Biology’s growing role in the critical minerals revolution

For decades, advances in mineral processing have largely come through improvements in chemistry, equipment and process engineering. Now, a new frontier is emerging, one that borrows its inspiration from nature itself. If recent developments are any indication, biotechnology could become one of the most important innovations in the recovery of critical minerals.

The latest evidence comes from Battelle, whose researchers have announced a breakthrough in the selective separation of rare earth elements using engineered proteins. Their work demonstrates that specially designed calcium-binding proteins can distinguish between chemically similar rare earths, achieving impressive levels of purity and recovery in a single-stage, water-based process without the need for conventional chelating agents. It is an exciting development because separation, rather than extraction, remains one of the greatest technical and economic challenges in the rare earth supply chain.

The announcement also provides a timely backdrop to a keynote presentation at MEI’s Critical Minerals ’26, where Chun-Xia Zhao and colleagues from Adelaide University and the ARC Centre of Excellence for Enabling Eco-Efficient Beneficiation of Minerals will present a sustainable biotechnology platform for mineral recovery that shares the same underlying vision: using peptides and proteins as highly selective molecular tools for separating valuable minerals and metals.

The principle is remarkably elegant. Instead of relying on increasingly intensive chemical processes to force materials apart, these bioinspired molecules are engineered to recognise specific minerals and metal ions with exceptional affinity. Like a lock designed for a particular key, they selectively bind target materials, including rare earth elements and precious metals, while leaving others behind. By incorporating these peptides into recyclable protein systems, the Adelaide team has created a platform capable of repeated separation cycles without losing performance, while recombinant production offers a scalable and potentially cost-effective route to manufacturing the biomolecules themselves.

Perhaps most significant is the breadth of applications. The technology is not confined to primary mining operations; it has equal relevance to the rapidly expanding field of urban mining. End-of-life photovoltaic panels, permanent magnets and batteries represent increasingly valuable secondary resources, but their complex composition makes efficient recovery difficult. Highly selective biological separation offers the prospect of recovering critical materials from these products using water-based processes that avoid many of the harsh solvents associated with conventional techniques.

It would be premature to suggest that proteins are about to replace solvent extraction plants or flotation circuits. Laboratory success must still be translated into robust, high-throughput industrial processes capable of handling the complexity and variability of real ores and recycled feedstocks. Questions of stability, regeneration, process integration and economics will ultimately determine commercial success.

What is becoming increasingly clear, however, is that biology is moving from the margins of mineral processing research into the mainstream. Independent advances from organisations such as Battelle and Adelaide University suggest a broader shift in thinking: the future of critical minerals may depend not only on discovering new deposits, but on designing molecules capable of recognising the elements we need with extraordinary precision.

For an industry challenged to produce more critical minerals while reducing its environmental footprint, that represents a genuinely transformative opportunity and one of the most fascinating themes to watch at Critical Minerals ’26.

#CriticalMinerals26
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Memories of International Mineral Processing Congress 2006, Istanbul

In just over five weeks time the 32nd International Mineral Processing Congress will be held in Cape Town. The 23rd IMPC was held in Istanbul, Türkiye 20 years ago this month, from 3-8 September 2006. The location was particularly appropriate because Türkiye has a substantial and diverse mineral processing industry, including chromite, copper, lead-zinc, gold, borates, coal and iron. 

Bolstered by a huge Turkish contingent, the IMPC attracted over 900 delegates, then a record number (there were 751 at the last IMPC in USA). The conference included a strong body of research from Turkish universities and mining researchers, alongside international contributions and there were 453 presentations from 46 countries.

Three very memorable social events were held at the magnificent Dolmabahce and Beylerbeyi Palaces, the former being in the European sector of Istanbul, the latter across the Bosporus in Asia, and the farewell dinner was held at the end of the penultimate day of the conference, a magnificent affair rivalling the memorable ‘African Night’ at the previous Cape Town IMPC. In the splendid open air setting of Buyuk Klup, on the Asian side of the Bosporus, we were entertained, over an excellent 4-course meal, to live Turkish music, folk-dancing, and belly-dancing. There was a formal aspect to the evening as well, with final speeches from the organisers, and the lifetime achievement award to Prof. Heinrich Schubert. of the TU Bergakademie Freiberg, Germany.

