97 results about "Alumina composite" patented technology

The invention belongs to the technical field of ceramic materials, and particularly discloses whisker toughened zirconium oxide-aluminum oxide composite ceramic and an additive manufacturing method thereof, the composite ceramic comprises the following components by mass: 94 parts of zirconium oxide toughened aluminum oxide ceramic and 5 parts of silicon carbide whisker; the zirconium oxide toughened aluminum oxide ceramic is prepared from the following components in parts by mass: 76 parts of aluminum oxide and 24 parts of zirconium oxide, and 3mol% of yttrium oxide is added into the zirconium oxide. According to the whisker toughened zirconium oxide-aluminum oxide composite ceramic and the additive manufacturing method thereof, the preparation method has unique design of components and process, and the preparation of a high-density and high-performance ceramic-based composite material part based on a fused deposition modeling technology is successfully realized. Further, the prepared silicon carbide whisker toughened zirconium oxide-aluminum oxide-based composite ceramic has relatively high density and excellent obdurability.

The invention discloses a high-bending-resistance and low-dielectric-loss LTCC substrate preparation method and an LTCC substrate, and the method comprises the steps: mixing inorganic powder, an organic system and a solvent through ball milling, dissolving and stirring, and preparing a green ceramic chip through a tape casting technology; carrying out lamination, warm isostatic pressing, cutting, glue discharging and sintering on the green ceramic chip to obtain the LTCC substrate; the inorganic powder comprises sodium borosilicate glass, aluminum oxide and mullite whiskers. According to the invention, the sodium borosilicate glass is used as a glass phase, the mullite whisker and the alumina powder are used as ceramic phases, and the excellent mechanical properties and extremely low dielectric loss of the mullite whisker are utilized to modify the sodium borosilicate glass-alumina composite material. The problems that an existing sodium borosilicate glass-aluminum oxide LTCC composite material is low in bending strength and high in dielectric loss are solved.

The present application relates to the field of high-speed spraying technology, in particular to a supersonic flame spraying process for steam turbine blades. The present application overcomes the problems of insufficient coating bonding strength and poor corrosion resistance of the supersonic flame spraying. The present application uses nickel-coated alumina composite sand for sandblasting pretreatment of the blades to achieve micro-implantation of active nickel; adjusts the ratio of NiCr and Cr3C2-NiCr powders by using double powder feeders to build a gradient structure coating with continuous component change; uses a modified sealing agent containing nano-alumina for vacuum impregnation sealing; and finally obtains finished blades through graded vacuum diffusion annealing. Through surface nickel implantation, gradient structure design and diffusion annealing, the present application realizes metallurgical bonding and thermal stress matching between the coating and the substrate, greatly improving the bonding strength; at the same time, the in-situ ceramicization reaction of the sealing agent eliminates micro-pores, significantly enhancing the corrosion resistance of the coating.

This invention relates to the field of composite current collector base film materials, and discloses a heat-resistant and aging-resistant composite current collector base film and its preparation process. It is prepared by melt extrusion and stretching of the following raw materials in parts by weight: 100 parts PET resin, 12-25 parts multi-component composite reinforcing filler, and 0.5-3 parts lubricant. The multi-component composite reinforcing filler is prepared through the following steps: S1, halloysite nanotubes are composited with aminated mesoporous alumina, modified, and then loaded with an antioxidant to obtain functionalized halloysite nanotube-alumina composite particles; S2, magnesium oxide is deposited on graphene oxide, and modified to obtain a modified graphene oxide-magnesium oxide composite; S3, after blending, polymer grafting is performed to obtain the multi-component composite reinforcing filler. This invention, through the multi-component composite reinforcing filler in PET resin, can comprehensively improve the heat resistance, aging resistance, and bonding strength between the base film and the metal layer of the PET resin-based composite current collector base film.

