metal

Making hydrogen using bioengineering

February 28, 2025 By EarthWise Leave a Comment

Hydrogen has great potential for helping society to reach net-zero emissions. The problem is that the most economical and established production methods for hydrogen depend heavily on fossil fuels and result in roughly a dozen kilograms of carbon dioxide emissions for every kilogram of hydrogen produced.

The carbon-free way to produce hydrogen is by splitting water into its component elements. This process generally requires the use of catalysts and lots of energy.

Researchers at the University of Oxford are developing a synthetic biology approach to the production of so-called green hydrogen. The idea is to replace expensive, exotic metal-based catalysts with a highly-efficient, stable, and cost-effective catalyst based on genetically-engineered bacteria.

There are specific microorganisms that can naturally induce the chemical reaction that reduces protons to hydrogen by the use of hydrogenase enzymes. While these reactions do occur naturally, they are limited to low hydrogen yields.

The Oxford researchers genetically engineered the bacterium Shewanella oneidensis by inserting a light activated electron pump called Gloeobacter rhodopsin as well as adding nanoparticles of graphene oxide and ferric sulfate. All of this tinkering with the bacterium resulted in a ten-fold increase in hydrogen yield.

The researchers believe that their system, based entirely on biological methods rather than traditional chemical approaches, could be scaled up to produce ‘artificial leaves’ that, when exposed to sunlight, would immediately begin producing hydrogen. The Oxford work was published last summer in the Proceedings of the National Academy of Science.

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A green fuels breakthrough: bio-engineering bacteria to become ‘hydrogen nanoreactors’

Photo, posted July 27, 2016, courtesy of Blondinrikard Froberg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Native plants and road salt pollution

February 12, 2025 By EarthWise Leave a Comment

Applying salt to roadways lowers the freezing point of water and prevents slippery surfaces, which makes it safer for people to drive in wintry conditions. In the U.S., more than 22 million tons of road salt is spread every year.

But road salt harms infrastructure and the environment. In fact, road salt damages cars and metal infrastructure by accelerating rust and corrosion. Road salt can also leach into soil and waterways, disrupting ecosystems, degrading soil, contaminating water, and damaging vegetation.

In cities and towns, road salts often wash into stormwater systems, posing health concerns and challenges for infrastructure.

A new study led by researchers from Virginia Tech looked at how salt affects plants and whether certain plants could mitigate salt pollution. The research team studied stormwater detention basins in Northern Virginia, examining the impacts of road salt on plants, soils, and water quality in green infrastructure systems.

The findings, which were recently published in the journal Science of the Total Environment, found that the amount of salt present in green infrastructure systems does reach levels that threaten plant communities. However, the researchers found that relying on salt-tolerant plants for mitigation is unlikely to be effective because they simply don’t take in enough salt.

Certain plants, particularly cattails, absorbed substantial amounts of salt. But even in a basin densely planted with salt-tolerant cattails, only up to 6% of the road salt applied during winter could be removed.

Plants alone cannot solve our salt pollution problem.

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Researcher studies the power of native plants to combat road salt pollution

Photo, posted January 22, 2025, courtesy of the City of Greenville, North Carolina via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Lithium in Arkansas

November 28, 2024 By EarthWise Leave a Comment

Lithium is the critical raw material in the batteries that power electric cars as well as cell phones, computers, and other gadgets. The stuff has been nicknamed “white gold” for good reason. Chile and Australia are the world’s largest producers of the metal, which is mostly extracted from brine in evaporation ponds. The majority of it is then processed in China. The energy industry has been increasingly working to produce the raw materials needed to produce lithium-ion batteries in the United States and process those materials domestically. There are multiple projects at various stages across the country.

Researchers at the US Geological Survey and the Arkansas state government recently announced that they have discovered a vast trove of lithium in an underground brine reservoir in Arkansas.

With a combination of water testing and machine learning, the researchers determined that there could be 5 to as much as 19 million tons of lithium in the geological area called the Smackover Formation. This is more than enough to meet all the world’s demand for it.

