315 results about "Chromic salt" patented technology

This invention relates to a preparation method that prepares chromic oxide powder by using water heat to deoxidize chromate. Use chromate water solution as raw material, CO2 as acidifying agent, process by surface active agent, directly deoxidize at condition of heat water, get hydrated Cr2O3 slurry, centrifugalize, separate, dry, calcinate hydrated Cr2O3 at different temperature, prepare globular Cr2O3 micropowder. Its grade size is between submicron and nanometer. This invention utilizes surface active agent to control sexavalent chromic salt which can be directly deoxidized to get trivalence chrome crystal. It can control hydrated chromic oxide calcinating temperature to prepare globular Cr2O3 micropowder of which grade size can be controlled.

The invention relates to a lithium anode material doped with phosphate ferrous iron, and relative preparation. Wherein, the product has common advantages of lithium battery, while its discharge capacity can reach 150mAh/g, the 500-circled capacity is over 90%, with low cost. The invention is characterized in that: its formula is LiFe0.99M0.01PO4/C; M is Cr, Zn, and Ca; the preparation comprises that (1) mixing and grinding lithium carbonate, ferrous salt, chromate salt, zinc salt, calcium salt, phosphorus source and glucose; (2), preheating the powder material in step (1) in inertia gas and low temperature; (3), grinding the material in step (2), under inertia gas, to be burnt, cooled and screened at 300-deal screen. The invention can be used in the anode of lithium battery.

A trivalent chromic ion iridescent passivating agent for galvanizing and its preparing method are disclosed. It consists of trivalent chromic salt, chelating agent, oxidant, the mol ration is 1:1:2.5-1:2:5.5, the trivalent chromic ion concentration in passivating groove liquid is 2.5-25g/L. It is prepared by adding the components into reactor, heating, mixing and chelating reacting, boiling and back-flowing to remove nitrogen dioxide after reacting, adding water and adjusting to obtain passivating agent concentrate with Cr3+ ionic concentration 30-80g/l after discharging. It achieves no pollution and wide range.

The invention belongs to the field of a method for producing chromic salt, in particular relates to a method for producing and cleaning potassium chromate. The method comprises the steps that chromite is reacted with oxidant with a chemical dose inside KOH-KNO3-H2O medium to obtain a mixed resultant of reaction containing alkali liquor, potassium chromate and slag after reaction, wherein the mass ratio of KOH and chromite is 1:1 to 2:1, and the mass ratio of KNO3 and chromite is 0.5:1 to 2:1. Through the leaching of the mixed resultant of reaction, the phases of potassium chromate macrocrystal-alkali liquor containing potassium nitrate-slag are separated, foreign matters in the solution are removed, the mixture is evaporated and crystallized, the obtained potassium chromate crystal is eluted and the pure product of potassium chromate is obtained. The percent conversion of chromium is higher than 99 percent and the rate of containing chromium in slag is less than 0.2 percent.

The invention discloses a method of preparing aluminum or aluminum alloy trivalent chromium chemical conversion film, comprising: aluminum or aluminum alloy work pieces are activated for 1 to 2 minutes in sodium hydroxide solution with a concentration of 50g/L to 100g/L and activation reaction temperature is 5 deg C to 30 deg C; using deionized water to wash the work pieces; putting the washed work pieces into mixed aqueous solution of soluble chromic salt and phosphoric acid to make a chromaking for 6 to 10 minutes, wherein, chromium ion has a concentration of 1g/L to 20g/L, and the phosphoric acid has a concentration of 1g/L to 25g/L; using dilute sodium hydroxide or dilute sulfuric acid to adjust reaction system PH value to 1.6 to 4.0 and the chromaking temperature to 10 deg C to 60 deg C. The invention solves a shortcoming that in existing technology hexavalent chromium has great toxicity. Technological process and products of the invention reach environmental requirements. The produced trivalent chromium chemical conversion film has the same quality with hexavalent chromium chemical conversion.

The clear production method for Cr-free vehicle seat cushion comprises: hair-saving, combing acid and base for expansion; ammonia-free deliming, dipping weak acid and low slat, Cr-free bating, composite batting, and adding strong-absorption fat for dyeing to treat skin from pig, cattle or sheep. The product has shrinkage temperature up to 110Deg, shows well hand feeling and resistance to thermal and age. This invention reduces material quantity and 30-50% sewage discharge, improves absorption rate, and brings a new way for Cr-free leather.