The invention provides a diesel oil hydro-upgrading catalyst and a preparation method thereof. The catalyst prepared by the method is spherical and is composed of a molecular sieve, an active metal-amorphous silicon-aluminum compound and an active metal-aluminum oxide compound, the molecular sieve is a core, the active metal-amorphous silicon-aluminum compound is a middle layer, the active metal-aluminum oxide compound is a shell layer, and the thicknesses of the molecular sieve, the active metal-amorphous silicon-aluminum compound and the active metal-aluminum oxide compound can be flexibly adjusted. The catalyst has an open pore channel structure in stepped pore distribution, the pore diameter is gradually increased from inside to outside, the acidity is gradually reduced from inside to outside, the active metal content is gradually increased from inside to outside, the catalyst and the molecular sieve are distributed in a partitioned manner, and the change of the pore diameter, the acidity and the active metal content has the characteristics of coherence and small span. The catalyst is especially suitable for the hydrogenation modification process of straight-run diesel oil, the hydrogenation capacity and the ring opening capacity of the catalyst are highly matched, the yield of modified diesel oil is high, the BMCI is low, and the maximum production of high-quality ethylene cracking raw materials from straight-run diesel oil can be realized.

The invention discloses a high-temperature-resistant coating for towers and a preparation method of the high-temperature-resistant coating, and belongs to the technical field of coatings. Flame-retardant silane monomers containing pyrimidyl and nitrile group structures are introduced and condensed and hydrolyzed to form modified organic silicon resin, and the high-temperature-resistant coating for the towers is prepared by utilizing the high thermal stability of pyrimidine rings and the charring tendency of nitrile groups in the heating process. According to the present invention, by introducing the silane, the resin matrix can form the stable heat-resistant skeleton so as to significantly improve the structure retention ability and the thermal oxidation resistance of the coating at the high temperature, and by introducing the silanized fluorine-containing phosphate, the nano-silica and the nano-alumina composite filler, the inorganic phase can construct the compact barrier network in the coating so as to improve the thermal oxidation resistance of the coating; the heat resistance, flame retardance and corrosion resistance are further enhanced, the prepared coating shows excellent adhesive force, barrier property and long-term high-temperature stability in a high-temperature, humid and corrosive medium environment, the service life of a high-temperature tower in a complex environment can be effectively prolonged, and the coating has a good engineering application prospect.

The invention discloses a carbon-aluminum oxide composite carrier and a preparation method thereof. The carbon-aluminum oxide composite carrier is spherical particles and comprises a carbon shell and an aluminum oxide core, the carbon shell contains rich macroporous channels, the content of C is 10-25 wt%, the content of Al2O3 is 75-90 wt%, the specific surface area is 250-480 m < 2 > / g, and the pore volume is 0.8-1.3 mL / g. The preparation method comprises the following steps: (1) uniformly mixing flour and inorganic alkali, and grinding to obtain alkali modified flour; (2) putting the aluminum oxide precursor into a turntable forming machine, and carrying out ball rolling forming to obtain aluminum oxide precursor microspheres; (3) putting the alkali-modified flour and the alumina precursor microspheres into a turntable forming machine, and rolling and forming to obtain a carbon-alumina composite carrier precursor; and (4) carrying out heat treatment on the carbon-aluminum oxide composite carrier precursor in a closed container, and drying and roasting the treated material to obtain the carbon-aluminum oxide composite carrier. The carbon-alumina composite carrier provided by the invention is suitable for being used as a catalyst carrier and an adsorption-separation material, and is especially suitable for the field of heavy residual oil hydrotreatment.

This invention discloses a fluidized bed hydrotreating catalyst, its preparation method, and its application. The hydrotreating catalyst includes a hydrotreating active metal component, a support, and optional auxiliary phosphorus. The support is a carbon-containing alumina composite support. The preparation method includes the following steps: (1) spheroidizing a first pseudoboehmite powder to obtain a first support precursor; (2) treating an aqueous solution of the first support precursor, an additive, and an organic polymer B to obtain a second support precursor; (3) treating the second support precursor, the second pseudoboehmite powder, and an acidic solution to obtain a third support precursor; (4) subjecting the third support precursor to low-temperature heat treatment to obtain a fourth support precursor; (5) mixing the fourth support precursor with an auxiliary solution, drying, and calcining to obtain an auxiliary-modified carbon-containing alumina composite support; (6) introducing a hydrotreating active metal component onto the composite support, followed by drying and calcining to obtain the fluidized bed hydrotreating catalyst.

