147results about How to "Improves hydration resistance" patented technology

The invention relates to a thermal-state mending material taking forsterite as a raw material for converters and a preparation method thereof. The technical scheme is as follows: adopting 45-70wt% of sintered magnesia particles, 5-15wt% of graphite and 15-40wt% of forsterite fine powder as raw materials; adding simple substance silicon powder accounting for 1-10wt% of the weight of the raw materials and liquid pitch modified phenolic resin accounting for 15-25wt% of the weight of the raw materials; and stirring for 5 to 30 minutes to obtain the slurry thermal-state mending material taking forsterite as the raw material for converters. While being used, the thermal-state mending material is poured into the converter, the converter is rotated to enable the mending material to flow to the charging position, the tapping position, the bedding face and the furnace bottom of the steelmaking converter which are in need of thermal-state mending and the mending material is sintered by the heat in the converter. The material has the characteristics of abundant raw materials, low production cost, excellent hydration-proof performance, easiness in sintering at a high temperature and convenience in combination with the converter lining and is beneficial for prolonging the service life of materials of the converter lining.

The invention discloses a hydration-resistant MgO-CaO series fireproofing material and a preparation method thereof. The surface of the prepared MgO-CaO series fireproofing material is covered with a compact MgO hydration-resistant film layer. The preparation method of the invention is as follows: magnesium sand and carbon serve as reaction raw materials; MgO-CaO series material is arranged above the mixture of the magnesium sand and the carbon, and a reaction vessel is arranged in a controlled atmosphere furnace; the controlled atmosphere furnace is vacuumized, and Ar is led in the furnace for protection; the furnace body is heated, O2 is led in, and the magnesium sand and the carbon have carbothermal reduction reaction to generate Mg steam; the Mg steam diffuses to the vicinity of MgO-CaO series material so as to react with the lead-in O2; an MgO compact film is generated on the surface of the MgO-CaO series material; after the MgO compact film generated by vapor phase deposition totally covers the CaO on the surface of the MgO-CaO series material, the hydration-resistant MgO-CaO series fireproofing material can be obtained. Because the MgO compact film prevents CaO from contacting with water, the hydration-resistant performance of the MgO-CaO series fireproofing material is obviously improved. The preparation method is simple and convenient to operate, the raw materials fully react, and the production cost is low.

The invention relates to a formation method for an anode foil of an extra-high voltage aluminum electrolytic capacitor. The formation method for the anode foil of the extra-high voltage aluminum electrolytic capacitor comprises the following steps: (1) pre-treatment; (2) first level formation; (3) second level formation; (4) third level formation; (5) four level formation; (6) five level primary formation; (7) primary high temperature treatment; (8) phosphoric acid treatment; (9) fifth level secondary formation; (10) secondary high temperature treatment; (11) fifth level third formation; and (12) post-treatment. According to the formation method, the voltage in each level formation is greater than that applied in the previous level formation. The formation method also comprises a liquid feeding treatment which is carried out after second level formation or third level treatment. The formation method for the anode foil of the extra-high voltage aluminum electrolytic capacitor is simpleto control, and the bath solution components are relatively simple and better to control, so that the formation method is suitable for industrial batch production.

The invention relates to a method for producing a hydration-resistant high-purity calcium oxide crucible, which is designed for solving the technical problems that low purity of calcium oxide generally existing in the existing calcium oxide crucible easily results in the introduction of impurities into melting metal and alloy; high purity of calcium oxide results in the easy hydration of the crucible and easy cracking of the crucible during use, the service life of the crucible is short and so on. According to the method, high-purity calcium carbonate is electrically molten to obtain calcium oxide clinker which is then crushed to appropriate sizes and subsequently subject to combined gradation; the graded calcium oxide clinker is mixed with zirconia powder, then an anhydrous binder is added in the mixed powders; and a calcium oxide crucible blank is obtained by cold isostatic pressing, and then is sintered to obtain the hydration-resistant high-purity calcium oxide crucible. The method has the advantages that the performanceof metal or alloy smelted in a vacuum induction furnace with the hydration-resistant high-purity calcium oxide crucible as the liner surpasses that of the graphite crucible, the hydration resistance and the thermal shock resistance are improved, and the sintering temperature of calcium oxide is lowered; cold isostatic pressing forming is adopted so that the crucible forming is more convenient and simpler; the crucible is widely applied to the vacuum smelting industry due to the characteristics of high purity and good mechanical performance.

