103 results about "Chromium Compounds" patented technology

The present invention relates to a device (1) for the electroplating of a hard chromium layer made of a chromium(III) compound on a surface of a substrate (2), comprising an anode (3) and an electroplating bath (4) into which the substrate (2) acting as a cathode can be introduced, wherein the electroplating bath (4) contains a Cr(III) compound and a carboxyl compound of the formula R-COOH or a salt thereof, where R is a C1-10 alkyl radical, characterized in that the anode (3) is separated from the electroplating bath (4) by a cation-selective membrane (5). The present invention further relates to a method for the electroplating of a hard chromium layer made of a chromium(III) compound on a surface of a substrate (2) in this device (1), and to an article produced by this method comprising a chromium layer.

Catalyst systems suitable for tetramerizing ethylene to form 1-octene may include a catalyst including a chromium compound coordinated with a ligand and a co-catalyst including an organoaluminum compound. The ligand may have a chemical structure according to Formula (1), wherein R1 is a (C3-C20) substituted or unsubstituted hydrocarbyl group; R2, R3, R4, and R5 are independently chosen from (C1-C50) hydrocarbyl groups; and R1 and N are in a cis configuration.

Methods for making a supported chromium catalyst are disclosed, and can comprise contacting a silica-coated alumina containing at least 30 wt. % silica with a chromium-containing compound in a liquid, drying, and calcining in an oxidizing atmosphere at a peak temperature of at least 650° C. to form the supported chromium catalyst. The supported chromium catalyst can contain from 0.01 to 20 wt. % chromium, and typically can have a pore volume from 0.5 to 2 mL / g and a BET surface area from 275 to 550 m2 / g. The supported chromium catalyst subsequently can be used to polymerize olefins to produce, for example, ethylene-based homopolymers and copolymers having high molecular weights and broad molecular weight distributions.

Catalyst compositions containing a pyrrole compound, a chromium compound, an organoaluminum compound, and an aromatic hydrocarbon solvent comprising xylenes or C9 substituted benzenes are disclosed. Related ethylene oligomerization processes utilizing the catalyst compositions to produce oligomer products containing 1-hexene also are described.

Catalyst compositions containing a pyrrole compound, a chromium compound, an organoaluminum compound, and an aromatic hydrocarbon solvent comprising xylenes or C9 substituted benzenes are disclosed. Related ethylene oligomerization processes utilizing the catalyst compositions to produce oligomer products containing 1-hexene also are described.

The invention discloses a vanadium-chromium composite oxide material. The composition of the composite oxide is VCrxMyOz, wherein M is one of Ti, Mo, W, B, Fe, Co, Ni, Cu, Zn, Sb, Bi, alkali metal or alkaline earth metal; x is equal to 0.1-3 and is the atom molar ratio of chromium to vanadium; y is equal to 0-1.5 and is the atom molar ratio of M to vanadium; z is determined according to the valence state of atoms; the composite oxide material is a porous hollow microsphere formed by assembling blocky or flaky nanoparticles, and the diameter of the composite oxide material is 1-100 [mu] m. The invention also discloses a preparation method and application of the material. Vanadium and chromium compounds and compounds of other elements are used as raw materials, amino acid compounds are used as auxiliary reagents, the prepared vanadium and chromium composite oxide can be self-assembled to form a porous hollow micron spherical structure, and the microsphere material is uniform in particle size distribution and large in specific surface area; the vanadium-chromium composite oxide with the structure can be used for preparing aromatic nitrile through ammoxidation reaction of methyl aromatic hydrocarbon, the ammoxidation reaction temperature is low, the reaction activity and the product yield are high, and the selectivity is good.

Disclosed is a grain-oriented electrical steel sheet in which an insulating coating film does not contain a chromium compound but contains a phosphate. When Gaussian fitting is performed on a 31P-NMR spectrum obtained by measuring the insulating coating film by using a nuclear magnetic resonance method in the range of 16 ppm to - 90 ppm, the ratio of the peak area of the Q1 structure to the total peak area is more than 3% but not more than 18%, and the ratio of the Q1 structure is smaller than the ratio of the Q3 structure.

