EP0040282A1
Expired / Lapsed
EP
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Process for the production of a dry inorganic ultrafiltration membrane and membrane produced by such a method
Assignee: Societe de Fabrication dElements Catalytiques
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Filing: 1980-05-21
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Granted: —
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Expires: 2000-05-21
Abstract
Abstract A coating is applied to a microporous support in the presence of a volatile liquid capable of drawing the coating into the support and of desolvating the coating. The liquid is thereafter volatilized with the resulting dry ultrafiltration membrane being essentially crack-free and having desirable mechanical and chemical stability. The support may be pretreated with a volatile liquid, such as acetone, prior to the applying of the coating to the support. Alternately,the coating material can be dispersed in a volatile liquid, such as methanol, to form a coating suspension that is applied to the support. The coating material, prefetably zirconia, will have a particle size within the range of from about 5 mµ to about 10µ. with the coating having a thickness of up to about 20µ. The support, such as a porous carbon tube, will have a pore volume of about 5-60% and a pore size of about 5 mµ-40µ. Stability is enhanced by firing the membrane at 25°C-1500°C, preferably at about 400°C-600°C.
Inventors
- 👤 Anthony Cacciola
- 👤 Pak Sand Leung
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 01:02
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/80; C04B41/81; C04B41/85; C04B41/87; B; B01; B01D; B01D61/00; B01D61/14; B01D61/145; B01D63/00; B01D63/02; B01D63/06; B01D63/08; B01D63/087; B01D67/00; B01D67/0039; B01D67/0046; B01D71/00; B01D71/02; B01D71/024; C04B41/009; C04B41/45; C04B41/50; C04B41/5025; B01D2323/00; B01D2323/08; B01D2323/081
Claims Analysis
Total Claims: 63
Claim 1
Independent Claim
154 words
A process for the production of a dry, inorganic ultrafiltration membrane comprising : (a) coating the surface of a microporous membrane support with a membrane coating material in the presence of a volatile liquid medium non-solvating to said coating material and capable of drawing said coating material into said support and of desolvating said coating material; i and (b) exposing the thus-treated membrane to a temperature capable of volatilizing said liquid medium to remove said liquid medium from the microporous membrane support and said membrane coating material, whereby the desolvation of said coating material prior to completion of removal of said liquid medium results in a shrinking of said coating material and the consequent filling, by said coating material, of voids produced as a result of said shrinking, thus avoiding the development of microscopic cracks that otherwise occur upon desolvation of the coated membrane, thereby forming an essentially crack-free, mechanically and chemically stable membrane.
Claim 2
Dependent Claim
154 words
A process for the production of a dry, inorganic ultrafiltration membrane comprising : (a) coating the surface of a microporous membrane support with a membrane coating material in the presence of a volatile liquid medium non-solvating to said coating material and capable of drawing said coating material into said support and of desolvating said coating material; i and (b) exposing the thus-treated membrane to a temperature capable of volatilizing said liquid medium to remove said liquid medium from the microporous membrane support and said membrane coating material, whereby the desolvation of said coating material prior to completion of removal of said liquid medium results in a shrinking of said coating material and the consequent filling, by said coating material, of voids produced as a result of said shrinking, thus avoiding the development of microscopic cracks that otherwise occur upon desolvation of the coated membrane, thereby forming an essentially crack-free, mechanically and chemically stable membrane.
Claim 3
Dependent Claim
17 words
The process of Claim 1 in which said support is essentially saturated with said volatile liquid medium.
Claim 4
Dependent Claim
19 words
The process of Claim 2 in which said coating material is applied to one side of said membrane support.
Claim 5
Dependent Claim
22 words
The process of Claim 3 in which said coating material is applied as a coating of from submicron to about 20-micron thickness.
Claim 6
Dependent Claim
30 words
The process of Claim 1 and including firing the treated membrane at a temperature of from about 25°C to about 1 500°C, said firing enhancing the stability of said membrane.
Claim 7
Dependent Claim
18 words
The process of Claim 5 in which said firing temperature is from about 60°C to about 1 200°C.
Claim 8
Dependent Claim
17 words
The process of Claim 6 in which said firing temperature is from about 400°C to about 600°C.
Claim 9
Dependent Claim
37 words
The process of Claim 1 in which said membrane coating material is taken from the group consisting of the oxides of the metals of Groups III-A, IV-A, IV-B, V-A, V-B, VI-B, VII-B and VIII, lanthanides and actinides.
Claim 10
Dependent Claim
12 words
The process of Claim 8 in which said coating material comprises zirconia.
Claim 11
Dependent Claim
32 words
The process of Claim 1 in which said membrane support has a pore size of from about 50 mµ to about 4Dv and a pore volume of from about 5% to about'60%.