The invention discloses a release agent for battery grid casting and a preparation method thereof. The release agent comprises the following raw materials in parts by weight: 0.2-0.6 parts of polytetrafluoroethylene, 0.1-0.3 parts of aluminum dihydrogen phosphate, cork 1-5 parts of powder, 0.2-0.6 parts of sodium silicate, 0.6-1.5 parts of glass fiber powder, 0.1-0.6 parts of attapulgite, 0.6-2.5 parts of nano-silicon dioxide, 3-8 parts of modified aluminum tripolyphosphate, Adhesive 0.1-0.5 parts, stabilizer 0.2-0.8 parts, deionized water 90-120 parts. The preparation method adopts conventional mixing, heating and stirring. The mold release agent of the present invention has good sprayability, adhesion, temperature resistance, small surface tension, high compressive strength, smooth exhaust, can significantly reduce the phenomenon of air holes and cracks in the grid, and can also reduce the number of spray molds , improve production efficiency and save costs.

The invention provides a preparation method of moisture-proof modified electrical-grade magnesium oxide. The preparation method comprises the steps that electrical-grade magnesium oxide powder and a silicon oxide assistant are mixed to prepare an electrical-grade magnesium oxide base material; an organic silicon moisture-proof agent and a diluent are mixed to prepare an organic silicon moisture-proof agent alkyl mixture; the organic silicon moisture-proof agent alkyl mixture is electrostatically sprayed to the electrical-grade magnesium oxide base material, mixing and stirring are performed toobtain modified electrical-grade magnesium oxide powder, and the moisture-proof modified electrical-grade magnesium oxide is prepared after drying. The invention also provides the moisture-proof modified electrical-grade magnesium oxide obtained through the above steps and application thereof. The moisture-proof modified electrical-grade magnesium oxide adopts the electrostatically sprayed organic silicon moisture-proof agent alkyl mixture, the organic silicon moisture-proof agent is uniformly sprayed to the surface of the electrical-grade magnesium oxide powder to form a hydrophobic dampproof coating, the moisture resistance, water resistance and insulation properties can be remarkably improved, the use amount of the organic silicon moisture-proof agent is saved, and the moisture-proof modified electrical-grade magnesium oxide is economic and friendly to the environment.

The three-step preparation method for CaO sand comprises: first, calcining the limestone for CaO and then the light CaCO3; adding 0.1-5% micro-powder of MgO or ZrO2 with size <=3 mu m into the light CaCO3 to mix evenly and briquette; then, re-calcining for 2-5h at 1200-1600 DEG C, natural cooling to normal temperature, and obtaining the sand. This invention decreases fire temperature obviously, and improves the product property without low-melting point phase.

The invention relates to a preparation method of a formed foil used for low-voltage aluminum electrolytic capacitors. The aluminum foil is respectively added with two new treating agents during formation, i.e. phosphite and amino trimethylene phosphonic acid ( ATMP); the aluminum foil which generates a filam is put in a phosphate dilute solution to be chemically treated, and a layer of aluminum phosphide film is generated on the surface of the aluminum foil to improve the hydration resistance of the foil; the aluminum foil is formed in an ATMP solution, which ensures that not only a hydration resistant phosphating film can be generated, but also the formed aluminum foil has high efficiency and more complete covering; the solubility of oxide film is much lower, thereby a very good water resistant film is obtained and the aluminum foil obtains higher electrostatic capacity simultaneously.

The invention discloses a protection material for a plasma spray header and relates to a plasma equipment anticorrosion technology used in a semiconductor etching technique. The protection material for the plasma spray header mainly comprises magnesium oxide taken as a main material, calcium oxide with the doping content of 0.5-3wt% in the main material and yttrium oxide with the doping content of 0.5-5wt% in the main material. The invention also provides a preparation method and an application method of the protection material. By adopting the protection material, anticorrosion property of the plasma spray header in a high plasma environment for a long time can be obviously improved, and service life of the plasma spray header can be prolonged, so that production cost of a semiconductor material is reduced.

The invention provides a carbon monoxide transformation catalyst carrier for a high pressure technology. The carbon monoxide transformation catalyst carrier is prepared from 5 to 30 parts by weight of kaolin powder, 30 to 60 parts by weight of alumina powder and 10 to 40 parts by weight of magnesium oxide or magnesium hydroxide. Through utilization of kaolin powder, alumina powder and magnesium oxide or magnesium hydroxide having a certain ratio as raw materials, magnesium aluminate spinel structure compactness is effectively improved without increasing of a calcination temperature so that catalyst hydration resistance is improved; hydration under working conditions is avoided; high catalyst strength is kept in use; and crushing and wearing phenomenon is avoided.

The invention relates to a high-calcium-oxide-content calcium oxide material and a preparation method thereof. The technical scheme of the preparation method is that 30wt% to 70wt% of calcium oxide particle and 30wt% to 70wt% of calcium oxide fine powder are used as raw materials, anhydrous phenolic resin which is 2wt% to 6wt% of the raw materials is additionally added, and an obtained mixture is agitated for 2 to 20 minutes, is subjected to compression molding, then is subjected to heat treatment for 8 to 24 hours in a condition of 180 to 300 DEG C, and is naturally cooled, so that the high-calcium-oxide-content calcium oxide material is obtained. The preparation method is simple in process; the prepared high-calcium-oxide-content calcium oxide material is high in usage temperature, stable in high-temperature performance and good in anti-hydration performance, can be used for purifying a high-temperature fused mass, and is suitably used as a high-temperature material for smelting a high-purity fused mass.

