WO1995027556A1 - Procede de production de membranes a partir de poudres nanoparticulaires - Google Patents

Procede de production de membranes a partir de poudres nanoparticulaires Download PDF

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Publication number
WO1995027556A1
WO1995027556A1 PCT/US1995/004352 US9504352W WO9527556A1 WO 1995027556 A1 WO1995027556 A1 WO 1995027556A1 US 9504352 W US9504352 W US 9504352W WO 9527556 A1 WO9527556 A1 WO 9527556A1
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WO
WIPO (PCT)
Prior art keywords
accordance
powder
nanometer
size
size particles
Prior art date
Application number
PCT/US1995/004352
Other languages
English (en)
Inventor
Yong S. Zhen
Kenneth E. Hrdina
Original Assignee
Institute Of Gas Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Institute Of Gas Technology filed Critical Institute Of Gas Technology
Priority to AU23811/95A priority Critical patent/AU2381195A/en
Publication of WO1995027556A1 publication Critical patent/WO1995027556A1/fr

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0039—Inorganic membrane manufacture
    • B01D67/0041—Inorganic membrane manufacture by agglomeration of particles in the dry state
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0039—Inorganic membrane manufacture
    • B01D67/0041—Inorganic membrane manufacture by agglomeration of particles in the dry state
    • B01D67/00413—Inorganic membrane manufacture by agglomeration of particles in the dry state by agglomeration of nanoparticles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/14—Other self-supporting filtering material ; Other filtering material
    • B01D39/20—Other self-supporting filtering material ; Other filtering material of inorganic material, e.g. asbestos paper, metallic filtering material of non-woven wires
    • B01D39/2027—Metallic material
    • B01D39/2031—Metallic material the material being particulate
    • B01D39/2034—Metallic material the material being particulate sintered or bonded by inorganic agents
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/14—Other self-supporting filtering material ; Other filtering material
    • B01D39/20—Other self-supporting filtering material ; Other filtering material of inorganic material, e.g. asbestos paper, metallic filtering material of non-woven wires
    • B01D39/2068—Other inorganic materials, e.g. ceramics
    • B01D39/2072—Other inorganic materials, e.g. ceramics the material being particulate or granular
    • B01D39/2075—Other inorganic materials, e.g. ceramics the material being particulate or granular sintered or bonded by inorganic agents
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0039—Inorganic membrane manufacture
    • B01D67/0041—Inorganic membrane manufacture by agglomeration of particles in the dry state
    • B01D67/00411—Inorganic membrane manufacture by agglomeration of particles in the dry state by sintering
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/12—Composite membranes; Ultra-thin membranes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/02—Inorganic material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/02—Inorganic material
    • B01D71/05—Cermet materials
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/10—Sintering only
    • B22F3/11—Making porous workpieces or articles
    • B22F3/1103—Making porous workpieces or articles with particular physical characteristics
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F7/00—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
    • B22F7/002—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of porous nature
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2323/00—Details relating to membrane preparation
    • B01D2323/08—Specific temperatures applied
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2323/00—Details relating to membrane preparation
    • B01D2323/08—Specific temperatures applied
    • B01D2323/081—Heating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2323/00—Details relating to membrane preparation
    • B01D2323/10—Specific pressure applied
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
    • B22F2998/10—Processes characterised by the sequence of their steps

