159 results about "Rhenium" patented technology

The invention belongs to the technical field of rhenium alloy materials, and particularly relates to a high-strength rhenium alloy material and a preparation method thereof. The rhenium alloy material is prepared from the following raw materials in percentage by mass: 12 to 24 weight percent of molybdenum, 6 to 9 weight percent of niobium, 2 to 5 weight percent of cobalt, 1 to 3 weight percent of tungsten, 0.5 to 1.2 weight percent of modified tantalum carbide, 3 to 6 weight percent of high-entropy rare earth and the balance of rhenium and other inevitable impurities. The modified tantalum carbide is prepared by the following preparation process: adding tantalum chloride, zirconium oxychloride and phenolic resin into a mixed solution of acetylacetone and n-butyl alcohol, stirring for 1-2 hours under a heating condition, dropwise adding ammonia water, continuously stirring for 0.5-1 hour, and drying to obtain a precursor; calcining the precursor, and cooling to obtain the modified tantalum carbide. The rhenium alloy prepared through the method has high hardness, good bending strength and excellent high-temperature mechanical property.

A machine tool, a machine component, a cutting blade, a drill bit, a grinding device, or a shredding / crushing device that is at least partially formed of a metal alloy that includes rhenium; said metal alloy includes a) at least 5 awt. % rhenium or b) at least 5 wt. % rhenium.

A process for producing amines by reductive amination, the process includes introducing a feed stream, the feed stream comprising an amino alcohol and a reducing agent, and hydrogen in a reaction zone of a reactor, and contacting the feed stream with a catalyst in the reaction zone. A hydrogen flow rate into the reaction zone is adjusted, and a product stream comprising ethyleneamines is extracted. The catalyst includes a carrier component selected from alumina, silica, and combinations thereof; and an active component having a first metal, a second metal, and a third metal. The first metal is selected from cobalt, nickel, and copper, the second metal is selected from rhenium, ruthenium, chromium, zinc, sodium, calcium, magnesium, strontium, lithium, potassium, barium, cesium, lanthanum, tungsten, iron, silver, titanium, manganese, aluminum, rhodium, platinum, palladium, iridium, and combinations thereof, and the third metal is niobium.

The application discloses a high specific strength high-elongation 6-series aluminum alloy anti-collision beam, which comprises a base, the upper side walls of the base are symmetrically fixedly connected with vertical plates, the opposite sides of the two vertical plates are fixedly connected with support plates, the upper side walls of the two support plates are fixedly connected with a smelting furnace, a stirring mechanism is arranged on the smelting furnace, a feeding port is formed in the upper side wall of the smelting furnace, and arc-shaped blocks are arranged on the inner bottom wall of the smelting furnace. The anti-collision beam combines the advantages of 6082 alloy and 7003 alloy, has good extrusion forming performance, the strength is greater than 340 MPa, the elongation is greater than or equal to 15%, and the elongation is improved by more than 10% compared with the 6082 alloy. The rare earth rhenium is added to refine the grains and improve the alloy strength, and the 6-series profile is subjected to double-stage aging strengthening, so that the elongation of the alloy is further improved.

The invention belongs to the technical field of powder metallurgy, and particularly relates to a preparation method of a high-density molybdenum-rhenium alloy. The compactness of the molybdenum-rhenium alloy mainly refers to the number and the size of internal pores, cracks and other defects of the molybdenum-rhenium alloy. The high compactness means that the internal structure of the molybdenum-rhenium alloy is uniform and continuous, the number of defects is extremely small, the strength, plasticity, toughness, thermal conductivity, electrical conductivity, corrosion resistance, high-temperature stability and fatigue life are improved, and premature failure, leakage, corrosion and performance degradation caused by pores are avoided. According to the preparation method of the high-density molybdenum-rhenium alloy, on one hand, in the preparation process of mixed crystals of rhenium salt and molybdenum salt, the particle size and particle size distribution of the mixed crystals are controlled through technical means, and the problem that the mixed crystals are distributed unevenly is avoided; and on the other hand, formation of internal pores and cracks is eliminated through technical means in the molybdenum-rhenium alloy powder compression molding process. And finally, the high-density molybdenum-rhenium alloy is prepared.

