MANUFACTURING CARBON MOLECULAR SIEVE MEMBRANES USING A PYROLYSIS ATMOSPHERE COMPRISING SULFUR-CONTAINING COMPOUNDS

• US 20160184776A1
• Filed: 05/29/2015
• Published: 06/30/2016
• Est. Priority Date: 12/31/2014
• Status: Abandoned Application

• Current Assignee: L'Air Liquide Societe Anonyme Pour L'Etude et L'Exploitation Des Procedes Georges Claude (L'Air Liquide SA)
• Original Assignee: L'Air Liquide Societe Anonyme Pour L'Etude et L'Exploitation Des Procedes Georges Claude (L'Air Liquide SA)
• Inventors: CHEVREL, Henri, JURCIK, Benjamin J. Jr.
• Application Number:
  US14/725,987
• Publication Number:
  US 20160184776A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B01D 2256/12 Oxygen
• CPC Class Codes: B01D 2256/16 Hydrogen
• CPC Class Codes: B01D 2256/245 Methane
• CPC Class Codes: B01D 2257/102 Nitrogen
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 53/228 characterised by specific membranes
• CPC Class Codes: B01D 67/0067 by carbonisation or pyrolysis
• CPC Class Codes: B01D 71/021 Carbon
• CPC Class Codes: B01D 71/028 Molecular sieves carbon B01D71/021
• CPC Class Codes: B01D 71/64 Polyimides; Polyamide-imides; Polyester-imides; Polyamide acids or similar polyimide precursors
• CPC Class Codes: B29C 35/00 Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor moulds with incorporated heating or cooling means B29C33/02 ; thermal after-treatment of shaped articles B29C71/02; curing devices for plastics dental prostheses A61C13/14; before moulding B29B13/00
• CPC Class Codes: B29L 2007/001 having irregular or rough surfaces treads for tyres B29L2030/002
• CPC Class Codes: B29L 2031/14 Filters optical filters B29L2011/0066, sieves or screens B29L2031/737
• CPC Class Codes: Y02C 20/40 of CO2

Abstract

A carbon molecular sieve (CMS) membrane is made by pyrolyzing a polymeric precursor membrane in a pyrolysis atmosphere containing a sulfur-containing compound.

Claims

1. A method for producing a CMS membrane, comprising the steps of:

forming a polymeric precursor membrane; and

pyrolyzing the polymeric precursor membrane in a pyrolysis atmosphere containing 5 ppm (vol/vol) to 50% (vol/vol) of an sulfur-containing compound in a balance of inert gas.

2. The method of claim 1, wherein the sulfur-containing compound is selected from the group consisting of H₂S, COS, CS₂, SO₂, and benzyl disulfide.

3. The method of claim 1, wherein the balance gas is N₂, Ar or mixtures thereof.

4. The method of claim 1, wherein the polymeric precursor membrane comprises a separation layer, the separation layer comprising 6FDA:

BPDA/DAM.

5. The method of claim 1, wherein the pyrolysis is conducted at a pressure of 0.25-1.0 bar (abs).

6. The method of claim 1, wherein the polymeric precursor membrane comprises a polyimide comprising alternating units of diamine-derived units and of dianhydride-derived units having the structure of formula I,

7. A CMS membrane produced according to the method of claim 1.

8. A method for separating a gas mixture, comprising the steps of feeding the gas mixture to the CMS membrane of claim 7, withdrawing a permeate gas from a permeate outlet of the CMS membrane, and withdrawing a non-permeate gas from a non-permeate outlet of the CMS membrane that is deficient in at least one gas relative to the gas mixture.