The industrial sector is well known for producing ample greenhouse gasses contributing to global warming and climate change. However, as the world eagerly seeks solutions for reducing its carbon footprint, developments in membrane technology for carbon capture have proved invaluable.

Why Use Membrane Technology for Carbon Capture?

Membrane technology is crucial to decarbonizing industrial operations and energy generation. It uses various barriers to separate carbon dioxide (CO2) emissions from other gasses, such as nitrogen and oxygen, for storage.

For instance, the chemical manufacturing industry reported 186 million metric tons of CO2 equivalent in 2022 — a 6% increase from 2013. Meanwhile, just one ton of cement produces 0.8-0.9 tons of CO2, accounting for 8% of the global CO2 emissions.

The latest absorption technologies are energy-efficient and easier to scale up for larger applications than other methods. Membrane gas separation processes also have a 40%-60% lower environmental impact and do not require harmful chemicals.

Emerging Designs and Configurations

Advancing designs and configurations in membrane technology seek to enhance efficiency, selectivity and resilience in carbon capture and storage. For example, hollow fiber improves gas-liquid flow with a 40%-50% absorption of flue gas.

Likewise, in a pilot study funded by the U.S. Department of Energy, thin-film composite membranes have effectively captured 99% of CO2 with 95% purity from cement industrial emissions and power plants. According to the scientists, the captured CO2 may be stored belowground, used to reinforce concrete or added to products.

Another configuration development is hybrid systems, which integrate membranes with other carbon capture processes for greater efficiency. These technologies may include absorption, adsorption and cryogenics. For example, membrane-cryogenic hybrid methods achieve 86% CO2 recovery and 90% purity with low energy inputs.

Meanwhile, power plants may benefit from smart membranes — sensors and other adaptive mechanisms — enabling modified membrane designs for operational efficiency in real-time.

Developments in Membrane Materials

Membrane materials themselves have also undergone significant breakthroughs for improved CO2 separation and performance. While polymer-based membranes have been the preferred material in the past, they have several limitations.

The National Energy Technology Laboratory’s Point Source Carbon Capture Program is making strides in capturing CO2 with permeable and semi-permeable materials, improving their resistance to thermal and physical changes, ability to withstand gaseous contaminants and integration into hybrid systems.

Some of the more recent material advancements include:

• Polymer nanocomposites: Newer polymer membranes comprising inorganic nanoparticles and organic polymer matrices for better gas permeability.
• Metal-organic frameworks: Highly porous materials with effective CO2 and nitrogen separation.
• Ceramic membranes: Derived from inorganic materials like zirconia and alumina with high corrosion resistance and thermal resilience.
• Ionic liquid-based membranes: Utilize liquid salts to form a polymer and improve CO2 solubility and selectivity.
• Biomimetic mineralization: Mimics natural processes like photosynthesis to capture and convert CO2 into stable materials.

Challenges for Future Membrane-Based Carbon Capture

Although advances in membrane technology for carbon capture are compelling, there is still room for improvement. Researchers must continue developing membrane materials for high selectivity and permeability — as of now, this remains a serious challenge.

Some materials are unable to withstand harsh environments. For example, high temperatures, pressure or chemicals may degrade, evaporate or lower the performance of specific membranes.

Membrane fouling is another critical issue — an accumulation of unwanted surface materials on the membrane, decreasing its ability to capture CO2 effectively. Scientists from MIT may have solved this problem by coating the flue gas output at power plants with algae. Marine algae sequester 50% of global CO2 and contain proteins and minerals capable of absorbing other gasses present in carbon capture.

Advancing Membrane Technology a Catalyst for Future Carbon Capture

The developments in membrane technology are revolutionizing carbon capture across the industrial and energy sectors. From the latest configurations to new membrane materials, its progress indicates a viable solution to mitigating greenhouse gas emissions.