The application provides a catalyst, a preparation method and application thereof. The catalyst comprises a porous substrate and an auxiliary agent arranged on at least part of the surface of the porous substrate, the porous substrate comprises a Raney cobalt material, and the auxiliary agent comprises metallic rhenium, an alkali metal and an alkaline earth metal; wherein the Raney cobalt material comprises a Co-S chemical bond. The catalyst provided by the application has excellent activity, and can effectively improve the conversion rate of dinitrile compounds and the selectivity of diamines.

In a general aspect, a flexible cable communicates electromagnetic signals in a cryogenic system. In some aspects, the flexible cable includes a signal layer and a ground layer. The signal layer includes signal lines embedded in adhesive material. Each signal line includes a multilayer structure. The multilayer structure includes a layer of non-superconducting material and a layer of rhenium metal. The ground layer is laminated to the signal layer.

The invention relates to a novel functional material for X-ray protection, in particular to a liquid metal flexible shielding material and a preparation method and application thereof. The material comprises liquid metal and solid metal, the liquid metal serves as a solvent to be filled in gaps of the solid metal, the liquid metal is gallium, gallium indium, gallium indium tin, gallium indium tin zinc or mercury, and the solid metal is selected from one or more of indium, tin, gold, platinum, iridium, zirconium, niobium, molybdenum, ruthenium, osmium, rhenium, rhodium, tungsten, antimony, palladium, tantalum, hafnium, lutetium, lead, ytterbium, thulium, bismuth, silver, erbium, holmium, dysprosium, terbium, gadolinium, samarium, neodymium, lanthanum, praseodymium, cerium and europium. On the basis of compounding of the liquid metal solvent and the solid metal solute based on the liquid metal combinatology, the liquid metal and the solid metal are jointly used for protecting X-ray radiation, the comprehensive performance of X-ray protection is improved, and meanwhile the variety and number range of selectable metal elements is widened.

The invention discloses a low-density low-rhenium nickel-based single-crystal high-temperature alloy which comprises the following chemical components in percentage by weight: 2.8 to 6 percent of chromium, 5.5 to 9 percent of cobalt, 4 to 7 percent of molybdenum, 4 to 6 percent of tungsten, 4 to 7 percent of tantalum, 4 to 7 percent of aluminum, 0.07 to 0.3 percent of hafnium, 2 to 4 percent of rhenium, 1.5 to 2.5 percent of ruthenium, 0 to 0.01 percent of yttrium and the balance of nickel. Wherein in percentage by weight, the content relation of the molybdenum and the tungsten is 0.7 lt; molybdenum / tungsten lt; the content relation of molybdenum and rhenium is that molybdenum / rhenium is greater than or equal to 1.1. The strength of the alloy is improved by increasing the content of molybdenum, the contents of tungsten and rhenium are reduced, precipitation of harmful phases is reduced by comprehensively regulating and controlling the proportion of elements in rows and columns, it is ensured that the creep life of the alloy reaches the fourth-generation single crystal level, meanwhile, the alloy has the room-temperature density not higher than 8.9 g / cm < 3 >, the high-temperature low-stress durability of the alloy reaches the typical fourth-generation single crystal high-temperature alloy level, and the service life of the alloy is prolonged. The method is suitable for manufacturing advanced aero-engines.