Several companies – including Exxon Mobil, which is covering its bets on the future of oil as an energy source – are developing projects in Arkansas to produce lithium. If these companies can develop and scale up economical new ways to extract lithium from salty water, the region in Arkansas could become the lithium capital of the world.

Energy and mining companies have produced oil, gas, and other natural resources in the Smackover Formation, which extends from Texas to Florida. The same brines have long been the source of other valuable substances.

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Arkansas May Have Vast Lithium Reserves, Researchers Say

Photo, posted May 22, 2020, courtesy of the European Space Agency via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Iceland power

March 15, 2024 By EarthWise Leave a Comment

Iceland burns very little fossil fuel to power its economy and heat its homes. About 85% of its energy comes from geothermal power and hydropower. Its unique geology provides it with the highest percentage of renewable energy in the world. The fossil fuel that Iceland does burn is primarily used to power cars and trucks as well as boats in its fishing fleet. And Iceland is rapidly embracing the use of electric vehicles.

Iceland can make far more electricity than its 373,000 people can use. The majority of its electricity is essentially exported as bars of aluminum. Iceland is one of the world’s largest refiners of aluminum. The aluminum ore comes from other countries but gets shipped to Iceland where electricity is cheap. Refining aluminum is so energy-intensive that some say that aluminum is basically just pure electricity in solid metal form.

Electricity-rich Iceland is finding other ways to make use of its resources. There is a proposed project called Icelink, which is an electricity interconnector between Iceland and Great Britain. The high-voltage direct current link would run between 620 and 750 miles and would be the longest sub-sea power interconnector in the world. It is controversial in Iceland and it may or may not happen.

Another technology that is establishing an early foothold in Iceland is carbon capture. An Icelandic company called Carbix is doing leading work on taking captured carbon dioxide and sequestering it underground. Capturing and storing carbon dioxide is energy-intensive and the promise of cheap, clean geothermal power makes Iceland an attractive place to do it.

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Iceland Is Living in our Future

Photo, posted July 2, 2012, courtesy of Emily Qualey / PopTech via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Sustainable hydrogen from methane

February 14, 2024 By EarthWise Leave a Comment

Hydrogen could serve as a viable alternative to fossil fuels that can be used directly as a fuel or can be used to generate electricity to power cars and other devices. However, large-scale production of hydrogen currently relies on fossil fuels and creates carbon emissions in the process.

So-called green hydrogen involves using electricity to split water into its component elements to produce it. If the electricity is generated without emissions, then the hydrogen is truly green.

Another way to get hydrogen is by breaking down hydrocarbons like methane, which itself is a very powerful greenhouse gas. This so-called blue hydrogen could be environmentally friendly if an appropriate method for producing it can be developed.

Existing techniques for converting methane into hydrogen involve the use of metal catalysts – often nickel – that are energy-intensive to mine and manufacture, and can negatively affect the environment. Research at the University of Surrey in the UK has shown promising results for the use of nitrogen-doped nanocarbons as metal-free catalysts for the direct conversion of methane into hydrogen. One of the biggest problems with using metal catalysts for hydrogen production is that they get poisoned by carbon. The carbon that comes out of the methane ends up stopping the catalyst from continuing to do its chemical job. It turns out that the doped nanocarbon approach to hydrogen catalysis appears to be resistant to this problem.

The development of sustainable hydrogen production methods, including efficient and sustainable electrolysis of water as well as catalysis of hydrocarbons like methane, is crucial to realizing the potential of hydrogen fuel as a clean energy source.

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‘Game-changing’ findings for sustainable hydrogen production

Photo, posted April 30, 2021, courtesy of California Energy Commission via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Huge American Lithium Discovery | Earth Wise

October 12, 2023 By EarthWise Leave a Comment

Human history has often been described in terms of a succession of metal ages: the copper age, the bronze age, and the iron age. In many ways, we have now entered the lithium age. The light metal goes into the batteries that power smartphones, electric vehicles, and massive storage banks for the power grid. Lithium has become a critical strategic resource.