Jon and I represented MEI, as a media partner, and some of our photos are shown below. There are many familiar faces, some sadly no longer with us, including the conference chairman, Prof. Güven Önal.

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From the rare earth supply challenge to processing solutions: Minerals Engineering and Critical Minerals ’26

A recent review in Minerals Engineering provides a timely assessment of one of the biggest challenges facing the critical minerals sector: how can countries develop secure rare earth elements (REE) supply chains in a world where production and processing remain heavily concentrated in China?

The review examines US domestic REE resources and projects, processing methods, emerging production capacity, non-traditional feedstocks and recycling. It also highlights the need for further R&D and, crucially, for the development of domestic expertise in REE separation and refining.

These are not simply US issues. They are at the heart of the global critical minerals challenge and they provide a timely introduction to the technical programme of Critical Minerals ’26, taking place in Cape Town in November.

As media partner to the conference, Minerals Engineering is particularly well placed to highlight the close relationship between the research published in its pages and the work that will be presented at the conference. The Minerals Engineering review makes an important point: identifying REE resources is only the beginning. The real challenge is developing economic and technically effective flowsheets to concentrate, extract, separate and refine the individual rare earth elements. Critical Minerals ’26 contains a whole session devoted to this challenge.

The programme begins with REE preconcentration and gangue rejection from monazite ore, followed by research into the beneficiation of yttrium and neodymium from an urban deposit. Later in the day, delegates will hear about reagent schemes for REE flotation and the optimisation of flotation from phosphogypsum.

These papers demonstrate the diversity of potential REE feedstocks. Traditional mined ores are being joined by industrial residues, urban deposits and waste materials, precisely the kind of non-traditional resources highlighted in the Minerals Engineering review.

And the programme goes further. Research from South Africa will examine REE extraction from coal fly ash and coal-derived ashes, while another paper investigates the influence of pH-redox conditions on recovering REEs and iron from discard-coal leach solutions.

The message is clear: future REE supply will not necessarily come from conventional mines alone. The review also highlights recycling as an important part of the emerging REE supply landscape. This is another area where the Critical Minerals ’26 programme provides a strong practical counterpart. On the second afternoon, delegates will hear about precipitation of REEs in materials recycling, recovery of REEs from spent computer hard disks using phosphoric acid and deep eutectic solvent leaching, and a life-cycle assessment of mixed REE oxide recovery from end-of-life NdFeB magnets.

These are particularly significant developments because NdFeB magnets contain some of the REEs that are strategically important to modern technologies. Recovering them from end-of-life products could provide a secondary source of supply while reducing dependence on primary mining. The conference therefore moves beyond the question of where can we find more REEs to the more fundamental question of how can we recover them efficiently from everything from ores to industrial wastes and discarded technologies?

Perhaps the most important connection with the Minerals Engineering review is the emphasis on processing expertise. The review points out that many countries have limited REE production capacity and relatively little expertise in REE processing. Developing alternative supply chains therefore requires more than investment in mines. It requires scientists, engineers, metallurgists and process developers capable of designing and operating the separation technologies needed to turn resources into saleable products.

The Critical Minerals ’26 programme reflects this need. Across its 39 presentations, researchers from universities, research organisations and industry will examine beneficiation, flotation, leaching, solvent extraction, ion exchange, precipitation, hydrometallurgy, recycling and process development across a wide range of critical minerals.

And REEs run like a thread through the programme. From monazite beneficiation and REE flotation from phosphogypsum, through coal-derived resources, acid mine drainage, recycling processes, hard-disk magnets and NdFeB magnet recycling, the papers demonstrate just how broad the search for future REE supply has become. The journal review sets out the strategic context: supply-chain concentration, the drive to establish alternative production, the development of domestic separation capacity and the need for R&D.

The conference programme shows that this research is already happening. It shows researchers tackling the difficult mineral processing questions that will determine whether new REE resources, conventional and unconventional, can actually contribute to secure supply.

And that is ultimately the purpose of Critical Minerals ’26: to look beyond the identification of critical mineral resources and focus on the processing and recycling technologies required to turn those resources into resilient supply chains. The conference explicitly covers processing from primary and secondary sources and recycling, including some of the most challenging materials associated with the circular economy. Critical Minerals ’26 offers an opportunity to see many of these emerging technologies first-hand and to meet the researchers and companies working to build the next generation of critical mineral supply chains.

