Fluorinated polyolefin membranes for aromatics/saturates separation

• US 5,396,019 A
• Filed: 11/19/1993
• Issued: 03/07/1995
• Est. Priority Date: 08/14/1992
• Status: Expired due to Fees

• Current Assignee: Exxon Research and Engineering Company (Exxon Mobil Corporation)
• Original Assignee: Exxon Research and Engineering Company (Exxon Mobil Corporation)
• Inventors: Noone, Robert E., Sartori, Guido, Ballinger, Bruce H., Ho, Win-Sow W.
• Primary Examiner(s): Sneed, Helen M. S.
• Assistant Examiner(s): GRIFFIN, WALTER DEAN
• Application Number:
  US08/155,446
• Time in Patent Office: 473 Days
• Field of Search: 208/308, 585/818, 585/819, 210/649, 210/650, 210/651, 210/500.36, 210/500.42
• US Class Current: 585/819
• CPC Class Codes: B01D 61/362 Pervaporation
• CPC Class Codes: B01D 71/32 containing fluorine atoms
• CPC Class Codes: B01D 71/34 Polyvinylidene fluoride
• CPC Class Codes: B29C 71/02 Thermal after-treatment B29C71/0063 and B29C71/0072 take precedence
• CPC Class Codes: B29K 2027/12 containing fluorine
• CPC Class Codes: B29L 2031/755 Membranes, diaphragms
• CPC Class Codes: C07C 7/144 using membranes, e.g. selective permeation
• CPC Class Codes: C08J 2327/12 containing fluorine atoms
• CPC Class Codes: C08J 3/247 Heating methods
• CPC Class Codes: C08J 5/2237 containing fluorine
• CPC Class Codes: C10G 31/11 by dialysis

Abstract

The present invention includes the use of crosslinked fluorinated polyolefin membranes membranes for the separation of aromatics from saturates, wherein aromatics can contain sulfur and nitrogen.

Claims

1. A process for the separation of mixtures of aromatics and saturates into aromatics-enriched and saturates-enriched streams comprising:

a) contacting said aromatics/saturates mixture with one side of a crosslinked fluorinated polyolefin membrane at a temperature greater than 100°

C.; and

b) selectively permeating the aromatic components of the mixture through the membrane.

2. A process according to claim 1 wherein said fluorinated polyolefin membrane is crosslinked by heating above about 100°

C. prior to said contacting step or during said contacting step with in situ crosslinking.

3. A process according to claim 1 where said fluorinated polyolefin is a homopolymer, a copolymer of two fluorinated olefins with each other or a copolymer of a fluorinated olefin with an olefin.

4. A process according to claim 3 wherein said homopolymer is polyvinylidenefluoride, polyvinylfluoride, or polytrifluoroethylene.

5. A process according to claim 3 wherein said copolymer is a vinylidenefluoride-hexafluoropropylene copolymer or is an alternating copolymer of ethylene and chlorotrifluoroethylene.

6. A process according to claim 1 wherein said aromatics/saturates mixture is selected from the group consisting of heavy catalytic naphtha boiling in the 140°

-235°

C. range, intermediate catalytic naphtha, boiling in the 93°

-160°

C. range, light aromatics streams boiling in the 40°

-150°

C. range, light catalytic cycle oils boiling in the 200°

-345°

C. range, jet fuel boiling in the 140°

-280°

C. range, diesel boiling in the 200°

-365°

C. range, streams containing benzene, toluene, xylenes, other aromatics, sulfur and nitrogen-containing heteroatom cyclic compounds, saturates, and combinations thereof.

7. The process of claim 1 wherein said feedstream includes sulfur and/or nitrogen.