239 results about "CHROMIC NITRATE" patented technology

The invention relates to a sponge composite metallic organic framework material for adsorption separation and belongs to the technical field of materials. According to the invention, a two-step in-situ growth method is adopted for loading MOFs (metallic organic framework material) into a duct in a sponge carrier. The MOFs is synthesized from following organic ligands and metal salts, wherein the organic ligands include pyrazine, trimesic acid, terephthalic acid, 2,5-dihydroxyterephthalic acid, and the metal salts include cupric fluosilicate, magnesium nitrate, zirconium chloride, cupric nitrate, chromic nitrate, ferric nitrate, aluminum nitrate and hydrates thereof. According to a preparation method provided by the invention, a large amount of MOFs loaded in the duct in the sponge carriercan be realized; MOFs load rate is high; load is stable; the defects of fragility and easiness in loss of MOFs powder can be overcome; a breakthrough experiment proves that the material provided by the invention has the characteristics of high CO2-absorbing capacity, high adsorption separation selectivity, stable adsorption separation property, and the like.

The invention belongs to the technical field of photocatalyst materials and discloses a molybdenum disulfide/MIL-101 composite photocatalyst material, a preparation method thereof and application in the field of antibiotic wastewater degradation treatment, in particular application in the field of degradation of antibiotic wastewater containing ciprofloxacin. The preparation method comprises the following steps: dissolving chromic nitrate, terephthalic acid and hydrofluoric acid into water, uniformly stirring, heating and reacting to obtain MIL-101; dissolving sodium molybdate and thioacetamide into water, uniformly stirring, then adding the MIL-101 obtained in the step (1), uniformly stirring, heating and reacting to obtain the MoS2/MIL-101 composite photocatalyst material. The photocatalyst material disclosed by the invention contains highly dispersed MoS2 nanosheets and more exposed MoS2 active edges, has excellent composite photocatalytic performance and can be applied to antibiotic wastewater degradation treatment, especially realization of efficient degradation treatment on the antibiotic wastewater containing ciprofloxacin.

The invention discloses a method for preparing dispersion strengthening ferritic alloy steel powder of nanometer yttrium oxide particles. The method includes adding ethylene diamine tetraacetic acid and chromic nitrate into water, stirring the mixture at a temperature in a range from 50 DEG C to 60 DEG C for at least 12 hours, and obtaining a mixed liquid; adding citric acid, ferric nitrate, ammonium paratungstate, yttrium nitrate and tetrabutyl titanate into the mixed liquid, mixing the mixture at a temperature in a range in a range from 60 DEG C to 70 DEG C for at least 3 hours, and obtaining colloidal sol; adding polyethylene glycol into the colloidal sol, stirring the mixture at a temperature in a range in a range from 70 DEG C to 80 DEG C to form gel; and finally drying the gel at a temperature in a range from 100 DEG C to 120 DEG C for at least 12 hours and roasting the gel at a temperature in a range from 300 DEG C to 600 DEG C for 4 to 5 hours in sequence to obtain precursor oxide powder, placing the gel in a reducing atmosphere, roasting the gel at a temperature in a range from 1100 DEG C to 1300 DEG C for at least 3 hours to obtain object products which comprise, by weight, 12% to 14% of chromium, 2% to 3% of tungsten, 0.2% to 0.5% of titanium, 0.1% to 1% of yttrium oxide, and the balance iron. Yttrium oxide is evenly dispersed and distributed on matrixes composed of chromium, tungsten, titanium and iron, and the products can be used in fast breeder reactors and fusion reactors.

