method has important environmental benefits and industrial application value.
Owner:NINGXIA UNIVERSITY
Sewage mixing flocculation sedimentation tank with dosing system and sewage treatment process
PendingCN119735328AWater contaminantsWater/sewage treatment by ion-exchangeAluminium chlorideAluminium chlorohydrate
The invention relates to the technical field of water treatment, and discloses a sewage mixing flocculation sedimentation tank with a dosing system and a sewage treatment process, the sewage treatment process comprises the following steps: (1) sewage enters a pretreatment unit, and large-particle suspended solids are removed; (2) enabling the sewage to flow into a pH regulating tank, adding a pH regulator through a dosing system, and regulating the pH value to 9-11; (3) passing through a coagulation reaction tank, adding ferrous sulfate to reduce hexavalent chromium into trivalent chromium, and promoting a flocculation reaction; and (4) further adding polyaluminum chloride through the flocculation reaction tank to form floc. Through a multi-unit combined treatment process, suspended solids and various heavy metals in the sewage are gradually removed, and the effluent quality is ensured to reach the standard. Compact and reasonable process layout is adopted, the occupied area is reduced, and the device is suitable for small and medium-sized sewage treatment plants. An automatic dosing control system is introduced, dosing is accurate, and the operation cost is reduced.
Owner:ZHEJIANG HYDROPOWER ARCHITECTURE JICHU ENG CO LTD
Device for treating wastewater containing hexavalent chromium ions
ActiveCN224105627UWater contaminantsWater/sewage treatment by electrochemical methodsCathodic reactionPorous carbon
The utility model discloses a device for treating wastewater containing hexavalent chromium ions, which comprises an anode reaction zone, a cathode reaction zone, a buffer zone, an electrocoagulation reaction zone and an inclined tube settling zone which are communicated in sequence, a suspended partition plate is arranged between the anode reaction zone and the cathode reaction zone, a graphite plate array is arranged in the anode reaction zone, and the graphite plate array is arranged in the inclined tube settling zone. A porous carbon material is arranged in the cathode reaction zone, the cathode reaction zone is communicated with the buffer zone, the buffer zone is communicated with the electrocoagulation reaction zone, an iron pole plate array is suspended in the electrocoagulation reaction zone, the electrocoagulation reaction zone is communicated with the inclined tube settling zone, and the inclined tube settling zone is communicated with the inclined tube settling zone. And an inclined tube is suspended in the inclined tube settling region. According to the utility model, hexavalent chromium ions in water can be removed by only using electricity and a small amount of iron element, reducing agent chemicals and acid and alkali agents used for treating hexavalent chromium in the traditional process are greatly reduced, and the salt content of effluent is far lower than that of the traditional treatment process.
Owner:SHANGHAI TETRELS MATERIAL TECH CO LTD
Application of ammonia modified porous carbon adsorbent in Cr (VI) adsorption
The invention relates to the technical field of adsorbent preparation and hexavalent chromium Cr (VI) adsorption, in particular to application of an ammonia modified porous carbon adsorbent in Cr (VI) adsorption. According to the method, an ammonia modified porous carbon adsorbent is added into a water sample containing Cr (VI) for adsorption, so that Cr (VI) in the water sample is removed; the preparation method of the ammonia modified porous carbon adsorbent comprises the following steps: carrying out hydrothermal acid leaching on gasified fine residues and an acid solution to obtain acid leaching residues; stirring the acid leaching residues in an alkali solution, washing and drying to obtain a porous carbon material; and dipping the porous carbon material in a tetraethylenepentamine solution, and then drying to obtain the ammonia modified porous carbon adsorbent. The ammonia modified porous carbon adsorbent is successfully constructed by taking a porous carbon material derived from coal gasification fine slag as a substrate and further adopting a surface ammonia functionalization modification strategy. The ammonia modified porous carbon adsorbent has a good adsorption effect on Cr (VI).