The invention discloses a method for preparing a nano-size catalyst of copper chromite and copper ferrite, and belongs to the technical field of nano-size catalyst preparation. The method of the invention comprises a sol-gel process and a vacuum freezing drying (VFD) process. Firstly, a mixed solution is prepared from a soluble copper salt and a soluble chromium salt or iron salt, added with a surface active agent, and mixed uniformly, and then the system is added with a precipitating agent to carry out precipitation reaction under the condition that the pH value is between 6.8 and 9.5, then is kept stand, aged, washed and melted in a water bath for 2 to 8 hours at a temperature of between 70 and 95 DEG C, thus sol is obtained; then the sol is subjected to freezing drying in a vacuum freezing dryer to obtain dried gel which is a precursor of the catalyst; finally, the dried gel is roasted to obtain the nano-size catalyst of copper chromite (CuCr2O4) or copper ferrite (CuFe2O4). The catalyst prepared by the method has the advantages of high purity, small grain diameter, good dispersivity, high catalytic activity, and the like.

Provided is a process for treating Cr6+ in waste water, which comprises: adding nano magnetite of montmorillonite substrate in waste water containing hexavalent chromium, stirring for 5 minutes to 2 hours at normal temperature and then placing for 15 minutes to 2 hours, employing magnet or additional magnetic field to recycle adsorption materials. The process for preparation by employing the nano magnetite of montmorillonite substrate comprises that mixing ferric salt and ferrous iron salt solution, adding by ammonia spirit, adding by hydrochloric acid after filtering, rinsing and solid-liquid separation treatment, adding by montmorillonite then solid-liquid separating, drying and dewatering and the like. The invention of treating waste water containing Cr6+ has the advantages of high efficiency, low cost, simple operation and the like, and can be widely used for waste water treatment in a plurality of fields, such as tanning, plating, metallurgy, pharmacy, ferrochrome smelting, pigment, chromic salt chemical industry and the like.

The invention provides a conductive anode oxidation technology of aluminum and alloy parts thereof, which comprises the following steps: (a) alkaline corrosion: the aluminum and the alloy parts are put into an alkaline solution for removing an oxide skin generated in natural state; (b) bright dipping: the aluminum and the alloy parts are put into 40 to 70 percent nitric acid solution for removing the dust so as to lead the aluminum and the alloy parts to expose metal luster; (c) anode oxidation: the aluminum and the alloy parts are put into a mixed electrolytic solution prepared by chromic salts and villaumite, 10 to 35V of voltage and 0.5 to 5A/dm<2> anodic current density are exerted to the solution at normal temperature, and the time for anode oxidation is 5 to 30min; and (e) drying. A film layer presents slightly transparent rainbow color and is bright, and has smooth and compact appearance. The technology has excellent welding performance, good electric conductivity and better antirust property, and solves the contradiction between the aluminum and the alloy parts, and the electric conductivity and the welding performance.

The invention discloses a pre-treating agent for surfaces of an aluminum profile and an aluminum alloy profile. The pre-treating agent comprises the following constituents by mass: 35-45 percent of water-solubility chromic salt, 0.1-3 percent of alkali metal zirconate, 0.1-2 percent of sodium salicylate, 5-10 percent of water-solubility coalescing agents, and 5-10 percent of wetting agents with the balance being water. The pre-treating agent for the surfaces of the aluminum profile and the aluminum alloy profile does not contain hexavalent chromium, and therefore environmental pollution is avoided, the pre-treating agent is stable in property and long in using period, a layer of transparent or light colored corrosion-resisting conversion coating can be formed on the surface of an aluminum profile workpiece, and a treated aluminum profile still maintains original metal characteristics. The conversion coating has extremely good corrosion-resistant performance and is firm in bonding, and the bonding force between the workpiece and the conversion coating and between the workpiece and paint can be notably increased. Besides, the using temperature range of the pre-treating agent is from the room temperature to 100 DEG C, the pre-treating agent can turn into a membrane quickly at the room temperature, and the effect is optimal when the pre-treating agent is heated to 20-50 DEG C.

The invention provides a wave-transmission and thermal-insulation material with high-temperature radiation resistance and a preparation method of the material. Specifically, the method comprises steps as follows: chromic salt is diluted and dissolved, an alkaline reagent is added, and a chromium salt complex solution is obtained; wave-transmission fiber reinforcement is soaked with the chromium salt complex solution, treated with sol-gel and dried, and a fiber preform is obtained; the fiber preform is sintered, and a chromium (III) oxide composited fiber reinforcement matrix is obtained; the fiber reinforcement matrix is soaked with silicon dioxide sol, treated with sol-gel, subjected to aging and solvent replacement and dried, and a fiber reinforced aerogel composite material is obtained; the fiber reinforced aerogel composite material is subjected to dampproof treatment, and the wave-transmission and thermal-insulation material with high-temperature radiation resistance is obtained. The invention further provides the wave-transmission and thermal-insulation material with high-temperature radiation resistance and an application of the material. According to the method, grain size and crystal form of chromium (III) oxide can be controlled, and excellent high-temperature radiation resistance and dielectric property of the material are guaranteed.

