61results about How to "Improve hydrogen permeability" patented technology

The invention discloses an electroslag remelting slag system with low hydrogen permeability, and a preparation method and a using method thereof. The slag system is prepared from the following chemical compositions in percentage by weight: 45 to 50 percent of CaF2, 10 to 15 percent of CaO, 30 to 35 percent of Al2O3, 5 to 10 percent of SiO2, and 5 to 10 percent of MgO, wherein the MgO is adopted toreplace partial CaO. The preparation method is to crush the compositions into particles after melting, and bake the particles. The using method adopts pre-melting slag and argon protection to carry out electroslag remelting. Compared with the prior art, the slag system and the methods have the advantages that: the slag system has low hydrogen permeability, can effectively reduce the hydrogen content in steel in the remelting initial stage to ensure that the hydrogen content in the steel in the normal remelting stage is maintained at a lower level, and the hydrogen content in the remelted steel is less than 1.5ppm.

The invention discloses a metal-organic framework (MOF) material for permeating and separating gases and a preparation method thereof. Specifically, an MOF film disclosed by the invention is provided with a functional group, which contributes to nucleating on a substrate, increase the nucleating density on the substrate and contributes to the growth of a dense film; and the functional group can coact with certain specific gases, so that selective permeation of gases is facilitated. Due to the adoption of a film preparation method disclosed by the invention, the growing process of the film is simplified, the structure and shape of the film are optimized simultaneously, and film permeating and separating performance is enhanced. The MOF film prepared with the method has the advantages of high permeation amount, high separating coefficient, low energy consumption and avoidance of secondary pollution, and is particularly suitable for permeating and separating gases such as H2, CO2, CH4 and the like.

Apparatus and methods of use thereof for the production of carbon-based and other nanostructures, as well as fuels and reformed products, are provided.

A separation membrane including an alloy including a Group 5 element and Ir, wherein the alloy includes a body centered cubic crystal structure.

Composite membrane (1) comprises a layer system consisting of a rigid non-self supporting non-metallic inorganic diffusion barrier layer (1b) and hydrogen-permeable non-porous metallic membrane layers (1c) arranged on a flexible metallic substrate (1a). Preferred Features: The diffusion barrier layer is arranged between the substrate and one membrane layer and is formed as a single layer. The single layer is open-pored and/or has micro-tears. The substrate has an open porosity in the region of 15-60%. At least one of the membrane layers is galvanically deposited on the surface of the diffusion barrier layer facing away from the substrate. An Independent claim is also included for a process for the production of the composite membrane.

Hydrogen selective coatings, coated articles and methods for their formation and for hydrogen separation or purification. The coatings are formed by atomic layer deposition of suitable metal oxides with desirable hydrogen activation energy or hydrogen flux, e.g., silicon dioxide, and can be borne on a nonporous, thin-film metal or cermet substrate, e.g., a palladium sheet or layer. The coated substrate may include a porous support for the sheet or layer. The coated article may be used as a purification membrane and the coating can protect the metal layer from contaminants in the gas or process stream from which hydrogen is being purified. In some embodiments, the coated article can provide such protection at elevated temperatures in excess of 300° C.; and in other embodiments, can provide protection at temperatures in excess of 600° C. and even in excess of 800° C.

A method for preparing a palladium-containing layer comprises the steps of cleaning a top surface of the porous substrate, modifying the top surface of the porous substrate to form a planar surface, performing a seeding process on the planar surface to adhere palladium nanoparticles on the planar surface and performing an electroless plating process to form the palladium-containing layer on the planar surface. The step of modifying the top surface of the porous substrate includes filling holes of the porous substrate with aluminum oxide particles, coating a sol-gel containing aluminum oxide or silicon oxide on the top surface of the porous substrate, The step of performing a seeding process on the planar surface includes exposing the planar surface of the porous substrate in a nanocolloidal solution having dispersed palladium nanoparticles derived from a palladium-containing species and a surfactant.

There is provided a hydrogen separation membrane capable of providing high hydrogen permeability and accommodating an increase in pressure difference, a hydrogen separation unit, and a manufacturing method for a hydrogen separation membrane. The hydrogen separation unit 1 has a hydrogen separation membrane 10 and a metallic porous support sheet 20 attached to the hydrogen separation membrane 10. By forming a plurality of pits in the surface of the hydrogen separation membrane 10, a thick-wall portion 15 having a large thickness and a thin-wall portion 16 having a small thickness are provided on the hydrogen separation membrane 10. Also, as a method for forming pits i.e. thin-wall portions 16, etching process is used.

