metals

Mining Metals From Water | Earth Wise

March 14, 2023 By EarthWise Leave a Comment

Researchers at the Department of Energy’s Pacific Northwest National Laboratory in Richland, Washington are working with industry to develop a method of extracting valuable materials from various sources of water. The technique is the 21st-century equivalent of panning for gold in rivers and streams.

The patent-pending technology makes use of magnetic nanoparticles that are surrounded by an absorbent shell that latches on to specific materials of interest that are found in certain water sources. These sources could include water in geothermal power plants (known as geothermal brines), water pulled from the subsurface during oil or gas production, or possibly effluents from desalination plants. Extracting valuable materials from geothermal brines could greatly enhance the economics of geothermal power plants.

The initial focus of the development is on lithium, which is an essential element in many high-technology applications, especially in the batteries that power cell phones, computers, and electric cars. The global market for lithium is projected to reach over $8 billion a year by 2028 and very little of it is currently produced in the United States.

The tiny particles are added to the water and any lithium is drawn out of the water and is bound to them. Using magnets, the nanoparticles can be readily collected. Once the particles are no longer suspended in liquid, the lithium can easily be extracted, and the nanoparticles can be reused.

PNNL is developing the technology in partnership with a company called Moselle Technology as well as with other commercial partners. This new technology offers the promise of extracting critical materials in a quick, cost-effective manner.

**********

Web Links

Tri-Cities Scientists “Magically” Mining Metals From Water

Photo, posted June 4, 2012, courtesy of Tom Shockey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Metals In Western Water Supplies | Earth Wise

October 29, 2021 By EarthWise Leave a Comment

A new study published by the University of Colorado Boulder looked at the problem of rivers being contaminated by acid rock drainage. Rocks that include sulfide-based minerals, such as pyrite, oxidize when exposed to air and water. The resulting chemical reaction produces sulfuric acid which, when present in water, dissolves metals like lead, cadmium, and zinc. The recent study found that rare earth elements are also leached out of rock by this process.

Rock drainage occurs naturally throughout the western United States, but historic mines that disturbed large amounts of rocks and soil have dramatically increased this process and have led to growing downstream water pollution. Upwards of forty percent of the headwaters of major rivers in the West are contaminated by some form of acid mine or rock drainage.

The warming climate has brought longer summers and less snow in winters. Longer, lower stream flows make it easier for metals to leach into watersheds and concentrate the metals that would otherwise be diluted by snowmelt.

Rare earth elements are essential components of many high-tech devices such as computers, hard drives, and cell phones. There is not a long history of studying the hazards they might represent when they enter the environment.

The study looked at the Snake River watershed in Colorado and found that increasing amounts of rare earth elements are entering Colorado water supplies. Concentrations of rare earth elements are not ordinarily monitored and there are no water quality standards set for them.

According to the researchers, once rare earth elements get into water, they tend to stay there. Traditional treatment processes don’t remove them. It is a growing problem that needs to be addressed.

**********

Web Links

Rare earth elements and old mines spell trouble for Western water supplies

Photo, posted October 27, 2007, courtesy of Dion Gillard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Potential Of Artificial Photosynthesis | Earth Wise

August 2, 2021 By EarthWise Leave a Comment

The sun is the primary source of energy on the earth. Enough solar energy hits the earth in one hour to meet all of human civilization’s energy needs for an entire year. The two leading forms of renewable energy – photovoltaic solar power and wind power – are ways of making use of the sun’s energy. Wind power is indirectly provided by the sun; photovoltaic power uses sunlight to generate electricity.

The most efficient use of solar energy on the planet is one perfected by plants millions of years ago: photosynthesis. Photosynthesis is a complex sequence of processes by which plants convert sunlight and water into usable energy in the form of glucose. Plants utilize a combination of pigments, proteins, enzymes, and metals to perform their magic. If we can develop artificial photosynthesis, it would be a dramatic improvement of humans’ ability to power society cleanly and efficiently. Whereas photovoltaics capture about 20% of the sun’s energy, photosynthesis stores 60% of the sun’s energy as chemical energy.

Researchers across the globe are working to develop artificial photosynthesis. A group at Purdue university has been making progress in trying to mimic the ability of leaves to collect light and split water molecules to generate hydrogen. This is a critical step in photosynthesis that is accomplished by protein and pigment complexes known as “photosystems II”. The Purdue group is experimenting with these proteins and various synthetic catalysts in order to try to develop artificial leaves based on abundant, nontoxic materials.

It is likely to take a decade or more for artificial photosynthesis technology to become part of our energy system, but its ultimate potential is enormous.

