At first glance, the small conference room inside Chattanooga startup incubator Brickyard looks too cramped to sustain Daniel Rau’s ambitions.
But for a stretch of time, it was also where he slept.
Rau gestures toward a cushioned bench tucked against a wall, laughing at the memory.
“I used to sleep on this,” the 23-year-old Vanderbilt University graduate from Chicago says. “I’m not proud of it, and while I hope those days are behind me, we still keep a few beds and a couch in our laboratories on Amnicola Highway – something OSHA probably wouldn’t be thrilled about.”
Rau says he normally runs on four hours of sleep and speaks about mining, chemistry and critical minerals with what amounts to casual certainty, considering he’s essentially outlining a moonshot.
From the low-slung industrial offices of Brickyard, and later from industrial space across from BASF’s Chattanooga operations, Rau has been building Kunin. The startup is trying to reinvent one of the invisible but essential industrial processes behind modern life: the separation and refinement of metals.
If the company succeeds, Rau believes Kunin could help lower the cost of producing critical minerals needed for semiconductors, electric vehicles and artificial intelligence infrastructure while also reducing mining waste and helping the United States compete with China in mineral processing.
The ambition is enormous, Rau says, but so is the scale of the market. “It’s a technology that should exist. Moving forward, the world is going to need metals produced at a lower cost, and someone has to figure out how to do that.”
The ‘messy middle’ of mining
To understand Kunin, Rau says, it helps to start with “Mining 101.”
A mining company digs ore from the ground. That ore contains a variety of metals bound together in mineral structures. The rock is crushed into powder, acid is introduced and the metals dissolve into liquid.
What remains is what Rau calls an “alphabet soup” – a harsh chemical mixture filled with valuable metals and impurities.
The challenge is separating those materials efficiently and economically.
“We have to take this highly impure alphabet soup and turn it into a very pure liquid,” Rau says. “So we use a range of chemical engineering techniques to transform a liquid that’s – for example – 1% copper and 99% impurities into one that’s more than 30% copper and, ideally, less than 1% impurities.”
Kunin focuses on that separation stage – what Rau calls the “messy middle” between impure and pure materials.
Specifically, the company is innovating around ion exchange, a long-established technology that uses chemically engineered materials to selectively pull certain metals out of liquid solutions.
Traditional ion exchange systems rely on tiny polymer resin beads. Kunin’s approach centers on a new form factor and manufacturing method designed to speed up metal extraction while using significantly less material.
“We’ve proven that our process delivers faster, higher-capacity separation, which means you need about 20 times less material,” Rau says.
The company is named after Dr. Robert Kunin, one of the early pioneers of ion exchange technology who worked at Oak Ridge during the Manhattan Project.
For Rau, the implications stretch far beyond mining.
“The nerdy side of me would love to eventually replace the ion exchange resin bead entirely,” he says. “That technology is used everywhere – water treatment, pharmaceutical separations, food and beverage processing, pulp and paper processing. It’s a $20 billion market.”
Failed startup, second beginning
Kunin emerged from a setback. As Rau neared graduation from Vanderbilt in 2024 with a chemical engineering degree, he tried launching a lithium extraction startup connected to research a professor developed.
The opportunity came together quickly, with grants following and momentum building.
“With a month left in school, I made a blind decision to pursue the startup instead of going into industry full time as a chemical engineer,” Rau says. “We gave ourselves six months to see if we could advance the technology and raise venture capital around it.”
It looked promising for a while. Then came the discovery that another startup emerging from MIT had already patented nearly identical technology.
“They’d raised about $12 million and already launched, and their patent had been awarded,” Rau says. “At that point, I decided it wasn’t worth pursuing, even though I’d already invested a lot of time and resources into it.”
The collapse of that venture forced Rau to immerse himself in the broader economics and engineering of mining and mineral processing. Instead of walking away from the industry, he began looking for a different technological gap.
That search led directly to Kunin.
“What this means for mining operations is cheaper separations,” Rau says. “In practical terms, it means many of the niche metals this country is forced to import can be produced economically again.”
Why critical minerals suddenly matter
For decades, mining technology and mineral processing attracted relatively little public attention in the United States.
That has changed rapidly.
The rise of electric vehicles, data centers, semiconductors, renewable energy infrastructure and advanced defense technologies has fueled growing concern over America’s dependence on foreign supply chains for critical minerals such as gallium, germanium, cobalt and rare earth elements.
“For many of these metals, China controls roughly 90% of the market because of its processing technology and financial approach to mining,” Rau says. “They’ve done an exceptional job of recovering every possible metal from the ore they process.”
Rau argues many Western mines focus only on extracting the primary commodity while discarding other valuable metals contained in the same ore body. Kunin’s technology aims to change that equation by making it economically viable to recover more of those byproduct minerals.
“We’re actively working on gallium and germanium projects with the Department of Energy and, under confidentiality agreements, on projects involving gallium, germanium, cobalt, precious metals and rare earth elements with companies around the world.”
Kunin’s vision extends beyond efficiency and profit margins into geopolitics and national security.
Even Silicon Valley investors, Rau says, are beginning to recognize the strategic implications.
“With the boom in AI and data centers, companies are starting to realize they can’t source some of these niche metals in the United States because we don’t produce them domestically,” he says. “Others are recognizing that if their multibillion-dollar technology ambitions succeed, there might not even be enough supply of certain metals to support them.”
