Process for making hollow fiber mixed matrix membranes
AssigneeL'Air Liquide, Societe Anonyme a Directoire et Conseil de Surveillance pour l'Etude et l'Exploitation des Procedes Georges Claude
InventorsOkan Max Ekiner, Sudhir S. Kulkarni
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Abstract
Isopycnic or asymmetric mixed matrix hollow fiber membranes for gas separation can be made by a continuous spinning process. Mixed matrix membranes are characterized by a continuous phase of selectively gas permeable polymer in which are uniformly dispersed discrete absorbent particles such as molecular sieves that also have selectivity enhancing properties. The fibers can be monolithic in which the fiber wall is entirely mixed matrix, or composite in which an active mixed matrix layer is positioned adjacent to a supporting substrate layer. The novel mixed matrix hollow fiber membranes provide higher selectivity than dense film membranes of the continuous phase polymer.
Claims11
A process for making mixed matrix hollow fiber membrane for gas separation comprising,
- (A) providing a spinnerette adapted to extrude at least one nascent hollow fiber,
- (B) feeding a bore fluid through the spinnerette to form a cylindrical fluid stream for each hollow fiber,
- (C) feeding through the spinnerette to an annular channel surrounding the fluid stream for each hollow fiber a suspension comprising molecular sieve particles uniformly dispersed in a polymer solution comprising a selectively gas permeable polymer and a solvent for the selectively gas permeable polymer,
- (D) immersing the nascent hollow fiber in a coagulant for a duration effective to solidify the selectively gas permeable polymer, thereby forming a monolithic mixed matrix membrane hollow fiber, and
- (E) drawing the nascent hollow fiber at a draw ratio in the range of about 1-10.
Dependencies are inferred from the claim text.