The invention discloses high-corrosion-resistance trivalent chromium blue white passivation concentrated solution. The passivation solution comprises the following raw materials and contents: 100-350 g/L of chromic salt, 50-250 g/L of cobalt salt, 50-200 g/L of complexing agent, 50-200 g/L of oxidizing agent, and 10-120 g/L of pH conditioning agent; and solvent is water. The passivation concentrated solution adopts the most advanced international trivalent chromium, contains no hexavalent chromium, belongs to the new generation of environment-friendly product, and is simple in process operation, easy to operate and control, excellent in stability, uniform and bright in blue of a passivation membrane, compact and firm in film formation, higher in corrosion and collision resistance and meanwhile, longer in service life.

The invention relates to a method for electrolyzing and recovering hexavalent chromium in chromium-electroplating waste water. Aiming at overcoming defects that chromium recovered from chromium waste water by the prior chromium-electroplating waste water treatment method cannot be reused for an electroplating tank, the invention provides the method for electrolyzing and recovering the hexavalent chromium in the chromium-electroplating waste water, which has simple operation and low recovering cost. The method comprises the following steps: sulfuric acid solution, sodium metabisulfite and sodium carbonate solution are sequentially added to the chromium-electroplating waste water; the reacted chromium-electroplating waste water flows into a precipitator for precipitation; through the precipitation, supernatant fluid flows into a neutralization pond for neutralization, the chromium-electroplating waste water is input a press filter for press filtering, and obtained chromic salts are washed with clear water; the chromium-electroplating waste water, the chromic salts and sulphuric acid are added in an electrolytic tank of a concentration purifier, and the sulphuric acid is added in a porous pot of the concentration purifier; when the concentration of the hexavalent chromium is larger than 20g/l and the concentration of trivalent chromium is smaller than 1g/l by electrolysis in the chromium-electroplating waste water in the electrolytic tank of the concentration purifier, the chromium-electroplating waste water can be used as a replenishing liquor for the electroplating chromium.

The invention discloses trivalent chromium electroplate liquid capable of forming a black clad layer. Each liter of the trivalent chromium electroplate liquid comprises the following raw materials: a cylinder opening agent, 20 to 150g of stabilizing agent, 10 to 20g of cobalt chloride or manganese chloride, 0.6 to 1.5g of ferric chloride, and 1 to 10g of wetting agent, wherein each liter of cylinder opening agent consists of 5 to 30g of blackening agent, 90 to 140g of chromic salt, 180 to 300g of L conducting salt, 25 to 90g of pH buffering agent. The trivalent chromium electroplate liquid capable of forming the black clad layer has simple components and is easy to maintain; and the formed black clad layer has deep black color and high adhesion.

The invention discloses a method for synthesizing an MIL-101 chrome metal organic framework by nitrogen heterocyclic. The method comprises the following steps of: using the nitrogen heterocyclic as an additive; adding the additive to water; stirring the additive and the water; and then adding an organic ligand terephthalic acid to the water; stirring the organic ligand terephthalic acid and the water; and finally adding a water soluble metal chromic salt to the water; and stirring the water until the metal chromic salt is dissolved; transferring an obtained mixture into a stainless steel high pressure reaction kettle with a polytetrafluoroethylene lining or a high pressure stirring reaction kettle with a polytetrafluoroethylene lining; crystallizing the mixture at a constant temperature 150 DEG C for 34 hours so as to obtain a product, wherein the yield of the MIL-101 chrome metal organic framework material is 60-90%. The method for synthesizing the MIL-101 chrome metal organic framework by the nitrogen heterocyclic, disclosed by the invention, has the advantages of low synthesis temperature, high purity and high yield.

The preparation method of spherical Cr2O3 high-purity ultrafine powder body by using liquid phase method which can control grain size. It uses Na2Cr2O7 as raw material and adopts the processes of acidity reduction, surfactant treatment, pH value regulation, using composite precipitant to control precipitation, solid-liquor separation and roacting to obtain the fresh green spherical Cr2O3 ultrafine powder body with different grain size ranges, and its grain size can be controlled in the range of submicrometer and nanometer range according to the requirements. Said invention also provides a simple method for controlling its granule form and granule size, and said product has extensive application in functional coating material, special product special-purpose additive or special field special-purpose material field.

