33 results about "Magnesium-aluminum oxide" patented technology

An electrically conducting cermet comprises at least one transition metal element dispersed in a matrix of at least one refractory oxide selected from the group consisting of yttria, alumina, garnet, magnesium aluminum oxide, and combinations; wherein an amount of the at least one transition metal element is less than 15 volume percent of the total volume of the cermet. A device comprises the aforementioned electrically conducting cermet.

Methods for improved manufacture of green biodiesel focus on the selection and use of one or more solid metallic oxide base catalyst(s) selected from the group consisting of calcium oxide (CaO), calcium aluminum oxide (CaO—Al₂O₃), calcium titanate (CaTiO₃), barium titanate (BaTiO₃), magnesium aluminum oxide (MgO—Al₂O₃), zinc oxide (ZnO), copper (II) oxide (CuO), nickel oxide (NiO), manganese oxide (MnO), titanium oxide (TiO), vanadium oxide (VO), cobalt oxide (CoO), iron oxide (FeO), chromite (FeCr₂O₄), hydrotalcite (Mg₆Al₂(CO₃)(OH)₁₆.4(H₂O), magnetite (Fe₃O₄), magnesium silicate and calcium silicate.

A catalyst for selectively hydrogenating and dediolefinating for light hydrocarbon fractions, comprises 0.05í½1.0 wgtúÑ Pd as the active component and the carrier of magnesium aluminum oxide solid solution. In the magnesium aluminum oxide, the mol ration of Mg/Al is 1.0í½12.0. the catalyst also contains auxiliary agents selecting from Co, Mo, Ni and Wu. The catalyst is suitable for selectively hydrogenating and dediolefinating for light C4-C6 hydrocarbon fractions.

The invention discloses an electric heating tube manufacturing process, which relates to the technical field of electric heating tube manufacturing. The process comprises steps: decontamination and impurity removal are carried out; an electric heating wire is manufactured; resistance of the electric heating wire is measured; a conductive rod is riveted on the electric heating wire; the electric heating wire penetrates through a seamless steel tube, and filling of G3 high-temperature magnesium aluminum oxide powder is carried out; in a condition of 3000 to 3500V/mit, high voltage detection is carried out; tube narrowing is carried out, and the diameter of the seamless steel tube is narrowed to 12mm from 14mm; the resistance of the electric heating wire is measured again, and requirements are reached; second-time high voltage test is carried out in a condition no lower than 2800V/mit; drying and annealing are carried out; and test is carried out according to drawing requirements, and after qualification, a tube sealing nozzle is sealed with silicone oil. The electric heating tube manufactured by the above process has the advantages of high voltage resistance, long service life and hard damage.

The invention provides a resin composition, a prepreg, a laminated board, a preparation method of the prepreg, a preparation method of the laminated board and application of the laminated board. The resin composition is prepared from the following components in parts by weight: 20-40 parts of a hydrocarbon resin containing C-C unsaturated bonds, 10-40 parts of a heat-conducting filler, 1-3 parts of a silane coupling agent and 0.1-10 parts of an initiator, wherein the heat-conducting filler is selected from one, two or more of silicon dioxide, silicon carbide, aluminum oxide, aluminum nitride,magnesium aluminum oxide, boron nitride or titanium dioxide. According to the invention, the prepreg and the laminated board are prepared from the resin composition; and the prepreg and the laminatedboard have high thermal conductivity and low dielectric loss, can be applied to a circuit board, and are particularly suitable for being applied to a circuit board of high-frequency 5G communication equipment.

The present invention provides a method for preparing a heterogeneous catalyst in the presence of a templating agent, wherein the heterogeneous catalyst is used for preparing isophorone through acetone condensation, and is a modified composite oxide (MgO-Al2O3-M<x+>Ox/2) based on a magnesium aluminum oxide. The preparation method comprises: weighing a certain amount of a mixed salt, dissolving ina certain amount of water, adding a certain amount of a templating agent, adding a certain amount of a precipitating agent to the mixed salt solution in a dropwise manner at a certain temperature, aging, filtering, washing, drying, and calcining to obtain the catalyst. Compared with the catalyst in the prior art, the catalyst of the present invention has advantages of simple preparation method, low price, low bulk density, high activity, high selectivity and good stability. According to the present invention, in the reaction for preparing isophorone through acetone condensation, the reaction temperature is 250-300 DEG C, the mass space velocity of acetone is 1-8 h<-1> under normal pressure, the conversion rate of acetone is up to 45%, the isophorone selectivity is 75%, the mesityl oxide and isophorone selectivity is 90%, and the technology is suitable for the industrial production of isophorone.