The invention relates to a method for producing a magnesium calcium ramming material for an AOD furnace from waste magnesia-calcium bricks. The magnesium calcium ramming material comprises 10-30 parts by weight of waste magnesia-calcium bricks having particle sizes of 5 to 3 mm, 10-25 parts by weight of waste magnesia-calcium bricks having particle sizes of 3 to 1 mm, 15-25 parts by weight of waste magnesia-calcium bricks having particle sizes of 1 to 0 mm and 10-25 parts by weight of fused magnesite of 150-200 meshes. The magnesium calcium ramming material also comprises 1.5-12% of a binder on the basis of the above raw material total weight. The waste magnesia-calcium bricks are subjected to water repellent treatment. The method realizes recycling of the waste magnesia-calcium bricks and observably improves water repellent performances of the magnesium calcium ramming material. The magnesium calcium ramming material satisfies refractory material use requirements on an AOD refining furnace, has a long storage life and effectively reduces an enterprise production cost.

The invention relates to the field of waterproofing of magnesium refractory bricks and in particular relates to a waterproof treatment method for magnesium refractory bricks. The waterproof treatment method is characterized in that as magnesium sulphate has the characteristics of crystal water, postproduction impregnation is carried out on the magnesium refractory bricks under vacuum condition to achieve the waterproof aim; and the waterproof treatment method comprises the following concrete operational steps of: 1) preparing a magnesium sulphate solution; 2) piling up the magnesium refractory bricks and vacuumizing; 3) injecting the magnesium sulphate solution to submerge and soak the magnesium refractory bricks; and 4) taking out the magnesium refractory bricks and carrying out heat treatment. Compared with the prior art, the waterproof treatment method for the magnesium refractory bricks has the beneficial effects that the treated magnesium refractory bricks are low in gas hole ratio, the compression strength is improved, and the treated magnesium refractory bricks have high anti-hydration capability, the problem that magnesia-alumina spinel bricks in a maerz active lime shaft kiln, magnesite-chrome bricks in a working layer of an RH (relative humidity) refining furnace and fired magnesite bricks in a permanent layer of a metallurgy electric furnace and a converter are hydrated can be effectively solved, and the reduction of influence of poor conditions such as humid climate and rainy days in the south of China to properties of the magnesium refractory bricks can be facilitated, so that the service life of the magnesium refractory bricks is prolonged.

The invention discloses a preparation method for preparing an anti-hydration magnesia-calcia refractory through phosphate tailing. The anti-hydration magnesia-calcia refractory is prepared according to the following steps that A, the phosphate tailing is dried, smashed, ground, sieved, precalcined, naturally cooled to the room temperature to be taken out, ground and sieved, and thus precalcined phosphate tailing is obtained; and B, the precalcined phosphate tailing, nano-titania, nano zirconium dioxide and a binding agent are mixed evenly, and through forming, drying and calcining, a finishedproduct is obtained. The anti-hydration magnesia-calcia refractory with the high volume density and good normal-temperature compressive strength is obtained, the preparation process is simple and easyto operate, the phosphate tailing is mainly taken as a main raw material, and the problems that the phosphate tailing is low in utilization rate, and the magnesia-calcia refractory is prone to beinghydrated are solved.

The invention discloses an anti-hydration magnesia castable, which includes following components: 25-35 parts of magnesite, 15-25 parts of spinel, 15-25 parts of corundum, 5-10 parts of calcium aluminate cement, 2-8 parts of silicon dioxide micro-powder, 1-5 parts of graphite, 3-10 parts of sodium hexametaphosphate, 4-9 parts of boric acid, 2-6 parts of oxalic acid, 3-9 parts of calcium oxide, 5-10 parts of boron oxide, 2-8 parts of nickel oxide, 15-25 parts of organic fibers and 0.1-3 parts of metallic aluminum powder. The magnesia castable has an excellent anti-hydration property.

The invention discloses a method for preparing a high-purity hydration-resisting calcium oxide crucible, wherein the method includes the steps: (1) adding yttrium oxide in a high-purity calcium hydroxide powder, carrying out ball milling, and then drying; (2) pressing the dried material into blocks, and then calcining to obtain a sintered material; (3) crushing and screening the sintered material; (4) mixing the screened material, then adding an anhydrous binder, mixing evenly, and then placing the mixture into a crucible mold; (5) vibrating to compact the material in the crucible mold, then carrying out cold isostatic pressing, and carrying out compression molding of the material, to obtain a calcium oxide crucible blank; and (6) sintering the calcium oxide crucible blank, to obtain the calcium oxide crucible. The prepared calcium oxide crucible has good thermal shock resistance and relatively high service life, better solves the problems that a conventional calcium oxide crucible is easy to hydrate when the purity is high and has impurities easily introduced to pollute melted metals and alloys when the purity is low, and is widely applied in pure steel and ultra-pure metal smelting.