As it stands now, the U.S. gets most of its lithium from imports from Australia and South America. Major lithium sources are not commonplace; in 2022 there were only 45 lithium mines in the world. Many of the known deposits are not in North America but in Chile, Bolivia, Argentina, China, and Australia. The current largest known lithium deposits lie beneath the salt flats of Bolivia.

Lithium Americas Corporation, a company dedicated to advancing lithium projects to the stage of production, funded research over the past decade that has identified vast deposits of lithium-rich clay in a dormant volcanic crater along the Nevada-Oregon border. The McDermitt Caldera is estimated to hold between 20 and 40 million tons of lithium, which would make it the largest deposit in the world.

There are many questions still to answer. It is not clear how easy it will be to extract lithium from the clay, in particular how expensive or carbon-intensive it will be. There are also political complexities since the area where the lithium deposit was found is considered to be unceded ancestral land for both the Paiute and Shoshone tribes.

Apart from a dearth of domestic sources of lithium, the US also lags well behind China in lithium processing capabilities. The country has catching up to do in the new lithium age.

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America Just Hit the Lithium Jackpot

Photo, posted April 19, 2020, courtesy of Ken Lund via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Green Steel | Earth Wise

October 5, 2022 By EarthWise Leave a Comment

The Inflation Reduction Act provides $369 billion in investments to ramp up renewable energy generation and manufacturing of solar panels, wind turbines, energy storage, and electric vehicles.

Every megawatt of solar power deployed requires 35 to 45 tons of steel. Every megawatt of wind power uses 120 to 180 tons of steel. Estimates are that it will take 1.7 billion tons of steel just to build all the wind turbines needed to reach net zero emissions by 2050.

This is a big problem because steel production accounts for roughly 10% of global carbon emissions and is one of the most carbon-intensive industries in the world.

Making steel is a complex and age-old process that hasn’t changed much over time. Green steel is steel made with little or no carbon emissions. There are a few ways to do it. One is called the direct reduced iron method that uses green hydrogen instead of fossil fuel gas to produce iron and then a renewable-powered electric arc furnace to make the steel.

Molten Oxide Electrolysis is an alternative green steel approach that doesn’t depend on having a green hydrogen infrastructure. It uses electrolysis, powered by renewable energy, to separate the bonds of iron ore and produce liquid metal while releasing only oxygen in the process.

Green steel solutions rely on the availability of renewable energy, but the ultimate success of renewable energy will depend on the success of green steel. The U.S. steel industry will leverage about $6 billion under the Inflation Reduction Act to make progress on it.

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Building tomorrow’s clean energy systems on green steel

Photo, posted October 30, 2008, courtesy of Paul Bica via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastic Recycling Isn’t Working | Earth Wise

June 13, 2022 By EarthWise Leave a Comment

A recent report from several environmental organizations shows that plastic recycling rates in the U.S. have actually declined in the last several years from about 8.7% of discarded plastic to less than 6%. Meanwhile, since 1980, per capita plastic waste generation has increased 263%, totaling 218 pounds of plastic waste per person as of 2018.

Diminishing recycling rates don’t necessarily indicate a lack of interest by the public. Plastic recycling is a complicated process. There are multiple types of plastic that can’t be intermingled and there are no simple and sustainable ways to recycle many forms of plastic. On top of that, the declining recycling rate also reflects the fact that we no longer can export our plastic waste to countries like China and Turkey, which have banned U.S. waste imports.

Recycling in general is a successful practice. Paper recycling rates are around 66% as of 2020. Cardboard recycling was at 88.8% in 2020, and metal recycling rates range from 27% to 76%, depending on the type of metal. Glass recycling rates are a little over 30%. Only plastic recycling has never reached 10%, even before shipping our waste overseas and declaring it to be recycled was going on.

