43 results about "Metaphosphoric acid" patented technology

The invention belongs to the technical field of preparation processes of barium metaphosphate, and particularly relates to a preparation method of monodisperse micron-sized barium metaphosphate. The preparation method comprises the following steps: mixing purified barium carbonate slurry and phosphoric acid according to a certain molar ratio, reacting to obtain barium dihydrogen phosphate slurry, adding ethanol and a particle size regulating agent, uniformly mixing, and carrying out spray drying to obtain a crude product; the particle size regulating agent comprises ammonium citrate, polyalcohol and barium metaphosphate; and calcining the crude product to obtain the product monodisperse micron-sized barium metaphosphate. According to the preparation method, a small amount of particle size regulating agent and a certain amount of ethanol are added, a crude product with uniform particle size distribution is prepared under a spray drying process condition, and then calcination is performed to obtain the micron-sized barium metaphosphate with uniform particle size distribution.

The application discloses a kind of high flame-retardant tpe materials and preparation method thereof, by polytetrahydrofuran, modified monomer and 4,4'-dicyclohexyl methane diisocyanate are reacted, chain extension is used with 1,4-butanediol, finally join flame-retardant additive, form branched structure, and the molecular structure of the pte material is branched structure, and molecular chain segment contains organic silicon composite organic phosphorus structure, when heat decomposition, can generate phosphoric acid, poly-metaphosphoric acid and other acidic substances, these acidic substances will catalyze pte molecule to occur dehydration reaction, accelerate its crosslinking, organic silicon chain segment will produce inorganic silicate or silicon-carbon, and then form a dense carbon layer on the surface of material, can heat insulation and oxygen isolation, prevent combustible gas to escape outward and oxygen diffusion inward, and slow down the further thermal decomposition of internal material, prevent carbon layer from being burnt through or collapse under high temperature, improve the durability of barrier, so that pte material has good flame-retardant effect.

This invention relates to the field of polymer materials technology, specifically disclosing a flame-retardant thermoplastic elastomer compound and its preparation method. The flame-retardant thermoplastic elastomer compound comprises 50-80 parts SEBS, 10-30 parts PP, 5-15 parts compatibilizer, 10-30 parts composite flame retardant, 3-10 parts plasticizer, 0.2-1 parts antioxidant, and 0.1-0.5 parts lubricant. The composite flame retardant is prepared by reacting and mixing an intumescent flame retardant, barium metaphosphate, boron nitride, triallyl isocyanurate, and SEBS. The flame-retardant thermoplastic elastomer compound of this application possesses good flame retardancy, mechanical properties, and water resistance stability.

The present application relates to the technical field of lithium ion battery recycling, in particular to a method for stripping lithium ion battery pole piece and application thereof. The method for stripping lithium ion battery pole piece comprises: immersing the pole piece into a mixed solution containing a stripping agent and a stripping aid for reaction, and obtaining the separated active material layer and the current collector layer after a period of time; the stripping agent comprises a carboxylic acid containing at least two carboxyl groups; the stripping aid comprises at least one of sodium fluoride, potassium fluoride, ammonium fluoride, phosphoric acid, sodium phosphate, monosodium phosphate, sodium metaphosphate, potassium phosphate, monopotassium phosphate, potassium metaphosphate, ammonium phosphate, disodium ethylenediaminetetraacetate, tetrasodium ethylenediaminetetraacetate, inositol hexaphosphate and its salt, inositol pentaphosphate and its salt, inositol tetraphosphate and its salt, and inositol triphosphate and its salt. The method can realize the separation of the active material and the current collector, the hydrogen production amount is small during the whole stripping process, the current collector obtained after stripping is intact, the separation time is short, and the separation efficiency is high.

The invention relates to a part made from synthetic graphite, preferably isostatic synthetic graphite, impregnated with aluminium metaphosphate Al(PO3)3, and characterised in that the aluminium metaphosphate content is at least 1% by weight for the cubic form and does not exceed 0.4% by weight, and preferably does not exceed 0.3% by weight, for monoclinic forms. Such a part has good resistance to oxidation and can be used under hydrothermal conditions.

The present invention provides a liquid enzyme preparation of an enzyme having excellent activity stability. Stability of enzymatic activity is improved by accommodating a liquid enzyme preparation that includes an enzyme into a container the internal space of which has been replaced by an inert gas, or by adding, to a liquid enzyme preparation containing a protein deamidase, an additive selected from the group consisting of sugar alcohols, glycerin, ethanol, sulfites, lecithins, citrates, polyphosphates, tartrates, phytic acid, metaphosphoric acid, sodium chloride, tocotrienols, methionine, pectins, beet pigment, capsicum pigment, rosemary extract, tocopherols, tea extract, and butylated hydroxyanisole.