Claim 12
Dependent Claim
34 words
The process of Claim 10 in which said membrane support has a pore size of from about 100 mµ to about 2 µ and a pore volume of from about 20% to about 40%.
Claim 13
Dependent Claim
15 words
The process of Claim 10 in which said membrane support comprises a porous carbon tubing.
Claim 14
Dependent Claim
60 words
The process of Claim 4 in which said coating material comprises zirconia, said membrane support comprises a porous carbon tube having a pore size of from about 50 mµ to about 40µ and a pore volume of from about 5% to about 60%, said treated membrane having been fired to a temperature of from about 25°C to about 1 500°C.
Claim 15
Dependent Claim
46 words
The process of Claim 13 in which said firing temperature is from about 60°C to about 1 200°C, and said porous carbon tube has a pore size of from about 100 mµ to about 2µ and a pore volume of from about 20% to about 40%.
Claim 16
Dependent Claim
13 words
The process of Claim 13 in which said volatile liquid medium comprises acetone.
Claim 17
Dependent Claim
13 words
The process of Claim 13 in which said volatile liquid medium comprises methanol.
Claim 18
Dependent Claim
25 words
The process of Claim 1 and including pretreating said membrane support with said volatile liquid medium prior to coating said support with membrane coating material.
Claim 19
Dependent Claim
31 words
The process of Claim 17 in which said pretreated membrane support is contacted with a suspension of said membrane coating material, said volatile liquid medium being miscible with said coating suspension.
Claim 20
Dependent Claim
14 words
The process of Claim 18 in which said coating suspension comprises an aqueous suspension.
Claim 21
Dependent Claim
47 words
The process of Claim 18 and including draining excess suspension from the surface of said membrane support, said exposing of the treated membrane to a temperature capable of volatilizing said liquid medium comprising air drying said membrane at a temperature of from about 15°C to about 100°C.
Claim 22
Dependent Claim
30 words
The process of Claim 20 and including firing the thus-treated membrane at a temperature of from about 25°C to about 1 500°C, said firing enhancing the stability of said membrane.
Claim 23
Dependent Claim
18 words
The process of Claim 21 in which said firing temperature is from about 60°C to about 1 200°C.
Claim 24
Dependent Claim
17 words
The process of Claim 22 in which said firing temperature is from about 400°C to about 600°C.
Claim 25
Dependent Claim
37 words
The process of Claim 22 in which said membrane coating material is taken from the group consisting of the oxides of the metals of Groups III-A, IV-A, IV-B, V-A, V-B, VI-B, VII-B and VIII, lanthanides and actinides.
Claim 26
Dependent Claim
12 words
The process of Claim 24 in which said coating material comprises zirconia.
Claim 27
Dependent Claim
21 words
The process of Claim 25 in which said zirconia has a particle size of from about 5 mµ to about 10'ft.
Claim 28
Dependent Claim
18 words
The process of Claim 26 in which said particle size is from about 10 mµ to about 1f.
Claim 29
Dependent Claim
26 words
The process of Claim 18 in which said liquid medium comprises an alcohol or ketone volatile at a temperature of from about 15°C to about 100°C.
Claim 30
Dependent Claim
12 words
The process of Claim 28 in which said liquid medium comprises acetone.
Claim 31
Dependent Claim
20 words
The process of Claim 25 in which said coating suspension comprises an aqueous suspension and said liquid medium comprises acetone.
Claim 32
Dependent Claim
33 words
The process of Claim 30 in which said membrane support has a pore size of from about 5m µ to about 40µ and a pore volume of from about 5% to about 60%.
Claim 33
Dependent Claim
37 words
The process of Claim 31 in which said support comprises a porous carbon tube having a pore size of from about 100 mµ to about 2µ and a pore volume of from about 20% to about 40%.
Claim 34
Dependent Claim
26 words
The process of Claim 30 in which said support comprises a porous carbon tubing and said coating material is coated on the inner surface'of said tube.
Claim 35
Dependent Claim
27 words
The process of Claim 19 in which said support comprises a porous carbon tube and said coating material is coated on the inner surface of said tubing.
Claim 36
Dependent Claim
46 words
The method of Claim 1 and including dispersing said membrane coating material in said volatile liquid medium capable of forming a suspension therewith and coating the surface of said support by contacting the support with the resulting suspension of membrane coating material in said liquid medium.
Claim 37
Dependent Claim
11 words
The process of Claim 35.in which said liquid medium comprises methanol.
Claim 38
Dependent Claim
47 words
The process of Claim 35 and including draining excess suspension from the surface of said membrane support, said exposing of the treated membrane to a temperature capable of volatilizing said liquid medium comprising air drying said membrane at a temperature of from about 15°C to about 100°C.
