52 results about "Iron oxalate" patented technology

The invention relates to a method for separating and recovering iron from red mud. The method is characterized by comprising the steps: of leaching out and removing iron from the red mud by using an oxalic acid solution, and filtering to obtain iron-free red mud and an iron oxalate-containing leaching solution, wherein the obtained iron-free red mud can be used as a raw material for producing cement and fireproof bricks; iron oxalate in the obtained leaching solution is reduced to ferrous oxalate through membrane electrolysis or adding a reducing agent and ferrous oxalate is precipitated out, or iron in the solution is separated by directly neutralizing and precipitating an iron hydroxide and oxalate mixture; obtained ferrous oxalate is decomposed to obtain oxalic acid and an iron-containing compound; the obtained iron hydroxide and oxalate mixture is selectively leached out, separated and recovered to obtain oxalic acid and an iron-containing compound; the process of returning recovered oxalic acid to the red mud to leach out and remove iron is cyclically used. The method has the characteristics of short technological process, good iron separation effect, simplicity and convenience in operation, environmental friendliness and the like, and is suitable for large-scale industrialized application.

The invention relates to a carbon coated lithium iron phosphate microwave-synthesizing method, relating to the preparation of anode material of a Li-ion battery. The invention weighs lithium carbonate, iron oxalate and ammonium diacid phosphate, proper amount of heat conduction agent and organic matter in chemical gauging ratio, using anhydrous alcohol as dispersant to fully grind and mix them, drying and pressing the mixture into blocks, placing the blocks in a pot holding activated carbon, and placing the pot in microwave field for irradiative heating so as to be able to make uniform- phase carbon coated lithium iron phosphate. The invention can realize carbon coating of lithium iron phosphate and more rapidly and uniformly heat the raw materials, beneficial to uniform and rapid reaction of massive raw materials. The method can shorten production cycle and reduce energy consumption.

Methods for improving surface roughness of an environmental barrier coating including providing a component having a plasma sprayed environmental barrier coating; applying a slurry to the environmental barrier coating of the component, the slurry being a transition layer slurry or an outer layer slurry; drying the environmental barrier coating having the applied slurry; and sintering the component to produce a component having an improved surface roughness where the slurry includes a solvent; a primary transition material, or a primary outer material; and a slurry sintering aid selected from iron oxide, gallium oxide, aluminum oxide, nickel oxide, titanium oxide, boron oxide, alkaline earth oxides, carbonyl iron, iron metal, aluminum metal, boron, nickel metal, iron hydroxide, gallium hydroxide, aluminum hydroxide, nickel hydroxide, titanium hydroxide, alkaline earth hydroxides, iron carbonate, gallium carbonate, aluminum carbonate, nickel carbonate, boron carbonate, alkaline earth carbonates, iron oxalate, gallium oxalate, aluminum oxalate, nickel oxalate, titanium oxalate, solvent soluble iron salts, solvent soluble gallium salts, solvent soluble aluminum salts, solvent soluble nickel salts, solvent titanium salts, solvent soluble boron salts, and solvent soluble alkaline earth salts.

A polishing composition for a memory hard disk, which comprises the following components (a) to (d):(a) from 0.1 to 50 wt %, based on the total amount of the polishing composition, of at least one abrasive selected from the group consisting of silicon dioxide, aluminum oxide, cerium oxide, zirconium oxide, titanium oxide, silicon nitride and manganese dioxide,(b) from 0.001 to 10 wt %, based on the total amount of the polishing composition, of at least one iron salt selected from the group consisting of iron nitrate, iron sulfate, ammonium iron sulfate, iron perchlorate, iron chloride, iron citrate, ammonium iron titrate, iron oxalate, ammonium iron oxalate and an iron chelate complex salt of ethylenediaminetetraacetic acid,(c) from 0.01 to 30 wt %, based on the total amount of the polishing composition, of at least one peroxydisulfate salt selected from the group consisting of ammonium peroxydisulfate, potassium peroxydisulfate and sodium peroxydisulfate, and(d) water.

The invention discloses a gradient-doped manganese iron oxalate precursor and a preparation method thereof. The chemical structural formula of the gradient-doped manganese iron oxalate precursor is Fe1-x-yMnx{M}yC2O4.2H2O, M is a doped element, the concentration of M outwardly increases from the center along the radium in a gradient manner, x is not lower than 0.4 and not greater than 0.9, and y is not lower than 0.02% and not greater than 5%. Gradient doping in a bulk phase in the invention realizes uniform mixing of iron and manganese atoms, and the concentration increasing gradient distribution of the doped element M from the core to the shell improves the ion conductivity, the electron conductivity, the cycle performances and the rate performance of the above material, and a new approach is provided for the large scale application of lithium manganese iron phosphate.

