The Concrete of the Future Captures Carbon Pound for Pound
Updated: Sep 9
Experts say that carbon sequestration is a technology of the distant future. But perhaps this coming attraction has actually arrived.
Jacob Brauer, a biology graduate and rising Master’s student of mechanical engineering at Portland State University, has developed what he believes is the world’s first carbon-negative construction material.
Brauer’s invention is a basalt fiber construction material that sequesters carbon. Competing in this year’s Invent Oregon Collegiate Challenge, he calls it Mafix, and extrapolated across a $1.3 trillion construction market, it suggests the potential for a green revolution in one of the most carbon-intensive sectors of the economy. Mafix could help to close a significant part of the loop in carbon emissions.
“We all share space on this planet. We need to be able to continue to live on this planet,” Brauer said. “There's all these intersectional issues within environmentalism. This is a very fixable thing that is not just a technology problem. This will influence social issues. If you're trying to tackle all these different things, you’ve got to get the industry behind you. You've got to convince people that it's cheaper and it's easier to use. If you can tack on the environmental thing, then that's the success right there.”
In that regard, Mafix sounds too good to be true. Simply put, basalt fiber is a construction material that can replace steel. In its purest form, it’s as strong as titanium. It costs less to make. It requires less energy to produce. It is easier to manipulate at the construction site.
And it can serve a wide variety of functions. It can be plied into rebar to reinforce concrete. It can be added directly to concrete to strengthen it. It can be woven into mats that can be used as a kind of scaffolding. It can be threaded into rockwool that replaces traditional construction insulation.
“You can do anything that needs to be strong tensile strength in construction or high insulation in construction. But with the reinforced polymer material, you can also do anything manufacturing, so you can cast blocks of it.” Brauer pointed to highly specialized research centrifuges.
As a material, basalt fiber is not new. It has been around for about 100 years with varying levels of research and development. In recent years, as industry infrastructure has grown and the regulatory atmosphere has warmed, expectations have warmed as well.
But as pressure mounts to tackle what may be the greatest threat to life on earth, none of the expectations surrounding basalt fiber consider the innovation that Brauer has developed. With Brauer’s chemistry, he can capture carbon dioxide and “fix” it to basalt fiber wherever it is used.
That’s a game-changer, and as far as Brauer knows his team is the only one in the world to be doing this.
“We took this existing material that is expected to have a 200 percent market increase the next 5 years because of the specific material properties that are needed,” Brauer said. “We also have this whole novel chemistry where we've developed this method to make direct deposition of carbon dioxide gas onto the basalt fiber itself to make rock deposit.”
Brauer’s chemistry essentially turns carbon dioxide into baking soda into carbonate rock. “It's a similar process to what they do in Iceland with the CarbFix project,” Brauer said.
In Iceland, CarbFix harvests gigatons of liquified carbon dioxide and injects it into magma underground, where oxides and a couple years’ time mineralize the liquified carbon dioxide into solid carbonate deposits that become part of the rock itself. Theoretically, this sequesters carbon indefinitely.
But beyond the obvious benefit of a carbon commodity, Brauer thinks Mafix has a major advantage. “This is better than doing just liquid CO2 storage because if one of those sinks ruptures, it can explode, it can cause injury to humans and wildlife, and it will leak all of the CO2 back out into the air. But if a rock breaks in half, there's basically no CO2 that gets released.”
Brauer says that Mafix can sequester carbon at a one-to-one ratio of the mass of basalt fiber, which means that the steel substitute sequesters carbon pound for pound.
According to the American Iron and Steel Institute, U.S. demand for steel in 2019 amounted to 112.2 million tons, about 44% of which was used in construction projects. How much of the market Mafix could actually capture is anyone’s guess; Brauer hopes for about 10%.
But supposing that Mafix replaces steel in construction and demand continues to grow at the 2019 rate, Brauer’s basalt fiber substitute has the potential to sequester over 620 million tons of carbon dioxide as rock over 10 years.
Although ambitious, that’s significant. Billed as “the world’s most comprehensive plan to address climate change” that outlines hundreds of climate change mitigation strategies, the Drawdown Review estimates that biochar production, the only carbon sequestration method mentioned in the report, could sequester about 2.2 gigatons of carbon dioxide over 30 years.
Mafix alone could sequester a quarter of that in 10 years, the oft-cited window of time our society has to reverse carbon dioxide-induced climate change.
“We're really pushing to get this thing going because this is the time to do it,” Brauer said. “It's not too late to clean up the environment. And we are actively working towards that.”
But it also isn’t the end of the promise for Mafix.
As a steel rebar substitute that is stronger than steel, basalt fiber is also more elastic, which means it’s easier to tie. That’s important where concrete construction is at times onerous. “It's 90 or 100 degrees and you're down in this concrete pit with all these jagged pieces of rebar. It's dangerous. It takes a lot of time, and there's not enough labor to do that,” Brauer said, pointing to the labor shortage in concrete construction.
Brauer was also quick to note the Cascadia subduction zone earthquake. “You don't have to make the decision of like, well, do I really have enough money to use this nice building material to make sure people are safe?” Brauer said. “It's more like, oh, no, that's cheaper than steel and it will be safe for these earthquakes.”
Brauer’s intellect and enthusiasm are infectious, and it isn’t always easy to keep up. If you sometimes wonder what exactly he’s talking about, you aren’t alone. With Mafix, it seems as though he’s created something that could be extraordinary. Perhaps too extraordinary.
When confronted with something we don’t fully understand, we often rely on faith. While Brauer is quick to trumpet the promise of his basalt fiber, he cannot fabricate with science and statistics the faith of his colleagues.
“I've seen some of the other things he's done,” said Harvey Buckner, a sonic arts engineering student at Portland Community College who helped Brauer develop promotional materials for Mafix. “I believe in him more than anything.”
Cautious optimism is the axiom of the wise, but perhaps we should start believing too. The promise of Mafix speaks for itself, and Brauer’s attitude is very clearly in the right place.
“Anybody can go over and make chlorine and sell chlorine or make rocket fuel and sell rocket fuel and sell these chemicals that, you know, harm the environment,” Brauer said. “But you've got to really work hard to iterate over things until you have something that is environmentally friendly. And that is the correct chemistry you should be using.
“It's like, you know, we all have a responsibility. And some people can choose to ignore it. But I can't.”