Owner:YULIN UNIV
Stirring and heating device and method for measuring hexavalent chromium in soil and sediment
The invention discloses a stirring and heating device and method for measuring hexavalent chromium in soil and sediment, the stirring and heating device comprises a stirring and heating cabin and a power cabin, a stirring and heating cabin cover is arranged above the stirring and heating cabin, a magnetic stirring device and a driving motor are arranged in the power cabin, and a beaker bracket and a heating pipe are arranged in the stirring and heating cabin; the heating pipe is located on the inner bottom face of the stirring and heating cabin, the beaker bracket is located above the heating pipe, stirring and heating cabin cover open holes and a stirring and heating cabin cover handle are arranged above the stirring and heating cabin cover, and the number and the position of the stirring and heating cabin cover open holes correspond to those of the beaker bracket. The lower end of the central rotating shaft is connected with an output shaft of the driving motor, the upper end of the central rotating shaft penetrates through the central position of the stirring and heating cabin cover, and an infrared temperature measuring device is arranged at the upper end of the central rotating shaft. The method can effectively improve the detection efficiency and precision of hexavalent chromium in soil and sediments.
Owner:SHANDONG METALLURGY QUALITY TESTING TECH SERVICE CENT
Method for cooperatively treating chromium-containing sludge by using waste dust collecting cloth bags and blast furnace dust
The invention relates to a method for cooperatively treating chromium-containing sludge by using a waste dust collecting bag and blast furnace dust. The method comprises the following steps: roasting the waste dust collecting bag to obtain roasted ash of the waste dust collecting bag; mixing the roasting ash and blast furnace fly ash; adding the mixed material 1 into the chromium-containing waste liquid, and carrying out plate-frame pressure filtration to obtain a mixed material 2; the method comprises the following steps: cutting iron ore into blocks, drying, roasting after drying, quickly water-cooling a roasted product, grinding after water-cooling, and magnetically separating a ground product to obtain spinel iron ore concentrate containing ferrochrome and low-chromium tailings. According to the method, the waste dedusting cloth bag and the blast furnace dedusting ash are used as curing agents, curing of heavy metal chromium in the chromium-containing sludge is achieved, the leaching rate of hexavalent chromium and total chromium in the obtained product is far lower than the standard limit value, harmless treatment of the chromium-containing sludge is achieved, the purpose of treating waste with waste is achieved, the obtained ferrochrome spinel can be recycled through magnetic separation, and the method is environmentally friendly. The produced low-chromium tailings can be directly buried or used as building materials.
Owner:ANGANG STEEL CO LTD
Preparation method of defect-rich Bi4NbO8Cl-C composite photocatalyst
PendingCN120502342AWater treatment compoundsWater/sewage treatment by irradiationIndustrial waste waterEcological environment
Hexavalent chromium (Cr (VI)) is widely applied to the industries of electroplating, spinning, leather tanning and chromium product manufacturing, and Cr (VI)-containing sewage has very strong biotoxicity and mutagenicity. Therefore, effective removal of Cr (VI) in industrial wastewater has important significance for protecting ecological environment and human health. As a novel bismuth-based oxychloride photocatalyst, the Bi4NbO8Cl material with the Aurivillius-Sillen structure has the advantages that the unique layered molecular structure of the Bi4NbO8Cl material is beneficial to the separation of photon-generated carriers, and the Bi4NbO8Cl material has good photocatalytic performance. On the basis of a Bi4NbO8Cl visible light response photocatalyst, the concentration of a glucose solution is regulated and controlled, carbon shell layers with different thicknesses are loaded, meanwhile, oxygen vacancy defects with different concentrations are formed, the visible light response Bi4NbO8Cl (at) C composite photocatalyst is obtained, and a good effect is achieved when the visible light response Bi4NbO8Cl (at) C composite photocatalyst is used for treating Cr (VI)-containing wastewater under the acidic condition.
Owner:QINGDAO UNIV OF SCI & TECH
Surface-treated steel sheet and method of producing same
Provided is a surface-treated steel sheet that can be produced without the use of hexavalent chromium and that combines excellent film corrosion resistance, coating corrosion resistance, film wet adhesion, coating secondary adhesion, and weldability. At least one side of the surface-treated steel sheet includes a Ni-containing layer, a metallic Cr layer on the Ni-containing layer, and an oxidized Cr layer on the metallic Cr layer. The water contact angle is 50° or less, and the total atomic ratio to Cr of K, Na, Mg, and Ca adsorbed on the surface is 5.0% or less.