The invention discloses a preparation method of three-dimensional ordered macroporous La1-xSrxCrO3 (x=0, 0.4) with a mesoporous pore wall. The preparation method comprises the following steps of: dissolving lanthanum nitrate and chromium nitrate in mixed liquid of polyethylene glycol 400 and absolute methanol in the molar ratio of 1:1 or dissolving lanthanum nitrate, strontium nitrate and chromium nitrate in mixed liquid of polyethylene glycol 400, absolute methanol and deionized water in the molar ratio of 0.6:0.4:1; adding citric acid in the molar ratio of 1:1 of chromium nitrate to citric acid; performing ultrasonic treatment; adding absolute methanol solution of P123 and performing ultrasonic treatment so as to form homogeneous solution; adjusting metal ion concentration to be 2.0 mol/L; and pouring a polymethyl methacrylate (PMMA) microsphere template into the solution, soaking, performing suction filtration, drying and baking the obtained substance in two steps. The La1-xSrxCrO3prepared by the preparation method has high degree of crystallization, controllable particle shape and pore size, readily available raw materials, high product stability, high electrical conductivityand good application prospect.

The invention provides a method for preparing a Tb/Cr-codoped high-remanent-polarization BiFeO3 film by a sol-gel process, which comprises the following steps: dissolving bismuth nitrate, ferric nitrate, terbium nitrate and chromic nitrate in a mol ratio of 0.94:(1-x):0.11:x in a mixed solution of ethylene glycol monomethyl ether and acetic anhydride, and adding ethanolamine to obtain a stable BiFeO3 precursor solution, wherein the total metal ion concentration in the BiFeO3 precursor solution is 0.3 mol/L, and x=0.01-0.03; and carrying out spin coating and layer-by-layer annealing to obtain the Tb/Cr-codoped crystalline BiFeO3 film. The facility requests are simple, the experimental conditions are each to achieve, the film has favorable uniformity, the doping amounts of Tb and Cr can be accurately controlled, and the crystal structure can be adjusted by codoping to greatly enhance the ferroelectric properties of the film, so that the saturated remanent polarization of the film can reach 80.8 mu C/cm<2>.

The invention relates to a preparation method for chromium oxide (Cr2O3) nanometer materials, belonging to the technical field of inorganic material preparation. The preparation method comprises the steps: by taking chromic nitrate as raw materials, firstly carrying out hydrolysis to the chromic nitrate to generate hydrated chromium oxide nano particles through hydrothermal reaction under neutral or acidic conditions, and then the hydrated chromium oxide nano particles is performed with thermal calcination treatment so as to be crystallized into chromium oxide nanometer materials. According to the preparation method, the raw materials are non-toxic and harmless, no reducing agent, surface active agent or precipitating agent are needed, and the prepared nanometer chromium oxide has high purity, good specific surface area and excellent thermal stability. The particle size distribution is even, the chromium oxide nano particles with different particle sizes ranging from 20nm to 200nm can be obtained through simply regulating the acidity or calcination temperature of experiments. The method has low cost, is simple in production technique and easy for industrial large-scale production, and has no generation of chromium-containing wastes in the whole technique, thereby being an environment-friendly and clean method for preparing chromium oxide.

The invention discloses a ternary CoFeCr hydrotalcite nanorod and a preparation method and application thereof. The preparation method comprises the steps: mixing cobalt nitrate, iron nitrate, chromium nitrate, urea and ammonium fluoride in water so as to prepare a precursor mixed solution, placing a substrate in the precursor mixed solution, transferring the substrate together with the precursormixed solution to an autoclave, and then performing a reacting at 110-130 DEG C for 360-600 minutes so as to prepare the ternary CoFeCr hydrotalcite nanorod on the substrate. The ternary CoFeCr hydrotalcite nanorod together with the substrate is directly used as a working electrode for electrochemical decomposition of water. Not only the ternary CoFeCr hydrotalcite nanorod has better performance of water electrolysis and oxygen evolution than transition metal oxide in the prior art, but also the preparation process is simple, fast and efficient, has low production energy consumption, low production cost, environmental protection and no pollution, and is suitable for large-scale industrial production.