**********

Web Links

Soaking up the sun: Artificial photosynthesis promises a clean, sustainable source of energy

Photo, posted June 14, 2007, courtesy of Alex Holyoake via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Toughest Beetle Of Them All | Earth Wise

December 3, 2020 By EarthWise Leave a Comment

In 2015, UC Riverside materials scientists placed a mottled black beetle in a parking lot and ran it over with a Toyota Camry. Twice. Crushed beneath the wheels of a 3,500-pound sedan, the inch-long insect made it through without a scratch.

For the past five years, a group of scientists have been studying this remarkable bug, which has the splendid name of the diabolical ironclad beetle. Using a combination of advanced microscopy, mechanical testing, and computer simulations, the researchers have figured out the secret of this beetle’s crush resistance.

The beetle’s super-toughness lies in two armorlike structures called elytra that meet in a line, called a suture, running the length of the abdomen. The suture acts like a jigsaw puzzle. It connects various exoskeletal blades – the puzzle pieces – in the abdomen under the elytra. These structural components can act in different ways. The interconnecting blades lock to prevent themselves from pulling out of the suture. The suture and blades delaminate, leading to a graceful deformation rather than catastrophic failure. These strategies dissipate energy to circumvent fracturing.

The researchers found that the diabolical ironclad beetle – just had to say that name again – can take on an applied force of about 150 newtons, a load at least 39,000 times its body weight. (That’s the equivalent of a 150-pound person resisting the crush of about 25 blue whales).

An ongoing challenge for structural engineering is how to join together different materials without limiting their ability to support loads. The strategies evolved in these beetles may be applicable in gas turbines of aircraft, for example, where metals and composite materials are joined together with mechanical fasteners. We can learn things from the toughest beetle of them all.

**********

Web Links

Diabolical ironclad beetles inspire tougher joints for engineering applications

Photo, posted April 9, 2017, courtesy of Vahe Martirosyan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Minerals And Metals For A Low-Carbon Future | Earth Wise

February 14, 2020 By EarthWise Leave a Comment

For the past century, economies and geopolitics have largely been driven by our insatiable appetite for oil and fossil fuels in general. As we gradually make the transition to a low-carbon energy future, the focus on oil will shift to sustainable supplies of essential minerals and elements.

The use of solar panels, batteries, electric vehicle motors, wind turbines, and fuel cells is growing rapidly around the world. These technologies make use of cobalt, copper, lithium, cadmium, and various rare earth elements. The need for any one of these things may diminish if alternatives are found, but there will continue to be a growing reliance on multiple substances whose physical and chemical properties are essential to the function of modern devices and technologies.

In some cases, global supplies of particular minerals and elements are dominated by a particular country, are facing social and environmental conflicts, or face other market issues. Shortages of any of them could create economic problems and derail progress much as the oil-related energy crises of the past have.

The world faces challenges in managing the demand for low-carbon technology minerals as well as limiting the environmental and public health damage that might be associated with their extraction and processing. Expanded use of recycling and reuse of rare minerals will be essential.

As the relatively easy sources of these materials become exhausted, other resources will become more attractive. These include various valuable ecosystems, oceanic deposits, and even space-based reserves.

Ushering in the low-carbon future is not a simple matter and will require responsible actions by the world’s governments and industries. In undoing the damage from the oil age, we must avoid new damage from the low-carbon age.

**********

Web Links

Sustainable supply of minerals and metals key to a low-carbon energy future

Photo, posted March 13, 2015, courtesy of Joyce Cory via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Conspicuous Consumption

February 6, 2020 By EarthWise 2 Comments

Human civilization consumes vast amounts of material. The Circle Economy think tank actually puts some numbers on it. According to their latest report, the amount of material consumed by humanity has passed 100 billion tons every year. So, on average, every person on Earth uses more than 13 tons of materials per year.

That number has quadrupled since 1970, which is far faster than the population, which has only doubled during that time. In the past two years alone, consumption has jumped by more than 8%. While this has been going on, the proportion being recycled has been falling.

Of the 100 billion tons of materials, half of the total is sand, clay, gravel, and cement used for building, along with other minerals used for fertilizer. Coal, oil and gas make up 15% and metal ores 10%. The final quarter are plants and trees used for food and fuel. About 40% of all materials are turned into housing. A third of the annual materials consumed remain in use, such as in buildings or vehicles. But 15% is emitted into the atmosphere as greenhouse gases and a third is treated as waste.

The global emergencies of climate change and disappearing wildlife have been driven by the unsustainable extraction of fossil fuels, metals, building materials, and trees. The authors of the report warn that if we continue to treat the world’s resources as limitless, we are heading for a global disaster.

The Circle Economy think tank promotes the idea of a circular economy in which renewable energy supports systems where waste and pollution are reduced to zero. Some nations are taking steps towards circular economies, while others are not. This is a problem we can’t allow to be unaddressed.

**********