The invention relates to a trivalent chromium natural colour passivation solution for processing an aluminium alloy, comprising the following components by contents: 1-2 g/L of chromic salt, 0.05-0.1 g/L of zirconium salt, 0.01-0.03 g/L of nickel sulfate NiSO4.6H2O, 0.4-0.8 g/L of film-forming agents, 0.4-0.6 g/L of trisodium citrate Na3C6H5O7.2H2O, and the balance of water. The trivalent chromium natural colour passivation solution does not contain harmful substances, i.e. hexavalent chromium, lead, mercury, cadmium, polybrominated diphenyl ethers, polybrominated biphenyl, and the like, can be recycled, realize the clean production, passivate at normal temperature and save the energy; in addition, the aluminium alloy processed by the trivalent chromium natural-colour passivation solution has white and bright surface colour and lustre, colour approximate to the natural colour of the aluminium alloy and film neutral salt spray corrosion property meeting the national standard and can realize the substitution of the trivalent chromium passivation solution for a hexavalent chromium passivation solution.

The invention relates to a method for synthesizing 2-methyl-1, 4-naphthoquinone through taking 2-methylnaphthalene as a raw material, which comprises the following steps of: taking the 2-methylnaphthalene as the raw material, taking glacial acetic acid as a solvent, taking hydrogen peroxide as an oxidizing agent and catalyzing with a catalyst to synthesize the 2-methyl-1, 4-naphthoquinone. The reaction temperature is 20-80 DEG C, and the dripping rate is 0.02-1 mL/min. After the end of dripping, the temperature is preserved for 0.5-4 hours. After the reaction is ended, and feed liquid is concentrated to 1/2-1/6 of the original volume, the feed liquid is poured into ice water with the volume being 3-6 times that of the feed liquid and is then stewed, filtered and dried to obtain the 2-methyl-1, 4-naphthoquinone. The method has the beneficial effects that a mixed acid catalytic system is used; compared with a traditional chromate oxidation method, the method has the advantages of good selectivity and high yield; and the pollution to a large quantity of chromium metal ions generated in the traditional industrial production can be avoided, and therefore, the industrial application value is higher.

The invention belongs to the field of metallic materials and relates to a chemical conversion solution and a treatment method for the surface of a die-casting aluminum alloy. The conversion solution is formed by compounding an A ingredient and a B ingredient, the A ingredient consists of a zirconium salt, a surfactant and a trivalent chromium salt; the B ingredient consists of a complexing agent and a film-forming accelerant; in the A ingredient, the content of the zirconium salt is 5-60 g/L, the content of the surfactant is 2-10 g/L, and the content of the trivalent chromium salt is 5-50 g/L; in the B ingredient, the content of the complexing agent is 4-20 g/L, and the content of the film-forming accelerant is 2-15 g/L; and the method comprises the pretreatment on the surface of the die-casting aluminum alloy and the zirconium salt chemical conversion treatment. A chemical conversion coating contains zirconium phosphate compounds and a small amount of trivalent chromium compounds, wherein the coating has uniform light blue and the thickness of about 0.5-1 micron. The zirconium salt chemical conversion coating prepared by the method has excellent corrosion resistance, the bonding strength between the coating and a substrate is high, the product, the waste water and the waste liquor obtained after the chemical conversion treatment do not contain hexavalent chrome which is harmful to the environment and the health of human bodies.

The invention relates to a process for preparing compound of nano magnetite and diatomite capable of removing hexavalent chromium (Cr6+) from water, which comprise: proportionally mixing ferric salt and ferrous salt aqueous solutions with the same concentration of 0.02-0.5mol/L at room temperature, adding by diatomite powder and uniformly stirring, heating and stirring to slowly add ammonium hydroxide solution, then, stopping adding till the pH value of suspension reaching 8-9, solid-liquid separating and rinsing; vacuum grinding and disintegrating. The invention employed to treat hexavalent chromium in the waste water has the advantages of low cost, high efficiency, simple operation, easy recovery and the like, and can be widely used for waste water treatment in fields of plating, tanning, metallurgy, pigment, chromic salt chemical industry and the like.

