Researchers led by Newcastle University have pioneered a novel humidity-driven membrane that captures carbon dioxide from the air, a crucial step toward combating climate change. The membrane’s design leverages natural humidity, reducing energy consumption and enabling sustainable carbon capture.
A groundbreaking innovation from a consortium of top universities promises to revolutionize the field of carbon capture, leveraging natural humidity differences to extract carbon dioxide (CO2) from the air with unprecedented efficiency and reduced energy consumption. This innovation is poised to significantly contribute to efforts to mitigate climate change.
The new synthetic membrane is the brainchild of researchers from Newcastle University, alongside colleagues from Victoria University of Wellington, Imperial College London, Oxford University, Strathclyde University and University College London. Their research, published in the journal Nature Energy, tackles the immense challenge of direct air capture (DAC) of CO2, a critical need identified among the “Seven chemical separations to change the world.”
“Dilute separation processes are the most challenging separations to perform for two key reasons. First, due to the low concentration, the kinetics (speed) of chemical reactions targeting the removal of the dilute component are very slow. Second, concentrating the dilute component requires a lot of energy,” Ian Metcalfe, the Royal Academy of Engineering Chair in Emerging Technologies at Newcastle University and the study’s lead investigator, said in a news release.
The innovative membrane utilizes naturally occurring humidity differences as a driving force, thereby overcoming the significant energy demand typically associated with these processes. Additionally, the presence of water accelerates the transport of CO2 through the membrane, tackling the kinetic challenge.
“Direct air capture will be a key component of the energy system of the future. It will be needed to capture the emissions from mobile, distributed sources of carbon dioxide that cannot easily be decarbonized in other ways,” added Greg A. Mutch, a Royal Academy of Engineering Fellow in the School of Engineering at Newcastle University.
Mutch likened the process to a water wheel on a flour mill, using the downhill transport of water to pump CO2 out of the air.
The membrane has shown promising results under varying humidity conditions, spontaneously pumping CO2 into an output stream when the humidity was higher on the output side. Advanced techniques like X-ray micro-computed tomography were used to characterize the membrane’s structure precisely. On the molecular scale, density-functional-theory calculations identified unique “carriers” within the membrane that transport both CO2 and water, ensuring their efficient release and capture.
This effort, described as a “real team effort over several years” by Metcalfe in the news release, highlights the collaborative nature of modern scientific breakthroughs. The work received substantial support from the Royal Academy of Engineering and the Engineering & Physical Sciences Research Council, reinforcing the importance of interdisciplinary cooperation in tackling global challenges.
The implications of this breakthrough extend far beyond the lab. As the world moves towards a circular economy, direct air capture technologies like this one will play a crucial role in capturing emissions from hard-to-decarbonize sources. This innovation not only supports climate targets such as the 1.5 degrees Celsius goal set by the Paris Agreement but also provides a sustainable method for generating carbon-neutral or even carbon-negative hydrocarbon products.
The researchers’ pioneering work paves the way for more energy-efficient and scalable carbon capture solutions, offering a beacon of hope in the fight against climate change.