The invention relates to the field of polyether amine preparation, in particular to a preparation method and an application method of a catalyst for synthesizing polyether amine. The preparation method of the polyether amine catalyst comprises the following steps: (1) potassium-based montmorillonite is prepared; (2) primary impregnation is carried out, namely, a supported catalyst comprises an active component and an auxiliary agent, a gamma-Al2O3 carrier is loaded with a metal salt solution containing an active component and an auxiliary agent by adopting an isopyknic impregnation method, anddrying and roasting are carried out to obtain a carrier loaded with the metal oxide; (3) secondary impregnation is carried out, namely, an equal amount of an organic amine solution of the potassium-based montmorillonite obtained in the step (1) is added into a metal salt solution for impregnation which is half of the metal salt solution in the step (2), the carrier loaded with the metal oxide obtained in the step (2) is impregnated, and drying and roasting are carried out to obtain a catalyst; and (4) reduction is carried out, namely, the modified carrier loaded with the metal oxide obtainedin the step (3) is put into a rotary furnace, and H2 is introduced for reduction to obtain the polyether amine catalyst.

The invention relates to a preparation method of MgO-CaO-ZrO2 sand. The preparation method comprises the following steps: carrying out heat treatment on dolomite ore and magnesite ore, hydrating, sieving with a 0.2 mm sieve, drying a filter body obtained by sieving, and grinding to 200 meshes or below to obtain MgO-CaO2 powder; placing MgO-CaO powder and Zr(OH)4 sol in a mixer to be evenly mixed,conducting ball pressing after mixing, and drying till the moisture is smaller than 1%; and finally, placing the mixture in a kiln to be calcined, and obtaining the MgO-CaO-ZrO2 sand. The MgO-CaO-ZrO2sand prepared by the preparation method disclosed by the invention is good in hydration resistance, high in refractoriness, high in thermal stability and strong in alkaline slag corrosion resistance,has a purification effect on molten steel, and is an ideal raw material for preparing high-grade materials such as magnesium-calcium refractory materials and ceramics.

The invention relates to a high-quality dolomite-periclase-calcium zirconate composite fireproof material suitable for smelting stainless steel, special steel AOD furnace and refining ladles. The adopted raw materials mainly comprise, by weight, 8-10% of magnesium calcium sand with a particle size of 5-8 mm, 9-18% of magnesium calcium sand with a particle size of 3-5 mm, 10-22% of magnesium calcium sand with a particle size of 1-3 mm, 5-10% of calcium zirconate with a particle size of 0.5-1 mm, 5-10% of magnesia with a particle size of 0.5-1 mm, 3-10% of 600 mesh electric melting calcium zirconate, 15-24% of magnesia with a particle size of less than or equal to 0.5 mm, 3-10% of 400 mesh 98 large crystal magnesia, 1-3% of a binding agent, and 1-2% of a sintering agent, wherein the raw materials are subjected to mixing, molding, sintering, finished product inspection, package and other steps to prepare the material.

The invention relates to the field of catalyst preparation, and discloses a catalyst carrier, a supported catalyst, preparation methods and applications of the catalyst carrier and the supported catalyst, and a method for preparing hydrogen by methane steam reforming. The carrier comprises La modified aluminum oxide, CaO and MgO, the carrier has pores with pore sizes of larger than 100 nm, and a volume of pores with pore sizes of larger than 100 nm is 75-95% of a total pore volume of the carrier. The carrier provided by the invention has high strength and high hydrothermal stability, and whenthe carrier provided by the invention is adopted to prepare a methane steam reforming catalyst, a dispersion degree of active metals, activity of the catalyst, carbon deposition resistance and structural stability can be significantly improved.

The invention relates to a pit patching material for a converter, wherein the pit patching material comprises the following raw materials by weight: 60-85 parts of the mixed powder of dolomite and sintered magnesia, 10-20 parts of modified asphalt, 2-5 parts of an additive, and 6-10 parts of a wetting agent, and a ratio of the dolomite to the sintered magnesia in the mixed powder is 1:(1-2). According to the present invention, the pit patching material has advantages of good self-flowing property, hot strength, corrosion resistance, thermal shock resistance and short hardening time so as to reduce the blowing-out maintenance time of the converter and improve the working efficiency; and the pit patching material and the converter working line are well adhered so as to prevent the pit patching material from peeling off during the use.