The invention discloses a calcium silicate composite fireproof door core plate, and belongs to the field of fireproof door core plates. The calcium silicate composite fireproof door core plate is characterized in that: a calcium silicate plate is compounded between two layers of inorganic soluble ceramic fiber plates, and a magnesium aluminum oxide cement layer is arranged between the inorganic soluble ceramic fiber plate and the calcium silicate plate. The fireproof door core plate body has a sandwiched composite structure formed by sticking the moisture-proof inorganic soluble ceramic fiber plate, the calcium silicate plate and the inorganic soluble ceramic fiber plate. The fireproof door core plate with the structure is characterized in that: because of the compound structure of the moisture-proof calcium silicate plate and the inorganic soluble ceramic fiber plates, the fireproof door core plate has the advantages of low volume density, high continuous high-temperature fireproof performance, energy conservation, consumption reduction, excellent sound insulation performance, high strength, high toughness, accurate size, and the like and can be easily processed; the steel plate can be easily embossed; and because all the materials are subjected to moisture-proof treatment, the fireproof door core plate has high durability.

The invention relates to a supporter for a C10-C13 long-chain normal paraffin hydrocarbon dehydrogenation catalyst, which is prepared by a co-impregnation preparation method by using ammonia water as a precipitating agent. The supporter is a magnesium aluminum oxide composite. The catalyst prepared from the supporter by a vacuum impregnation method comprises the following active components: 0.2-0.5% of Pt and 0.4-4.0% of Sn. The catalyst is mainly used for preparing monoolefines by dehydrogenating C10-C13 long-chain normal paraffin hydrocarbons. Compared with the catalyst prepared from the aluminum oxide supporter by the same method, the catalyst prepared from the magnesium aluminum oxide composite supporter has obviously higher reaction activity and stability; and compared with the commercial catalyst NDC-8, the catalyst prepared from the magnesium aluminum oxide composite supporter also has higher activity and stability.

The invention relates to an aluminum alloy hardened plating layer treatment process. The process includes the steps of: 1, polishing and cleaning the surface of an aluminum alloy workpiece, then daubing a base agent on the surface, wherein the base agent comprises 5-10 parts of aluminum chloride, 2-6 parts of magnesium chloride and 50-80 parts of a rosin solution; 2, heating the aluminum alloy surface obtained in step 1 at 300-400DEG C for 1h, and adding oxygen with an concentration of 60-70%; and 3, introducing sulfur oxide gas to the aluminum alloy piece obtained by step 2 under an oxygen insulation condition, and carrying out heating at 800-1000DEG C for 30h. According to the invention, by means of an accelerated oxidation process, a compact mixed layer of magnesium aluminum oxide and ferroferric oxide can be obtained on the aluminum alloy surface, compared with the aluminum oxide layer of common aluminum alloy, the surface has higher density, and the surface friction is also smaller.

The invention discloses a preparation method of propylene glycol monoalkyl ether. Propylene oxide and alcohol are used as raw materials and react under the catalysis of a modified magnetic solid basecatalyst to prepare the propylene glycol monoalkyl ether. The catalyst is obtained by taking nickel ferrite as a magnetic core, magnesium-aluminum oxide as a carrier and cesium as an active componentthrough transition metal modification. The method improves the reaction activity and selectivity, and alleviates the operation conditions; and the catalyst is long in service lifetime, easy to recoverand regenerate and low in production product, overcomes various defects in the prior art, and can be used for industrial production.