A conversion coating applicator includes a first liner, a hydrogel attached to the first liner, and a second liner removably attached to the hydrogel. The hydrogel includes a trivalent chromium conversion coating solution including a trivalent chromium compound, a zirconate compound, and a dye compound. The conversion coating solution is an aqueous solution.

The invention relates to a method for preparing a catalyst. A process for preparing a catalyst comprising: a) contacting (i) a silica support, (ii) a titanyl compound, (iii) a chromium-containing compound, and (iv) an optional solvent to form a first aqueous mixture comprising a pre-catalyst and a reaction medium comprising from about 1 wt% to about 99 wt% water; b) heat treating the pre-catalyst by heating to a temperature of from about 400 DEG C to about 1000 DEG C for a time of from about 1 minute to about 24 hours to form a catalyst. A method of making a catalyst comprises contacting a hydrated support material comprising silica with a chromium-containing compound to form a first aqueous mixture comprising a chromized support; contacting the first aqueous mixture comprising the chromized support with a solution comprising (i) a solvent and (ii) a titanyl compound to form a second aqueous mixture comprising a pre-catalyst; and heat treating the pre-catalyst to form the catalyst.

This invention relates to the field of chromium slag resource utilization technology, specifically to a method for pre-reduction enhanced oxidation extraction of chromium from chromium slag, comprising: S1, mixing calcium-free roasted chromium slag, carbonaceous reducing agent, and sodium carbonate in a mass ratio of 1:(0.4~0.9):(0.05~0.25) and pressing them into shape to obtain a chromium slag preform; S2, under an inert atmosphere, reducing and roasting the chromium slag preform at 850~1050℃ for 30~150 min to generate sodium chromite, and cooling it to room temperature with the furnace to obtain a pre-reduced chromium slag mixture; S3, under an oxygen-containing atmosphere, oxidizing and roasting the pre-reduced chromium slag mixture at 850~1050℃ for 30~150 min to convert trivalent chromium into water-soluble hexavalent chromium compounds, and air-cooling it to room temperature to obtain a roasting product; S4, stirring and leaching the roasting product in an acidic solution, separating the solid and liquid to obtain a leaching residue and a leachate containing hexavalent chromium. The pre-reduction stage enables lattice reconstruction and micropore optimization, creating favorable reaction conditions for the subsequent oxidation stage, thereby significantly improving the oxidation conversion efficiency of chromium.

Provided is a method for producing monofluoroethane, which enables production of monofluoroethane from ethylene and hydrogen fluoride at a high conversion rate even under mild reaction conditions. This method for producing monofluoroethane comprises reacting ethylene gas with hydrogen fluoride gas in the presence of a catalyst to obtain monofluoroethane. The catalyst contains a chromium compound, which is at least one selected from chromium fluoride and chromium oxyfluoride.

The invention relates to an austenitic stainless steel food-grade pipe welding spot cleaning passivator. The austenitic stainless steel food-grade pipe welding spot cleaning passivator comprises the following components in parts by mass: 0.2-1.2 parts of a complexing agent, 0.5-2.5 parts of a sealing agent, 9.5-18 parts of organic acid, 1-5 parts of an oxidizing agent, 1-5 parts of a coordination agent, 0.2-2 parts of a corrosion inhibitor, 0.4-1.5 parts of an active agent and 64.8-87.2 parts of water. Through compounding of the whole materials, after a stainless steel workpiece is cleaned and passivated, no heavy metal is left on the surface of the workpiece, the corrosion resistance of the surface of the workpiece can be improved, the service life of the workpiece is prolonged, harmful gas, acid mist and toxic substances are not generated in the process of cleaning and passivating the workpiece, and the service life of the workpiece is prolonged. The austenitic stainless steel cleaning and passivating agent is safe and environment-friendly to use, and solves the problems that in the process of cleaning and passivating austenitic stainless steel products by adopting a pickling and passivating method in the market, acid mist is formed, nitrogen dioxide polluting the atmosphere is generated, chromium compounds with high toxicity are generated, and the health of operators is harmed and the environment is polluted.

