Back to results
US 12,673,298 B1Granted
Fluid separation membranes and use thereof
AssigneeSemicom Dwc-LLC
InventorBenjamin Bikson
Life of this patent
Estimating the term…
Abstract
A process is disclosed for the production of highly asymmetric hollow fibers suitable for use as permselective gas separation membranes and for the fabrication of composite membranes derived from polyetherimide. The resulting polyetherimide membranes exhibit superior selectivity and permeability characteristics and are particularly advantageous for the separation of carbon dioxide from natural gas, biogas, and other gas streams containing acid gases.
Claims22
A hollow fiber comprising a polymer composition comprising a blend of polyetherimide (PEI) and a compatible polyimide, said hollow fiber produced by a method comprising the steps of:
- (i) forming a spinning solution comprised of polyetherimide (PEI) or a blend of polyetherimide with a compatible polyimide in a mixture of an aprotic solvent and glycol ether non-solvent;
- (ii) extruding said spinning solution through a spinneret to form a nascent hollow fiber while injecting a bore fluid;
- (iii) passing the nascent hollow fiber through an air gap;
- (iv) passing the nascent hollow fiber through a coagulation bath to solidify the hollow fiber;
- (v) washing the hollow fiber to remove solvent and non-solvent, and
- (vi) collecting the solidified hollow fiber,
- wherein the polyimide is a condensation polymer of dianhydride and diamine of the following formulae:
- or a polyimide derived from aromatic dianhydrides and aromatic diisocyanates based on a 3,3′4,4′-benzophenone tetracarboxylic dianhydride and 80% methylphenylene-diamine+20% methylene diamine co-polyimide precursor (BTDA-TDI/MDI).
5 more elements
Dependencies are inferred from the claim text.