The present application belongs to the technical field of special composite material preparation, and relates to a kind of fiber reinforced metal matrix composite material and its atmospheric pressure preparation process.Metal alloy matrix is added into induction furnace to heat to fully melt, and then cooled to solid-liquid mixed state;Alumina fiber surface is plated after cutting, put into induction furnace, and mechanically stirred to fully mix evenly;Temperature is raised and kept for matrix alloying, poured into mold, compacted and programmed cooling operation;Secondary temperature is raised and kept for subsequent aging treatment, and then naturally cooled to room temperature to obtain the product.The technical difficulties of large equipment required for preparing alumina composite material can be solved, the grain is refined, and the strength and density of the composite material are improved.The fiber content is controllable, and the composite configuration of particles and short, medium and long fibers is realized.The process is simple, the preparation cost is low, and special atmosphere protection is not required.

The invention relates to the technical field of catalysts, in particular to a cerium oxide-aluminum oxide composite material as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing cerous nitrate, aluminum nitrate and water to obtain a mixed solution; the molar ratio of the cerium nitrate to the aluminum nitrate is 10: 1; and adding ammonia water into the mixed solution to carry out coprecipitation reaction, carrying out solid-liquid separation to obtain precursor powder, and calcining to obtain the cerium oxide-aluminum oxide composite material. By selecting raw materials and optimizing preparation steps and process parameters, the prepared catalyst has high activity. The high dispersion of Al2O3 on the carrier CeO2 and a proper crystal structure provide more effective active sites, so that the adsorption and conversion of reactant molecules are promoted. The cerium oxide-aluminum oxide composite material provided by the invention can be used as a catalyst to synergistically purify NOx and CVOCs, and has a matched reaction temperature window for oxidation of CVOCs and reduction of NOx.

The invention discloses a high-temperature-resistant piezoelectric micro-electro-mechanical transducer, which comprises a shell made of silicon carbide ceramic; the PMUT area array is positioned in the shell; the support is made of an aluminum oxide ceramic material and is arranged between the shell and the PMUT area array; the sound matching layer is coated on the PMUT area array and is made of an aluminum oxide-PDMS (Polydimethylsiloxane) composite material; and the NBPSC fireproof coating layer is coated on the sound matching layer. The transducer can resist high temperature of 1500 DEG C or above, and the problem that the performance of an existing PMUT is limited in a high-temperature environment is solved.

This invention provides a method and system for the directional loading of active components in a dimethyl carbonate synthesis catalyst, relating to the field of catalyst technology. The method includes pretreatment and surface modification of a porous silica-alumina composite oxide support; selective loading of cerium oxide nanoparticles onto the inner walls of the modified support pores using atomic layer deposition (ALD); directional bonding of palladium ions to the cerium oxide nanoparticles via microwave irradiation; and finally, reduction in a nitrogen atmosphere to obtain the catalyst. This method enables the directional loading of active components, improving the catalyst's activity and selectivity, and thus enhancing the synthesis efficiency of dimethyl carbonate.

The preparation method comprises the following steps: uniformly mixing a molecular sieve with a carbonyl sulfide hydrolysis catalyst, then adding a dispersing solvent, mixing by adopting a liquid-assisted grinding method, and then drying and calcining to obtain the carbonyl sulfide low-temperature chlorine-hydrolysis-resistant molecular sieve / alumina composite catalyst. The molecular sieve / alumina composite catalyst for carbonyl sulfide low temperature and chlorine hydrolysis resistance is obtained. The carbonyl sulfide hydrolysis catalyst is used as an active component of carbonyl sulfide hydrolysis reaction, and the molecular sieve aid is used for adsorbing, regulating and controlling a slow-release water-gas component and an HCl poisoning component, so that the low-temperature activity and chlorine poisoning resistance of the active component are improved; the composite catalyst provided by the invention reduces the reaction temperature for catalyzing hydrolysis of carbonyl sulfide, improves the chlorine poisoning resistance, realizes low-temperature, low-energy-consumption and stable removal of carbonyl sulfide in blast furnace gas, and solves the technical problem of deep desulfurization of blast furnace gas in the prior art.

