Modified Graphene Oxide-based Membranes for Mixture Separations

A facile method for developing membranes for hydrocarbon mixture separations by depositing graphene oxide flakes on a commercial porous substrate.

Background:

Molecular separations in mixtures account for approximately 50% of industrial energy use in the US alone, so there is high demand for alternate separation technologies, particularly for liquid hydrocarbon separations.  Industrial separation applications require high throughput and permeance for hydrocarbon mixtures, so the membranes must be ultra-thin.  To maintain necessary separation parameters, two-dimensional approaches have been developed in the market, such as this one employing graphene oxide.

Technology Overview:

This University at Buffalo invention presents an innovative fabrication technique for modified graphene oxide membranes for industrial separation applications.  Graphene oxide flakes are deposited onto a commercially available porous support forming hollow fibers, after which it is modified using molecular layer deposition (MLD).  Varying the synthesis conditions generates pore sizes that can be modified for gas or liquid separations.  Development of a proprietary set of growth conditions allows molecules to grow preferentially at the edges of the graphene oxide, preventing molecules from the MLD step from entering the stacked graphene oxide flakes but rather forcing them into the graphene oxide stacks.  This accentuates the separation parameters and the tunability of the membranes for specific applications.  The process is simple and solvent-free, so it is scalable and green.

https://buffalo.technologypublisher.com/files/sites/7583_in-part_image.jpg

Source: background photo, stock.adobe.com/uk/309826747, stock.adobe.com

Advantages:

• The fabrication process is simple and uses no solvent, making it easily scalable and environmentally friendly.
• These membranes are ultrathin, allowing high permeance.
• The rationale design of these membranes allows the exploitation of alternate transport paths in stacked graphene oxide membranes.
• The edge-sealing technique using MLD can be extended to other two-dimensional materials.

Applications:

• Hollow fibers can be formed from the stacked membranes and assembled into modules for organic solvent reverse osmosis applications, separating organic solvent molecules.
• The membranes can be synthesized to generate pore sizes tuned to gas molecule separations.
• Reverse osmosis desalination membranes can also be manufactured using this technology. 

Intellectual Property Summary:

US Provisional Patent Application 63/596,293 filed on November 5, 2023.

Stage of Development:

Laboratory demonstration and analytical analysis.

Licensing Status:

Available for licensing or collaboration.

Relevant links:

• Recent Developments of Graphene Oxide-Based Membranes: A Review (mdpi.com)
• Membranes Coated with Graphene-Based Materials: A Review (mdpi.com)