The application provides a preparation method of high-content 2-trifluoromethyl-4-heptafluoroisopropylaniline, in which 2-trifluoromethyl aniline and 2-bromine heptafluoropropane are reacted in the presence of hydrosulfite, a solvent and a catalyst to obtain high-content 2-trifluoromethyl-4-heptafluoroisopropylaniline through reaction and post-treatment; the catalyst is selected from phosphoric acid, pyrophosphoric acid, hypophosphorous acid, metaphosphoric acid, phosphorous acid, pyrophosphorous acid, hydrobromic acid, hydrogen bromide gas, hydrogen chloride gas or sodium bisulfite. The preparation method is simple in operation and mild in chemical reaction conditions; under the preferred reaction conditions, the conversion content reaches more than 96% in one reaction, the post-treatment steps are few, rectification is not needed, the content of the final product is more than 98%, the total reaction yield is more than 93%, the industrial production is easy, and the method has a high application prospect.

The present application relates to a kind of high hardness polyurethane and its preparation method and application.The phosphorus-containing polyol structural formula is as follows: the phosphorus-containing polyol is prepared by ester exchange reaction using phosphorus-containing diol and dialkyl carbonate.High hardness flame-retardant thermoplastic polyurethane elastomer is prepared from the phosphorus-containing polyol.The phosphorus-containing polyol can decompose phosphoric acid, metaphosphoric acid and other substances during heating, promote the dehydration and carbonization of polyurethane, and form a dense carbon layer that is not easy to burn, thereby achieving excellent flame-retardant effect.

The invention discloses a metaphosphoric acid rapid cooling device and a use method thereof. The metaphosphoric acid rapid cooling device comprises a cylindrical barrel; the barrel cover covers the top of the cylindrical barrel body; the feeding hole is formed in the center of the cylinder cover; the chassis is hermetically and rotatably connected with the bottom of the cylindrical barrel; the telescopic rod comprises a sleeve and a piston rod, and the sleeve is fixedly connected with the center of the chassis; the large bottom of the conical drainage piece is fixedly connected with the tail end of the piston rod, and the conical head part of the cylindrical drainage piece corresponds to the feeding hole; the annular cavity is distributed around the inner wall of the cylindrical barrel and surrounds the telescopic rod and the conical drainage piece, a first gap is reserved between the edge of the conical drainage piece and the inner wall of the annular cavity, and a second gap is reserved between the bottom of the annular cavity and the base plate; and the cooling medium is filled in the annular cavity. The metaphosphoric acid cooling device has the beneficial effects that metaphosphoric acid is cooled for multiple times, and the cooling rate is increased.

This invention relates to the field of health food testing technology, and particularly to a method and system for rapid determination of ascorbic acid enantiomer content in health foods using ultra-high performance phase chromatography (UHPLC). After extraction with metaphosphoric acid solution via ultrasonication in the dark, centrifugation, and filtration, the sample is separated using a Waters Acquity BEH column. Gradient elution is performed using supercritical carbon dioxide and 0.1% phosphoric acid methanol solution as the mobile phase, under conditions of 13.8 MPa system back pressure, 31 °C column temperature, and 245 nm detection wavelength. The contents of D(−)-ascorbic acid and L(+)-ascorbic acid are determined using the external standard method. This invention can achieve effective separation of the two ascorbic acid enantiomers in a short time, and has advantages such as fast analysis speed, good separation effect, high accuracy, good repeatability, and low organic solvent consumption. It is suitable for quality control and regulatory detection of ascorbic acid enantiomers in various health foods such as tablets, capsules, and liquids.

The invention relates to an optical cable belting material with high flame retardance and high resistivity, and belongs to the technical field of flame-retardant materials. The preparation method of the optical cable belting material comprises the step of coating the calcium carbonate powder and the intumescent flame retardant on a base material through vinyl acetate-ethylene copolymer emulsion and water to obtain the optical cable belting material. When the optical cable belting material is combusted, the calcium carbonate powder and the intumescent flame retardant are subjected to chemical reaction in flame combustion to form a calcium metaphosphate / carbonaceous composite flame-retardant coating, and the flame-retardant coating is constructed by embedding lamellar calcium metaphosphate continuous networks in a carbon layer. The calcium metaphosphate continuous network can control the combustion process of the composite coating, and the peak heat release rate and the smoke generation rate are remarkably reduced; and the expansion degree and the structural uniformity of the carbon residues are effectively improved, and a conductive path of a carbon layer is destroyed, so that the surface resistivity of the flame-retardant coating is improved. The preparation process is simple, the coating performance is excellent, and the coating is suitable for high-flame-retardant and high-resistivity optical cable belting materials.

