Metals used in high-tech products face future supply risks

March 27, 2015, Yale University
Modern technology relies on virtually all of the stable elements of the periodic table. This figure, which pictures the concentrations (in parts per million) of elements on a printed circuit board, provides an illustration of that fact. The concentrations of copper and iron are obviously the highest, and others such as cesium are much lower, but concentration clearly does not reflect elemental importance: all the elements are required in order to maintain the functions for which the board was designed. Credit: Thomas Graedel, et al

In a new paper, a team of Yale researchers assesses the "criticality" of all 62 metals on the Periodic Table of Elements, providing key insights into which materials might become more difficult to find in the coming decades, which ones will exact the highest environmental costs—and which ones simply cannot be replaced as components of vital technologies.

During the past decade, sporadic shortages of metals needed to create a wide range of high-tech products have inspired attempts to quantify the criticality of these materials, defined by the relative importance of the elements' uses and their global availability.

Many of the metals traditionally used in manufacturing, such as zinc, copper, and aluminum, show no signs of vulnerability. But other metals critical in the production of newer technologies—like smartphones, infrared optics, and medical imaging—may be harder to obtain in coming decades, said Thomas Graedel, the Clifton R. Musser Professor of Industrial Ecology at the Yale School of Forestry & Environmental Studies and lead author of the paper.

The study—which was based on previous research, industry information, and expert interviews—represents the first peer-reviewed assessment of the criticality of all of the planet's metals and metalloids.

"The metals we've been using for a long time probably won't present much of a challenge. We've been using them for a long time because they're pretty abundant and they are generally widespread geographically," Graedel said. "But some metals that have become deployed for technology only in the last 10 or 20 years are available almost entirely as byproducts. You can't mine specifically for them; they often exist in small quantities and are used for specialty purposes. And they don't have any decent substitutes."

In this three-dimensional graphic, researchers illustrate the "criticality" of all 62 metals based on their scores in three areas: supply risk, environmental implications, and vulnerability to supply restrictions. Metals (some of which are indicated by their chemical symbols) with the higher levels of risk appear in the upper back right corner of the box. Credit: Thomas Graedel, et al

These findings illustrate the urgency for new product designs that make it easier to reclaim materials for re-use, Graedel said.

The paper, published in the Proceedings of the National Academy of Sciences, encapsulates the Yale group's five-year assessment of the criticality of the planet's resources in the face of rising global demand and the increasing complexity of modern products.

According to the researchers, criticality depends not only on geological abundance. Other important factors include the potential for finding effective alternatives in production processes, the degree to which ore deposits are geopolitically concentrated, the state of mining technology, regulatory oversight, geopolitical initiatives, regional instabilities, and economic policies.

In order to assess the state of all metals, researchers developed a methodology that characterizes criticality in three areas: supply risk, environmental implications, and vulnerability to human-imposed supply restrictions.

They found that supply limits for many metals critical in the emerging electronics sector (including gallium and selenium) are the result of supply risks. The environmental implications of mining and processing present the greatest challenges with platinum-group metals, gold, and mercury. For steel alloying elements (including chromium and niobium) and elements used in high-temperature alloys (tungsten and molybdenum), the greatest vulnerabilities are associated with supply restrictions.

Among the factors contributing to extreme criticality challenges are high geopolitical concentration of primary production (for example, 90 to 95% of the global supply of rare Earth metals comes from China); lack of available substitutes (there is no adequate substitute for indium, which is used in computer and cell phone displays); and political instability (a significant fraction of tantalum, used widely in electronics, comes from the war-ravaged Democratic Republic of the Congo).

The researchers also analyzed how recycling rates have evolved over the years and the degree to which different industries are able to utilize "non-virgin" sources of materials. Some materials, such as lead, are highly recycled because they are typically used in bulk, Graedel said. But the relatively rare materials that have become critical in some modern electronics are far more difficult to recycle because they are used in such miniscule amounts—and can be difficult to extricate from the increasingly complex and compact new technologies.