Owner:JFE STEEL CORP
Remediation method of hexavalent chromium polluted underground water
The invention provides a remediation method for hexavalent chromium polluted underground water, and relates to the technical field of water treatment. According to the preparation method, rice hulls are adopted as raw materials and treated through an oxygen-limited pyrolysis-ferric salt dipping composite technology, and the rice hull-based iron-rich biochar material is obtained; loading microorganisms with the rice hull-based iron-rich biochar material to obtain an adsorption material; the adsorption material is used for carrying out adsorption treatment on the hexavalent chromium-containing polluted underground water. Aiming at Cr (VI) polluted underground water, a prepared rice husk-based iron-rich biomass material is adopted to load domesticated soil indigenous microorganisms, and the domesticated soil indigenous microorganisms are added into a nearly neutral Cr (VI) polluted soil / underground water reaction system, so that efficient reductive degradation of Cr (VI) is realized, and the influence mechanism of Fe < 3 + > is explored.
Owner:CHINA UNIV OF MINING & TECH
Remediation agent for high-concentration hexavalent chromium contaminated soil and preparation method and remediation method thereof
The invention discloses a remediation agent for high-concentration hexavalent chromium polluted soil and a preparation method and a remediation method thereof, and belongs to the technical field of soil pollution remediation. The remediation agent for the high-concentration hexavalent chromium contaminated soil comprises an acidic precursor, an iron-sulfur reducing agent and a synergist, the acidic precursor comprises organic acid and propylene glycol alginate; the iron-sulfur reducing agent comprises an iron-based reducing agent and a sulfur-based reducing agent; the synergist is prepared from sophorolipid and alkyl glucoside. The remediation agent can be used for high-concentration hexavalent chromium contaminated soil, hexavalent chromium in the soil is exposed in a Cr < 6 + > ion form as much as possible by replacing the hexavalent chromium in the soil, then the hexavalent chromium is converted into trivalent chromium by using a reducing agent, and the removal efficiency of the hexavalent chromium reaches up to 99.6%. In addition, the soil remediation agent is simple in use mode, rapid and thorough in reaction and lasting in effect.
Owner:LINYI UNIVERSITY +1
Electrophoretic coating with high weather resistance and high salt mist resistance and preparation method thereof
The invention belongs to the technical field of coating compositions, and discloses an electrophoretic coating with high weather resistance and high salt mist resistance and a preparation method thereof. According to the coating, a composite pigment and filler system formed by compounding a surface-modified sheet-shaped physical shielding filler and a calcium / zinc double-ion exchange type corrosion inhibition filler is adopted, and the surface-modified sheet-shaped physical shielding filler forms a compact labyrinth structure to prolong a corrosion medium permeation path; the corrosion inhibition filler releases Ca < 2 + > / Zn < 2 + > under the stimulation of chloride ions to generate a composite precipitation membrane in situ to block electrochemical corrosion; the two components are co-ground and pre-dispersed and chemically bonded with a resin matrix through a silane coupling agent, so that the compactness, the adhesive force and the self-repairing capability of the coating are improved. The electrophoretic coating does not contain hexavalent chromium and is suitable for high-end protection scenes such as automobiles and ocean engineering.
Owner:SHANGHAI WEITU ENVIRONMENTAL PROTECTION NEW MATERIALS CO LTD
Dry-process clinker cement and preparation process thereof
The invention relates to the technical field of cement preparation, and particularly discloses dry-process clinker cement and a preparation process thereof. The dry-process clinker cement comprises the following raw materials in parts by weight: 180-200 parts of limestone; 30-50 parts of iron tailing powder; 20 to 30 parts of coal gangue; 10 to 20 parts of fly ash; 5-8 parts of calcium fluoride; 5-8 parts of nano silicon dioxide; 1-5 parts of nano calcium carbonate; 1-5 parts of sodium sulfide; 1-5 parts of a charcoal-ferrous sulfate loading material; 100 to 200 parts of water; 5-20 parts of a sintering aid; the biochar-ferrous sulfate loading material is obtained by loading ferrous sulfate on biochar particles. According to the dry-process clinker cement disclosed by the invention, the reduction activity and chromium removal efficiency of the ferrous sulfate can be effectively enhanced through the charcoal-ferrous sulfate loading material, so that hexavalent chromium in the cement can be efficiently removed by using a relatively small amount of ferrous sulfate, and the cement can keep relatively good compressive strength while the cost is reduced.