The application relates to the technical field of heat-sensitive materials, and discloses a film-coated heat-sensitive material and a preparation method thereof. The application is characterized by the following steps: preparing a base material, cutting the base material into a required shape and size, coating a heat-sensitive dye, uniformly spraying the heat-sensitive dye on the base material, drying the base material coated with the heat-sensitive dye, preparing a finished product, cutting the dried base material into a required final product shape and size, and obtaining the film-coated heat-sensitive material. The modified polyurethane and boron element in the phosphorus-containing flame retardant have good flame-retardant effects. In the combustion process, the phosphorus element in the phosphorus-containing flame retardant decomposes into a non-flammable liquid film of phosphoric acid, further generates metaphosphoric acid and poly-metaphosphoric acid, these substances form a protective layer on the material surface, isolate oxygen and high temperature, and have the flame-retardant effect. The quaternary ammonium salt in the quaternary ammonium chain extender has good antibacterial effect.

The invention relates to a sealing solution and a preparation method and application thereof, and relates to the technical field of anodic oxidation. The invention provides a preparation method of a sealing solution, which comprises the following steps: (1) mixing a fluotitanic acid solution, a zirconium fluoride solution, a glycerol solution, a sodium metaphosphate solution and water to obtain a stock solution; and (2) adding pure water into the stock solution, and uniformly stirring to obtain a closed solution. When the prepared sealing solution is used for preparing a part oxide layer, a surface film layer with ultrahigh sealing performance and excellent corrosion resistance can be obtained, the vacuum leak rate of the surface film layer is as low as 10-12 Pa.L / s, the corrosion-resistant hydrochloric acid Bubble test exceeds 4 h, and the requirements for ultrahigh sealing performance and excellent corrosion resistance are met.

The invention discloses a preparation method of a caprolactam ammoniation catalyst, the caprolactam ammoniation catalyst and application, and belongs to the field of catalysis. Comprising the following steps: S1, mixing a carrier with an alkali solution, treating I, drying I and roasting to obtain a treated carrier; s2, mixing an active component precursor solution with the treated carrier, dipping, and drying II to obtain a catalyst precursor; and S3, treating the catalyst precursor II in a water vapor atmosphere to prepare the caprolactam ammoniation catalyst, the active component precursor is selected from at least one of phosphoric acid, metaphosphoric acid, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, polyphosphoric acid, phosphomolybdic acid and phosphotungstic acid. The prepared catalyst is applied to a reaction for preparing 6-aminocapronitrile through caprolactam ammonification, has high conversion rate and selectivity, also has high stability, and can stably operate for a long period.

The invention relates to the technical field of battery materials, and discloses a lanthanum metaphosphate coated lithium cobalt oxide composite material and a preparation method thereof. The preparation method comprises the following steps: taking trivalent metal lanthanum salt and phosphate as raw materials, obtaining high-purity lanthanum metaphosphate through a solid phase method, then dispersing the lanthanum metaphosphate into a solvent, adding lithium cobalt oxide, and carrying out wet coating, so as to obtain the lithium cobalt oxide material coated with a lanthanum metaphosphate shell. The lanthanum metaphosphate coated lithium cobalt oxide composite material provided by the invention has excellent conductivity, rate capability and cycle performance.

The invention relates to the technical field of sodium-ion battery positive electrode materials, and discloses a sodium-ion battery positive electrode material and a preparation method thereof, a sodium-ion battery and electric equipment. The sodium-ion battery positive electrode material comprises a substrate and a coating layer coating at least part of the surface of the substrate, the chemical formula of the substrate is NaxNiaFebMncMdO2, x is greater than or equal to 0.85 and less than or equal to 1.1, a is greater than 0 and less than 1, b is greater than 0 and less than 1, c is greater than 0 and less than 1, d is greater than 0 and less than 0.5, a + b + c + d = 1, and M is selected from at least two of Ti, Mg, Cu, Ca, Al, Zn, La, Cr, Y, Ce, Si, Sn and W; the coating layer comprises metaphosphoric acid metal salt, and metal elements in the metaphosphoric acid metal salt are selected from at least one of Y, La, Al, Li, Na, Ba and Ca. The battery positive electrode material provided by the invention is applied to the sodium-ion battery, so that the sodium-ion battery has good cycling stability and excellent specific capacity.