This invention provides an alumina inert coating for silicon-based ceramic cores. The alumina inert coating is made from the following raw materials in parts by weight: 20-35 parts alumina composite ceramic powder and 65-80 parts coating additives; the alumina composite ceramic powder is made from the following raw materials in parts by weight: 86-100 parts alumina powder, 0.1-4 parts mineralization modifier, and 0.1-10 parts modified sintering aid. The alumina inert coating of this invention uses alumina as the coating material matrix, effectively isolating the silicon-based ceramic core matrix from the high-temperature alloy during the casting process. This significantly prevents interfacial reactions between the alumina and the high-temperature alloy during ceramic core casting, contributing to the dimensional accuracy of hollow turbine blades. The introduction of boron carbide, which is oxidized during high-temperature sintering to generate boron oxide, promotes the sintering process, making the material denser, reducing porosity, and further improving the strength and toughness of the ceramic core.

The application discloses an energy-saving halogen-free cable for intelligent building fire prevention, and relates to the technical field of building fire-fighting power supply and distribution cables. The cable comprises a cable core composed of one or more conductors, the conductors adopt copper alloy with electric conductivity of 60%IACS-90%IACS, and the surface is coated with a nano ceramic alumina composite coating; the conductors are coated with a halogen-free flame-retardant cross-linked polyolefin insulation layer, the insulation layer is provided with a filling layer in which phase change energy storage microcapsules are dispersed, the filling layer is wrapped with a ceramicized silicone rubber composite tape to form a heat insulation and fire resistance layer, the heat insulation and fire resistance layer is coated with a corrugated aluminum alloy interlocking armor layer, and the outermost layer is extruded with a thermoplastic elastomer outer sheath. The cable can slow down the heating of the conductors, reduce the thermal shock peak of the cable core, improve the line integrity and power supply retention capacity under fire conditions, and meet the requirements of low-smoke halogen-free, mechanical protection and bending laying, and is suitable for intelligent building fire-fighting linkage, emergency lighting, security monitoring and building control line systems.

The invention discloses an alumina composite zirconia ceramic ball and a preparation method thereof, and relates to the technical field of ceramics. The preparation method of the alumina composite zirconia ceramic ball comprises the following steps: mixing zirconia, alumina, cerium oxide, yttrium oxide and sodium oxide according to a specific ratio, and carrying out wet grinding, spray granulation, rolling molding, sintering and other processes to prepare the alumina composite zirconia ceramic ball. Compared with the prior art, the alumina composite zirconia ceramic ball prepared by the invention improves the hardness of a zirconia grinding medium, keeps good wear resistance, has excellent aging resistance, and solves the problems of high grinding wear, high impurity content introduction and short service life of the existing high-hardness material to a certain extent.

The invention relates to the technical field of detergents, and provides a surfactant powder, a solid detergent, a washing consumable and a preparation method and application thereof, the surfactant powder comprises a carrier, and the carrier is mainly one or a combination of more than two of 4A zeolite, mesoporous ZSM-5 zeolite and a zeolite-alumina composite material; the liquid surface active agent is adsorbed on the carrier; the zeolite-aluminum oxide composite material is a composite material formed by coating mesoporous ZSM-5 zeolite particles with gamma aluminum oxide sol and then sintering. The surfactant powder still keeps powder properties in a room-temperature environment and under the condition of high content of a liquid surfactant, and the surface of the powder is kept dry, so that the problem that the addition amount of a traditional liquid surfactant in solid-form dishwashing consumables such as dishwashing powder and the like cannot be too high is effectively solved; and the stability and the cleaning capability of the dish washing consumables are improved.

