Anisotropic membranes for gas separation

Patent · Wed Dec 31 23:00:00 EST 1986

OSTI ID:866312

Gollan, Arye Z ^[1]

---

1. Newton, MA

A gas separation membrane has a dense separating layer about 10,000 Angstroms or less thick and a porous support layer 10 to 400 microns thick that is an integral unit with gradually and continuously decreasing pore size from the base of the support layer to the surface of the thin separating layer and is made from a casting solution comprising ethyl cellulose and ethyl cellulose-based blends, typically greater than 47.5 ethoxyl content ethyl cellulose blended with compatible second polymers, such as nitrocellulose. The polymer content of the casting solution is from about 10% to about 35% by weight of the total solution with up to about 50% of this polymer weight a compatible second polymer to the ethyl cellulose in a volatile solvent such as isopropanol, methylacetate, methanol, ethanol, and acetone. Typical nonsolvents for the casting solutions include water and formamide. The casting solution is cast in air from about zero to 10 seconds to allow the volatile solvent to evaporate and then quenched in a coagulation bath, typically water, at a temperature of 7.degree.-25.degree. C. and then air dried at ambient temperature, typically 10.degree.-30.degree. C.

• Research Organization: A/G Technology Corp
• DOE Contract Number: AC07-83ID12429
• Assignee: A/G Technology Corporation (Needham, MA)
• Patent Number(s): US 4681605
• OSTI ID: 866312
• Country of Publication: United States
• Language: English

Related Subjects

-25
-30
/96/210/264/
000
10
35
400
47
50
acetone
air
air dried
allow
ambient
ambient temperature
angstroms
anisotropic
anisotropic membranes
base
bath
blended
blends
cast
casting
casting solution
cellulose
cellulose-based
coagulation
compatible
comprising
content
continuously
decreasing
degree
dense
dried
ethanol
ethoxyl
ethyl
ethyl cellulose
evaporate
formamide
gas
gas separation
gradually
integral
integral unit
isopropanol
layer
membrane
membranes
methanol
methylacetate
microns
microns thick
nitrocellulose
nonsolvents
polymer
polymers
pore
pore size
porous
porous support
quenched
separating
separation
separation membrane
size
solution
solution comprising
solutions
solvent
support
support layer
surface
temperature
thick
total
typical
typically
typically water
unit
volatile
volatile solvent
water
weight
zero