ASYMMETRIC HOLLOW FIBER GAS SEPARATION MEMBRANE

• US 20130019748A1
• Filed: 03/30/2011
• Published: 01/24/2013
• Est. Priority Date: 03/30/2010
• Status: Active Grant

• Current Assignee: UBE Corporation
• Original Assignee: UBE Industries Limited
• Inventors: Hisamori, Hiroki, Hayashi, Tatsuya, Morihashi, Seiji, Kanougi, Tomonori
• Granted Patent: US 8,734,568 B2
• Time in Patent Office: Days
• US Class Current: 95/47
• CPC Class Codes: B01D 2256/12 Oxygen
• CPC Class Codes: B01D 2257/102 Nitrogen
• CPC Class Codes: B01D 2325/022 Asymmetric membranes
• CPC Class Codes: B01D 53/228 characterised by specific membranes
• CPC Class Codes: B01D 69/02 characterised by their properties
• CPC Class Codes: B01D 69/08 Hollow fibre membranes manufacture of hollow fibres D01D5/24, D01F1/08
• CPC Class Codes: B01D 71/64 Polyimides; Polyamide-imides; Polyester-imides; Polyamide acids or similar polyimide precursors
• CPC Class Codes: C01B 13/0255 characterised by the type of membrane

Abstract

The present invention relates to an asymmetric hollow fiber membrane for gas separation made of a soluble aromatic polyimide, wherein an orientation index is 1.3 or less, a separation coefficient α(P′O₂/P′N₂) as a permeation rate ratio of oxygen gas/nitrogen gas at 40° C. is 5.3 or more, and a tensile fracture elongation is 15% or more.

Claims

1. An asymmetric hollow fiber membrane for gas separation made of a soluble aromatic polyimide, wherein

an orientation index is 1.3 or less,

a separation coefficient α

(P′

O₂/P′

N₂) which represents a ratio of permeation rate of oxygen gas and nitrogen gas at 40°

C. is 5.3 or more, and

a tensile elongation at break is 15% or more.

2. The asymmetric hollow fiber membrane for gas separation according to claim 1, wherein an oxygen gas permeation rate P′

O₂ at 40°

C. is 6.0×

10<sup>−

5</sup> cm³ (STP)/cm²·

sec·

cmHg or more.

3. The asymmetric hollow fiber membrane for gas separation according to claim 1, wherein the soluble aromatic polyimide comprises a repeating unit represented by general formula (1).

4. A process for selectively separating and collecting a particular gas from a mixed gas containing a plurality of gases by using the asymmetric hollow fiber membrane for gas separation according to claim 1.

5. A process for producing an oxygen-rich air or nitrogen-rich air from the air by using the asymmetric hollow fiber membrane for gas separation according to claim 1.