Gas Separation Gets Flexible

Gas separation is essential for industries, from medical applications like extracting nitrogen and oxygen to carbon capture and natural gas purification. Traditional methods, such as cooling air to separate oxygen and nitrogen, are energy-intensive and costly. Most gas separation processes rely on porous materials specific to certain gases, which limits their versatility.

Recently, Wei Zhang and his team at the University of Colorado Boulder published research in Science on a new porous material that reduces energy costs and accommodates various gases. This material, made from common substances, combines rigidity and flexibility, allowing it to adjust pore sizes by changing temperature. Most gases can pass through at room temperature, but increasing the temperature reduces the pore size, selectively allowing only “smaller” gases.

The new material, similar to zeolite, uses dynamic covalent chemistry focusing on the reversible boron-oxygen bond. This bond enables self-correcting behavior and structural order. Developing the material was challenging, especially understanding its structure and properties, but studying its small-molecule model system helped overcome these difficulties.

Zhang highlights the material’s scalability and industrial potential, as it is made from commercially available, inexpensive building blocks. His team is seeking a patent and exploring further research with other materials. Zhang envisions this technology as a sustainable solution for industrial gas separation needs, with potential applications in membrane-based systems.