Definitions

  • This invention relates to a process for producing structures, in particular, membranes, having Angstrom-size pores.
  • Membranes, in particular, prepared in accordance with the process of this invention are suitable for use in applications such as high temperature gas separation and as substrate materials for the deposition of ultra-thin ceramic or metal films.
  • Membrane technology is rapidly becoming an important research area in chemical engineering, especially in the separation of gases.
  • transport of fluids, solutes or molecules through membranes can occur by one of several different mechanisms.
  • the transport of any species through membranes which is similar to any separation process in chemical engineering, is driven by the difference in free energy or chemical potential of that species across the membrane.
  • the membranes encounter various combinations of harsh chemical environments and high temperatures. Thus, it is critical to evaluate the effects of changes in the thermal chemical properties and dimension stability of membrane materials on separation performance under different operating conditions.
  • Membrane processes have attracted much attention from an energy conservation stand-point in industrial gas separation processes.
  • the separation mechanisms of gases by porous solid membranes are conventionally classified into four types: 1) Knudsen diffusion, 2) surface diffusion, 3) capillary condensation with liquid flow, and 4) molecular sieving.
  • a narrow pore size distribution in a membrane system is needed in order to obtain a high degree of separation of mixtures, the required modal size depending on the type of mixture to be separated.
  • Conventional preparation of ceramic materials starts with powders produced either from synthetic reactions without strict chemical process control or by grinding up naturally occurring minerals. To prepare the final ceramics, powders are consolidated into porous compacts, then sintered into strong, dense ceramics. During these transformations, the grain size increases, pore shapes change, and the interior pores become smaller or disappear completely.
  • Ceramic membranes having ultra-fine pores are typically formed by so-called "wet processes,” that is, processes requiring the use of a solvent. Such processes include slip casting, gel casting, extrusion, and the sol- gel process.
  • the slip casting and gel casting processes utilize large amounts of solvents as well as dispersing agents to form a slurry which is then cast in a mold to form the desired membrane.
  • Extrusion typically involves the addition of a solvent along with die lubricants and an organic polymeric binder to a ceramic powder to form a mixture which is then extruded to form, typically, tubular membranes.
  • a solution of organo- metallic material is formed and then gelled. The solvent in the gel is then removed and the remaining structure heat treated.
  • Each of the slip casting, gel casting, extrusion and sol-gel processes utilize solvents and most of these processes utilize organic additives which must later be removed. This greatly limits the minimum size of the pores, typically submicron size, which can be formed in the resulting structure due to the requirement that the removal of solvents or organics requires that the pore size in the structure be larger than the molecules being removed.
  • Zeolites are a group of minerals, both naturally occurring and synthetically prepared, whose crystal structures contain pores on the order of about 3 to 20 Angstroms in size.
  • the preparation of monolithic discs or sheets of material using zeolite with only 3 to 20 Angstrom-size connected pores is not possible because the resulting micron size powder would contain crystals of zeolite which form shapes containing micron size pores with Angstrom-size pores within the crystals.
  • a process for producing a membrane having a plurality of Angstrom-size pores comprising the steps of forming a loose powder layer of at least one of a metal powder and a ceramic powder comprising a plurality of substantially all nanometer-size particles and compacting said loose powder layer of said at least one of said metal powder and said ceramic powder to form a consolidated powder porous membrane.
  • substantially all nanometer-size particles we mean a powder having greater than about 95% nanometer-size particles.
  • a critical feature of this process is the requirement that nanometer-size ceramic powders be utilized.
  • compacting of the nanometer-size particles is carried out by cold-isostatic pressing.
  • the nanoparticulate powder be relatively uniform in size.
  • the mean pore size of the membranes produced in accordance with the process of this invention can be controlled based upon the mean particle size of the powder being pressed. That is, the smaller the mean particle size of the powder, the smaller will be the mean pore size of the resulting membrane.
  • Membranes produced in accordance with this process have a higher porosity than those produced by other known processes for producing membranes, in particular, ceramic membranes.
  • membranes having a plurality of Angstrom-size pores are produced by compacting at least one of a metal powder and a ceramic powder comprising substantially all nanometer-size particles to form a consolidated porous layer of powder, that is, a consolidated powder porous membrane, the compacting being carried out by cold-isostatic pressing.
  • compaction pressures between about 15,000 psi and about 300,000 psi are preferred.
  • nanometer size particles having a narrow particle size distribution are desirable.
  • the metal and/or ceramic powder comprise at least about 98% nanometer-size particles and that at least 95% of the nanometer-size particles be less than about 30 nanometers.
  • the particle size of the nanometer-size particles is in the range of about 2 nanometers to about 30 nanometers.
  • the consolidated powder porous membranes produced in accordance with this process are strong, the particles being bonded as a result of cold welding and electrostatic forces.
  • the strength of the membrane can be increased by fast-firing the consolidated porous layer of powder.
  • a low sintering temperature minimizes the amount of densification taking place and, thus, maintains the large porosity present in the membrane.
  • a short hold time minimizes the amount of particle growth and, thus, reduces the amount of pore growth in the resulting membrane.
  • sintering temperatures required by the process of this invention are typically a few hundred degrees lower than the temperatures required to densify the ceramic.
  • alumina can be completely densified at 1550°C, but membranes produced in accordance with this process by compacting a ceramic powder comprising nanometer-size particles of alumina may be fired at 1000"C to strengthen it.
  • the consolidated porous layer of ceramic material resulting from compaction of the ceramic powder is fired at a temperature between about 800"C and about 2000 ⁇ C.
  • the hold time for the membrane within the firing process is less than 30 minutes and, preferably less than 5 minutes.
  • a heating rate of about 0.5 ⁇ C/minute to about 2000 ⁇ C/minute is preferred.
  • YSZ Y 2 0 3 -doped Zr0 2
  • the membranes can be heat treated by fast-firing to preserve the uniformity of the pore size distribution.
  • Membranes produced in accordance with the process of this invention have a porosity of about 30% to 55%, that is, about 30% to about 55% porous.
  • the mean pore radius of the membranes produced in accordance with the process of this invention is between about 1/5 to 1/20 of the mean particle diameter of the powder used. In other words, if a powder with a mean particle diameter of 10 nanometers is used, a membrane with a mean pore radius of about 5 Angstroms will be obtained. If membrane support or multilayers of membranes are desired, powders of different particulate size can be pressed together to form membrane layers of different mean pore sizes.
  • the loose powder layer of nanometer- size particles of metal powder and/or ceramic powder is formed on a coarse particle layer of metal and/or ceramic powder particles where the coarse particle layer comprises a plurality of particles, substantially all larger than nanometer-size.
  • the loose powder layer and the coarse particle layer are simultaneously compacted together, forming a multilayer consolidated powder porous membrane.
  • the coarse particle layer is compacted and the loose powder layer is formed on the compacted coarse particle layer and subsequently compacted onto the compacted coarse particle layer to form a multilayer consolidated powder porous membrane.
  • This example demonstrates a method for making a ceramic membrane having a two-layer structure.
  • YSZ submicron size 8 mol percent Y 2 0 3 -doped Zr0 2
  • the membrane prepared in this example was found to be effective in the separation of H 2 /C0 2 mixture.
  • the membrane was found to be at least four times more permeable to H 2 than to C0 2 .
  • the gas transfusing rate across the membrane was significantly enhanced in the two-layer membrane structure compared to that of Example I.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Ceramic Engineering (AREA)
  • Composite Materials (AREA)
  • Materials Engineering (AREA)
  • Nanotechnology (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

