EP0144097A1
Expired / Lapsed
EP
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A process for the production of crack-free semi-permeable inorganic membranes
Assignee: ECN Netherlands Energy Research Foundation
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Filing: 1984-08-31
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Granted: —
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Expires: 2004-08-31
Abstract
Abstract The membranes are coated on a microporous sintered support of an inorganic oxide and can be used up to a temperature of 900 DEG C while retaining their small pore diameters, e.g. for gas separation. <??>The support having a typical pore-size of from 0.10 mu to 0.50 mu is submerged during 1 to 5 sec.. in a sol containing 0.01% to 25% by weight Boehmite with a preferred particle-size of 3nm to 2 mu , to obtain a membrane layer up to 20 mu . The submerged support is thereafter dried out and heated to a temperature of at least 390 DEG C and the intermediate product may be heated thereafter up to 1500 DEG C. Heating at a temperature of about 500 DEG C during 24 hours is preferred. The sol contains by preference HNO3 or 0.01 to 0.20 mol HClO4 per mol Boehmite and the microporous support is preferred to be d-Al2O3.
Inventors
- 👤 Klaas Keizer
- 👤 Antonie Jan Burggraaf
- 👤 Adriaan Franciscus Maria Leenaars
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 04:02
CPC Classifications
B; B01; B01D; B01D67/00; B01D67/0039; B01D67/0048; B01D71/00; B01D71/02; B01D71/024; B01D71/025; C; C04; C04B; C04B41/00; C04B41/009; C04B41/45; C04B41/50; C04B41/5025; C04B41/80; C04B41/81; C04B41/85; C04B41/87; B01D2323/00; B01D2323/08; B01D2323/081; B01D2323/219; B01D2323/225
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
181 words
A process for the production of dry, crack-free, mechanically and chemically stable, thin, semi-permeable, inorganic membranes by coating a microporous support of sintered inorganic oxides with a suspension of an inorganic-membrane-forming coating material and then heating it, characterized in that inorganic membranes less than 20 µ in thickness are produced by coating a dry microporous inorganic support having a thickness of from 50 µ to 5 and pores with a diameter of up to 5 µ by immersion in a stable sol of colloidal metal oxide- or metal hydroxide particles having a particle size of from 3 nm to 2 µ, the concentration of the dispersed phase whereof ina medium non-solving to the metal oxide- or metal hydroxide particles amounts to from 0.01 to 25% by weight (and preferably from 0.5 to 5% by weight) and where the sol in the boundary layer is first converted to a lyogel, removing the support from the liquid and drying in air to a xerogel with a thickness of fron 1 to 20 µ and then heating to a temperature of at least 390°C.
Claim 2
Dependent Claim
181 words
A process for the production of dry, crack-free, mechanically and chemically stable, thin, semi-permeable, inorganic membranes by coating a microporous support of sintered inorganic oxides with a suspension of an inorganic-membrane-forming coating material and then heating it, characterized in that inorganic membranes less than 20 µ in thickness are produced by coating a dry microporous inorganic support having a thickness of from 50 µ to 5 and pores with a diameter of up to 5 µ by immersion in a stable sol of colloidal metal oxide- or metal hydroxide particles having a particle size of from 3 nm to 2 µ, the concentration of the dispersed phase whereof ina medium non-solving to the metal oxide- or metal hydroxide particles amounts to from 0.01 to 25% by weight (and preferably from 0.5 to 5% by weight) and where the sol in the boundary layer is first converted to a lyogel, removing the support from the liquid and drying in air to a xerogel with a thickness of fron 1 to 20 µ and then heating to a temperature of at least 390°C.
Claim 3
Dependent Claim
20 words
A process according to claim 1, characterized in that α-Al 2 O 3 is rsed as the microporous ceramic support.
Claim 4
Dependent Claim
32 words
A process according to claim 1 or 2, characterized in that a microporous support is used of α-Al 2 O 3 having a typical pore size of from 0.10 µ to 0.50
Claim 5
Dependent Claim
32 words
A process according to any of the claims 1 - 3, characterized in that a microporous ceramic support is used having a typical pore size of from 0.12 µ to 0.34 µ.
Claim 6
Dependent Claim
32 words
A process according to any of the claims 1 - 4, characterized in that a sol is used of Boehmite in water with dispersed particles of from 3 nm to 2 µ.
Claim 7
Dependent Claim
41 words
A process according to any of the claims 1 - 5, characterized in that a sol is used containing from 0.01 to 0.20 mol HClO 4 per mol Boehmite and that the intermediate product is heated at 500°C for 24 hours.
Claim 8
Dependent Claim
41 words
A process according to any of the claims 1 - 6, characterized in that a sol is used containing from 0.03 to 0.11 mol HClO 4 per mol Boehmite and that the intermediate product is heated at 500°C for 24 hours.
Claim 9
Dependent Claim
24 words
A process according to any of the claims 1 - 7, characterized in that a stable Boehmite sol is prepared using HN0 3 .
Claim 10
Dependent Claim
45 words
A process according to any of the claims 1 - 8, characterized in that a sol concentration is used of 3% by weight and that the time of contact between the microporous support and the Boehmite sol is adjusted to from 1 to 5 seconds.
Claim 11
Dependent Claim
27 words
A process according to any of the claims 1 - 9, characterized in that the intermediate product is sintered at a temperature lying between 390°C and 1500°C.
Claim 12
Dependent Claim
115 words
An inorganic membrane less than 20 µ in thickness on a microporous support of α-Al 2 O 3 having a typical pore size of up to 5 µ but preferably 0.10 µ to 0.50 µ, characterized in that the support is immersed for from 1 to 5 seconds but preferably for 2 seconds in a Boehmite sol with dispersed particles of 3 nm to 2 µ, said sol containing HNO 3 or from 0.01 to 0.20 mol HC10 4 per mol Boehmite and having a scl concentration of from 0.01 tc 25% by weight, and that the coated support is then dried and heated to a temperature of at least 390°C and at most 1500°C.
Claim 13
Dependent Claim
115 words
An inorganic membrane less than 20 µ in thickness on a microporous support of α-Al 2 O 3 having a typical pore size of up to 5 µ but preferably 0.10 µ to 0.50 µ, characterized in that the support is immersed for from 1 to 5 seconds but preferably for 2 seconds in a Boehmite sol with dispersed particles of 3 nm to 2 µ, said sol containing HNO 3 or from 0.01 to 0.20 mol HC10 4 per mol Boehmite and having a scl concentration of from 0.01 tc 25% by weight, and that the coated support is then dried and heated to a temperature of at least 390°C and at most 1500°C.
Claim 14
Dependent Claim
22 words
An inorganic membrane produced by the process of any of the claims 1 - 10 and as described and illustrated by examples.
References Cited (Backward Citations)
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