The invention provides a humus-aluminum oxide composite material, application thereof and a soda alkali soil improvement method, and relates to the technical field of saline-alkali soil improvement. The invention provides a humus-aluminum oxide composite material. The humus-aluminum oxide composite material comprises natural humus and aluminum oxide. The natural humus material and the aluminum oxide adopted by the invention respectively show obvious advantages in the aspects of improving the organic matter content, the structural stability, the salinity regulation and control, the microbial ecology and the like of the soil. The two components are jointly applied to the saline-alkali soil, the physical-chemical-biological improvement effects of the two components can be synergistically exerted, the soil quality and the ecological function are improved, and a new path and theoretical support are provided for efficient and sustainable utilization of the saline-alkali soil.

The invention discloses a double-sided wave-absorbing continuous alumina fiber reinforced alumina composite material compatible with infrared stealth and a preparation method thereof, and belongs to the technical field of stealth materials. According to the double-sided wave-absorbing continuous alumina fiber reinforced alumina composite material compatible with infrared stealth, on the premise that the strength of the continuous fiber alumina fiber reinforced alumina composite material is guaranteed, the relative dielectric constant of a composite material body is reduced by controlling the porosity (the density of the composite material); and the frequency selective surface layer and the resistance type metamaterial layer are arranged, so that the thin double-sided wave-absorbing continuous fiber alumina fiber reinforced alumina composite material is obtained, and meanwhile, the material has relatively low infrared emissivity.

The invention discloses a fluororubber composition. The invention discloses a preparation method of the fluororubber composition, which comprises the following steps: mixing and stirring hollow activated graphene, vinyl-terminated polydimethylsiloxane, alpha, omega-dihydroxy polydimethylsiloxane, an addition reaction catalyst and a plasticizer, and then adding fluororubber for plastication to obtain the fluororubber compound; the preparation method comprises the following steps: fully stirring vinyl-terminated polydimethylsiloxane, expanded graphite particles, alumina powder, a cross-linking agent and an addition reaction inhibitor to obtain an expanded graphite-alumina compound; mixing the fluororubber compound, the expanded graphite-aluminum oxide compound, calcium hydroxide, active magnesium oxide, palm wax, hexafluorobisphenol A and benzyltriphenyl phosphorus chloride, carrying out thin-passing blanking, carrying out compression molding, standing, vulcanizing at 150-170 DEG C for 5-12 minutes, and cooling to room temperature to obtain the fluororubber composition.

This invention discloses a catalyst for the processing and conversion of waste plastics and its preparation method. The preparation method includes the following steps: (1) adding a molecular sieve to a mixed solution containing a Group VIII metal compound and a Group VIB metal compound, separating and drying the sieve after impregnation to obtain a pretreated molecular sieve; (2) preparing a silica-alumina composite sol; (3) introducing the pretreated molecular sieve obtained in step (1) into the silica-alumina composite sol obtained in step (2) to prepare a catalytic precursor; (4) introducing the catalytic precursor obtained in step (3) into an active metal, followed by molding, drying, and calcination to obtain the catalyst. A catalyst for the processing and conversion of waste plastics obtained using the above preparation method is also provided. The catalyst possesses both hydrogenation and cracking functions, and has advantages such as high activity, good selectivity, and simple preparation method. When used for waste plastic processing, the conversion of waste plastics can be completed in only one step.

This invention relates to the field of hydrogenation technology, and discloses a hydrogenation catalyst, its preparation method, and its application. The method includes: reacting an acidic solution containing aluminum and titanium with an alkaline solution containing aluminum to form a gel, obtaining a solid gel product; aging the solid gel product in the presence of a precipitant to obtain an aging product; subjecting the aging product to hydrothermal treatment, followed by a first drying, to obtain titanium-containing pseudoboehmite, wherein the hydrothermal treatment temperature is higher than the aging reaction temperature; optionally shaping the titanium-containing pseudoboehmite, followed by a second drying and a first calcination, to obtain a titanium oxide-alumina composite oxide support; introducing an active component and an additive onto the titanium oxide-alumina composite oxide support, followed by a third drying and a second calcination. This method avoids using organic titanium-containing reagents to prepare a catalyst with a low titanium oxide content and a specific crystal structure in an alumina-titanium oxide composite oxide support, thereby improving the catalyst's reactivity.

