Systems and methods for using a boehmite bond-coat with polyimide membranes for gas separation

Abstract

The subject matter disclosed herein relates to gas separation membranes and, more specifically, to polyimide gas separation membranes. In an embodiment, a gas separation membrane includes a porous substrate, a substantially continuous polyimide membrane layer, and one or more layers of boehmite nanoparticles disposed between the porous substrate and the polyimide membrane layer to form a bond-coat layer. The bond-coat layer is configured to improve the adhesion of the polyimide membrane layer to the porous substrate, and the polyimide membrane layer has a thickness approximately 100 nm or less.

Description

BACKGROUND OF THE INVENTION[0001]The subject matter disclosed herein relates to gas separation membranes and, more specifically, to polyimide gas separation membranes.[0002]One method of purifying a gas mixture is through the use of a gas separation membrane. In general, a gas separation membrane relies upon a partial pressure differential across a porous membrane material to selectively drive gas molecules across the membrane. For a gas separation membrane to be effective, the membrane should have a sufficiently high permeance and high selectivity. Permeance is a measure of how easily a particular gas flows across the membrane, while selectivity is a measure of how much more of one component of the gas mixture (e.g., hydrogen) crosses the membrane compared to a second component of the gas mixture (e.g., carbon dioxide). Generally, as the permeance of a membrane increases, the selectivity of the membrane is reduced, making a selective membrane with a high throughput difficult to ach...

AI Technical Summary

Benefits of technology

The patent describes a new type of gas separation membrane that consists of a porous layer, a layer of boehmite nanoparticles, and a layer of polyimide membrane. This membrane has been found to improve the adhesion between the polyimide membrane layer and the porous layer, with the polyimide membrane layer being very thin. The membrane's unique structure allows for efficient gas separation, and its thickness is much thinner than typical commercial membranes. This patent also describes a method for manufacturing this membrane and a membrane that includes a support layer, an intermediate layer, and a bond-coat layer for increased gas separation efficiency.

Problems solved by technology

Generally, as the permeance of a membrane increases, the selectivity of the membrane is reduced, making a selective membrane with a high throughput difficult to achieve.

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