Owner:TONGCHUAN YAOBAI SPECIAL CEMENT CO LTD
Hexavalent chromium solidification method suitable for acid / alkali soil
The invention discloses a hexavalent chromium solidification method suitable for acid / alkali soil, hexavalent chromium in the acid / alkali soil is solidified through combination of a low-carbon binding material and glucose, and the method comprises the following steps: mixing hexavalent chromium polluted soil with the low-carbon binding material, an exciting agent and a reducing agent, adding water, and uniformly stirring to obtain a mixture; the mixture is subjected to mold entering, forming, demolding and curing in sequence, and curing is completed; wherein the low-carbon cementing material comprises high-calcium fly ash, carbide slag and desulfurized gypsum; the exciting agent is silica fume water glass; the reducing agent is glucose. The solidified body prepared by the method can be used as a roadbed material, the purpose of treating waste with waste is achieved while hexavalent chromium is effectively prevented from being leached, and the defects of high carbon footprint, secondary pollution and the like of a traditional repairing means are overcome.
Owner:SOUTHEAST UNIV
A remediation composition for hexavalent chromium-contaminated soil and a soil remediation method
The present invention provides a remediation composition for soil contaminated with hexavalent chromium and a soil remediation method. The composition comprises catechin, flavonoid isorhamnetin and humic acid with a mass ratio of 1:1 - 3:0.1 - 1. The remediation composition for soil contaminated with hexavalent chromium according to the present invention can achieve a leaching rate of 93% for the hexavalent chromium contamination in the soil. At the same time, the composition can reduce more than 95% of the hexavalent chromium in the leaching solution to trivalent chromium with low toxicity, achieving the purpose of completely removing hexavalent chromium from the soil and greatly reducing the material cost of chemical leaching.
Owner:TIANJIN POLYTECHNIC UNIV
Method for detecting heavy metal trivalent antimony ions / hexavalent chromium ions in environment based on color developing agent
ActiveCN119780079AMaterial analysis by observing effect on chemical indicatorColor/spectral properties measurementsActive agentPhysical chemistry
The invention discloses a method for detecting heavy metal trivalent antimony ions / hexavalent chromium ions in an environment based on a color developing agent, and belongs to heavy metal ion detection.The method comprises the following steps that a sample to be detected is taken, and acid liquor is added to adjust the pH value of the sample to be detected; adding a color developing agent and a surfactant into the to-be-detected solution, mixing, and standing; after full reaction, the absorbance is measured through a spectrophotometric method, the measured absorbance value of the trivalent antimony ions / hexavalent chromium ions corresponds to the standard curve, and the concentration of the trivalent antimony ions or hexavalent chromium ions in the to-be-measured sample is obtained. Sb < 3 + > / Cr < 6 + > reacts with a color developing agent to generate a stable orange complex, and the stable orange complex has the characteristics of low detection limit and high sensitivity to trivalent antimony ions and hexavalent chromium ions. In addition, the method does not depend on large instruments and equipment, and is simple, efficient and convenient to operate.
Owner:NANJING NORMAL UNIVERSITY
Method for solidifying harmful components in hazardous wastes
The invention relates to a method for curing harmful components in hazardous wastes, which comprises the following steps: uniformly mixing high-silicon iron tailings and blast furnace fly ash, adding the mixed material into chromium-containing waste liquid, stirring, carrying out plate-frame pressure filtration, carrying out pressure filtration again to obtain a mixed material, cutting the mixed material into blocks, drying the cut mixed material, and roasting after treatment to obtain a roasted product; carrying out rapid water cooling on the roasted product, and grinding after water cooling; and performing magnetic separation on the grinding product to obtain iron ore concentrate containing ferrochrome spinel and low-chromium tailings. According to the method, solid waste high-silicon iron tailings and blast furnace fly ash generated by iron and steel enterprises are used as curing agents, curing of heavy metal chromium in the chromium-containing sludge is achieved, the leaching rate of hexavalent chromium and total chromium in the obtained product is far lower than the standard limit value, harmless treatment of the chromium-containing sludge can be achieved, and the method is suitable for industrial production. The obtained ferrochrome spinel can be recovered through magnetic separation, and the generated low-chromium tailings can be directly subjected to landfill treatment or used as building materials.