The invention discloses a co-precipitation preparation method of a composite oxide denitration catalyst and belongs to the technical field of preparation of nitric oxide reduction catalysts. The method comprises the following steps: in the presence of a solvent, mixing aluminum sulfate, titanium sulfate, ammonium vanadate and sodium metasilicate with at least one of ammonium tungstate, manganese chloride, nickel nitrate, cobalt nitrate and chromic nitrate; then placing an obtained precursor into a muffle furnace, and roasting the precursor to obtain the catalyst. According to the method, the use of TiO2 in a conventional V-W-Ti catalyst is reduced, and the cost is reduced; meanwhile, the specific surface area of the catalyst is increased. The formed catalyst contains two or more of components from Ti, Si, Al, V, W, Cr, Ni, Mn and Co; the denitration activity of the catalyst is favorably improved by the strong cooperative action of each active component and a carrier; the catalyst is applicable to SCR (selective catalytic reduction) denitration reaction at low temperature of 250-500 DEG C.

The invention discloses a method for preparing a ZnFeCr hydrotalcite photocatalyst and relates to preparation methods of catalysts. The method comprises the following preparation steps of (1) preparing a salt solution of ferric nitrate, zinc nitrate and chromic nitrate, wherein the ratio of n(Zn) to n(Fe) to n(Cr) is 1: 1: 1, and the total concentration of metal ions is 1M; (2) preparing a 0.5M solution of sodium hydroxide (NaOH) and sodium carbonate (Na2CO3), wherein the ratio of NaOH to Na2CO3 is 2: 1; (3) simultaneously dropwise adding a metal salt solution and an alkali solution into the salt solution, and controlling the pH value to be 9-10; (4) carrying out hydrothermal crystallization on slurry, obtained after the dropwise adding is ended, for 24 hours at the temperature of 100 DEG C, then, filtrating, washing and drying, thereby obtaining the product. According to the method, the product has good performance in photocatalytic degradation of organic substances; the ZnFeCr hydrotalcite photocatalyst prepared by the method is low in cost, simple and convenient in operation and easy in large-scale production.

The invention discloses a black nanophase ceramics pigment and a preparation method thereof, the method comprises: dissolving ammonium oxalate, ammonium formate, ammonium acetate and ammonium propionate in water and then mixing evenly with chromic nitrate, manganous nitrate, ferric nitrate and cobalt nitrate, heating the mixture at the temperature of 400-500 DEG C, and combusting until no air gives out to obtain the black nanophase ceramics pigment. The invention has simple reaction conditions, and the raw materials such as the nitrates, the ammonium acetate and the like are medicaments with low price and abundant resource; and the invention is benefit to large-scale industrialized production. The prepared black nanophase ceramics pigment has black color, high temperature-resistance, stable performance and good dispersibility.

The invention discloses a method for preparing a chromic oxide-doped carbon nitride (Cr2O3@g-C3N4) composite visible photocatalysis material, and an application of the material. The method comprises the following steps: dissolving chromium nitrate and carbon and nitrogen sources, fully mixing, drying, and roasting the obtained dried mixture in inert atmosphere to obtain the Cr2O3@g-C3N4) composite visible photocatalyst. The catalyst has a good removal effect in visible photocatalysis degradation treatment of a rhodamine B solution, and still has high catalysis activity after the catalyst is reused five times. The composite visible photocatalyst overcomes the disadvantages of low phototransformation efficiency and low activity of a single material, and has the advantages of wide light response range, high visible photocatalytic activity, low cost, and simple and easily controlled preparation process. The photocatalyst can be used in the environmental protection field, and has wide application prospect in visible photocatalytic degradation of organic pollutants in water.

A nano-bimetal carried catalyst NiO-Cr2O3-SiO2 for preparing alcohol by catalytic hydrogenating reaction of aldehyde or ketone is prepared from nickel nitrate and chromium nitrate through adding them to alcohol-acetic acid solution, heating, hydrolyzing to obtain sol, supercritical drying in high-pressure reactor by using alcohol as medium to obtain aerogel, calcining to obtain NiO-CrO3-SiO2, and reducing in H2 to obtain NiO-Cr2O3-SiO2.