The invention discloses a nozzle coating for continuous casting of rare earth steel and a preparation method of the nozzle coating, belongs to the technical field of refractory materials, and solves the problem that a nozzle is nodulated and blocked in the current continuous casting process of the rare earth steel. The invention relates to a nozzle coating for continuous casting of rare earth steel, which comprises the following components: magnesium aluminum oxide and rare earth oxide, and the mass ratio of the magnesium aluminum oxide to the rare earth oxide is 83.3-94: 1.98-10; the magnesium-aluminum oxide is MgO.Al2O3 or takes MgO.Al2O3 as a main component, and contains a trace amount of MgO; the rare earth steel is steel containing rare earth cerium and/or lanthanum, and the type of the rare earth oxide is the same as that of rare earth in the rare earth steel. The nozzle coating can reduce nodulation of the submersed nozzle in the rare earth steel continuous casting process, so that the replacement frequency of the submersed nozzle is averagely reduced by more than 50%, and smooth operation of rare earth steel continuous casting is guaranteed.

The invention discloses a preparation method of high-thermal-conductivity insulating graphene for a high polymer material and graphene. The method comprises the following steps: taking graphene oxide as a raw material to obtain uniformly dispersed graphene oxide slurry; the preparation method comprises the following steps: dissolving soluble aluminum salt, magnesium salt and alkali in deionized water to obtain an acid-base solution, and stirring and mixing a silane coupling agent, deionized water, acetic acid and ethanol to obtain a silane coupling agent reaction solution; pumping the graphene oxide slurry into an acid and alkali resistant reaction kettle, wherein the reaction kettle has stirring and jacket temperature control functions; an alkali solution is pumped in until the pH value is 6-9, and the temperature in the reaction kettle is 20-40 DEG C; the preparation method comprises the following steps: grinding and crushing sintered aluminum oxide/magnesium aluminate spinel/magnesium oxide coated graphene powder by adopting a heatable vertical stirring mill until the particle size is equal to the flake diameter of graphene, spraying a silane coupling agent reaction solution into the stirring mill, and continuously carrying out ball milling until the silane coupling agent reaction solution uniformly coats the surface of the powder, so as to obtain the silane coupling agent coated graphene powder. The product aluminum magnesium oxide and coupling agent modified graphene is obtained.

The invention discloses a cable processing technology which comprises the following steps: preparing a conductor petal; preparing a conductor core; preparing an anti-interference layer: selecting raw materials including polyethylene, tinned broken copper wires, calcium stearate, conductive carbon black, nano aluminum oxide, magnesium, an adhesive, an antioxidant, methyl silicone oil, silicon dioxide, butylated hydroxytoluene and a thermal resistance mixture, and adding the polyethylene, the calcium stearate, the nano aluminum oxide, the magnesium, the silicon dioxide and the butylated hydroxytoluene into a mixing stirrer for stirring; after completion, tinned broken copper wires, conductive carbon black and a thermal resistance mixture are added into the mixing stirrer, the mixture is continuously added into the mixing stirrer, stirring is performed again, an adhesive, an antioxidant and methyl silicone oil are slowly added into the mixing stirrer in the stirring process, an anti-interference mixture is obtained, and the anti-interference mixture and a conductor core are both added into a plastic extruding machine; and preparing an outer protective layer. The preparation process is simple, and the prepared cable is resistant to magnetic interference, good in flame retardant effect and high in tensile property.

The invention relates to a preparation process of 2,3,3,3-tetrafluoropropionic acid. According to the method, the 2,3,3,3-tetrafluoropropionic acid is prepared by taking waste liquor containing N,N-diethyl-2,3,3,3-tetrafluoropropylamide as a raw material and taking beryllium-doped magnesium aluminum oxide solid super base as a catalyst under a hydrolysis condition. The molar yield is 99 percent ormore.

The invention provides a tungsten oxide catalyst loaded by a tin-magnesium-aluminum composite oxide carrier and a preparation method of the catalyst. The mass percent of the components in the catalystis as the follows: Al2O3:MgO:SnO2:WO3=(6-9):(1-4):(2-5):(1-5). According to the method disclosed by the invention, activity and the service life of the catalyst are improved through a method for loading tungsten oxide by the tin-magnesium-aluminum oxide carrier, so that preparation cost of the catalyst is reduced, and the problem that use cost of a common composite oxide catalyst is too high, activity and the service life are low, and the yield of epsilon-caprolactone is low in a process of preparing epsilon-caprolactone by indirectly oxidizing cyclohexanone by hydrogen peroxide is solved.