As carbon dioxide builds up in the atmosphere, it won’t be enough to simply curb our emissions – we’ll need to actively remove some of what we’ve already released. In a new advance, researchers from Tokyo Metropolitan University have developed a new compound that can reportedly remove carbon dioxide from ambient air with 99 percent efficiency and at least twice as fast as existing systems.
Direct air capture (DAC) technologies usually remove carbon dioxide by piping air or exhaust through some kind of filter or catalyst, including magnetic sponges, zeolite foam or materials made of clay or coffee grounds. Others bubble the air through a liquid, which can either absorb the CO2 or cause it to separate out into solid crystals or flakes.
The new compound falls into that last category, which are known as liquid-solid phase separation systems. While studying a series of liquid amine compounds, the Tokyo Metro team discovered one, called isophorone diamine (IPDA), was particularly effective at capturing carbon dioxide.
In tests, the team found that IPDA was able to remove more than 99 percent of CO2 from air with a concentration of 400 parts per million (ppm) – about the level currently in the atmosphere. This process also happened much faster than other carbon capture techniques, removing 201 millimoles of CO2 per hour, per mole of the compound. That’s at least twice as fast as other DAC lab systems, and far faster than the leading artificial leaf device.
The pollutant separated out into flakes of a solid carbamic acid material, which could be removed from the liquid relatively easily. If need be, it can be converted back into gaseous CO2 by heating it to 60 °C (140 °F), which also releases the original liquid IPDA ready for reuse. Whether the carbon is kept as a solid or a gas, it can then be stored or reused in industrial or chemical processes.
The new system shows promise but, of course, there’s always the question of scale. Humanity belches about 30 billion tons of carbon dioxide into the atmosphere every year, and the world’s largest direct air capture plant currently removes about 4,000 tons a year. It feels a little like bailing water out of a sinking ship with a shot glass.
But still, every glass helps, and the more technologies we have at our disposal for this huge job, the better. And there’s reason for optimism too, as the US Department of Energy has recently announced US$3.5 billion in funding for DAC hubs. Hopefully this kind of attention will encourage some of the more out-there experiments, like using high-altitude balloons or big ponds of algae.
The researchers on the new study are now working on improving the system and investigating how the captured carbon could best be used.
The research was published in the journal ACS Environmental Au.
Source: Tokyo Metropolitan University via Eurekalert
etc etc etc???
Better to reduce emissions and plant a tree/several as well.
+
I hear they do say 'there is this stuff called H2'.
What we should be concentrating on is renewables and the storage systems to make it work. If we have excess generation from that then, fine; use it to remove CO2 from the atmosphere. Otherwise we are just continuing our downward spiral to potential extinction.
Planting trees is not always the answer, as its not the best carbon capture method, and can actually do harm to the environment - Of course that's not the same as stopping the removal of established forests.
These are still early days for CO2 capture and this might only be a shot glass, but its a step in the right direction, although my money is on bio-technology, algae or similar as a possible solution that can easily scale itself.
Why not focus on really practical and risk-free solutions like, restoring forests of Earth, reducing fossil fuel usage, increasing solar/wind/hydro-power (& keep researching better nuclear fission & fusion tech)?
(Which all would have countless side-benefits, besides of saving climate!)
Of course, 1,000 tons of the isophorone would double that to over 400,000 tons of CO2 per year, and then we would be at about 0.001% of annual releases. Get to work Tokyo Metropolitan University! We have to start somewhere