A medical device that is partially or fully formed of a metal alloy; the metal alloy includes one of a) metal alloy that includes at least 15 awt % rhenium, b) at least 60 wt. % tungsten, at least 15 awt % rhenium, and at least 1 wt % molybdenum, c) at least 50 wt. % rhenium, at least 20 wt. % chromium, and 0.1-80 wt. % of an additive, d) greater than 50 wt. % titanium, 15-45 wt. % niobium, 1-10 wt. % zirconium, and 1-15 wt. % tantalum, e) greater than 50 wt. % titanium, 15-45 wt. % niobium, and 1-10 wt. %, f) 30-60 wt. % cobalt, 10-30 wt. % chromium, 5-20 wt. % iron, 5-22 wt. % nickel, and 2-12 wt. % molybdenum, g) 40-60 wt. % zirconium, and 40-60 wt. % molybdenum, h) 90-99.5 wt. % niobium, and 0.5-10 wt. % zirconium, or i) 55-75 wt. % niobium, 18-40 wt. % tantalum, 1-7 wt. % tungsten, and 0.5-4 wt. % zirconium.

The invention discloses a method for manufacturing a molybdenum-rhenium alloy single crystal bar through an electric arc fuse additive. The method comprises the following steps that firstly, molybdenum powder and rhenium powder are mixed; 2, cold isostatic pressing; 3, sintering; 4, rotary swaging and wiredrawing; 5, alkali washing and ethanol cleaning; 6, the clean molybdenum-rhenium alloy wire is put into an electric arc fuse wire additive manufacturing molybdenum-rhenium alloy single crystal device; 7, fixing molybdenum-rhenium alloy single crystal seed crystals; 8, introducing cooling water; and ninthly, argon is introduced for gas washing, electric arc fuse wire additive manufacturing is conducted, and the molybdenum-rhenium alloy single crystal bar is obtained. The molybdenum powder and the rhenium powder are prepared into the molybdenum-rhenium alloy wire, then the molybdenum-rhenium alloy single crystal device is matched with the molybdenum-rhenium alloy single crystal seed crystals and the electric arc fuse wire additive manufacturing, electric arc fuse wire additive manufacturing is carried out, oriented surface growth of the molybdenum-rhenium alloy single crystal rod is achieved, preparation of the molybdenum-rhenium alloy single crystal rod is achieved, and the production efficiency of the molybdenum-rhenium alloy single crystal rod is improved. The method is suitable for preparing the molybdenum-rhenium alloy single crystal bar in the technical field of directional solidification of refractory alloy, the raw material utilization rate is increased, and the cost is reduced.

The application discloses a zinc alloy and a preparation method thereof, and comprises a zinc alloy base material and a polypyrrole cerium oxide composite film; the outer surface of the zinc alloy base material has a microporous structure, and the microporous structure of the zinc alloy base material is coated with a layer of polypyrrole cerium oxide composite film; the zinc alloy base material is made of raw materials with the following mass percentages: 0.05-0.12% of aluminum, 0.1-0.3% of manganese, 0.8-1.5% of copper, 0.01-0.1% of titanium, 0.01-0.05% of rhenium, and the balance of zinc. The zinc alloy and the preparation method thereof have the advantages that the zinc alloy base material is prepared by adopting a melting casting-equiaxed angle extrusion-heat rolling-cold rolling combined process, the microporous structure is prepared on the surface of the zinc alloy base material, and the microporous structure is coated with a layer of polypyrrole cerium oxide composite film, so that the final zinc alloy has good mechanical properties and good corrosion resistance.

Manufacturing a detector device such as a microchannel plate (MCP) includes using a first atomic layer deposition (ALD) process with first precursor materials to deposit a resistive layer on a substrate and thereby form a resistive-coated substrate, the first precursor materials including a conductive rhenium material and an insulative aluminum material. The resistive layer is deposited as interspersed conductive and insulative regions of a rhenium constituent and an aluminum constituent respectively in a predetermined ratio. A second ALD process with second precursor materials is used to deposit an emissive layer on the resistive-coated substrate, the emissive layer being constituted to generate electrical carriers in use of the detector device to be sensed by external sensing circuitry as detected events. The first ALD process is performed at a deposition temperature sufficiently above 200° C. to obtain a dark-current contribution of the resistive layer of less than about 600 Hz / cm2.