The REE challenge identified in the pages of Minerals Engineering will be very much alive in Cape Town this November.

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Recovering silver from solar panels using flotation

Solar panels are one of the defining technologies of the energy transition. But as the first generations of large-scale photovoltaic installations reach the end of their useful lives, a new challenge is emerging: what do we do with millions of tonnes of spent panels?

Australia is particularly exposed to this question. Around one in three Australian households has rooftop solar, and the country is expected to generate around one million tonnes of solar panel waste by 2035. Although panels contain large quantities of glass and aluminium, they also contain smaller quantities of higher-value materials, including copper, silicon and silver.

Silver is used because it combines exceptionally high electrical conductivity allowing tiny quantities of a very valuable metal to be distributed across a huge number of microscopic conductive pathways.

Silver represents only a tiny fraction of the mass of a photovoltaic module. The Queensland Government's recent solar-panel recovery pilot, for example, estimated silver at just 0.003% of panel mass. Yet across millions of panels, even these small quantities add up. The Silver Institute reported photovoltaic demand of 193.5 million ounces of silver in 2023, highlighting just how substantial the solar industry's consumption of the metal has become.

However the silver is finely distributed, embedded within the metallisation of the cell and bonded into the surrounding material. Recovering it selectively is therefore a separation problem and that is precisely where mineral processing enters the picture. Recent research from the University of Newcastle's Centre for Critical Minerals and Urban Mining, together with the ARC Centre of Excellence, published in the July issue of Minerals Engineering, has demonstrated that froth flotation could provide a new route for recovering silver from end-of-life photovoltaic cells.

Traditional research into silver recovery from end-of-life photovoltaic modules has focused heavily on hydrometallurgical approaches, particularly acid leaching. Leaching can be effective, but treating the entire feed chemically creates its own challenges. Large quantities of reagent may be required, and much of that reagent is effectively being used to process material that contains little or no silver.

The University of Newcastle work applies froth flotation as an upstream selective recovery step for metallic silver from end-of-life photovoltaic cells. In laboratory-scale experiments, delaminated cells from waste solar panels were processed using conventional flotation reagents and the results were striking. In a rougher flotation test using tap water, the researchers achieved approximately 98% silver recovery, with a 32-fold upgrade. The flotation response was also rapid, with around 80% recovery achieved within the first minute and around 90% after approximately three minutes. Perhaps most importantly from a flowsheet perspective, flotation reduced the material requiring subsequent leaching to just 2.8% of the original feed.

The researchers' cleaner-stage experiment illustrates the potential. A rougher-cleaner configuration increased the upgrade to approximately 63, at around 87% silver recovery, producing a concentrate containing approximately 47 wt% Ag.

Of course, these are only batch laboratory results rather than evidence of a commercial-scale flowsheet. In a recent preprint they have reported impressive continuous steady state results processing the silicon wafer sourced from almost half a tonne of solar panels, bordering on 100% silver recovery with 83-fold upgrade to around 50 wt% Ag.

There is still more work to be done around feed preparation, liberation, circuit configuration, reagent optimisation, scale-up and economics. But the conceptual leap is significant. This is exactly the sort of development that demonstrates why the scope of flotation continues to expand.

MEI's Flotation '27 will bring together researchers and practitioners to discuss everything from fundamental reagent chemistry and bubble-particle interactions to flotation kinetics, hydrodynamics, scale-up, circuit design, modelling, control and environmental considerations. The solar-panel work touches on almost all of these themes.

These are not simply questions about recovering silver. They are questions about how the mineral-processing toolbox can be adapted to the emerging world of secondary resources.

The ARC Centre of Excellence is a significant University of Newcastle credential. The fact that Newcastle was awarded $35m to lead a national centre, alongside universities such as Queensland, Melbourne, Monash, New South Wales and Curtin, is strong evidence that the research group is regarded as a leading Australian centre in this area and the Newcastle group has always had a strong involvement with MEI's flotation conferences. Their involvement in the solar-recycling research is an interesting illustration of how expertise developed around conventional mineral processing problems can be transferred to entirely new resources.

The energy transition is creating a paradox. Technologies designed to reduce environmental impact require enormous quantities of materials. Those materials have to be mined, processed, manufactured and eventually recovered. The challenge is therefore not simply to build more solar panels, batteries, wind turbines and electric vehicles. It is to develop systems capable of recovering the materials contained within them when they reach the end of their useful lives. That is where mineral processing has a vitally important role.

