Researchers from Tokyo Metropolitan University have developed a new compound that they claim is 99% efficient in removing CO2 from the atmosphere. The new system is also reportedly two times faster than existing ones.
Some direct air capture (DAC) technologies remove CO2 by piping air or waste gases through a filter or catalyzer. Others use liquid to either absorb the carbon or turn it into a solid mass. The new compound, called isophorone diamine (IPDA), falls in the latter category, also known as liquid-solid phase separation systems.
The Tokyo Metropolitan University found out that IPDA could remove over 99% of carbon dioxide from ambient air with a concentration of 400 parts per million, which is around as much as there currently is in ambient air. The process is also twice faster than other lab systems and much faster than the “artificial leaf” device: IPDA removes 201 millimoles of carbon hourly.
With the new direct air capture technology, the contaminant is separated into flakes of a solid carbamic acid material. After it is removed from the liquid – which happens relatively easy – the carbon can be turned back into gassy carbon by heating it to 60 °C, and the IPDA is ready to be reused. The CO2 can then be stored or sold to the industry.
One issue that remains with the new system is the question of scalability. While 30 billion tons of CO2 are released into the air annually, the largest DAC plant removes only about 4,000 tons per year.
The good news is that the US Department of Energy recently announced it will provide $3.5 billion in funding for hubs for direct air capture. Such investments are key to encouraging the development of new solutions for the climate crisis.
Tokyo researchers are now looking for ways to improve the direct air capture technology and find the best carbon storage options.