This invention discloses a slow-release sulfurizing agent Fe x S y Its preparation method and application as a rhenium extraction material: Step 1: The pyrite-doped metal roasting product is subjected to an oxidation-reduction reaction, and the raw material is dried and roasted to obtain the product; Step 2: The product is ground and screened to obtain the slow-release sulfiding agent Fe. x S y The slow-release sulfurizing agent Fe x S y Its application, as a slow-release sulfide material, is used in metal corrosion protection, heavy metal-containing wastewater treatment, and soil sulfide replenishment; this invention achieves S 2 The slow release of the substance controls the local effective concentration and forms highly active iron-sulfur chemical bonds. At the same time, the crystal structure is a low-stability crystal system, thus exhibiting high chemical reactivity, which has obvious technical advantages over existing rhenium extraction materials.

The invention discloses a preparation method of high-purity ammonium rhenate, which comprises the following steps: adding rhenium-rich slag and water into a high-pressure kettle, uniformly stirring, adding hydrogen peroxide, heating, pressurizing and leaching, precisely filtering after leaching, and standing to obtain a leaching solution; the leachate is treated through a four-stage anion exchange column, the saturated ion exchange column is resolved through high-quality ammonia water, and resolved liquid is purified and enriched ammonium rhenate liquid; and performing high-temperature thermal crystallization on the purified and enriched ammonium rhenate solution under the action of micro-pressure ultrasonic waves, performing centrifugal separation to obtain high-purity ammonium rhenate crystals, and performing high-temperature drying to obtain a high-purity ammonium rhenate product. The method is simple in process, and the prepared product is high in activity, high in crystallization rate and excellent in purity and has high application value.

The invention discloses a method for recovering rhenium from nickel-based superalloy, which comprises the following steps: melting the nickel-based superalloy into alloy liquid, and atomizing the alloy liquid under inert gas to obtain alloy powder; under stirring, the alloy powder and an acid solution are mixed, oxygen is introduced, the total pressure of a reaction system is 0.5-0.8 MPa, the temperature is increased to 110-130 DEG C, ultrasonic waves are started, the ultrasonic power density is 30-50 W / L, the ultrasonic working frequency is 20-40 kHz, and oxygen bubbles with the average diameter being 10-30 micrometers are introduced for a leaching reaction; and collecting the leachate, adjusting the pH value of the leachate to 1.0-2.5 by using ammonia water, and carrying out extraction, back extraction and crystallization. According to the method, efficient and complete leaching of the nickel-based superalloy is achieved, so that the leaching rate of rhenium is increased, and the leaching time of rhenium is shortened; meanwhile, the recovery rate of rhenium and the purity of rhenium products can be improved.

The invention belongs to the technical field of catalyst metal content detection, and discloses a method for analyzing and determining cesium / rhenium content in a catalyst containing alpha-alumina. The method is simple and convenient to operate, rapid in analysis and high in accuracy. In view of no publicly reported analysis method for the content of cesium and rhenium in the alpha-alumina-containing catalyst, the method can fill the blank in the field, can dissolve a sample to a greater extent, convert cesium and rhenium into a soluble ion state and select the optimal test condition of an instrument, and can simultaneously determine cesium and rhenium, thereby saving resources, reducing the cost and improving the analysis efficiency. The relative standard deviation (RSD, n = 8) of the content determination result of cesium and rhenium is less than 2%, the adding standard recovery rate is 97.4-103.7%, the interference of matrix aluminum in the catalyst is shielded, and the accuracy of the analysis method is high.

The present invention relates to a method of producing adipic acid, including a step (hydrogenation step) of reacting 3-hydroxyadipic acid-3,6-lactone with hydrogen in an aqueous solvent in a presence of a hydrogenation catalyst. The hydrogenation catalyst preferably includes one kind or two or more kinds of transition metal elements selected from the group consisting of palladium, platinum, ruthenium, rhodium, rhenium, nickel, cobalt, iron, iridium, osmium, copper, and chromium.