The invention discloses a densification formation type preparation method of nickel-based alloy powder. The method is characterized by comprising the following steps: weighting the following components in percentage by mass: 34.3 to 39.4% of nickelous nitrate hexahydrate, 23.9 to 26.9% of chromic nitrate nonahydrate, 1.7 to 2.2% of iron nitrate nonahydrate, 2.5 to 3.1% of ammonium tungstate monohydrate, and 30.7 to 35.4% of oxalic acid; preparing a 300mol solution through nickelous nitrate hexahydrate, chromic nitrate nonahydrate, and ammonium tungstate monohydrate, then heating to reach the temperature of 60 to 85 DEG C, and uniformly stirring; adding 2ml ammonium hydroxide, and stirring for a few minutes; adding iron nitrate nonahydrate and oxalic acid to the solution; maintaining the temperature in a water bath, and uniformly stirring; moving out the solution; naturally cooling to reach the room temperature; filtering and precipitating; drying, filtering and grinding the precipitate; placing the grinded powder into a corundum boat-shaped container; transferring the corundum boat-shaped container into a hydrogenation furnace to reduce at the temperature of 750 DEG C, so as to obtain high-temperature nickel-based alloy powder.

The invention discloses a p type doped CuCro2-based dilute magnetic semiconductor material and a manufacturing method thereof. The CuCro2-based dilute magnetic semiconductor polycrystal block is manufactured, and has a molecular structural formula of CuCr(1-x)TMxO2, wherein, TM is transition metal elements which are Fe, Co, Ni, Mn, and the concentration thereof x is more than or equal to 0 and is less than or equal to 0.2. Cupric acetate, chromic nitrate and transition metal salt are measured according to a mole ratio of cupric, chromic to transition metal of 1: (0.80-1): (0-0.20), the powder is added into distilled water and added with adequate amount of citric acid, and then stirred at room temperature till fully dissolved, thereby obtaining a well mixed solution; then, after processes of parching, grinding, tablet compressing and heat treatment, dilute magnetic semiconductor block material of CuCr(1-x)TMxO2 is manufactured. The invention adopts a sol-gal method and has the advantages of low energy consumption, simple technique and the like. In the invention, all of the components in the solution are well mixed, and the uniformity degree can reach molecular level, so that multi-component homogenous dopant can be manufactured was well as products that are hard to be obtained by traditional solid phase methods. And experiment results have repeatability.

The invention provides a preparation method of a low-leakage current Bi0.92Tb0.08Fe(1-x)CrxO3 film. The method comprises the following steps of: dissolving bismuth nitrate, ferric nitrate, terbium nitrate and chromic nitrate at a molar ratio of 0.97:(1-x):0.08:x into the mixed solution of ethylene glycol monomethyl ether and acetic anhydride to form a mixed solution; adding ethanolamine into the mixed solution to adjust the viscosity and the complexing degree to obtain a stable BiFeO3 precursor liquid; and preparing a Tb and Cr co-doped crystalline BiFeO3 film by a spin-coating method and layer-by-layer annealing technology. The film is a crystalline Bi0.92Tb0.08Fe0.99Cr0.01O3 film, wherein the leakage current density is still kept below 10<-4>A/cm<2> in a 150kv/cm test electric field. According to the method provided by the invention, the requirements on equipment are simple, the experimental conditions are easy to realize, the prepared film has good uniformity, and the leakage current of the film is reduced through the co-doping of Tb and Cr.

The invention relates to a nanometer tungsten carbide powder preparing method. The method includes the following steps that chromic nitrate and ammonium metavanadate are dissolved into deionized water, APT is added, ball milling and slurry forming are carried out, water-soluble PF is then added to continue carrying out ball milling, and then spraying and drying are carried out to obtain composite powder; precursor powder is subjected to ball milling under low temperature with liquid nitrogen as the ball milling medium, and the ball milling product is dried under room temperature and is then placed into a carbon tube furnace and carbonized under hydrogen protection to obtain nanometer tungsten carbide powder. Chromium, vanadium and the PF are added at the beginning of processes, and sizes of WC powder particles can be easily and stably kept at the nanoscale through element internal inhibition in the production process, the external wrapping and isolation function of the PF and liquid nitrogen freezing and ball milling; furthermore, because the WC powder preparation process is simple and easy to control, industrialization production investment is small, production processes are simple and convenient to carry out, production cost is low, and industrial batch production is facilitated.