The application discloses a preparation method of high-purity alumina fiber reinforced alumina composite material, which comprises the following steps: adding short-cut alumina fibers into water, adding a small amount of acid, and using high-purity alumina balls for rolling grinding; then adding high-purity nano-alumina dispersion liquid, continuously adding aluminum sol, fully dispersing the mixture, and performing spray drying to obtain alumina fiber reinforced alumina composite powder; the composite powder is subjected to dry pressing and isostatic pressing, and then ceramic balls with a diameter of 5-30 mm are prepared; and finally, high-temperature sintering is performed. The fiber powder is a fiber under a microscope and a powder under a macroscopic view, is more easily formed into a ball, and has a greatly increased toughness after use; the nano-alumina powder has excellent sintering activity, can be sintered at a lower temperature, and has better toughness because alumina grains are not easily grown; the aluminum sol has low-temperature sintering property, can bond the powder and the fiber, and finally generates alumina after high-temperature sintering, and has no impurities and high yield.

The invention relates to the technical field of insulating materials, in particular to a direct-current 10kV-35kV chemical crosslinked polyethylene insulating material and a preparation process thereof. The direct-current 10kV-35kV chemical crosslinked polyethylene insulating material is prepared from the following raw materials in parts by weight: 55-65 parts of polyethylene resin; 1.2 parts of a charge inhibitor; 1.5 to 2.5 parts of lead zirconate titanate; and 0.8 to 1.5 parts of bismuth telluride nanosheets. The piezoelectric effect of lead zirconate titanate and the thermoelectric response of the bismuth telluride nanosheet are combined, charges are actively neutralized under an electric field and a temperature gradient, space charge accumulation is radically eliminated, barium titanate coats aluminum oxide composite powder to form a dielectric constant gradient interface, electric field distribution is smoothed, and partial discharge is inhibited; liquid crystal macromolecules are directionally arranged in cooperation with a shear-induced orientation process, a molecular-level charge barrier is constructed, the breakdown field strength is remarkably improved, trace magnesium oxide serves as a charge inhibitor, efficient utilization is achieved through nanoscale dispersion and surface modification, and the raw material cost is reduced.

A silica-alumina-based composite material for producing a hydrotreating catalyst is disclosed. The silica-alumina composite generally comprises at least two silica-aluminas, where the first silica-alumina is a modified first silica-alumina and the second silica-alumina is either unmodified or modified. The first silica-alumina is modified to contain silica domains and alumina domains, as well as an interphase between the silica and alumina. The second silica-alumina may also be simultaneously or separately modified to contain silica domains and alumina domains, as well as an interphase between the silica and alumina. The first and second silica-aluminas differ in one or more physical and / or chemical characteristics, such as the silica-to-alumina ratio, surface area, pore size, pore volume, silica domain size, or alumina domain size. The present invention can be used to make catalyst substrate materials and catalysts useful for upgrading hydrocarbon feedstocks to make fuels, lubricants, chemicals and other hydrocarbon-containing compositions.

The invention relates to the technical field of powder coatings, in particular to a high-weather-resistance fluorine-free sand streak powder coating and a preparation method thereof. The preparation method of the high-weather-resistance fluorine-free sand streak powder coating comprises the following steps: preparing the flame-retardant additive; preparing an aluminum oxide composite material; preparing modified cellulose nanocrystals; and preparing the powder coating. The preparation method comprises the following steps: firstly, carrying out quaternization reaction on alkali lignin and 3-chloro-2-hydroxypropyl trimethyl ammonium chloride to prepare quaternized alkali lignin, then carrying out surface modification on modified nano aluminum oxide by utilizing a silane coupling agent, and finally, carrying out sufficient contact and compounding on the quaternized alkali lignin and the modified nano aluminum oxide to obtain the modified nano aluminum oxide composite material. The core-shell type aluminum oxide composite material with the modified nanometer aluminum oxide as the core and the quaternized alkali lignin as the shell is formed, and after the core-shell type aluminum oxide composite material is added into the powder coating, not only can the dispersity of the nanometer aluminum oxide in the powder coating be effectively improved, but also the ultraviolet aging resistance of the powder coating can be effectively improved, and then the weather resistance of the powder coating is improved.