The utility model provides a continuous horizontal reaction kettle for extracting rhenium metal, which comprises a reaction kettle main body, one end of the reaction kettle main body is provided with a detachable cover, one side of the detachable cover is provided with a motor, one end of an output shaft of the motor is fixedly connected with a stirring piece through a coupling, and the other end of the output shaft of the motor is provided with a stirring rod. The sealing assemblies are arranged between the reaction kettle main body and the detachable cover, each sealing assembly comprises a movable ring, a sealing ring is adhered to the inner wall of each movable ring, and the two movable assemblies are symmetrically arranged on the surface of the reaction kettle main body and located on one side of each movable ring. According to the continuous horizontal reaction kettle for extracting rhenium metal provided by the utility model, the detachable cover with the motor and the stirring piece is arranged at one end of the reaction kettle main body and is matched with the movable ring with the sealing ring for operation, so that residues on the inner wall of the reaction kettle main body can be cleaned by the stirring piece and the motor; the stirring piece can be detached from the interior of the reaction kettle main body to clean surface residues.

The invention relates to the technical field of rhenium-containing leachate suction filtration, in particular to an efficient suction filtration method for rhenium-containing leachate, which comprises the following steps: adding a filter aid into the rhenium-containing leachate, and uniformly stirring for reaction to obtain pretreated rhenium-containing leachate; the pretreated rhenium-containing leachate is injected into a temporary storage tank, and supernate and settled turbid liquid are formed after standing separation; pumping the supernate into a vacuum suction filtration machine for vacuum suction filtration treatment; and pumping the settled turbid liquid into a centrifugal machine for centrifugal separation, then pumping the formed separated liquid into a vacuum suction filter for vacuum suction filtration treatment, and combining the two suction filtrates. The activated aluminum oxide is used for pretreatment, and the supernate and the settled turbid liquid are respectively subjected to suction filtration treatment in cooperation with standing, so that the suction filtration efficiency is greatly improved, and the suction filtration time is shortened; the filter cloth and the filter paper are alternately utilized to form the filter layer, the filter cloth layer intercepts most of precipitates, and a small amount of fine particles are further intercepted by the filter paper after penetrating through the filter cloth, so that the suction filtration effect is improved.

The invention relates to the technical field of composite carbon materials, in particular to a metal carbide modified carbon material and a preparation method and application thereof. The preparation method provided by the invention comprises the following steps: mixing a carbon material with a modification element precursor to obtain mixed powder; and calcining the mixed powder in a protective atmosphere or a vacuum environment to obtain the metal carbide modified carbon material, the modification elements in the modification element precursor comprise one or more of scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, yttrium, zirconium, niobium, molybdenum, technetium, ruthenium, rhodium, palladium, hafnium, tantalum, tungsten, iridium and rhenium; the carbon material is an unmodified carbon material or a three-dimensional structure graphene modified carbon material. According to the preparation method, the coupling and adhesion capacity between the metal carbide and the carbon material can be remarkably improved, so that the carbon material has excellent structural stability, and the carbon material is applied to the fields of thermal management materials, high-strength and high-conductivity metal-based composite materials, high-conductivity and high-thermal-conductivity resin-based composite materials and polishing agent abrasives.

This invention discloses a method for adsorbing rhenium in solution using aminosilane-functionalized hydrothermal carbon, belonging to the field of strategic rare metal separation technology. The invention uses agricultural waste bamboo shoot shells as raw material, which are washed, dried, and pulverized, then mixed with N-2-aminoethyl-3-aminopropyltrimethoxysilane (KH-792) in an ethanol solution. The mixture is reacted under hydrothermal conditions to obtain aminosilane-functionalized hydrothermal carbon, which is then used to adsorb rhenium from low-concentration rhenium-containing solutions. The method described in this invention is simple, uses readily available raw materials, and the prepared aminosilane-functionalized hydrothermal carbon effectively adsorbs ReO4 from low-concentration rhenium-containing solutions. ‑ It has a high adsorption capacity, which is more than 10 times higher than that of unfunctionalized hydrothermal carbon, significantly improving the recovery efficiency of rhenium in low-concentration rhenium-containing solutions. It not only provides a new type of high-efficiency adsorbent for the recovery of rhenium resources, but also realizes the high-value utilization of agricultural waste bamboo shoot shells.