The invention relates to a chromium zinc selenium fertilizer, which comprises the following components by weight: 10-20 of selenate or selenite, 35-50 of a chromic salt, 25-35 parts of zinc sulfate, 10-15 of boric acid or borax, 2-5 of sodium nitrophenolate, and 2-5 of citric acid. The production process of the fertilizer consists of: material preparation, burdening, stirring, crushing, inspection, and packaging. And the using method includes: use for plants: dissolving the chromium zinc selenium fertilizer in water, and spraying the solution on the front and reverse side of a leaf as well ason a fruit with a spraying amount that generates no droplet but sprays plants wet; use for livestock and laying hens: blending the chromium zinc selenium fertilizer uniformly in feed for continuous use. The chromium zinc selenium fertilizer of the invention fills the domestic gap of chromium zinc selenium fertilizers, substantially increases the content of selenium, zinc, and chromium of agricultural products, and improves quality. It can also significantly improve the disease-resistant ability of crops. The using technology of the invention is fully mature, and has very strong paleogenesis, stability, and operability.

The invention relates to a preparation method of a chromium-free tanning agent, comprising the following steps: adding a hydrophilic group containing active compound and deionized water into a four-necked flask, neutralizing with sodium hydroxide, continuously stirring till dissolution, putting into an ice bath, adding cyanuric chloride, and regulating the pH value of the system with a solution of an acid binding agent to obtain a mixture A; heating the mixture A, dropwise adding p-hydroxy benzaldehyde dissolved in acetone while stirring, regulating the pH value of the system with the solution of the acid binding agent, and continuing the reaction after the materials are added; heating the system, dropwise adding p-hydroxy benzaldehyde dissolved in acetone, regulating the pH value of the system with the solution of the acid binding agent, continuing the reaction after the materials are added, cooling and discharging to obtain a mixture B; and filtering the mixture B, carrying out vacuum drying on the filter cake to obtain solid C, grinding and pulverizing the solid C to obtain the white powdered form chromium-free tanning agent. The chromium-free tanning agent can eliminate pollution from chromic salt, aluminum salt and formaldehyde and can be well absorbed, and the tanned crust leather has a white fine grain surface and is easy to be dyed into light-colored leather.

The invention discloses a chromium slag pyrolysis treatment method capable of realizing high efficiency chromium slag treatment, and reducing emission amount of harmful substances such as tar at the same time. According to the chromium slag pyrolysis treatment method, chromium slag and straw are mixed and reacted at a high-temperature area; obtained high-temperature tar gas flows to a low-temperature area, a part of the high-temperature tar gas is cooled onto the surface of the chromium slag which is delivered to the high-temperature area, and is reacted with Cr (VI) on chromium slag surface, and the other part of the high-temperature tar gas is removed via reaction with oxygen at the low-temperature area; at the same time, because of full utilization of the tar gas, effective reduction of Cr (VI) in the chromium slag is realized, and oxidation of chromium is controlled effectively; and in addition, another by-product of the chromium slag pyrolysis treatment method, high temperature tail gas is taken as a heat source to heat the chromium slag, so that energy consumption is reduced greatly.

The invention discloses a catalyst for generating high-value olefins (propylene, butylenes and isobutylene) from liquefied petroleum gas. The catalyst is characterized by comprising the following components: kaolin, garma-Al2O3, one or more chromic oxides, one or more rare earth oxides, one or more alkaline earth metal oxides and silicon oxide or silicate, wherein the kaolin accounts for 0 to 50 percent, the garma-Al2O3 accounts for 20 to 95 percent, the chromic oxide accounts for 1 to 40 percent, the rare earth oxide accounts for 0 to 20 percent, the alkaline earth metal accounts for 0 to 10percent and the silicon oxide or silicate accounts for 1 to 10 percent. A preparation method of the catalyst comprises the following steps of: pulping the kaolin and boehmite by adding water and stirring for 0 to 2 hours; adding active ingredients, such as a chromic salt, a rare earth metal, an alkali salt and the like into the pulp and stirring for 0 to 2 hours; adjusting the pH value of the mixture to between 1 and 3 with concentrated nitric acid; adding a silicate and an alumina sol into the mixture; spraying and drying the mixture; and roasting the mixture at the temperature of between 450 and 650 DEG C for 0 to 5 hours in a nitrogen atmosphere and roasting the mixture at the temperature of between 380 and 800 DEG C for 0 to 20 hours in air atmosphere to obtain the catalyst in a fluidized bed reactor, wherein the reaction conditions comprise that: the temperature is 500 to 700 DEG C, the absolute pressure is 0.01 to 0.2Mpa and the volume space velocity is 300 to 2,000 per hour, and the liquefied petroleum gas can be the liquefied gas for resident fuel from a catalytic cracker in a refinery and also can be one of or a mixture of propane, butane and isobutene.