#Flotation27

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August summary: the solar eclipse and a remarkable Cornish museum

August opened up with two more heatwaves, leading to drought conditions over most of England, including Cornwall. 

A parched Falmouth

The beaches have been packed, no more so than on the 12th of the month. August 7th-16th was  Falmouth Week, which  grew out of a sailing regatta whose roots go back to 1837. Today it's a Cornish mixture of sailing, harbour activity, live music, family events, parades and spectacular displays, bringing the town alive.

The 12th was particularly special as the Wednesday is usually dominated by an evening display by the RAF's Red Arrows, but this year there was another, more low-key evening air display and by an extraordinary coincidence the air display coincided with a 95% partial solar eclipse, the most significant solar eclipse visible from Cornwall since the total eclipse of 1999.

The aerial performances took place in the evening, from around 6pm, with the eclipsing Sun creating the backdrop as an eerie twilight descended.

Falmouth's Gyllyngvase beach at 6pm

95% totality just after 7pm

Although this was a rare occurrence I have to admit to being slightly underwhelmed. Maybe I still have in my mind exactly 27 years previously when Falmouth was on the line of totality. Although the weather was awful and the eclipsed sun was not visible I will always remember the slightly frightening sight of the black shadow racing across Falmouth Bay towards us and pitching us into total darkness as it passed.

August 11th 1999: 11am and a few minutes later

On the day after the eclipse many homes were destroyed and wildfires raged in parts of Britain as one of the highest temperatures of the year was recorded.

This summer is the hottest on record in the UK and much of Europe is on fire. The overwhelming consensus of the global scientific community is that human activity is the primary driver of current climate change (see posting of 24 August), so is 2026 the coolest year we will experience? It is an uncomfortable question, but perhaps one worth asking. The World Meteorological Organisation estimates an 86% chance that at least one year between 2026 and 2030 will be warmer than the current record year, 2024. It also puts the chance of at least one year temporarily exceeding 1.5°C above the pre-industrial average during that period at 91%. These are probabilities, not predictions that every year will be hotter than the last, since natural variations such as El Niño and La Niña will continue to cause fluctuations. But the underlying trend is clear: the baseline on which those fluctuations occur is getting warmer.

There is also a darker reminder of what a warming world can mean beyond heatwaves and wildfires. Last week, catastrophic flash floods struck Nepal after a section of glacier collapsed in the Himalayas, sending an avalanche of ice, rock and water downstream. Hundreds of people have died and thousands remain missing, with homes, roads, bridges and other infrastructure destroyed. Scientists caution that it is too early to attribute this particular event directly to climate change, but the disaster occurred in a region experiencing rapid warming and accelerating glacier loss. As glaciers retreat and high-mountain environments become increasingly unstable, the risks of landslides, avalanches and sudden floods are growing.

The Nepal disaster is a reminder that climate change is not simply a story of temperatures rising year after year. It is about a changing climate system, in which familiar patterns and natural hazards can become more dangerous. Heatwaves, wildfires, extreme rainfall, floods and the destabilisation of glaciers may look like separate events, but they are all part of a world in which the environmental baseline is shifting.

On a lighter note, last Wednesday Barbara and I celebrated our 59th wedding anniversary by visiting a remarkable museum in St. Ive (not to be confused with St. Ives), near Liskeard, 55 miles from Falmouth. The Story of Emily steps into the life and legacy of Emily Hobhouse, the famous humanitarian who was born in St. Ive, and lived from 1860 to 1926. She became internationally known for speaking out against the treatment of Boer women and children during the Second Boer War.

The British Army used a "scorched earth" policy, destroying farms and moving Boer civilians into concentration camps. Emily travelled to South Africa in 1900 to see the situation for herself. In January 1901 she visited the Bloemfontein camp, where around 2,000 women and children were being held. She was horrified by what she found. Women and children were living in terrible conditions, with inadequate food, sanitation and shelter. She documented what she saw and brought the situation to the attention of the British public and politicians. Branded an hysterical woman and traitor by many, she refused to be silenced, saving thousands of Boer women and children, leading social reforms, and single-handedly challenging an empire at war.