A preparation method of a titanium-dioxide-based double-layer hollow material includes the following steps: (1) using polystyrene nanospheres with particle size of 180 nm as a template, tetrabutyl titanate as a precursor, to prepare hollow titanium dioxide by calcining; (2) subjecting said hollow titanium dioxide to carboxylation modification to prepare carboxylated titanium dioxide; and (3) dispersing said carboxylated titanium dioxide in ethanol, using chromic nitrate nonahydrate as an assembly agent and trimesic acid as a crosslinking agent to carry out layer-by-layer self-assembly so as to prepare the titanium-dioxide-based double-layer hollow material.

The invention relates to a tempered glass which is prepared from the following raw materials in parts by weight: 6-10 parts of waste glass, 5-10 parts of calcite, 5-7 parts of borax, 3-8 parts of clarifier, 7-10 parts of bauxite, 4-10 parts of titanium dioxide, 3-9 parts of chromic nitrate, 6-11 parts of potassium permanganate, 4-9 parts of chalcanthite, 3-6 parts of barium hydroxide, 4-11 parts of potassium silicate, 5-10 parts of silicon dioxide, 7-9 parts of aluminum oxide and 4-9 parts of bismuth oxide. The tempered glass has the advantages of favorable strength, favorable hardness and low possibility of spontaneous explosion, and can not hurt the human body.

The invention discloses a coke oven flue gas denitration catalyst and a preparation method thereof. The preparation method utilizes ammonium metavanadate as an active precursor, chromium nitrate as an auxiliary agent and oxalic acid and hydrochloric acid as reducing agents, and utilizes phosphoric acid to adjust and control the surface acidity of an active component. The preparation method comprises stirring, water bath heating, drying, calcining to obtain a Cr-doped oxyvanadium phosphate active component, adding the Cr-doped oxyvanadium phosphate active component and anatase TiO2 as a carrier with a specific surface area of greater than or equal to 250 m<2>/g into distilled water according to a ratio, carrying out stirring mixing, and carrying out water bath drying and calcining to obtain the catalyst. The catalyst utilizes phosphoric acid to adjust and control the surface acidity of the catalyst, and utilizes aid chromic nitrate to form an intercalation structure and promote formation of adjacent V<5+> and V<4+>. The catalyst has good low temperature denitration activity and strong SO2 and steam poisoning resistance and is suitable for industrial coke oven flue gas denitrification.

The invention belongs to the technical field of catalysts, and particularly relates to a method for improving the selectivity and the stability of a nickel liquid phase hydrogenation catalyst. The method is suitable for preparing the nickel liquid phase hydrogenation catalyst through co-precipitation. A soluble salt addition agent is supplied to nickel salt in a neutralizing process, soluble salt contains one or several kinds of magnesium nitrate, chromic nitrate, zirconium nitrate, calcium nitrate, lanthanum nitrate and cesium nitrate, and the supplying amount of the soluble salt is 0-0.95 time of the molar weight of the nickel salt. An alkali center adjusting addition agent of the catalyst is added to a filter cake, the alkali center adjusting addition agent and the filter cake are uniformly kneaded, the alkali center adjusting addition agent contains one or several kinds of oxide, hydroxide, metasilicate, carbonate and aluminosilicate of potassium, calcium, sodium, magnesium, zirconium and cesium, and the addition amount of the alkali center adjusting addition agent is 0-0.95 time of the molar weight of precipitated nickel. The method disclosed by the invention can obviously improve the selectivity and the stability of the catalyst.

The invention discloses a process of plating a diamond surface with a composite film. The process comprises the following steps: 1) performing surface treatment on a diamond grinding material; 2) mixing barium acetate with glacial acetic acid to prepare stable BaO sol, soaking the grinding material with the BaO sol, and drying and roasting the grinding material to obtain the diamond grinding material plated with a BaO film; 3) mixing chromic nitrate with glacial acetic acid to prepare stable Cr2O3 sol, soaking the grinding material with Cr2O3, drying and roasting the grinding materials to obtain the diamond grinding material coated with a BaO/Cr2O3 film. According to the process, the surface of the diamond grinding material can be plated with a layer of compact composite film, so that harmful chemical reaction on the diamond grinding material and ceramic bond in a sintering process can be avoided, the wettability of the diamond grinding material and the ceramic bond can also be improved, the holding force on the diamond grinding material by the ceramic bond is increased, and the service life of a grinding tool is prolonged.