This invention relates to the field of metallurgical technology, specifically to an ultra-low yield strength ratio, high-phosphorus, atmospheric corrosion-resistant steel and its preparation method. The preparation method includes: placing a cut billet into a slow-cooling pit, with the initial slow-cooling temperature ≥500℃ and the final slow-cooling temperature not lower than 300℃; heating the slow-cooled billet, controlling the billet's exit temperature from the furnace to 1140~1170℃, and the furnace time coefficient to be 10~11 min / cm; employing a two-stage rolling process, with the billet undergoing the first stage of rolling after descaling, and the surface temperature of the rolled piece at the start of the second stage of rolling being T2=(T+1600 / H-1.8H)℃, and the rolled steel plate not being water-cooled; and then placing the rolled steel plate between steel plates at 500~600℃ for at least 48 hours to achieve stacking cooling. This invention utilizes a fine, uniform microstructure and phosphorus and chromium compounds to improve the material's corrosion resistance, meeting the requirements for corrosion resistance and high toughness of steel used in building and engineering structures in coastal atmospheric environments.

The insulating coating of the grain-oriented magnetic steel sheet contains no chromium compound but contains a phosphate, and the content of the phosphate is 0.5% or more and less than 2.0% as measured by the nuclear magnetic resonance method 31 The P-NMR spectrum was subjected to Gaussian fitting in the range of 16 to -90 ppm, and the proportion of the peak area of the structure to the total peak area was more than 0% and 10% or less. 0 The P-NMR spectrum was subjected to Gaussian fitting in the range of 16 to -90 ppm, and the proportion of the peak area of the structure to the total peak area was more than 0% and 10% or less.

A coated substrate comprises a coating extending over at least a portion of the substrate. The coating is obtainable from a coating composition comprising: (a) a polymeric binder; and (b) a feathering reducer comprising carboxylic acid-reactive functional groups. The coated portion of the substrate comprises a pretreatment layer. The pretreatment layer is obtainable from a pretreatment composition comprising a trivalent chromium compound. The present invention also extends to a method of coating the pretreated substrate and coated packaging, such as a metal can.

Methods for making a supported chromium catalyst are disclosed, and can comprise contacting a silica-coated alumina containing at least 30 wt. % silica with a chromium-containing compound in a liquid, drying, and calcining in an oxidizing atmosphere at a peak temperature of at least 650° C. to form the supported chromium catalyst. The supported chromium catalyst can contain from 0.01 to 20 wt. % chromium, and typically can have a pore volume from 0.5 to 2 mL / g and a BET surface area from 275 to 550 m2 / g. The supported chromium catalyst subsequently can be used to polymerize olefins to produce, for example, ethylene-based homopolymers and copolymers having high molecular weights and broad molecular weight distributions.

This grain-oriented electrical steel sheet has an insulating coating that does not contain chromium compounds but contains phosphates, and the insulating coating was measured using a nuclear magnetic resonance method. 31 When P-NMR spectra were fitted with Gaussian waves in the range of 16 to -90 ppm, Q 0 The ratio of the peak area of ​​the structure to the total peak area is more than 0% and 10% or less.

The invention discloses a method for preparing syndiotactic polystyrene through transition metal catalysis. According to the method, an aryl ether-transition metal chromium compound is adopted to catalyze styrene to polymerize so as to prepare syndiotactic polystyrene. According to the preparation method of the compound, an aryl ether compound reacts with tetrahydrofuran chromium trichloride to obtain a chromium complex, then the chromium complex and aluminum alkyl form a catalytic system, bulk polymerization is performed in styrene to obtain syndiotactic polystyrene, and the syndiotactic polystyrene has the advantages of good stereoselectivity and high activity.