Owner:ANGANG STEEL CO LTD
Rolled copper foil and surface treatment process thereof
The invention relates to the field of rolled copper foil preparation, in particular to rolled copper foil and a surface treatment process thereof. According to the method, the process is optimized, and toxic hexavalent chromium electroplating is replaced by optimizing the passivation step and electroplating the Zn-Ni-Mo alloy layer, so that the safety and environmental friendliness are improved, meanwhile, the heat resistance and oxidation resistance of the rolled copper foil are improved, and the requirements of industrial manufacturing are met.
Owner:ZHEJIANG GARDEN NEW ENERGY CO LTD
Sodium vanadium solution treatment method
The invention relates to the field of vanadium and chromium separation, and particularly discloses a sodium vanadium solution treatment method which comprises the following steps: S100, adding an alkaline reducing agent into a sodium vanadium solution, and carrying out reduction of hexavalent chromium and selective precipitation reaction of trivalent chromium; s200, at the later stage of the reaction in the step S100, urea is added into a solution system, and a deep removal reaction of silicon and chromium is carried out; and S300, after the reaction in the step S200 is finished, solid-liquid separation is conducted, silicon-chromium slag and purified vanadium liquid are obtained, silicon-chromium oxide is obtained after the silicon-chromium slag is treated and can be used for smelting silicon-chromium alloy, and the purified vanadium liquid is subsequently used for preparing a high-purity vanadium oxide product. According to the method, the vanadium sodium salt solution obtained through a vanadium slag sodium salt roasting-water leaching process is used as a raw material, hexavalent chromium in the solution is reduced through an alkaline reducing agent, selective precipitation separation of hexavalent chromium and vanadium is achieved, and meanwhile urea is supplemented to conduct synergistic precipitation removal on silicon in the solution.
Owner:PANZHIHUA IRON & STEEL RES INST OF PANGANG GROUP
Trailer part surface coating treatment process
The invention is applicable to the technical field of trailer part treatment, and provides a trailer part surface coating treatment process which comprises the following steps: performing high-frequency induction quenching on a trailer ball base body; a copper bottom layer is electroplated on the trailer ball base body, and a bright nickel layer is electroplated on the copper layer; a microcrack nickel layer is electroplated on the bright nickel layer, and a trivalent chromium layer is electroplated on the microcrack nickel layer through a trivalent chromium plating solution; the trailer ball base body electroplated with the trivalent chromium layer is subjected to nanometer hole sealing treatment; applying a layer of polysiloxane or UV (ultraviolet) curing type super-hard transparent finish paint on the surface subjected to hole sealing treatment in a spraying manner; a layer of micro-crack nickel is electroplated on the bright nickel layer, and a micro-crack network of the micro-crack nickel provides a preset and uniform stress release channel for a subsequent chromium layer, so that the internal stress of the chromium layer is dispersed, the brittleness of the chromium layer is greatly reduced, and the impact resistance of the chromium layer is remarkably improved; and a trivalent chromium chromium plating process is adopted to replace traditional hexavalent chromium chromium plating, so that the environmental pollution and toxicity are greatly reduced, and the requirements of modern environmental protection regulations are better met.