The application provides a simulation method for arc ablation resistance of insulating material surface with pyrolysis effect, and belongs to the field of insulating material performance detection. The method comprises the following steps: establishing a simulation model; setting a model boundary condition; introducing a pyrolysis theory on the basis of MHD control equations on the fluid side to couple and simulate actual ablation conditions; and judging the arc ablation resistance of the insulating material through comparison with a TGA curve and a DTG curve of the insulating material. The application takes a dynamic power frequency alternating current arc and a non-ideal insulating material as simulation objects, is more in line with engineering practice, can simulate the surface arc ablation resistance process of any insulating material by changing the physical property parameters of the insulating material, and can introduce the TGA curve of the material to judge the arc ablation resistance performance of the insulating material, so as to accurately determine the arc ablation resistance limit and comprehensive performance of the epoxy / alumina composite material.

The application discloses a diesel oil hydro-upgrading catalyst and a preparation method and application thereof. The catalyst takes alumina as a carrier, Y type molecular sieve as an acid component, and VIB group metal and VIII group metal as active components. The catalyst is prepared by the following steps: preparing a solution containing active component compounds, then adding alumina precursors to prepare a slurry or suspension, drying, mixing with Y molecular sieve, shaping, and drying and calcining. According to the application, the active metal-alumina composite is prepared first, and then combined with Y molecular sieve, so that the acid center is avoided from being covered by the active metal, the acid amount of the catalyst is increased, the matching of the hydrogenation capacity and the ring-opening capacity of the catalyst is effectively improved, the secondary reactions such as chain breaking of the paraffin are reduced, the paraffin can be retained in the upgraded diesel oil in the maximum degree, the BMCI of the upgraded diesel oil is greatly reduced, and the maximum production of straight-run diesel oil and high-quality ethylene cracking raw materials is realized.

The invention provides a catalyst composition comprising a) platinum; b) rhodium; and c) a ceria-alumina composite, a zirconia composite, or a mixture thereof, wherein the platinum is supported on the ceria-alumina composite, the zirconia composite, or the mixture thereof, wherein the rhodium is supported on the ceria-alumina composite, the zirconia composite, or the mixture thereof, wherein the CeO2 in the ceria-alumina composite is 1.0 to 50 wt% based on the total weight of the ceria-alumina composite, wherein the amount of ZrO2 in the zirconia composite is 50 to 99 wt% based on the total weight of the zirconia composite. The invention also provides a catalytic article comprising the catalyst composition and a preparation thereof.

This application relates to the field of oil refining technology, specifically disclosing a method for preparing high-purity pharmaceutical-grade tiger nut oil based on column separation and molecular distillation, and its applications. The method for preparing high-purity pharmaceutical-grade tiger nut oil based on column separation and molecular distillation includes the following steps: S1. Raw material pretreatment and preliminary refining to obtain preliminary refined oil; S2. Column separation purification: passing the preliminary refined oil through a chromatographic column packed with silica-alumina composite packing material, eluting with a hexane-ethanol mixed solvent, collecting the target eluent, and concentrating under reduced pressure to remove the eluent, obtaining column-separated refined oil; S3. Molecular distillation purification: distilling the column-separated refined oil, collecting the main fraction, and finely filtering to obtain the high-purity pharmaceutical-grade tiger nut oil. The method of this application can be used for tiger nut oil preparation, and the obtained tiger nut oil has the advantages of high purity and good stability.