Procédé de production de membrane dotée d'une pluralité de pores de taille de l'ordre de l'angström, selon lequel une poudre comportant des particules de taille de l'ordre du nanomètre est comprimée pour former une membrane poreuse constituée de poudre consolidée. Dans un mode préféré de réalisation de la présente invention, la poudre est comprimée par compression isostatique à froid.
PCT/US1995/004352 1994-04-07 1995-04-07 Procede de production de membranes a partir de poudres nanoparticulaires WO1995027556A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU23811/95A AU2381195A (en) 1994-04-07 1995-04-07 Process for producing membranes from nanoparticulate powders

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US22525694A 1994-04-07 1994-04-07
US08/225,256 1994-04-07

Publications (1)

Publication Number Publication Date
WO1995027556A1 true WO1995027556A1 (fr) 1995-10-19

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1995/004352 WO1995027556A1 (fr) 1994-04-07 1995-04-07 Procede de production de membranes a partir de poudres nanoparticulaires

Country Status (3)

Country Link
AU (1) AU2381195A (fr)
CA (1) CA2187330A1 (fr)
WO (1) WO1995027556A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997047419A1 (fr) * 1996-06-11 1997-12-18 British Nuclear Fuels Plc Fabrication d'articles a repartition densimetrique regulee
WO1999003559A1 (fr) * 1997-07-18 1999-01-28 N.V. Bekaert S.A. Fibre metallique frittee a utiliser dans la preparation de boissons
WO1999011362A1 (fr) * 1997-09-03 1999-03-11 Filterwerk Mann+Hummel Gmbh Element filtrant dont la structure jouant le role de filtre est recouverte d'une couche de nanoceramique
WO2000076634A1 (fr) * 1999-06-11 2000-12-21 Gas Separation Technology, Inc. Materiau poreux permeable aux gaz, pour la separation de gaz
EP1569790A2 (fr) * 2002-12-12 2005-09-07 Mykrolis Corporation Materiaux composites frittes, poreux
RU2518809C2 (ru) * 2012-03-29 2014-06-10 Государственное бюджетное образовательное учреждение высшего профессионального образования "Самарский государственный медицинский университет" Министерства здравоохранения Российской Федерации Способ получения пористых материалов