Claim 39
Dependent Claim
30 words
The process of Claim 37 and including firing the thus-treated membrane at a temperature of from about 25°C to about 1 500°C, said firing enhancing the stability of said membrane.
Claim 40
Dependent Claim
18 words
The process of Claim 38 in which said firing temperature is from about 60°C to about 1 200°C..
Claim 41
Dependent Claim
17 words
The process of Claim 39 in which said firing temperature is from about 400°C to about 600°C.
Claim 42
Dependent Claim
37 words
The process of Claim 39 in which said membrane coating material is taken from the group consisting of the oxides of the metals of Groups III-A, IV-A, IV-B, V-A, V-B, VI-B, VII-B and VIII, lanthanides and actinides.
Claim 43
Dependent Claim
12 words
The process of Claim 41 in which said coating material comprises zirconia.
Claim 44
Dependent Claim
21 words
The process of Claim 42 in which said zirconia has a particle size of from about 5 mµ to about 10µ.
Claim 45
Dependent Claim
18 words
The process of Claim 43 in which said particle size is from about 10 mµ to about 1µ.
Claim 46
Dependent Claim
26 words
The process of Claim 35 in which said liquid medium comprises an alcohol or ketone volatile at a temperature of from about 15°C to about 100°C.
Claim 47
Dependent Claim
12 words
The process of Claim 45 in which said liquid medium comprises methanol.
Claim 48
Dependent Claim
33 words
The process of Claim 42 in which said membrane support has a pore size of from about 50 mµ to about 40µ and a pore volume of from about 5% to about 60%.
Claim 49
Dependent Claim
37 words
The process of Claim 47 in which said support comprises a porous carbon tube having a pore size of from about 100 m to about 2t and a pore volume of from about 20% to about 40%.
Claim 50
Dependent Claim
19 words
The process of Claim 48 in which said coating material is coated on the inner surface of said tube.
Claim 51
Dependent Claim
19 words
The process of Claim 38 in which said coating material is coated on the inner surface of said tube.
Claim 52
Dependent Claim
100 words
A dry, inorganic ultrafiltration membrane comprising : a) a microporous membrane support ; and b) a microporous, dehydrated incrganic coating essentially free of cracks, said coating comprising a dry, water insoluble oxide selected from the group consisting of the metals of Groups III-A, IV-A, IV-B, V-A, VI-B, VII-B and VIII and lanthanides and actanides, the particules of said coating having a particule size within the range of from about 5 mµ to about 10 µ, said coating having a thickness of up to about 20µ, whereby said membrane has a dehydrated, essentially crack-free coating of enhanced mechanical and chemical stability.
Claim 53
Dependent Claim
100 words
A dry, inorganic ultrafiltration membrane comprising : a) a microporous membrane support ; and b) a microporous, dehydrated incrganic coating essentially free of cracks, said coating comprising a dry, water insoluble oxide selected from the group consisting of the metals of Groups III-A, IV-A, IV-B, V-A, VI-B, VII-B and VIII and lanthanides and actanides, the particules of said coating having a particule size within the range of from about 5 mµ to about 10 µ, said coating having a thickness of up to about 20µ, whereby said membrane has a dehydrated, essentially crack-free coating of enhanced mechanical and chemical stability.
Claim 54
Dependent Claim
11 words
The membrane of Claim 51 in which said coating comprises zirconia.
Claim 55
Dependent Claim
22 words
The membrane of Claim 51 in which said coating has a particule size of from about 10 m f to about 1µ.
Claim 56
Dependent Claim
32 words
The membrane of Claim 51 in which said support has a pore volume of from about 5% to about 60% and a pore size of from about 50 mµ to about 40µ.
Claim 57
Dependent Claim
31 words
The membrane of Claim 54 in which said support has a pore volume of from about 20% to about 40% and a pore size of from 100 mµ to about 2µ.
Claim 58
Dependent Claim
14 words
The membrane of Claim 54 in which said support comprises a porous carbon tube.
Claim 59
Dependent Claim
11 words
The membrane of Claim 56 in which said coating comprises zirconia.
Claim 60
Dependent Claim
21 words
The membrane of Claim 56 in which said coating has a particle size of from about 10 to about 30 mµ.
Claim 61
Dependent Claim
13 words
The membrane of Claim 51 in which said coating particles comprise sintered particles.
Claim 62
Dependent Claim
13 words
The membrane of Claim 52 in which said zirconia particles comprise sintered zirconia.
Claim 63
Dependent Claim
13 words
The membrane of Claim 57 in which said zirconia particles comprise sintered zirconia.
References Cited (Backward Citations)
FR2354302A1
Cited
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