This application discloses a method for preparing hydrocortisone acetate, comprising at least the following steps: reacting a raw material containing 11β,17α,21-trihydroxypregn-4-ene-9α-bromo-3,20-dione-21-acetate with a debromination agent to obtain hydrocortisone acetate; wherein the debromination agent is an organophosphorus salt. This application uses an organophosphorus salt as a debromination agent in the preparation of hydrocortisone acetate, avoiding the use of chromium-containing compounds in traditional processes, reducing the environmental costs of the process, and the reaction process is simple and easy to operate, showing good prospects for industrial application.

In this grain-oriented electrical steel sheet, the insulating coating does not contain chromium compounds, the insulating coating has a coating tension of 4.9 MPa or more, and when the potassium intensity of a spectrum obtained by measuring the insulating coating by X-ray fluorescence analysis is defined as P(K) and the sodium intensity of the spectrum is defined as P(Na), the ratio of P(K) to P(Na), P(K) / P(Na), is greater than 13.0 and not greater than 100.

Methods for reducing a concentration of hexavalent chromium within a first aluminum slurry by adding a reducing agent to form a second aluminum slurry are provided. The reducing agent causes a chemical reduction reaction with the hexavalent chromium compound of the first aluminum slurry to form a trivalent chromium compound within the second aluminum slurry such that a first weight ratio of hexavalent chromium to trivalent chromium in the first aluminum slurry is decreased to a second weight ratio of hexavalent chromium to trivalent chromium in the second aluminum slurry, with the second weight ratio being less than the first weight ratio.

The invention relates to a solid catalyst system comprising a first chromium compound, a second chromium compound, a reaction product of an alkyl aluminium compound and a nitrogen containing compound and a silicon oxide support, wherein the first chromium compound is chromium trioxide or a compound convertible to chromium trioxide, the second chromium compound is a slilylchromate compound and the nitrogen containing compound is a cycloalkylamine compound having the general formula: R3—NH2, wherein R3 is selected from C3-C8 cycloalkyl groups.

The invention discloses a chromium-doped garnet broadband near-infrared stress luminescent material as well as a preparation method and application thereof. The preparation method comprises the following steps: respectively weighing a lutetium-containing compound raw material, a gallium-containing compound raw material and a chromium-containing compound raw material according to a general formula Lu3Ga5 (1x) O12: 5xCr < 3 + >, uniformly grinding the raw materials, pre-sintering, cooling to room temperature, grinding and uniformly mixing, calcining at high temperature, cooling to room temperature along with a furnace, and grinding to obtain the chromium-doped garnet broadband near-infrared stress luminescent material. The chromium-doped garnet broadband near-infrared stress luminescent material Lu3Ga5 (1x) O12: 5xCr < 3 + > disclosed by the invention has good stress luminescence self-recovery performance and shows broadband emission in a near-infrared range, and the full width at half maximum (FWHM) is greater than 120 nm. The material has a low-threshold excitation characteristic, can meet the requirement of mechanical imaging in a living body, and can be used for preparing a stress luminescent film suitable for mechanical detection of skeleton joints.

This application relates to the technical field of metal surface treatment and protection. This application discloses a zinc-nickel alloy passivator and a preparation method thereof. A zinc-nickel alloy passivator includes the following raw materials in parts by weight: 50-80 parts of trivalent chromium compound, 10-25 parts of acidic solution, 8-15 parts of hydroxy graphene, 12-20 parts of esterified polytetrafluoroethylene, and 1-3 parts of allylbenzene. The zinc-nickel alloy passivator prepared in this application has excellent comprehensive performance, with excellent corrosion resistance and mechanical strength.