The present invention discloses a method for preparing ferrous oxalate, which belongs to the technical field of powdered material preparation. The aim of the invention is to provide a preparation method of ferrous oxalate which is high in purity, controllable in granularity, even in grain size, and high in conductivity. The method comprises the following steps of locating ferrous sulfate into dilute sulphuric acid, adding scrap iron with stirring, and obtaining a ferrous sulfate solution after suction filtration; dissolving oxalic acid or/and ammonium oxalate in distilled water with stirring and heating, and obtaining a mixed solution of oxalic acid or/and ammonium oxalate through suction filtration after dissolution; and, slowly adding the ferrous sulfate solution into oxalic acid solution, keeping the temperature, stirring, separating ferrous sulfate from the original synthetic solution after keeping stand, and obtaining ferrous oxalate powder through washing and drying. The ferrous oxalate prepared by the preparation method is a powder with a medium grain diameter of between 0.5 and 80 mu m. The granularity is completely controllable. The product purity is greater than 99.0 percent. The conductivity is high. The electrochemical performance of the ferrous phosphate salt composite material is largely improved. The conductivity of lithium iron phosphate is improved by 5 orders of magnitude.

The invention provides a preparation method of nickel ferrite based magnetic loaded type titanium dioxide photo-catalyst with micron grade micron order as carrier; the preparation process includes the following steps: adding green copperas solution and oxalic acid solution into the nickel salt solution for reaction to obtain the mixture precipitate of oxalate of nickel oxalate and iron oxalate; then baking to obtain the micron grade nickel ferrite powder; adding the titanic sulfate solution into the suspension of micron grade nickel ferrite powder so as to crystallize the titanium ions on the suspended particulates in the suspension to form a wrapping layer and obtain the nickel ferrite based magnetic loaded type titanium dioxide photo-catalyst product. The magnetic loaded type titanium dioxide photo-catalyst prepared by the method of the invention has good dispersibility; and the particle diameter of the particles is about 5 mum; the titanium dioxide is obviously wrapping on the surface of the nickel ferrite to form a core/shell structure with large wrapping capacity as well as adjustable and homogenous distribution; the specific surface is 90-110 m/g; and the photo-catalyst has the feature of strong soft magnetism, can be rapidly recycled in aqueous solution and has higher catalytic activity, so that organic wastewater can be completely degraded. The preparation technology is simple, the cost is low, and large-scale production is easily realized.

The invention relates to a method for producing high-purity battery grade iron oxalate by utilizing pickle liquor, comprising the following steps: the pickle liquor is pre-treated for lowering spent acid content, thus leading the pickle liquor to generate ferrite solution with a certain concentration; then after strict filtering and magnetic separation, the ferrite solution is transported into a reaction kettle, then industry ammonia is added and the solution is stirred for reaction to generate ferrous hydroxide gelatin; the soluble oxalic acid solution is slowly added in and stirred, and then the mixture is stirred by a conversion reaction kettle and heat preservation is carried out, thus obtaining iron oxalate slurry after reaction; iron oxalate mother solution is separated in the iron oxalate slurry, and the separated iron oxalate is washed, dried and crashed for obtaining high-purity superfine iron oxalate products. The method has the beneficial effects that: the pickle liquor in industrial production is fully utilized; a two-step liquid phase method of oxidation and conversion is adopted for leading the reaction to be more fully, so that the reaction rate is greatly improved, the grain diameter of the finished products iron oxalate is fine and uniform, D50 is less than or equal to 5mum, and the content of the iron oxalate is more than or equal to 95.5 percent; furthermore, the pickle liquor is used as raw material, and cyclic utilization and environmental protection of the industrial waste are utilized, thus changing waste into valuable and greatly lowering the production cost.

The invention relates to a hard anodizing coloring method of the aluminum alloy surface, belonging to the technical field of aluminum alloy surface treatment and aiming to solve the technical problems in the prior art that the process for treating the aluminum alloy surface has complicated steps and the treated aluminum alloy surface has a single color. The hard anodizing coloring method of the aluminum alloy surface comprises the following steps: a, hard anodizing: subjecting an cleaned aluminum alloy substrate to hard anodizing at 4-13 DEG C so that the a hard anodized film is formed on the aluminum alloy surface; and b, coloring: coloring the aluminum alloy under the condition of the existence of iron oxalate, and sealing to obtained the colored aluminum alloy. The hard anodizing coloring method of the aluminum alloy surface further comprises the step of treating the aluminum alloy at the high temperature of 380-450 DEG C. The hard anodizing coloring method of the aluminum alloy surface has a short technical process and a good coloring effect and ensures that the anodized film is not easy to fall and is colorful. The aluminum alloy surface has the high hardness value (HV) 0.05 of more than 400.