This invention provides a multi-component system, particularly a two-component mortar system, that overcomes the shortcomings of conventional systems. [Solution] The above problems are solved by a two-component mortar system for chemical fixation of fasteners in a mineral substrate, comprising a curing aqueous phase alumina cement component A and an initiator component B in the aqueous phase for initiating a curing process, wherein component A further comprises at least one blocking agent selected from the group consisting of boric acid, phosphoric acid, metaphosphoric acid, phosphorous acid, and phosphonic acid, and water, and component B comprises blocked blast furnace granulated slag, water, and optionally at least one mineral filler, and a ready-to-use two-component system for chemical fixation of fasteners in a mineral substrate such as brickwork, concrete, permeable concrete, or natural stone structures, preferably metallic elements, and its use for chemical fixation of fasteners.

The present application relates to the field of biological products and veterinary medicine, and discloses a method for extracting and purifying blood gonadotropin, which comprises the following steps: 1) adjusting the pH of pregnant mare serum to 4.5-5.0 by using metaphosphoric acid, and performing solid-liquid separation to collect supernatant; 2) precipitating the supernatant by using a first precipitant, and collecting filtrate; 3) precipitating the filtrate by using a second precipitant, collecting precipitate, and drying the precipitate to obtain crude blood gonadotropin; 4) dissolving the crude blood gonadotropin, and sequentially performing first ultrafiltration, affinity chromatography, second ultrafiltration, and cation exchange chromatography to obtain crude blood gonadotropin filtrate; precipitating the crude blood gonadotropin filtrate by using a third precipitant, collecting precipitate, and drying the precipitate to obtain pure blood gonadotropin. The purity of the blood gonadotropin prepared by the extraction and purification method can reach more than 99.9%, the total yield can reach 88.9%, and the titer can reach 11000 IU / mg.

The invention discloses a soldering flux for welding a lead-acid storage battery, which is characterized by comprising the following components in percentage by weight: 20-25% of a deoxidant, 10-20% of an activator, 2-5% of a surfactant, 1-2% of a corrosion inhibitor, 2-3% of an additive and the balance of a solvent, the deoxidant is any one of phosphoric acid, phosphorous acid and metaphosphoric acid; the activating agent is any one of oxalic acid, succinic acid, glutaric acid, citric acid, malic acid and tartaric acid; the surfactant is any one of polyoxyethylene ether, sodium dodecyl benzene sulfonate, alkyl betaine and perfluoroalkyl sulfonate; the corrosion inhibitor is any one of triethanolamine, octadecylamine, hexadecyl trimethyl ammonium bromide, benzimidazole and benzotriazole; the additive is ethyl acetate and s-triazine in a ratio of 4: 3; the solvent is any one of ethylene glycol, propylene glycol ether, propylene glycol, glycerol and 1, 4-butanediol. The method aims to solve the problem of halogen element residues in the cast welding process of the lead-acid storage battery.

The invention discloses a fireproof cable and a preparation method thereof, and relates to the technical field of cables. Transition metal oxide, ammonium polyphosphate and silicon dioxide are attached to the surface of a hollow glass bead wall material, and hybrid hollow glass beads are prepared through segmented high-temperature treatment to serve as filler and are added into rubber. Heating an ammonium polyphosphate molecular chain at a low temperature, dehydrating and condensing to generate pyrophosphoric acid and metaphosphoric acid with high polymerization degree, and forming a three-dimensional cross-linked P-O-Si bond network; during medium-temperature heating, transition metal oxide is coordinated with polyphosphoric acid during medium-temperature heating to generate a Fe-P-O composite phase coordination network; and during high-temperature heating, the transition metal oxide and silicon dioxide generate high-hardness nano-crystalline grains which are embedded into a P-O-Si glass network, so that a flame-retardant effect is achieved. The hybrid hollow glass beads are combined with a flexible polymer, a buffer layer is provided, stress concentration points are reduced, and the tensile strength of rubber is reserved; and finally, an amine-terminated polyether flexible chain segment chain extender is added, so that the network ductility is improved. The cable prepared by the invention has fireproof and high-stability effects.