Rau argues the United States largely abandoned much of its mining innovation infrastructure decades ago. He points to the closure of the U.S. Bureau of Mines in 1996 and the long decline of mining engineering programs, many of which either disappeared entirely or now operate at a fraction of their former size.
Together, he says, those institutions once produced major advances in mining technology and mineral processing – the kind of industrial innovation he believes the U.S. urgently needs again.
For a startup like Kunin, Rau says, that vacuum creates opportunity.
“The timing is right because of renewed interest in mining and the growing flow of venture capital into the space,” Rau says. “I don’t think there’s been another moment when what we’re trying to do would have been this possible.”
Why Chattanooga?
Kunin did not begin in Chattanooga, but Rau says the city is a critical part of the company’s trajectory.
Rau moved to Chattanooga to work with a manufacturer experienced in producing the form factor on which Kunin’s technology relies. The move itself grew out of a venture capital connection: a West Coast investor who attended McCallie School encouraged Rau to meet the founders of Brickyard while he was in town visiting the manufacturer.
What began as a brief stop at Brickyard eventually evolved into a deeper relationship with the Chattanooga startup ecosystem and helped anchor Kunin’s early operations in the city.
“Matt and Cam were kind enough to let me work there for a day, which turned into a week and then two weeks,” Rau says, referring to Brickyard founders Matt Patterson and Cam Doody. “Eventually, they said, ‘You’re going to have to pitch us if you want to keep taking advantage of this beautiful office.’”
After Brickyard invested, Rau relocated. Kunin eventually secured industrial space on Amnicola Highway near BASF.
The company now employs seven people and is preparing for pilot deployments in Chile, the United Kingdom and the United States.
Building a team
One of the turning points for Rau came when experienced engineers and industry veterans began joining the company.
At first, Kunin was a one-man operation. Then came cofounder Corey Donovan, followed by manufacturing specialists, process engineers and senior engineering talent with decades of experience across mining, oil and gas and industrial infrastructure.
“We’ve hired two exceptional process engineers,” Rau says. “And our vice president of engineering has overseen roughly $10 billion in capital projects spanning oil and gas, polysilicon, mining and refining.”
For Rau, convincing seasoned professionals to join a startup led by a 23-year-old founder carried emotional weight beyond operational value.
“It took me a while to feel confident hiring people because I’m still quite young,” he says. “And joining a company at this stage represents a significant risk for anyone.”
The hires became validation.
“The fact that we’ve been able to bring in people with 20 or 30 years of experience from competing companies and industries speaks to the strength of the technology,” Rau says. “At this point, it’s not just a handful of sleep-deprived guys in their 20s chasing an idea. This is becoming something real.”
Scaling toward something bigger
So far, investors have committed about $2.38 million to Kunin’s growth. Rau believes the company will ultimately require vastly more capital.
“To replace conventional ion exchange resin beads at scale, Kunin will eventually need to manufacture tens of thousands of tons of its material each year,” he says. “Over the next six to eight years, we’ll likely raise around $250 million in equity and support the development of more than $5 billion in mining projects.”
Kunin plans to deploy pilot systems at mining operations over the next year as it works toward commercialization.
“Our goal is to reach the point where we can confidently say the technology is commercialized,” Rau says. “From there, the challenge becomes scaling projects and executing them successfully.”
The broader vision remains sweeping.
“We want to replace traditional ion exchange across industries, lower the cost of industrial separations and, in mining, help rebuild America’s critical mineral supply chain,” Rau says. “The vision is simple: make every mine produce every metal it can.”
The long tunnel ahead
Rau speaks about mining with something approaching reverence.
“Mining is a beautiful industry,” he says, leaning into a subject most people rarely think about unless commodity prices spike or a supply chain breaks down.
Friends and acquaintances often ask whether mining runs in Rau’s family. It does not, although he jokes that a great-grandfather once worked as a home-heating coal salesperson in the early 1900s.
Still, the obsession has spread. His brother works in commodities trading, while his sister recently began a mining-related internship while studying chemical engineering.
For Rau, the fascination comes from the scale of the challenge and the possibility that industrial technology can shape the future.
“At this point, it’s hard to separate the obsession from the excitement,” he says.
The startup grind has already taken its toll. Rau admits his mind rarely disengages from the business.
“When I go to bed, my mind immediately starts jumping ahead six months, a year, three years,” he says. “Even when I’m not actively working, I’m still thinking about the business and how to keep pushing it forward.”
Still, Rau rejects the idea that his motivation is rooted in vague aspirations about “changing the world.”
Instead, he frames the work in practical and industrial terms: humanity’s ambitions are growing, demand for metals is accelerating and someone has to solve the bottlenecks.
“If SpaceX’s Starship program succeeds, demand for metals like molybdenum and tungsten could increase tenfold or even a hundredfold over the next couple of decades,” Rau says. “And if nobody is building additional supply, prices will surge to the point that demand starts collapsing.”
The stakes, in Rau’s mind, are inseparable from the future of advanced technology itself – artificial intelligence infrastructure, electric grids, aerospace systems, semiconductors and energy production all converging around the same fundamental requirement: more metals, produced more efficiently.
That future is what keeps filling his thoughts long after midnight.
“You tell yourself there’s a light at the end of the tunnel, but if things are going well, the tunnel just keeps getting longer,” Rau says. “Eventually you stop thinking about the finish line and accept that this is simply what the work is.”