The present invention has an object to remove effectively metallic contaminants adhering to the glass substrate surfaces without increasing roughness of the glass substrate surfaces in the glass substrate for a magnetic disk. In a manufacturing method of a glass substrate for a magnetic disk having a cleaning step of the glass substrate, cleaning step having a treatment of contacting the glass substrate with a cleaning liquid containing oxalate and divalent iron ions and having a pH of not less than 2 and not more than 4. The divalent iron ions are added by adding ammonium iron (II) sulfate, iron (II) sulfate and iron oxalate (II) to oxalic acid.

Methods for improving surface roughness of an environmental barrier coating involving providing a component having a plasma sprayed environmental barrier coating; applying a slurry to the environmental barrier coating of the component, the slurry being a transition layer slurry or an outer layer slurry; drying the environmental barrier coating having the applied slurry; and sintering the component to produce a component having an improved surface roughness wherein the slurry includes water; a primary transition material, or a primary outer material; and a slurry sintering aid selected from iron oxide, gallium oxide, aluminum oxide, nickel oxide, titanium oxide, boron oxide, alkaline earth oxides, carbonyl iron, iron metal, aluminum metal, boron, nickel metal, iron hydroxide, gallium hydroxide, aluminum hydroxide, nickel hydroxide, titanium hydroxide, alkaline earth hydroxides, iron carbonate, gallium carbonate, aluminum carbonate, nickel carbonate, boron carbonate, alkaline earth carbonates, iron oxalate, gallium oxalate, aluminum oxalate, nickel oxalate, titanium oxalate, water soluble iron salts, water soluble gallium salts, water soluble aluminum salts, water soluble nickel salts, water titanium salts, water soluble boron salts, and water soluble alkaline earth salts.

Polyamide-based compositions may be heat stabilized by compositions of iron oxalate and diapentaerythritol. The heat stabilized polyamides may be used for production of moulding materials which may be injection moulded, blow-moulded, or extruded to provide articles of manufacture.

The invention provides a method for recycling iron resource from soft manganese ore leaching slag. The method comprises the following steps: (1) preparing pulp with soft manganese ore slag by taking a mixed solution of an oxalic acid solution or oxalic acid and an oxalate solution as a leaching agent, so that iron in the soft manganese ore leaching slag is converted into soluble iron oxalate; (2) performing liquid-solid separation to obtain waste slag and iron oxalate-containing leaching liquid; (3) adding phosphoric acid or a phosphoric acid solution into the iron oxalate-containing leaching liquid, converting the iron oxalate into iron phosphate precipitate, and performing solid-liquid separation to obtain iron phosphate and a separating liquid; (4) washing and drying the obtained iron phosphate to obtain an iron phosphate product; and (5) taking the separating liquid obtained in the step (3) as the leaching agent to continue leaching the iron in the soft manganese ore leaching slag, and forming a recycling process in such a manner. According to the method provided by the invention, the iron resource in the soft manganese ore leaching slag can be recycled and utilized, and meanwhile, environmental harm of the soft manganese ore leaching slag is reduced.

The invention relates to a preparation method of monoclinic ferrous oxalate crystal (FeC2O4.2H2O) with particlesize less than 3mum and the monoclinic ferrous oxalate crystal with particlesize less than 3mum obtained by adopting the method. A solid-liquid two-phase method is adopted and the reaction is controlled by controlling the feeding speed of solid oxalate and the temperature and concentration of bivalence ferrous salt solution, thus achieving the purpose of generating the ferrous oxalate crystals with specific crystal formation and particlesize. The method is characterized in that: the solid oxalate is added into the bivalence ferrous salt water solution with concentration of Fe2+ being 0.5-1.7mol/l at the temperature of 40-80 DEG C at the feeding speed of more than 500g/min for reaction by temperature preservation. The method has simple process and high yield. The ferrous oxalate crystal with particlesize less than 3mum is obtained by the method, and the crystal formation is the monoclinic crystal.

The invention provides a preparation method for a carbon wave-absorbing material. The carbon wave-absorbing material is composed of a carbon matrix material, a heat conduction carbon fiber, butyl acrylate and a 819 photo-initiator, the carbon matrix material is prepared from a reaction of activated carbon sponge, mesoporous carbon, a heat conduction carbon fiber, a nano carbon material and ferrite, the heat conduction carbon fiber is prepared by reacting a carbon fiber, copper acetate, Sr-10 emulsifiers, thiourea, water, ethanol, glucose and ammonia water, and the ferrite is prepared by reacting iron oxalate, cobalt oxalate, nickel oxalate, nano copper powder, acrylic acid, methoxy polyethylene glycol 550 monomethacrylate, and the 819 photo-initiator. The carbon wave-absorbing material prepared by the method of the invention has excellent wave-absorbing properties.

