Why copper is the key to circularity in e-waste recycling

Over half a billion tonnes of copper have been produced since 1900, and two-thirds of it is still in productive use, according to the Fraunhofer Institute. This metal is uniquely suited to circularity, says Fernando Nuño, member of the International Copper Association and the advisory board for the electrical engineering trade show CWIEME Berlin.

Copper's unique properties make it a fundamental material in modern society, integral to various industries. Its high electrical and thermal conductivity make it indispensable in electrical wiring, electronics, and enabling the ongoing transition towards electrification.

Today, the electrical manufacturing industry faces a range of challenges, including resource scarcity and pressure to reduce its environmental impact, a significant part of which is the growing e-waste problem.

The take-make-waste model

According to the International Labour Organization, e-waste is the planet's fastest-growing waste category. But most e-waste ends up in developing countries that lack the infrastructure to treat it without harming people and the environment, and only recover a fraction of the available materials for re-use.

In 2022, 62 million tonnes of e-waste were produced, according to the UN's Global E-waste Monitor (GEM), up 82 percent compared to 2010. GEM found that the metals contained in this e-waste were worth US$91 billion, including US$19 billion of copper, US$15 billion of gold, and US$16 billion of iron.

Despite this, less than a quarter (22.3 percent) of 2022's e-waste was reported as collected and recycled, leaving billions of dollars' worth of valuable materials unaccounted for, potentially causing pollution and increasing demand for primary ores. 

Producing this much waste with a linear approach to the lives of products intensifies the scarcity of raw materials and increases the environmental impact of obtaining resources. Adopting a circular economy would close the loop, reducing reliance on virgin materials by making use of the significant quantities of materials in e-waste, and copper is among the best materials to start with.

How recyclable is copper?

In the context of a circular economy, copper's recyclability is particularly significant. It can be recycled indefinitely without any loss of performance or quality. This characteristic alone sets it apart from other metals used in electrical manufacturing.

For some other metals, recycling processes cannot handle high levels of impurities without advanced separation and refining processes, so only like-for-like recycling is possible. This means, for example, that aluminum scrap from transformer windings can only be reused to manufacture aluminum transformer windings if the waste stream is kept separate from other types of aluminum scrap.

Generally, this is not the case as it requires too much effort to create a separate recycling route for every type of aluminum. Instead, recycled metal often requires blending with virgin material to reach the required purity level, or is used in less ‘noble' applications, where purity is less important.

In addition, metals like aluminum, tin, and nickel are often alloyed to enhance their properties, but re-manufacturing pure metal from this alloyed scrap is more difficult than it is for copper. Identifying and sorting the various alloys and then recovering the constituent metals using electrolytic, pyro-, or hydrometallurgical processes is both time and energy-intensive. Often, it is too complex to keep all those waste streams separate, so the material is mainly downcycled.

Copper, on the other hand, is generally used in a highly pure form in electrical applications. In fact, around 80 per cent of copper in use is unalloyed. Even when in scrap with impurities or alloyed with other elements, recycling copper without downgrading is possible.

The refining processes for primary and secondary copper are very similar, and under the right conditions, high purity levels can be achieved from secondary material, ensuring its value and usability in high-quality applications. As a result, copper is never truly lost, and society holds a massive urban copper mine.

The circular economy starts with copper

The relatively high economic value of copper can be a driver for the recycling of other materials, too. For example, Atlantic Copper's Huelva smelter has pioneered integrating e-waste directly into its copper smelting process.

By adapting its furnaces, refining techniques, and environmental controls, the facility can efficiently recover copper and precious metals from electronic scrap, reduce energy consumption, and ensure stricter environmental compliance. Innovations in sampling, furnace design, and slag cleaning result in increased copper yield and purity, while also minimizing losses of other critical materials. 

In this way, recycling copper facilitates the recycling of other materials, such as gold, silver, nickel, tin, lead, and zinc. More than 20 different materials are being recycled in copper's slipstream. 

However, there is a limit to the percentage of demand that can be met by recycled material. Even if 100 percent of end-of-life copper is recycled, secondary copper alone cannot meet the growing demand for copper because historical demand was much lower than it is today.

For instance, the transformers and motors that reach end-of-life today are the same units that entered the market 30 years ago when sales figures were only half of what we see today, so there simply isn't enough end-of-life material available. This makes it impossible to extend the global post-consumer recycled content rate in new products above 35 to 40 percent.

Designing for circularity

Currently, around 30 percent of copper demand comes from recycled products worldwide. As mentioned above, advanced separation technology can increase that fraction, but adapting product designs to facilitate recycling is equally important.

For example, designers can make it less energy- and labour-intensive to separate the different metals present in their products, thereby improving the business case for recycling and reducing metal waste. Furthermore, communicating with smelters and recycling companies can help OEMs choose alloys most suited to recycling for their products. 

In addition, the high electrical and thermal conductivity of copper can often lead to more compact product designs, which can reduce the consumption of other materials. For example, transformers with copper windings save electrical steel compared to units with aluminum windings, while induction motors with copper rotors lead to smaller units for the same power. Trade shows like CWIEME Berlin provide excellent opportunities for collaboration along the value chain by bringing representatives from the whole electrical manufacturing industry under one roof, including metal producers, product designers, recycling companies, and OEMs. 

While its principles are rooted in age-old practices like farming, the circular economy as a structured, scalable model is a modern response to global challenges. It combines traditional wisdom with innovative tools to create a sustainable future.

How fitting it would be if the first truly circular material were copper — an element so vital to humanity's past technological advancements and now indispensable in the transition from traditional fossil fuels to more sustainable types of energy that will shape the future.

Fernando Nuño is a member of the International Copper Association and is on the advisory board for the electrical engineering trade show CWIEME Berlin.