The invention discloses a mixed conductor hydrogen permeation membrane containing Zr system and Tm system perovskite and a preparation method and an application thereof; the chemical formula of the hydrogen permeation membrane is SrCe0.95-xZrxTm0.05O3-delta; wherein, x is not less than 0.1 and not more than 0.40 and delta is not less than 0 and not more than 0.5. The preparation method comprises the following steps: preparing a precursor by EDTA-citric acid combination complexometry, sintering at 1000 DEG C for 7-10h to obtain powder, pressing the powder at 10-40MPa to obtain membranes by stationary method and finally roasting the membranes at 1100-1525 DEG C to obtain the mixed conductor hydrogen permeation membrane containing Zr system and Tm system perovskite. The hydrogen permeation membrane is perovskite oxide which is doped with Zr and Tm at the same time, has higher hydrogen permeability and high stability in reducing atmosphere and can be used for separating hydrogen from a mixed gas containing hydrogen.

The invention provides a preparation method of an Nb-based amorphous alloy and a stripe and a hydrogen permeating metal film of the Nb-based amorphous alloy, According to the preparation method, the Nb-based amorphous alloy has the chemical formula as Nb0.42NiaCobZrcMd, wherein M=Ta, or Ti; a, b, c and d are respectively the atomic percentage of each component, wherein a is more than or equal to 0.30 and less than or equal to 0.40, b is more than or equal to 0.05 and less than or equal to 0.15, c is more than or equal to 0.04 and less than or equal to 0.02, d is more than or equal to 0 and less than or equal to 0.08, and the sum of a, b, c and d is equal to 0.58. With the adoption of the preparation method provided by the invention, the alloy components are further improved; the hydrogen permeating performance and thermal stability of the Nb-based amorphous alloy stripe and the hydrogen permeating metal film are improved; the Nb-based amorphous alloy capable of separating hydrogen and purifying is prepared, and the Nb-based amorphous alloy stripe and the hydrogen permeating metal film which have high performance of hydrogen permeating and are capable of separating and hydrogen and purifying can be obtained.

The invention discloses a hydrogen permeating alloy material and a method for preparing the same, and the alloy comprises the following components by molar percentage: titanium of 23mol%-54mol%, cobalt of 21mol%-39mol% and tantalum, titanium, cobalt and tantalum of which the total content is of 98-100mol%.The manufacturing of the alloy material comprises steps of putting titanium, cobalt and tantalum with a purity of more than 99% into a non-consumable vacuum arc furnace, vacuumizing to a pressure below 3*10 3 Pa, filling in argon of high purity to a pressure of 4*10 Pa, and then smelting. The alloy material of the invention has the hydrogen permeability and excellent hydrogen brittleness resistance ability higher than pure palladium under 573-673K, while the cost of the alloy material is only about 1/100 of that of the pure palladium, thus, the alloy material can be used for hydrogen gas isolation and purification, and can also be used for a catalytic-reformed compact membrane reactor and the like.

The invention relates to the field of fuel cells and discloses a low temperature electrolyte membrane of an H-SOFC (high temperature solid oxide fuel cell) and a preparation method. The method comprises the following steps of: (1) mixing a raw material A and a raw material B, adding a doping oxide to prepare a doped compound in an A2B2O7 solid solution fluorite structure, (2) adding the doped compound into concentrated nitric acid, di-ethyl alcohol and citric acid to prepare doped nano gel, and (3) performing drying, pressing, sintering, annealing and cold treatment on the doped nano gel to form a doped nano ceramic membrane material. Compared with the common electrolyte, since a reaction occurs at a cathode, the electrolyte membrane of the fuel cell is good in structural stability and durability and high in mechanical strength; output power of a cell is stable for a long time; the cell is low in working temperature and high in electrical efficiency; and the fuel cell electrolyte membrane is simple in preparation process and low in production cost and has better economic advantages and application prospects.

In an AA alkaline battery according to the present invention, the opening of a battery case is sealed with a gasket. In the battery case, a positive electrode, a negative electrode, a separator, and an alkaline electrolyte are provided. The negative electrode contains 4.0 g or more of zinc. The gasket has a hydrogen gas permeability coefficient, per one gasket, in the range from 1.2×110⁻¹⁰ (cm³H₂(STP)/sec·cmHg) to 9.9×10⁻¹⁰ (cm³H₂(STP)/sec·cmHg), both inclusive.

A fuel cell according to the invention comprises a multilayer proton exchange membrane having high proton conductivity in the temperature range of 300-500° C. This is achieved by the use of very thin (<1 μm) metal oxide polymer films on a metal substrate by electrolytic anodizing of a metal alloy. An exemplary proton exchange membrane according to the invention comprises a Ta_2-xHf_xO₅ film fabricated on a niobium foil. The invention allows for a significant increase in power density and, therefore, a significant reduction in fuel cell cost per unit power.