The invention discloses rhenium alloy spherical powder, a preparation method and application, and the preparation method of the rhenium alloy spherical powder comprises the following steps: reacting and drying a metal acid ammonium solution containing ammonium rhenate to obtain precursor powder; the metal acid ammonium solution also comprises at least one of ammonium molybdate and ammonium tungstate; the precursor powder is sequentially subjected to first-stage hydrogen reduction and second-stage hydrogen reduction, and rhenium alloy pre-alloyed powder is obtained; the time of the first-stage hydrogen reduction is 300-450 DEG C, the heat preservation time is 1-2 hours, the time of the second-stage hydrogen reduction is 700-1100 DEG C, and the heat preservation time is 1-3 hours; and radio frequency plasma spheroidizing is conducted on the rhenium alloy pre-alloyed powder, and the rhenium alloy spherical powder is obtained. According to the method, the technical bottlenecks of'uneven components, high oxygen content, poor sphericity and difficulty in SLM forming 'in preparation of the refractory rhenium alloy powder are broken through, and the method has repeatability, parameter controllability and industrialization potential.

The invention provides a catalyst, a preparation method and application thereof. The catalyst comprises a porous matrix and an auxiliary agent arranged on at least part of the surface of the porous matrix, the porous matrix comprises a Raney cobalt material, and the auxiliary agent comprises metal rhenium, alkali metal and alkaline earth metal; wherein the Raney cobalt material comprises a Co-S chemical bond. The catalyst provided by the invention has excellent activity, and can effectively improve the conversion rate of dinitrile compounds and the selectivity of diamine.

The invention discloses a tungsten-rhenium alloy preparation method for controlling the size of a second phase, and belongs to the technical field of medical CT machine anode target material preparation. W-10wt% Re-x Al2O3 precursor powder is synthesized by adopting a wet chemical method, wherein the content of Al2O3 is realized by regulating and controlling the addition amount of aluminum nitrate pentahydrate in the precursor. And the precursor powder is subjected to reduction treatment through a tubular furnace, and alloy powder is obtained. And then, powder densification is achieved through SPS sintering, and then the overall performance of the block is improved through rolling. According to the method, the influence of the content of the second phase (Al2O3) on the alloy performance and the influence of different processes on the size of the second phase are explored, and the purpose is to determine the optimal content interval so as to meet the strict working condition requirement of the medical CT machine target material. According to the method, an effective way for preparing the high-performance W-10wt% Re alloy by combining SPS and second phase introduction is determined through experiments, and the way has the advantages of process simplification and microscopic structure regulation and control.

The invention belongs to the technical field of hydrometallurgy, and particularly relates to a preparation method and application of a porous rhenium imprinted composite material. According to the technical scheme, the preparation method comprises the following steps: firstly, synthesizing silicon dioxide with a porous structure in an ionic liquid mixed system, dispersing the porous silicon dioxide in a rhenium-containing ionic liquid aqueous solution, then adding N-vinyl imidazole and 4-chloromethyl styrene, adding azodiisobutyronitrile, heating and stirring at 50-70 DEG C for 10-12 hours, and cooling to room temperature; after the reaction is completed, perrhenate ions used for imprinting are washed away with a diluted hydrochloric acid solution, meanwhile, other reactants which are not polymerized and are left on the surface are washed away, and the porous rhenium imprinting composite material is obtained through drying. When the material is applied to extraction and preparation of ammonium rhenate, the purity of the obtained ammonium rhenate product can reach 99.999% or above, the used reagent is environment-friendly, and obvious social benefits and economic benefits are achieved.