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2150390A1 (fr) * 1971-08-24 1973-04-06 Montedison Spa
US4329157A (en) * 1978-05-16 1982-05-11 Monsanto Company Inorganic anisotropic hollow fibers
WO1990000685A1 (fr) * 1988-07-06 1990-01-25 Interelectric Ag Procede pour la fabrication d'un palier radial
EP0426546A2 (fr) * 1989-10-26 1991-05-08 Toto Ltd. Filtre céramique et procédé pour le fabriquer
EP0467735A1 (fr) * 1990-07-03 1992-01-22 Alcoa Separations Technology Inc. Séparations de pyrogènes par ultrafiltration avec une céramique
EP0580134A1 (fr) * 1992-07-21 1994-01-26 Toshiba Tungaloy Co. Ltd. Procédé pour la préparation d'un alliage dur fritté à pores fins
WO1995005256A1 (fr) * 1993-08-17 1995-02-23 Ultram International, L.L.C. Procede de production de membranes poreuses

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2150390A1 (fr) * 1971-08-24 1973-04-06 Montedison Spa
US4329157A (en) * 1978-05-16 1982-05-11 Monsanto Company Inorganic anisotropic hollow fibers
WO1990000685A1 (fr) * 1988-07-06 1990-01-25 Interelectric Ag Procede pour la fabrication d'un palier radial
EP0426546A2 (fr) * 1989-10-26 1991-05-08 Toto Ltd. Filtre céramique et procédé pour le fabriquer
EP0467735A1 (fr) * 1990-07-03 1992-01-22 Alcoa Separations Technology Inc. Séparations de pyrogènes par ultrafiltration avec une céramique
EP0580134A1 (fr) * 1992-07-21 1994-01-26 Toshiba Tungaloy Co. Ltd. Procédé pour la préparation d'un alliage dur fritté à pores fins
WO1995005256A1 (fr) * 1993-08-17 1995-02-23 Ultram International, L.L.C. Procede de production de membranes poreuses

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997047419A1 (fr) * 1996-06-11 1997-12-18 British Nuclear Fuels Plc Fabrication d'articles a repartition densimetrique regulee
WO1999003559A1 (fr) * 1997-07-18 1999-01-28 N.V. Bekaert S.A. Fibre metallique frittee a utiliser dans la preparation de boissons
WO1999011362A1 (fr) * 1997-09-03 1999-03-11 Filterwerk Mann+Hummel Gmbh Element filtrant dont la structure jouant le role de filtre est recouverte d'une couche de nanoceramique
US6866697B2 (en) * 1999-06-11 2005-03-15 Gas Separation Technology, Inc. Porous gas permeable material for gas separation
US6425936B1 (en) 1999-06-11 2002-07-30 Gas Separatation Technology, Inc. Porous gas permeable material for gas separation
US6558455B2 (en) * 1999-06-11 2003-05-06 Gas Separation Technology Inc. Porous gas permeable material for gas separation
WO2000076634A1 (fr) * 1999-06-11 2000-12-21 Gas Separation Technology, Inc. Materiau poreux permeable aux gaz, pour la separation de gaz
US7314504B2 (en) 1999-06-11 2008-01-01 Gas Separation Technology, Inc. Porous gas permeable material for gas separation
EP1569790A2 (fr) * 2002-12-12 2005-09-07 Mykrolis Corporation Materiaux composites frittes, poreux
EP1569790A4 (fr) * 2002-12-12 2006-09-20 Entegris Inc Materiaux composites frittes, poreux
US7329311B2 (en) 2002-12-12 2008-02-12 Entegris, In. Porous sintered composite materials
US7534287B2 (en) 2002-12-12 2009-05-19 Entegris, Inc. Porous sintered composite materials
RU2518809C2 (ru) * 2012-03-29 2014-06-10 Государственное бюджетное образовательное учреждение высшего профессионального образования "Самарский государственный медицинский университет" Министерства здравоохранения Российской Федерации Способ получения пористых материалов

Also Published As

Publication number Publication date
CA2187330A1 (fr) 1995-10-19
AU2381195A (en) 1995-10-30

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