The invention relates to an amidoxime group modified MOF material and a preparation method thereof, and belongs to the technical field of materials. The amidoxime group modified MOF material is an MIL-101(Cr) material, and a central atom of the MIL-101(Cr) material which is subjected to coordination modification by amidoxime groups is Cr. The amidoxime group modified MOF material has the advantages of large specific surface area, good water stability, high adsorption efficiency and high adsorption rate; has good selective adsorption performance on uranium, and has good application prospects inthe fields of seawater uranium extraction, radioactive wastewater treatment, environmental remediation and the like. The preparation method is simple in process and good in separation effect, terephthalic acid and chromic nitrate nonahydrate which are relatively cheap reagents are adopted, and the synthesis steps are novel.

The invention discloses a mechanical zinc plating technique which comprises the following steps of: 1) preplating: removing oil and rust and washing; 2) copper plating for priming: plating a thin copper layer on the surface of a workpiece by adopting a chemical copper dipping method, and washing after plating is finished; 3) zinc plating and excessive precipitation: adding zinc powder and dedicated initiator into a roller, rolling for 3-6 minutes; 4) zinc plating and precipitation: adding zinc powder, dedicated initiator, impact media and water into the roller, and rolling for 25-45 minutes; 5) surface passivation: placing the workpiece in passivation solution to form a passivation film; 6) aftertreatment: spin-drying, drying, detecting and accepting. The impact media refers to glass microbeads with the diameter of less than 0.5mm; the passivation solution is chromic nitrate. By adopting the process technology, the energy loss is low, the zinc-plating coating is uniform in thickness, and has good corrosion resistance, wear resistance and stability.

The invention relates to a preparation method and application of a highly active bismuth chromate nano photocatalyst, and belongs to the technical field of nanomaterials. The preparation method comprises the steps: firstly, dissolving bismuth nitrate pentahydrate and chromic nitrate nonahydrate in a mannitol aqueous solution; dropwise adding a saturated sodium carbonate aqueous solution into the solution, and stirring evenly to obtain an emulsion; transferring the emulsion to a hydrothermal reaction kettle, carrying out a hydrothermal reaction, cooling to room temperature, centrifuging, washing and drying to obtain a precursor powder, and calcining the precursor powder, to obtain the bismuth chromate nano photocatalyst. The bismuth chromate nano photocatalyst prepared by the method has thesize in a range of 40-50 nm, and a light absorption band edge can be extended to a red light region; at the same time, the bismuth chromate nano photocatalyst has high-efficiency pollutant photocatalysis degradation and oxygen producing activity in a visible region, the oxygen producing quantum efficiency at 600 nm reaches 1.52%, and the bismuth chromate nano photocatalyst has quite good light stability. The preparation method provided by the method has cheap raw materials, has simple process, is suitable for industrialized mass production, and has good application prospects.

The invention discloses a galvanized steel sheet trivalent chromium passivator concentrated solution. The galvanized steel sheet trivalent chromium passivator concentrated solution is mainly prepared from 5-10 parts of chromic nitrate, 10-20 parts of chromium dihydrogen phosphate, 1-5 parts of inorganic acid, 5-10 parts of sealing agent acidic silica sol, 0.5-2 parts of sodium hypophosphite, 0.5-2 parts of cobalt nitrate, 0.1-2 parts of complexing agent organic acid and 50-65 parts of deionized water. A trivalent chromium passivator can achieve continuous passivation film formation on the surface of an automotive hot-dip galvanized steel sheet, the passivation reaction time is short, the salt spray resisting time of a film is long, and the galvanized steel sheet trivalent chromium passivator concentrated solution is suitable for workpiece treatment through automotive hot-dip galvanized steel sheet dipping and roller coating and especially suitable for the continuous passivation process.