The invention discloses a high flame-retardant tpe material and a preparation method thereof.The preparation method comprises the steps that polytetrahydrofuran, a modified monomer and 4, 4 '-dicyclohexylmethane diisocyanate react, then 1, 4-butanediol is used for chain extension, finally, a flame-retardant additive is added, a branched structure is formed, the tpe material is prepared, the molecular structure of the pte material is the branched structure, and the flame-retardant property of the pte material is improved. A molecular chain segment contains an organic silicon composite organophosphorus structure, acidic substances such as phosphoric acid and polymetaphosphoric acid can be generated when the organic silicon composite organophosphorus structure is heated and decomposed, the acidic substances can catalyze pte molecules to be subjected to a dehydration reaction and accelerate crosslinking of the pte molecules, and the organic silicon chain segment can generate inorganic silicate or silicon-carbon, so that a compact carbon layer is formed on the surface of the material; the flame-retardant PP material has the advantages that heat and oxygen can be insulated, combustible gas is prevented from escaping outwards, oxygen is prevented from diffusing inwards, further thermal decomposition of internal materials is slowed down, a carbon layer is prevented from being burnt through or collapsed at a high temperature, the durability of a barrier is improved, and the PP material has a good flame-retardant effect.

The present invention discloses a pressurizing system for a furnace tube, which relates to the technical field of crystalline silicon battery manufacturing. The furnace tube includes a furnace tube body, an air intake pipe and a tail exhaust pipe are installed on the furnace tube body, and the air intake pipe, the furnace tube body and the tail exhaust pipe form a gas flow path. The pressurizing system includes a nitrogen storage box and a bypass pipe. Nitrogen is stored inside the nitrogen storage box, and a heat exchange component is installed inside the nitrogen storage box. The heat exchange component is used to heat the nitrogen to increase the air pressure inside the nitrogen storage box. The heat exchange component is installed on the tail exhaust pipe, and the bypass pipe is fixed in parallel on the air intake pipe. The bypass pipe can inject the nitrogen inside the nitrogen storage box into the air intake pipe. The heat exchange component includes a heat exchange pipe and a heat exchange fin. The present invention transforms the original water bottle nitrogen pipeline. Without affecting the cooling of the tail gas and the collection of metaphosphoric acid, it fully utilizes the nitrogen on the water bottle nitrogen pipeline to increase the back pressure gas volume, thereby reducing the back pressure time and improving production capacity.

This invention relates to the field of mineral-based solid waste resource recycling, specifically to a solid waste-based homogeneous slurry and its preparation method. Using mineral-based solid waste as the core raw material, supplemented with water, grinding aids, and potential regulators, a stable solid waste-based homogeneous slurry is prepared through a complete process including raw material pretreatment, coarse grinding, fine grinding, graded closed-loop screening, precise Zeta potential control, and ultrasonic homogenization. This slurry can be used with composite solidifying agents to prepare solidified soil for engineering applications. This invention establishes a precise matching mechanism between the calcium content of solid waste and the potential regulator. Potassium hexapolymetaphosphate is preferred for high-calcium mineral-based solid waste, while sodium pyrophosphate is preferred for low-calcium mineral-based solid waste. It is suitable for all types of high-calcium and low-calcium bulk mineral-based solid waste. The prepared slurry exhibits excellent homogeneity and can be stored for a long time. The solidified products have high mechanical strength and low performance dispersion. The preparation process parameters are controllable and suitable for large-scale continuous production, showing broad application prospects.

A synthetic graphite part, preferably isostatic, impregnated with aluminum metaphosphate Al(PO3)3, and characterized in that the aluminum metaphosphate content is at least 1 wt% for the cubic form and does not exceed 0.4 wt%, and preferably does not exceed 0.3 wt%, for the monoclinic forms. Such a part has good resistance to oxidation and can be used under hydrothermal conditions.

The invention relates to the field of food, and provides a method for detecting furfural furan substances in dairy products, and the method comprises the following steps: mixing a dairy product to be detected with a metaphosphoric acid solution, filtering, and collecting a first filtrate to obtain a pretreatment solution; detecting the pretreatment liquid by using a high performance liquid chromatography to obtain a detection result; and based on the detection result, determining the content of furfural furan substances in the dairy product to be detected. According to the method, the furfural furan substances can be effectively separated and extracted from the dairy products, the content of the furfural furan substances can be accurately detected by combining the high performance liquid chromatography, and the method is low in detection limit, easy and convenient to operate, low in cost and suitable for application and popularization.