The invention discloses a device for improving the use efficiency of a mechanical seal of an oxygen pressure ammonia leaching molybdenum and rhenium extraction reaction kettle, which comprises a collection frame and a water tank mounted on the top surface of the collection frame and used for temporarily storing pure water, a reaction kettle assembly for oxygen pressure ammonia leaching molybdenum and rhenium extraction is mounted on the collection frame, and a stainless steel distributor is mounted on the top surface of the collection frame. A pumping assembly used for adjusting the outlet pressure along with the change of the pressure in the reaction kettle assembly is connected between the water inlet of the stainless steel distributor and the water outlet of the water tank, a balance tank is further installed on the collection frame, and the reaction kettle assembly comprises a kettle body installed with the collection frame in a combined mode. No mixed gas, no other mixture and pure water exist in the gap between the mechanical seal movable ring and the mechanical seal movable ring, crystals cannot be generated in the gap between the mechanical seal movable ring and the mechanical seal movable ring after shutdown, and the phenomenon that the mechanical seal movable ring and the mechanical seal movable ring are adhered is avoided, so that the phenomenon that the mechanical seal movable ring and the mechanical seal movable ring are damaged during secondary starting is avoided. And the mechanical seal moving and static rings are damaged due to adhesion of the mechanical seal moving and static rings.

The invention relates to the technical field of three-waste treatment, in particular to a method for extracting molybdenum and rhenium from molybdenum smelting washing flue gas wastewater step by step, which is characterized by comprising the following specific operation steps: 1) pretreatment: carrying out impurity removal and oil removal treatment on the molybdenum smelting washing flue gas wastewater to obtain a purified solution; (2) adsorption and enrichment: enabling the purified liquid to pass through selective adsorption resin, so that molybdenum and rhenium are adsorbed and enriched on the resin together; (3) molybdenum is selectively analyzed, an ammonium sulfate solution serves as a first analysis agent, and a molybdenum-rich solution is obtained; and 4) deeply desorbing rhenium, and taking ammonia water as a second desorption agent to obtain a high-purity ammonium rhenate solution. The method has the beneficial effects that the average recovery rate of molybdenum reaches 95.1%, and the average recovery rate of rhenium reaches 98.5%. More importantly, the molybdenum impurity content in the obtained ammonium rhenate product is stably lower than 10 mg / L, and it is proved that the method can still achieve efficient and high-selectivity separation of molybdenum and rhenium on the industrial scale.

By homogenizing the Re content in any cross section of the ReW wire rod body, an ReW wire rod without material fluctuations, ensuring mechanical properties, greatly contributing to the stability of the thermoelectric power, can be achieved. ReW is usually produced by powder metallurgy, mixing, molding, sintering powders. Since the sintering of ReW proceeds by solid phase diffusion, using the particle size distribution of the powder, the mixing state, the molding and sintering conditions, a phase region with locally high Re composition ratio (segregated phase of σ phase) is generated. When such a sintered body with a large variation in Re composition is processed into a rod, wire (wire rod), a non-uniformity caused by fluctuations (variations) in the amount of Re occurs in the cross section in the processing direction, the axial vertical cross section. The ReW wire rod according to the embodiments is a wire rod made of a tungsten alloy containing rhenium, in which the rhenium content in any measurement area of 1 μm in diameter per unit area in the wire rod body is less than 30 wt%.

The application discloses a shape-selective catalyst for preparing 4,4'-disubstituted diphenylmethane by alkylation and a preparation method and application thereof. The catalyst is composed of a molecular sieve and an oxide for modifying the molecular sieve. The oxide is an oxide corresponding to the highest valence of a modified element. The modified element includes phosphorus, titanium, zirconium, gallium, indium, germanium, molybdenum, tungsten, rhenium or copper. The mass content of the oxide in the catalyst is 0.01-20% in the catalyst with a mass of 100%. The catalyst has good thermal stability and chemical stability, can be repeatedly used, has a simple regeneration method and a high activity recovery rate.