The invention discloses a preparation method and application of a carbon-nitrogen co-doped iron-cobalt-based catalyst, and the preparation method comprises the following steps: S1, dissolving an iron salt and a cobalt salt in deionized water, and magnetically stirring at 50-80 DEG C for 3-5 hours to obtain a mixed solution; S2, dropwise adding an isometric 0.4-0.5 mol/L sodium oxalate solution into the mixed solution, stirring and reacting at 20-60 DEG C for 6-12 hours, filtering and drying; S3, placing the obtained cobalt iron oxalate precursor in a tubular furnace, carrying out heat treatment at 300-600 DEG C for 1-3 hours, introducing a mixed gas of CH4 and NH3 at a flow rate of 250-500 sccm, carrying out vapor deposition for 2-4 hours, and grinding to a micro-nano level; and S4, adding a carbon source sol solution into the obtained iron-cobalt material, carbonizing for 1-3 hours, introducing NH3 at the flow rate of 200-400 sccm under the condition of 500-600 DEG C, continuously treating for 0.5-1.5 hours, activating, carrying out secondary vapor deposition, cooling, crushing, washing and drying. The metal elements Fe and Co and oxides thereof form a defect energy state between a valence band and a conduction band by doping non-metal elements carbon and nitrogen, so that lattice distortion is caused, and the catalytic activity and directional selectivity of the catalyst are improved.

The invention discloses a carbon nanotube modified silicone rubber material. The carbon nanotube modified silicone rubber material comprises the following raw materials: silicone rubber, polyasparticacid ester, ethylene-acrylate rubber, silicon dioxide aerogel, carbon nanotubes, iron oxalate, montmorillonite, halloysite, polyvinyl alcohol fiber, glass fiber, zinc oxide, a silane coupling agent, 2,5-dimethyl-2,5-di(tert-butylperoxyl)hexane, benzoperoxide, an accelerator DM, N,N'-bis(salicylidene)-1,2-propanediamine and N-hydroxymethyl-3-(dimethoxyphosphonyl)propionamide. The carbon nanotube modified silicone rubber material provided by the invention has the advantages of good heat resistance, excellent aging resistance and flame retardancy and high strength.

The invention provides a method for preparing ferrous oxalate hydrated salt crystals. The method comprises the following steps: carrying out the contact reaction between a solution A and a solution B. The contact manner and condition of the solution A and the solution B are provided to allow the produced ferrous oxalate hydrated salt to be supersaturated in the reaction mixed solution of the solution A and the solution B. By adopting the method, the prepared ferrous oxalate hydrated salt crystals have smaller average particle size and higher purity.

The invention discloses a method for leaching gold hematite wrapped in second-stage calcine through using oxalic acid. The method comprises the steps that firstly, the oxalic acid is added into a leaching tank; the second-stage calcine and water are added into the leaching tank added with the oxalic acid, agitation leaching is carried out, and liquid-solid separation is carried out after the leaching process is ended so as to obtain a leachate and leaching residues; illumination treatment is carried out on the leachate to obtain a faint yellow precipitate and an illuminated solution; and cyaniding leaching is conducted on the leaching residues, liquid-solid separation is conducted after the leaching process is finished, and accordingly gold-containing pregnant solution is obtained. According to the method, the oxalic acid is added, the strong complexing effect of C2O4<2-> on Fe<3+> is utilized, the hematite in the second-stage calcine is leached in the form of an iron oxalate complex,the iron leaching speed is high, the iron leaching rate is high, the energy consumption in the leaching process is low, and industrialization is easy; the leachate is subjected to illumination treatment to obtain ferrous oxalate, part of the oxalic acid is re-used, and recovering of iron, recycling of part of leaching agent oxalic acid and re-using of the system water are achieved; and cyaniding is conducted on iron removal slag for gold extraction, and the leaching rate of gold is effectively increased.

The invention provides a seal rubber mat capable of preventing salt corrosion. The seal rubber mat is made from silicone rubber, fluororubber, an anti-aging agent DNP, an anti-aging agent CMA, white carbon black, calcium carbonate, iron oxalate, an accelerator NOBS, an accelerator DPTH, t-butyl perbenzoate, benzoyl peroxide and epoxy resin. The preparation method comprises the steps that (1) the fluororubber is subjected to plastication; (2) after the plastication, the fluororubber is mixed with the silicone rubber and other components in an open mill for mixing; (3) the rubber compound is subjected to remilling; (4) extrusion forming and vulcanization are carried out, and the seal rubber mat is obtained. The seal rubber mat has the advantages of smooth surfaces, strong resistance to corrosion and long service life, simple preparation process, reasonable components and safe production during the preparing process.