Mazda is experimenting with a carbon-capture system that can trap a portion of tailpipe emissions directly from a running engine – technology the company says could make combustion cars significantly cleaner while electric vehicles remain dependent on fossil-fuelled power grids.
Speaking to Australian journalists at this week’s Tokyo motor show, Mazda CFO Jeff Guyton revealed the company has developed a prototype exhaust-mounted capture device that can store about 20 per cent of a vehicle’s carbon dioxide output in a dedicated tank.
“The exhaust from an engine is really CO2-rich. It’s a target-rich environment to grab CO2 from,” Mr Guyton said.
“In the vehicle environment… we can then capture that carbon and be able to use it. Maybe it’s an exchange. Maybe, when you fuel the car, you exchange a filter or a substrate, and that thing — maybe that CO2 — is something which you can sell.”
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Mazda plans to test the technology publicly in an endurance racing car later this year, collecting data under full-load conditions before deciding whether it could be scaled for road use.
“We are developing the tech, but what we have prototyped so far is very promising, and we are going to be demonstrating that in an endurance race later this year… we’ll get data from that race car during racing conditions,” he said.
According to Mr Guyton, the system captures around one-fifth of emitted CO2 by drawing exhaust gases through a drying process and binding the carbon to a crystalline zeolite substrate.
“You have hot exhaust gas coming through the pipe… the system sucks away a portion of what’s going out the tailpipe. It dries it, so that there’s basically CO2 left, and then there’s a kind of crystalline structure in our prototype made of zeolite… about 20 per cent of the CO2 that would otherwise go out stays in the device.”

While Mazda hasn’t disclosed when or if the technology will reach production, the concept points to a different path for cutting vehicle emissions – one that could extend the life of internal-combustion engines even as electric vehicles (EVs) gain political backing.
The captured gas is stored in a small onboard tank, which would eventually need to be swapped or emptied. Mazda says the spent CO2 could potentially be repurposed as a raw material for recycled plastics or industrial processes.
Mr Guyton suggested the company’s early work with carbon-based composite materials showcased at Tokyo in the Vision X-Coupe concept could link directly with this research.

“Those black parts are made with recycled carbon, not from our carbon-capture device, but could be someday, maybe. That black moulding is a very unique plastic that’s made from recycled carbon,” he said.
It’s a typically Mazda-style innovation: small-scale, pragmatic, and focused on incremental real-world benefits rather than sweeping promises. Mr Guyton admitted the company doesn’t have the resources to chase every new technology at once.
“It’s not big. I mean, we’re a small company, true. So our mindset is, Mazda can do anything, we just can’t do everything all at once,” he said.
For Australia, where Mazda remains a top-three brand by sales but offers limited electrification, this sort of development reinforces its cautious approach to zero-emissions motoring. While competitors roll out full battery line-ups to meet the New Vehicle Efficiency Standard (NVES), Mazda continues to invest in technologies that aim to clean up petrol engines rather than replace them entirely.

The carbon-capture prototype forms part of Mazda’s wider “Multi-Solution Strategy”, which also includes plug-in hybrids, rotary-range extenders, and experiments with biofuels. Mr Guyton argues that if such innovations can be made affordable and scalable, they could help existing vehicles (not just new EVs) cut their net emissions.
It’s an idea that may not fit the political narrative but could prove more achievable in markets like Australia, where energy generation is still far from carbon-neutral and EV infrastructure remains patchy.
Mazda’s next challenge will be to prove the system can function reliably in mass-market cars without adding excessive cost or weight.
For now, it remains an ambitious laboratory experiment, one that captures the company’s determination to make internal-combustion technology part of a cleaner future, rather than a casualty of regulation.
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