The invention relates to a chemical plating repairing method for a palladium or palladium alloy composite film. A solution or colloid of a metallic compound is used as a repairing liquid which is dipped into a film defect through capillary force and suction force and reduced to form metal particles that are filled into the defect, then a metal eliminating film is deposited by using a chemical plating method, wherein the metal particles play a role of a catalyst to the chemical plating. The method can be used for repairing the film, and can be alternated with the preparation process of the film, thereby realizing higher film compactness under the condition of same film thickness, or enabling the film to be thinner under the condition of film compactness, greatly improving the hydrogen penetrating property of the film and realizing higher hydrogen purity.

The invention discloses a preparation and measuring method of a mixed conductor ceramic membrane used for H2S decomposition. The preparation and measuring method comprises following steps: a precursor of the mixed conductor ceramic membrane is prepared via a certain method; the precursor is subjected to calcining in a furnace for a certain period of time so as to obtain a phase-formed powder; shaping is realized via a certain method, and sintering is carried out so as to obtain the finished product material with special shapes. The finished product material is delivered into a testing device, and H2S decomposition testing is carried out at certain operation conditions. The preparation method is simple and feasible; production efficiency is high; cost is low; material operation stability is excellent; and the preparation method is convenient for industrialized large-scale production.

The invention relates to a preparation method of an unsymmetrical composite ceramic hydrogen permeation membrane, and belongs to the technical field of environment-friendly materials. According to themethod, a tungsten acid rare earth compound with good chemical stability is selected as a membrane material, electronic conductive phase metal Ni is led into the membrane, nickel in an ion form is led into the tungsten acid rare earth compound by a citric acid-nitrate combustion method, simple-substance Ni is reduced, an electron conduction channel is formed, the bulk phase diffusion rate of themembrane is increased, hydrogen permeation amount of a diaphragm is increased, two phases of the a prepared two-phase membrane are more uniformly mixed, and the membrane has higher hydrogen permeationamount and chemical stability. According to the method, rare earth nano-particles with high catalytic activity are deposited on the inner wall of a green diaphragm of the hydrogen permeation membraneand serve as supporting frameworks, the rare earth nano-particles and conductive-phase metal Ni form continuous conductive grids, electrochemical reaction active sites are increased, the hydrogen permeation membrane has good catalytic activity, and poor stability and hydrogen permeation rate of the hydrogen permeation membrane are effectively improved.

Disclosed is a hydrogen separation alloy which is adoptable to a product having a large surface area of a side where hydrogen permeates and which has such a metallographic structure as to improve hydrogen permeability and to improve hydrogen-embrittlement resistance. The hydrogen separation alloy used herein is represented by the compositional formula: Nb_{100−(α+β)}M¹_αM²_β where M¹ is at least one element selected from the group consisting of Ti, Zr and Hf; M² is at least one element selected from the group consisting of Ni, Co, Cr, Fe, Cu and Zn; 10≦α≦60, 10≦β≦50, and α+β≦80. The alloy contains inevitable impurities. And the alloy includes two phases, i.e., an Nb-M¹ phase serving as a hydrogen-permeable phase, and a M²-M¹ phase serving as a hydrogen-embrittlement-resistant phase. The hydrogen-permeable phase and the hydrogen-embrittlement-resistant phase have an elongated structure resulting from rolling. The hydrogen-permeable phase occupies 35% to 70% of an arbitrary 10 μm×10 μm region in a 50 μm×50 μm observation plane of a cross section of the alloy under an electron microscopic observation, the cross section is taken in a direction of thickness reduced by the rolling and in a direction of rolling and flattening.

The invention discloses a nickel/titanium/vanadium nanowire alloy hydrogen permeability membrane and a preparing method and application. The method comprises the following steps that nickel, titaniumand vanadium particles are taken and evenly mixed to obtain mixed metal powder; the mixed metal powder is put into a smelting device to be smelted, and a nickel/titanium/vanadium alloy ingot casting is obtained; the nickel/titanium/vanadium alloy ingot casting is subjected to heat preservation for 30 min at the temperature of 900 DEG C, furnace cooling to the room temperature is carried out, and annealing is finished; the annealed nickel/titanium/vanadium alloy ingot casting is forged, the forging temperature is 750 to 850 DEG C, forging starting temperature is 780 DEG C, and rod-like nickel/titanium/vanadium alloy is obtained; the nickel/titanium/vanadium alloy is subjected to drawing at the temperature of 450 to 550 DEG C, and the filamentous nickel/titanium/vanadium nanowire alloy hydrogen permeability membrane is obtained. The prepared nickel/titanium/vanadium nanowire alloy hydrogen permeability membrane has the higher hydrogen permeability rate, higher plasticity and toughness and lower hydrogen embrittlement susceptibility.