Building reuse into the materials around us

In a field defined by discovering, designing, and processing the materials that underpin modern technology, Diran Apelian has a resounding message: reuse can’t remain just the focus of a PhD thesis or a startup. It needs to be engineered from the beginning. 

Apelian, a metallurgist and MIT alum known for his pioneering work in molten metal processing, framed his plea with a look at society’s growing needs for materials like copper, nickel, iron, manganese—and how demand for them has surged alongside population growth over the past 150 years. 

“We’re using more and more stuff—that’s the takeaway,” said Apelian, the speaker for the MIT Department of Materials Science and Engineering (DMSE)’s Wulff Lecture on November 19. “Now, where’s all this stuff coming from? It doesn’t come from Home Depot. It comes from the Earth—planet Earth—where we take the ores out of the Earth, and we have to extract them out.” 

And more and more everyday goods depend on those ores, depleting the planet’s supplies while expending massive amounts of energy to do it, Apelian said. As one example, Apelian pointed out that computer chips, which incorporated 11 elements in 1980, now contain 52.  

Instead of simply taking, processing, and eventually discarding materials—often after passing them through inefficient recycling systems—Apelian proposes another approach: designing materials and products so that the value inside them can be recovered.  

Examples include aerospace-grade materials made from scrap aluminum alloys, optimized using AI-driven alloy blending, and shredding lithium-ion batteries to produce “black mass,” a mixture rich in cobalt, nickel, and lithium that can be refined into new cathode materials for the next generation of batteries. 

“Sustainable growth, sustainability, the development of the planet Earth is a challenge,” said Apelian—one that materials scientists and engineers are in a prime position to tackle. “It’s a profound change, but it requires material issues and challenges that are also an opportunity for us.” 

Reshaping materials design

The Wulff Lecture is no stranger to sustainability and climate issues—past speakers have discussed green iron and steel production and hydrogen-powered fuel cells. But what marked Apelian’s talk was a call for an overhaul of how materials are produced, used, and—crucially—used again. The key, he said, is “materials circularity,” which keeps Earth-derived minerals moving through the economy as long as possible, instead of being extracted, processed, used, and thrown away.  

Apelian referenced the “materials tetrahedron,” the classic framework connecting processing, structure, properties, and performance—the foundation underlying the development of most materials around us. Highlighting what’s missing, he asked DMSE students about materials at the end of their lifecycle: “You don’t really spend too much time on it, right?” 

He proposed a new framework of concentric circles that reimagines the materials lifecycle—from mining, extraction, processing, and design, to new phases focused on repair, reuse, remanufacturing, and recycling—“All the R’s,” he said. 

One pathway to more sustainable materials use, Apelian said, is tackling post-consumer waste—the everyday products people throw away once they’re done using them. 

“How can we take the waste and recover it and reuse it?” Apelian asked. 

One example is aluminum scrap processing, which has seen several advances in recent years. Traditionally, end-of-life vehicles were stripped of valuable parts fed through giant shredders; the resulting mix of metals were melted together, forfeiting much of its engineered value and “downcycled” into cast alloys used for products like engine blocks or patio furniture.  

Today, advancements in automated sensor-based sorting, machine learning and robotics, and improved melting practices mean aluminum scrap can now be directed into higher-value applications, including aerospace components and structural automotive parts—beams and supports that form a vehicle’s frame.  

“So that’s the aim, that’s the motivation: creating value out of waste,” Apelian said. 

He highlighted ongoing efforts to modernize scrap processing. He is a co-founder of Solvus Global Inc., which develops systems to convert metal scrap into high-value products, and Valis Insights, a Solvus spinout that uses sensor-based systems to identify and sort metal scraps with high precision. 

At the University of California, Irvine—where Apelian serves as distinguished professor of materials science and engineering—his group is “studying the DNA” of mixed scrap, analyzing and testing blends to prepare them for high-value applications. He has also done significant work in lithium-ion battery recycling, including co-inventing the process, commercialized by Ascend Elements, that shreds batteries and produces as a byproduct the black mass used as feedstock for new cathode materials.  

Believing in circularity 

Apelian also pointed to ways of extracting value from industrial waste: recovering metals from red mud—the highly alkaline byproduct of aluminum production—and reclaiming rare-earth elements from mine tailings. And he spotlighted the work of Shaolou Wei, a DMSE alum joining the faculty in 2026, who has developed ways to bypass the long, energy-intensive sequences traditionally used to make many alloys—reducing energy consumption and eliminating processing steps.  

Stressing that business models and policy play a critical role in enabling a circular economy, Apelian offered a scenario: “Right now, in America, when you buy a car, it’s yours. At the end of life, it’s your problem.” Owners can trade it in or sell it, but ultimately, they need to dispose of it, he said. He then mused about reversing this responsibility—requiring manufacturers to take cars back at end of life. “I’ve got to tell you, when that happens, things are going to be designed very differently.” 

Audience member Evia Rodriguez, a senior in DMSE, was struck by Apelian’s emphasis on circularity. She pointed to Patagonia—one of Apelian’s examples—as a company weaving circularity into its business model by encouraging customers to repair clothing instead of replacing it. 

“That definitely represents an optimistic idea of what could happen,” Rodriguez said. “I tend to be more skeptical, but I like to think that we could get there someday, and that we could have all companies operating on a more sustainable front.” 

First-year undergraduate Brandon Mata shared a similar outlook—balancing doubt with hope. “I think it’s easy to be pessimistic about how companies are going to act. You’re going to say people are always going to be greedy. They’re going to be selfish,” Mata said. “But regardless, I think it’s still important to have somebody like that saying, even just stating, ‘It’s important that we do this, and doing this would clearly benefit the world.’” 

Yanna Tenorio, a first-year undergrad who’s interested in the energy side of materials science, zoomed out to the overarching questions raised in the talk. “Thinking about what happens at the end of these materials’ life. How can they be reused? How can we take accountability for them?” Tenorio said. “What I find very exciting about material science in general is how much there is to be discovered.”