"I think these results should send a message to product designers to spend more time thinking about what happens after their products are no longer being used," he said. "So much of what makes the recycling of these materials difficult is their design. It seems as if it's time to think a little bit more about the end of these beautiful products."

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3 / 5 (2) Mar 27, 2015
My gosh, . . you think we may have to RECYCLE???

OH, NO!!!!

Clearly, we need to find substitutes for some of the elements which cannot be recovered, and find economical recovery processes for others.
1.7 / 5 (3) Mar 27, 2015
And exactly what are you going to replace otherwise common copper with - in wiring and other essential applications. There is no other replacement.

This article also makes laughable the mass production of nuclear reactors to solve the worlds energy problems. Problem .... there aren't enough specialty nuclear material resources available to build the reactors.
1.5 / 5 (2) Mar 28, 2015
Need to consider mining in outer space !!
1 / 5 (2) Mar 28, 2015
It's an engineering and economics issue that will be resolved, if the state does not interfere.
3 / 5 (2) Mar 28, 2015
My gosh, . . you think we may have to RECYCLE???

Recycling doesn't create new materials, it just recovers what you already have.

How are you going to recycle one solar panel into twenty more to expand production without digging up new materials?

there aren't enough specialty nuclear material resources available to build the reactors.

As proven by the Stetson-Harrison method.
3 / 5 (2) Mar 28, 2015
"How are you going to recycle one solar panel into twenty more to expand production without digging up new materials?"

Have you not seen the variety of materials we can use in PV systems? Are you aware we can build much out of Carbon fiber, and we have plenty of Carbon? Are you desperately looking for arguments?

You have continual arguments against alternative energy. What do you LIKE? Coal? Nukes?
5 / 5 (1) Mar 29, 2015
Have you not seen the variety of materials we can use in PV systems?


There is one crucial material shared by all, with no proper substitute, which is Indium, which is used in the transparent electrodes. Without transparent electrodes, you got no solar panels, so you have to figure out how to make more indium to make more solar panels.

That was the point. Recycling is not enough to supply the expansion of these technologies. They need more materials than we already have.

You have continual arguments against alternative energy. What do you LIKE? Coal? Nukes?

Stop pushing that bullshit. I have no argument against alternative energy itself as a concept.

Only against particular instances with particular problems, such as the indium shortage for solar panels. You can't ignore realities like that and pretend everything is going along swimmingly. That'd be idiotic.

5 / 5 (1) Mar 29, 2015
Are you aware we can build much out of Carbon fiber, and we have plenty of Carbon?

Carbon fiber is not made simply out of a lump of carbon. It's made out of carbonized plastic thread, typically polyacrylonitrile, which are cooked in an oven to carbonize them and the resulting carbon thread is woven into fabric.

That's right: carbon fiber is made out of fossil fuels. The epoxies that bind the carbon fiber mats into rigid parts are also made out of oil.

In your crusade for renewable energy, you don't seem to stop to think very often about what you're actually doing and what sort of technologies you're advocating for a solution to the current situation.
1 / 5 (1) Mar 29, 2015
The so-called "renewables" and "green-solution" just convert the fossil-fuel crisis into raw source crisis. As this article point outs clearly, a shift to renewable energy will just replace one non-renewable resource (fossil fuel) with another (metals and minerals). Right now wind and solar energy meet only about 1 percent of global demand; hydroelectricity meets about 7 percent. For example, to match the power generated by fossil fuels or nuclear power stations, the construction of solar energy farms and wind turbines will gobble up 15 times more concrete, 90 times more aluminum and 50 times more iron, copper and glass. Also, the wind turbines only work when there's wind, although not too much, and the solar panels only work during the day and then only when it's not cloudy.
3 / 5 (2) Mar 29, 2015
"That's right: carbon fiber is made out of fossil fuels"

Yes, Eikka, it is the correct use of fossil fuels, as feedstocks. How long will a barrel of oil last feeding a boiler? How much carbon fiber can we make from that same barrel?

And you want to turn it into pollution???

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