magnets

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.

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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

Mosquito Magnets | Earth Wise

November 30, 2022 By EarthWise Leave a Comment

We’ve all probably had the experience of being in the great outdoors with other people and having some of them being nearly devoured by mosquitoes while others didn’t get bitten at all. It seemed like some people are mosquito magnets while others just aren’t the insects’ cup of tea, so to speak.

There have been various theories proposed over the years including such things as it being a question of blood type, or it having to do with how close one’s blood vessels are to their skin surface.

A new study by the Howard Hughes Medical Institute and the Rockefeller University has uncovered what appears to be the real explanation. According to the paper published in the journal Cell, certain body odors are the deciding factor. Every person has a unique scent profile associated with different chemicals present on their skin. The researchers found that people whose skin produces high levels of carboxylic acids are the most attractive to mosquitos.

The researchers collected scent samples from participants by having them wear silk stockings on their arms for six hours. The nylons were then cut into pieces and the pieces exposed to mosquitos. After several months of head-to-head battles between various nylon samples, the study clearly demonstrated that the samples from subjects with higher levels of carboxylic acids in the skin were far more attractive to mosquitos.

Humans produce the substance at much higher levels than other animals. There is little one can do about their own levels. Changing one’s diet or what soap they use doesn’t seem to make a difference.

Perhaps researchers can come up with some method of breaking down carboxylic acids in the skin in the future. Until such time, there are really people who are mosquito magnets.

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Some People Really Are Mosquito Magnets, and They’re Stuck That Way

Photo, posted September 4, 2014, courtesy of James Gathany / Centers for Disease Control via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Room-Temperature Superconductor | Earth Wise

November 18, 2020 By EarthWise Leave a Comment

One of the Holy Grails of science has apparently been found: a room-temperature superconductor. In a paper recently published in Nature, scientists from the University of Rochester and collaborators announced that they had observed superconductivity at 59 degrees Fahrenheit in an exotic material they produced in the laboratory.

Superconductivity is a phenomenon occurring in certain materials characterized by the total absence of electrical resistance. Current flowing in a closed loop of superconducting wire can go on forever. Superconductors have other unique characteristics as well, all of which combine to make them quite useful in a number of applications. Superconductors are used in high-powered magnets in particle accelerators and in MRI machines. They continue to be developed for use in electrical power transmission, energy storage, communication filters, magnetic sensors, and more.

The problem with superconductors is that they only work at very low temperatures. For most of a century – after superconductivity was discovered in 1911 – those temperatures were very close to absolute zero: 459 degrees below zero Fahrenheit. (In the late 1980s, so-called high-temperature superconductors were discovered. Those materials superconduct at the temperature of liquid nitrogen: about 320 degrees below zero).

The dream has been to find a superconductor that works at ambient temperatures. The Rochester team has produced tiny amounts of a mysterious combination of hydrogen, carbon, and sulfur which, when subjected to extraordinarily high pressures (over 2 million atmospheres), superconducts at the temperature of a pleasant fall day.

There is no practical value for this first room-temperature superconductor, but it proves that superconductivity can exist at ambient temperature. Once something is shown to exist at all, there is reason to hope that it can occur in ways that are easier and more practical to attain.

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First room-temperature superconductor excites — and baffles — scientists

Photo, posted June 18, 2013, courtesy of Oak Ridge National Laboratory via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rare Earths From Mining Waste

May 3, 2019 By EarthWise Leave a Comment

The 17 rare earth elements have become important parts of much of modern technology. Despite their name, most of these elements are relatively plentiful in the earth’s crust, but because of their geochemical properties they are typically dispersed and not often found concentrated in minerals. As a result, economically exploitable ore deposits are uncommon. There are no significant sources in the U.S.

Rare earths play important roles in high-performance magnets, electric motors in vehicles, wind turbines, microphones and speakers, and in portable electronics like cell phones. As these applications become ever larger, the need for additional sources of rare earths increases.

Researchers at Idaho National Laboratory and Rutgers University have studied a method for extracting rare-earth elements from mining waste that could greatly increase the world’s supply of these valuable materials.

It turns out that large amounts of rare earths exist in phosphogypsum, a waste product from producing phosphoric acid from phosphate rock. The U.S. alone mined 28 million tons of phosphate rock in 2017. (Phosphoric acid is used in the production of fertilizers and other products).

The researchers estimate that more than a billion tons of phosphogypsum waste sits in piles at storage sites across the U.S. alone. World-wide, about 100,000 tons of rare earth elements per year end up in phosphogypsum waste. This compares to the total current world-wide production of rare earth oxides of 126,000 tons.

The researchers studied methods for extracting the elements from the waste. A method utilizing a common environmental bacterium showed great promise.

There are concerns about residual radioactivity and other environmental issues in dealing with the waste material, but the world’s supply of rare earth elements might become much greater based on this research.

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Critical Materials: Researchers Eye Huge Supply of Rare-Earth Elements from Mining Waste

Photo, posted June 19, 2015, courtesy of David Stanley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.