Owner:HANQIAO HUZHOU HARDWARE PROD
Method for treating vanadium extraction wastewater by using organic amine flue gas desulfurization slag
PendingCN121159012AWaste water treatment from metallurgical processMultistage water/sewage treatmentAmmoniacal nitrogenO-Phosphoric Acid
The invention belongs to the technical field of solid waste recycling and wastewater treatment, and particularly relates to a method for treating chromium-containing wastewater by adopting organic amine flue gas desulfurization residues. According to the method, organic amine flue gas desulfurization residues are used as a reducing agent, phosphoric acid is used for controlling the pH value of wastewater, hexavalent chromium is reduced into trivalent chromium under the acidic condition, meanwhile, desulfurization ash is converted into a melamine phosphate flame-retardant material, and trivalent chromium is separated from water in a precipitation form under the neutral condition; after the precipitate is roasted, chromium sesquioxide powder with relatively high purity is obtained, residual ammonia nitrogen in the wastewater, the added magnesium salt and residual phosphoric acid in the water form struvite precipitate, so that the ammonia nitrogen in the water is removed, and the struvite can be used as a raw material of a slow-release fertilizer. According to the method, the treatment cost of the vanadium extraction wastewater and the flue gas desulfurization slag is remarkably reduced, valuable elements are fully recycled, and resource utilization of flue gas desulfurization waste in a waste-to-waste mode is achieved.
Owner:SHENYANG UNIV
Environment-friendly corrosion-resistant metal material coating and preparation method thereof
The invention discloses an environment-friendly corrosion-resistant metal material coating and a preparation method thereof. According to the invention, the waterborne polyurethane resin is adopted as a matrix, and the modified chitosan, the sodium molybdate phytic acid compound and other biological bases and a chromium-free corrosion inhibition system are combined, so that the use of benzene solvents, hexavalent chromium and other toxic substances in the traditional paint is avoided from the source. Through construction of a graphene oxide composite titanium dioxide heterojunction, the coating triggers a photocatalytic reaction under visible light, surface pollutants can be decomposed, the electron migration activity of a metal interface is reduced, and the neutral salt mist resistance time is made to break through 3000 hours and is increased by three times or above compared with a conventional epoxy coating. A dual intelligent response mechanism formed by the matrine microcapsules and the modified chitosan can quickly release corrosion inhibition factors and dynamically repair microcracks at the initial stage of corrosion, so that stable protection of the coating in a corrosion medium with a wide pH range of 2-12 is realized, and the service life of a metal substrate in extreme environments such as ocean and chemical engineering is remarkably prolonged.
Owner:NANTONG INST OF TECH
Electroplating chromium-containing wastewater treatment device and electroplating chromium-containing wastewater treatment method
InactiveCN120229850AWater contaminantsSludge treatment by pyrolysisMetallurgyElectroplating wastewater
The invention discloses an electroplating chromium-containing wastewater treatment device and an electroplating chromium-containing wastewater treatment method, and belongs to the technical field of electroplating wastewater treatment. The electroplating chromium-containing wastewater to be treated flows into a cathode chamber in a reaction treatment unit from a water inlet, hexavalent chromium in the electroplating chromium-containing wastewater is converted into trivalent chromium through electrons near a carbon-based cathode, and then the trivalent chromium flows into an anode chamber in the reaction treatment unit; the dissolving-out type iron anode loses electrons to generate ferrous ions, residual hexavalent chromium in the electroplating chromium-containing wastewater is reduced into trivalent chromium through the ferrous ions, and the wastewater sequentially passing through the cathode chamber and the anode chamber flows out of the water outlet; wherein electron movement is generated between the cathode chamber and the anode chamber through the conductive diaphragm, so that an electrode and a medicine do not need to be additionally added when the device is used for treating the wastewater, and the wastewater treatment cost is reduced.
Owner:ZHEJIANG RUNWU ENVIRONMENTAL TECHNOLOGY CO LTD +1
Method for preparing ceramsite from hazardous waste chromium-containing sludge and secondary aluminum ash and product thereof
The invention discloses a method for preparing ceramsite by utilizing hazardous waste chromium-containing sludge and secondary aluminum ash and a product thereof, and the method comprises the following steps: uniformly mixing fine-grain chromium-containing sludge, secondary aluminum ash and dolomite mineral powder, roasting, cooling, grinding and uniformly mixing with kyanite slime, adding water, stirring, granulating and drying to obtain the ceramsite. Raw material balls are obtained; sintering under an air atmosphere condition, and cooling to obtain the ceramsite. According to the method disclosed by the invention, through a method of combining roasting, grinding, hydration and sintering, on one hand, collaborative resource treatment of hazardous wastes including the chromium-containing sludge and the secondary aluminum ash and common solid wastes including kyanite slime and dolomite mineral powder is realized, and low-carbon transformation of the chromium-containing sludge and the secondary aluminum ash from hazardous waste landfill to building material recycling is realized; besides, the lowest leaching concentration of hexavalent chromium of the obtained ceramsite is 0.16 + / -0.01 mg / L, and the ceramsite has the advantages of no dangerous characteristic, high strength and double advantages of deep detoxification of pollutants and improvement of material performance.