The invention relates to the technical field of metaphosphate preparation, in particular to a preparation method of monodisperse micron-sized magnesium metaphosphate, which comprises the following steps: (S1) adding basic magnesium carbonate into a reaction container, adding water to prepare slurry I, slowly adding phosphoric acid, heating to 30-40 DEG C, continuously and slowly adding phosphoric acid, heating to 50-60 DEG C, concentrating, dehydrating, washing and drying to obtain a solid; (S2) preparing slurry II from the solid and deionized water, adding ethanol and a particle size regulating agent, uniformly mixing, and performing centrifugal spray drying to obtain a crude product; the particle size regulating agent is prepared from magnesium stearate, polyol, polyvinyl alcohol and nanoscale magnesium metaphosphate; and (S3) calcining the crude product to obtain a monodisperse micron-sized magnesium metaphosphate product. According to the preparation method disclosed by the invention, a crude product with uniform particle size can be obtained by spray drying, adding ethanol and a particle size regulating agent and reasonably controlling a formula and spray drying parameters, and finally, the crude product is calcined to obtain the monodisperse micron-sized magnesium metaphosphate.

The application discloses a beneficiation method for recovering tungsten from polymetallic tungsten tailings, and is characterized by comprising the following steps: obtaining strong magnetic concentrate and strong magnetic tailings through strong magnetic separation; concentrating the strong magnetic concentrate to a slurry with a concentration of 30%, adding sodium carbonate to the slurry to make the pH value of the slurry reach 7.0-9.0, then adding sodium hexametaphosphate, OS, salted water glass, lead nitrate and a tungsten capturing agent, and then feeding the mixture into a flotation machine to obtain wolframite concentrate and wolframite tailings; adjusting the strong magnetic tailings to a slurry with a concentration of 30%, adding oxalic acid, water glass and a capturing agent LLR to the slurry, and then feeding the mixture into a flotation machine to obtain scheelite-fluorite concentrate and co-floating tailings; and concentrating the scheelite-fluorite concentrate to a slurry with a concentration of 30%, and then performing 'one roughing and three cleaning' centrifugal gravity separation to obtain scheelite concentrate and fluorite concentrate. Under the acid condition, the flotation effect of the fluorite is enhanced, the interference on the scheelite flotation is reduced as much as possible, and the recovery rate and grade of the wolframite concentrate and the scheelite concentrate are improved.

The invention discloses a preparation method of lithium difluorophosphate, which is prepared by taking lithium metaphosphate as a phosphorus source and hydrogen fluoride as a fluorinating reagent and then separating to obtain a product, and mainly comprises the following steps: dispersing lithium metaphosphate in a supercritical carbon dioxide solvent, and introducing hydrogen fluoride to fully react to obtain lithium difluorophosphate and water; and after the reaction is finished, discharging the supercritical carbon dioxide fluid, and carrying out cooling and depressurization separation to obtain the lithium difluorophosphate. The preparation method disclosed by the invention is simple to operate, efficient in reaction, convenient to separate, green and environment-friendly.

This invention discloses a method for preparing and applying an Eu-doped Ni(PO3)2 porous nanosheet electrocatalyst. The method uses carbon cloth as a substrate, europium inorganic salt as the europium source, nickel inorganic salt as the nickel source, amino acids as rare earth anchoring agents, ammonium fluoride as a precipitant, and urea as a reducing agent. A carbon cloth-supported Eu-doped Ni(OH)2 precursor is synthesized via a hydrothermal reaction, and the catalyst is finally prepared by a low-temperature phosphating process in an Ar / H2 atmosphere. This invention dops europium into nickel metaphosphate; the synergistic effect of europium and nickel improves the catalytic activity and stability of the catalyst. Furthermore, the catalyst exhibits good morphology retention and high selectivity for the oxygen evolution reaction (OER), showing promising market prospects.

Disclosed in the present invention is a passivation treatment liquid for a tinplate, which passivation treatment liquid comprises: chromic anhydride, which has a content of 15-30 g / L; metaphosphoric acid and / or a metaphosphate, which has a content of 5-15 g / L; ammonium bromide, which has a content of 1-5 g / L; and a nitrogen-containing organic compound, which has a content of 0.2-2 g / L. Further disclosed in the present invention are a tinplate treated with the passivation treatment liquid and a method for manufacturing the tinplate. The surface of the tinplate has good coating wettability and better paint film adhesion.