I remember visiting Bloemfontein in 1982. It was the capital of the old Orange Free State, one of the two Boer republics that fought Britain. The concentration camp there became one of the most important symbols of the suffering of Boer civilians and the memory was still very much alive, with some turning away as I asked for directions in English. 

Bloemfontein has the Anglo-Boer War Museum and the National Women's Memorial (left), which commemorates the women and children who died in the camps. The museum specifically tells the story of the concentration camps and the suffering of civilians, and although speaking English can cause some resentment in this predominantly Afrikaans city, ironically Emily became enormously respected among Afrikaners because she had stood up for Boer women and children and the Bloemfontein War Museum presents her positively, describing how her visit exposed the conditions in the camps and helped bring about improvements. 

She was invited to unveil the Women's Memorial in 1913, but she was too ill to attend. The wife of President Steyn unveiled it on her behalf, reading her prepared speech at the ceremony. 

Emily died in 1926. Her funeral in London was remarkably small and received little attention. A few months later, however, South Africa gave her a very different farewell.

Her ashes were sent to South Africa, where Isabella "Tibbie" Steyn, the widow of former Orange Free State president Martinus Steyn and a close friend of Hobhouse, helped organise a state funeral in Bloemfontein, the first state funeral for a woman in South Africa. It took place on 27 October 1926 at the National Women's Monument attended by more than 20,000 people. Shops and businesses closed and flags were flown at half-mast and Emily's ashes were placed at the monument.

I'm sure that South African visitors to Cornwall, and anyone interested in South African history, would find the Story of Emily of great interest. The museum is deliberately divided into two very different experiences:

• The Victorian Rectory shows Emily's childhood and early life in rural Cornwall, with restored rooms and gardens recreating the world in which she grew up.
• The War Rooms provide a modern, dark, immersive exhibition about her experiences in South Africa and the concentration camps. It uses original objects, photography, film, animation, sound and virtual reality to put visitors into the historical setting.

The contrast is intentional: the peaceful Cornish home represents Emily's early life, while the stark War Rooms represent the traumatic world she encountered later. One particularly striking feature is that the War Rooms are kept around 26°C, helping recreate the heat of South Africa. The exhibition takes visitors through different environments and uses sound, mirrors and visual effects to convey the scale and human impact of the camps.

Inside the rectory, Emily's Cornish family home

Visiting a "virtual" Boer farmhouse stoep

A devastated farmhouse during Kitchener's scorched earth policy

As well as being overshadowed by the ongoing wars in Iran and Ukraine, August will also be remembered for the loss of two iconic singer-songwriters, Bonnie Tyler and Dolly Parton, whose distinctive voices, unforgettable songs and remarkable careers left an enduring mark on popular music. Their deaths brought an end to two extraordinary chapters in music history on both sides of the Atlantic.

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Is replacing copper with aluminium the most effective way to deal with the looming global copper shortages?

A series of recent studies by reputable organisations have all forecast significant global shortages of copper starting in the mid 2030s.

In a keynote lecture at Critical Minerals '26, Martin Lynch, of the University of Queensland, will argue that substitution is the likely remedy.

Martin will highlight three main points:

• Substitutes (including PEX piping, fibre optic cables, and aluminium tubes) supplied 40% of the global demand for copper over the past 50 years, during which there were two periods of shortage.
• Of the copper consumed globally in 2023, about 70% could have been replaced by substitutes (including aluminium wiring, cables and tubes) without significant negative impacts.
• The main barrier to using substitutes is copper’s reputation for quality, and the reluctance of manufacturers and consumers to trust substitute products (including in building wire, aircon HX and renewables cabling) even though they are proven to work just as well as copper.

According to the author, history has shown that the barriers to substitution tend to crumble quite quickly when shortages appear.

Martin Lynch is the son of the late Prof. Alban Lynch, the first Director of Australia's JKMRC. He graduated in 1982 as a BE (Chem) from the University of Queensland (UQ) and worked in a series of mining companies including Rio Tinto and Iluka Resources.  During that time he wrote Mining in World History, a book which traces the history of global mining from 1500 to the 1970s (posting of 13th July 2026).  

He changed career path in 2009, becoming the owner and manager of a renewables energy business.  This was sold in 2024, following which he began a PhD at UQ focusing on the use of substitutes for copper with the aim of managing forecast global copper shortages.

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