Owner:CHANGSHU INSTITUTE OF TECHNOLOGY
Step-by-step leaching remediation method for chromium-contaminated soil
The invention provides a step-by-step leaching remediation method for chromium-contaminated soil, which comprises the following steps: mixing the chromium-contaminated soil and a first leacheate, carrying out first oscillation, then adding a second leacheate into the mixture, and carrying out second oscillation to obtain the remediated soil, the first leacheate comprises sodium salt; the second leacheate comprises organic acid and ferric salt; the temperature of the second oscillation is 70 DEG C to 90 DEG C. The method comprises the following steps: desorbing and releasing hexavalent chromium adsorbed on the surfaces of soil particles by using a sodium salt eluting agent, dissolving the soil particles to promote release of insoluble hexavalent chromium, and dissolving the soil particles containing high-concentration insoluble hexavalent chromium by using a composite eluting agent of organic acid and ferric salt under a high-temperature condition. And when the hexavalent chromium is released, the hexavalent chromium is efficiently reduced and stabilized, so that the aim of removing the hexavalent chromium in the polluted soil is fulfilled.
Owner:CHONGQING UNIV
Photocatalytic material as well as preparation method and application thereof
PendingCN121513912AWater treatment compoundsWater/sewage treatment by irradiationHydration reactionArginine
The invention relates to the technical field of sewage treatment, and discloses a photocatalytic material and a preparation method and application thereof.The method comprises the following steps that bismuth nitrate pentahydrate and sodium bromide are added into a mannitol solution according to the molar ratio of 1: 1.5, and ultrasonic dispersion is conducted to form turbid liquid; adding arginine into the turbid liquid, wherein the molar ratio of the arginine to the bismuth nitrate pentahydrate is (0-2.5): 1; adjusting the pH value of the turbid liquid and stirring to obtain a precipitate; the precipitate is filtered, washed and dried, and the photocatalytic material nVBi-(110) BiOBr is obtained.By means of the photocatalytic material, the removal rate of hexavalent chromium in alkaline wastewater with the pH being 7-10 can still exceed 90% within a short time, the photocatalytic material shows excellent stability and reaction activity, the technical problem that hexavalent chromium is difficult to remove efficiently in the alkaline environment is successfully solved, and the photocatalytic material has good application prospects. The method has important environmental application value and popularization potential.
Owner:NORTHEAST INST OF GEOGRAPHY & AGRIECOLOGY C A S
A Remediation Agent and Remediation Method for Chromium(VI)-Contaminated Soil
The present application provides a remediating agent and a remediation method for hexavalent chromium contaminated soil, which relates to the field of treatment and remediation of contaminated soil. Based on 100% by mass, the raw materials of the remediating agent for hexavalent chromium contaminated soil include: 25%-40% of photoinitiator, 5%-10% of organic acid, and 50%-65% of water; the photoinitiator includes polyethylene glycol. The remediating agent for hexavalent chromium contaminated soil can in-situ reduce hexavalent chromium in the soil to trivalent chromium. The organic acid can reduce the soil pH value, alleviate soil salt damage, improve the soil environment, and promote crop growth; polyethylene glycol and the organic acid can also act as stabilizers to prevent trivalent chromium in the soil from being oxidized to hexavalent chromium. Using this remediating agent to treat chromium contaminated soil has simple equipment requirements, is easy to use, has low costs, high remediation efficiency, low operating costs, does not produce secondary pollution, and has broad prospects for popularization and application.
Owner:BEIJING MINING & METALLURGICAL TECH GRP CO LTD