A lead wire for a nonaqueous electrolyte battery according to the present disclosure is provided with: a conductor; and one or more layers of insulating films that cover at least a portion of the outer peripheral surface of the conductor, the conductor having a conductor coating that covers at least a portion of the surface, the conductor coating containing a metal element and a trivalent chromium compound containing chromium hydroxide, the ratio of the number of chromium atoms contained in the chromium hydroxide to the number of chromium atoms contained in the trivalent chromium compound in the outermost surface of the conductor coating film is 0.40-0.85, and the insulating film has an innermost layer laminated on the surface of the conductor coating film. The innermost layer is mainly composed of a resin component containing maleic anhydride-modified polypropylene, and the acid modification rate of the resin component is 0.02 mass% or more and 0.50 mass% or less.

The invention provides a preparation method and application of a Cr-series catalyst for propane dehydrogenation, and the preparation method comprises the following steps: (1) mixing pseudo-boehmite, titanium oxide and sesbania gum powder to obtain mixed powder; (2) mixing a first auxiliary agent and a nitric acid solution, stirring and dissolving to obtain a first auxiliary agent solution; (3) in a stirring state, dropwise adding the first auxiliary agent solution into the mixed powder, after dropwise adding, performing kneading and strip extrusion, and then performing vacuum drying and roasting to obtain a carrier; and (4) mixing a chromium-containing compound, a second auxiliary agent and water to obtain an impregnation liquid, adding the carrier into the impregnation liquid for impregnation adsorption, and then performing vacuum drying and roasting to obtain the catalyst, the first auxiliary agent is at least one of zinc nitrate, zirconium oxychloride, zirconium nitrate, urea and ammonium chloride; the second auxiliary agent is at least one of cerous nitrate, manganous nitrate, lanthanum nitrate and aluminum nitrate. The catalyst is excellent in performance, good in regeneration performance and high in propylene product yield.

The present invention discloses a surface treatment method for an aluminum foil current collector and a battery electrode. The surface treatment method comprises the following steps: S1, preparing a first treatment liquid of phosphoric acid or nitric acid with a mass concentration of 1 to 10%, immersing the aluminum foil in the first treatment liquid, and ultrasonically cleaning the aluminum foil for 0.1 to 10 minutes; S2, adding a chromium-containing compound, a polyacrylic resin, and a fluoride to deionized water to prepare a second treatment liquid, wherein the chromium-containing compound is chromium phosphate or chromium nitrate, and the fluoride is one or more of chromium fluoride, magnesium fluoride, ammonium fluoride, and hydrofluoric acid; rolling the second treatment liquid onto the surface of the aluminum foil obtained in step S1, and drying the liquid to obtain the aluminum foil current collector. The first and second treatment liquids of the present invention have simple formulations and a simple process. The prepared aluminum foil can achieve a dyne value of 55 or above, significantly improves corrosion resistance in electrolyte, and enhances adhesion to the carbon coating layer.

To provide a composition for surface treatment capable of imparting flat sheet corrosion resistance, worked part corrosion resistance, pitting corrosion resistance, blackening resistance, pipe making oil infiltration resistance and alkali resistance to a steel sheet and improving foreign matter defects, and to provide a steel sheet using the same.SOLUTION: The surface treatment composition includes a trivalent chromium compound; an adhesion improving agent including a silane compound; an acidity controller including an acid; a cross-linking agent including a silicate compound; a vanadium-based pitting corrosion improving agent; a polymer resin; and a solvent.SELECTED DRAWING: Figure 1

The present application relates to a kind of preparation method of isophthalic acid, belong to organic synthesis and fine chemical technology field.The method uses m-xylene as raw material, air as oxidant, under the condition of no additional solvent, using the catalyst containing cobalt, manganese, chromium compound carries out catalytic oxidation reaction.After reaction, it is obtained isophthalic acid by cooling, filtering, washing and drying.The present application uses halogen-free cobalt-manganese-chromium catalyst system and cancels solvent, fundamentally solves the problem of serious corrosion of traditional process equipment, large pollution of acid-containing wastewater containing bromine, while having the advantages of mild condition, simple process, high atom economy and material closed loop can be realized, provides a cleaner, safer, more economical isophthalic acid production path.