Oxidatively Stable Carrier Membranes for Gas Separation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing selectively permeable polymeric membranes used for gas separation, such as hydrogen purification and carbon dioxide sequestration, are readily oxidized when contacted with air at elevated temperatures, making them unsuitable for many industrial applications.

Innovation Solution

Development of membranes with a support layer and a selective polymer layer comprising an oxidatively stable carrier, such as quaternary ammonium hydroxide or fluoride, dispersed within a hydrophilic polymer matrix, which exhibits selective permeability and oxidative stability at temperatures above 100°C, allowing the use of air as a sweep gas.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If existing selectively permeable polymeric membranes are used for gas separation, then gas separation functionality is achieved, but the membranes are readily oxidized when contacted with air at elevated temperatures

Engineering Contradiction:

Improveoxidative stabilityVSAvoidoxidation damage

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent employs composite material construction by combining a support layer made of conventional polymeric material with a selective layer comprising oxidatively stable carriers (quaternary ammonium hydroxide or fluoride) dispersed in a hydrophilic polymer matrix. This composite structure allows the membrane to maintain gas separation functionality while achieving resistance to oxidation when contacted with air at elevated temperatures, directly resolving the technical contradiction between gas separation performance and oxidative stability.

Inventive Principle:

Principle #40Composite materials

2Productivity

If conventional polymeric membranes are used at elevated temperatures with air sweep gas, then process efficiency is improved, but membrane degradation occurs due to oxidation

Engineering Contradiction:

Improvegas separation efficiencyVSAvoidmembrane service life

Core Design Contradiction:

ProductivityVSDuration of action of stationary object

Solution Approach 1:

The patent changes the chemical composition parameters of the selective layer by incorporating oxidatively stable carriers (quaternary ammonium hydroxide or fluoride) with specific chemical structures that resist oxidation. This parameter change in material composition enables the membrane to maintain its gas separation efficiency and structural integrity at elevated temperatures when contacted with air sweep gas, thereby extending membrane service life while preserving productivity.

Inventive Principle:

Principle #35Parameter changes

3Power

If air is used as sweep gas at temperatures above 100°C, then process performance is enhanced, but existing membranes undergo oxidative degradation

Engineering Contradiction:

Improveprocess performanceVSAvoidmembrane stability

Core Design Contradiction:

PowerVSReliability

Solution Approach 1:

The patent employs quaternary ammonium hydroxide or fluoride carriers which are chemically stable and resistant to oxidation, allowing the use of air as sweep gas at elevated temperatures without membrane degradation. These carriers act as stable, reusable components that maintain membrane functionality under harsh oxidative conditions, enabling enhanced process performance with air sweep gas while ensuring long-term membrane stability.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The membranes demonstrate stable performance and selective permeability for gases like carbon dioxide and hydrogen sulfide, maintaining CO2/H2 selectivity and permeance over extended periods at elevated temperatures, enabling their use in industrial gas separation processes.

Implementation Method 1

The selective polymer layer can comprise an oxidatively stable carrier dispersed within a hydrophilic polymer matrix... The membranes can exhibit selective permeability to gases. For example, the membranes can be used to selectively remove carbon dioxide and/or hydrogen sulfide from hydrogen and/or nitrogen.

Methodology Applied

Scientific EffectFacilitated transport:

Implementation Method 2

The selective polymer layer can comprise an oxidatively stable carrier dispersed within a hydrophilic polymer matrix... The membranes can exhibit selective permeability to gases.

Methodology Applied

Scientific EffectDiffusion: Diffusion

Data Source

PatentUS10213747B2Membranes for gas separation

Publication Date: 2019.02.26 OHIO STATE INNOVATION FOUND

AI summary

Membranes, methods of making the membranes, and methods of using the membranes are described. The membranes can comprise a support layer, and a selective polymer layer disposed on the support layer. The selective polymer layer can comprise an oxidatively stable carrier dispersed within a hydrophilic polymer matrix. The oxidatively stable carrier can be chosen from a quaternary ammonium hydroxide carrier (e.g., a mobile carrier such as a small molecule quaternary ammonium hydroxide, or a fixed carrier such as a quaternary ammonium hydroxide-containing polymer), a quaternary ammonium fluoride carrier (e.g., a mobile carrier such as a small molecule quaternary ammonium fluoride, or a fixed carrier such as a quaternary ammonium fluoride-containing polymer), and combinations thereof. The membranes can exhibit selective permeability to gases. The membranes can selectively remove carbon dioxide and/or hydrogen sulfide from hydrogen and/or nitrogen. Further, the membranes can exhibit oxidative stability at temperatures above 100° C.