According to environmental organizations focused on the global plastic problem, there is no circular economy of plastics. Perhaps if truly biodegradable plastics became practical, economical, and widely utilized, the situation would be different. As things stand, the only solution is to reduce the production, use, and disposal of plastics.

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Plastics Recycling ‘Does Not Work,’ Environmentalists Stress as U.S. Recycling Rates Drop to 5%

Photo, posted May 13, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Dangers Of Thawing Permafrost | Earth Wise

April 12, 2022 By EarthWise Leave a Comment

The thawing of the permafrost in the Arctic is a major concern from the standpoint of the potential release of enormous amounts of carbon dioxide trapped in it. There are nearly 2,000 billion tons of carbon there, which is as much as humanity releases into the atmosphere in 50 years. But greenhouse gases are not the only danger posed by permafrost thawing. There are also microbes, unknown viruses, and chemicals that could be very dangerous.

More than 100 diverse microorganisms in Siberia’s deep permafrost have been found to be antibiotic resistant. The deep permafrost is one of the few environments on Earth that have not been exposed to modern antibiotics. As the permafrost thaws, its bacteria could mix with meltwater and create new antibiotic-resistant strains.

By-products of fossil fuels – introduced into permafrost environments since the beginning of the industrial revolution – are present. Metal deposits including arsenic, mercury, and nickel, have been mined for decades and have contaminated large areas.

Now-banned pollutants and chemicals – including DDT – came to the Arctic through the atmosphere and over time have become trapped in the permafrost.

There is now ongoing research further characterizing the microbes frozen in permafrost and providing more precise measurement of emissions hotspots in permafrost regions. Scientists are increasingly turning to integrated Earth observations from the ground, the air, and space.

There are models that predict the gradual release of emissions from permafrost over the next century. Other models say it could happen within just a few years. The worst-case scenario would be utterly catastrophic but none of the scenarios portend anything good.

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Thawing Permafrost Could Leach Microbes, Chemicals Into Environment

Photo, posted February 9, 2017, courtesy of Benjamin Jones/USGS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Metal From Plants | Earth Wise

March 31, 2020 By EarthWise 2 Comments

Large amounts of metal in soil are generally bad for plants. But there are about 700 species of plants that thrive in metal-rich soils. These plants don’t just tolerate minerals from soil in their bodies but actually seem to hoard them to ridiculous levels.

In areas where soils are naturally rich in nickel, typically in the tropics and Mediterranean basin, plants have either died off or have adapted to become nickel loving. Slicing open a tree with this adaptation produces a neon blue-green sap that is actually one-quarter nickel, which is far more concentrated than the ore that typically feeds commercial nickel smelters.

A group of researchers from the University of Melbourne and other institutions is investigating whether this phenomenon is not just interesting but might also be of real commercial value. They established a plot of land in a rural village in Borneo and have been harvesting growth from nickel-hyper accumulating plants. Every six to twelve months, a farmer shaves off one foot of growth from these plants and either burns or squeezes the metal out. After a short purification, they end up with about 500 pounds of nickel citrate, potentially worth thousands of dollars on international markets.

Phytomining – extracting minerals from hyper-accumulating plants – cannot fully replace traditional mining techniques. But the technology could enable areas with toxic soils to be made productive and might allow mining companies to use plants to clean up their former mines and waste while actually collecting some revenue.

There are other plants that suck up cobalt, zinc, and similarly crucial metals. With growing demand for metals, perhaps it is time to harvest them on the farm.

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Down on the Farm That Harvests Metal From Plants

Photo courtesy of the University of Queensland.

Earth Wise is a production of WAMC Northeast Public Radio.

Making Coal To Fight Climate Change

April 19, 2019 By EarthWise Leave a Comment

Coal is the most harmful fossil fuel for the environment and, furthermore, for human health. Its use has stubbornly persisted because it is so plentiful and, therefore, cheap. As a result, a big part of efforts to fight climate change is finding a way to remove the carbon dioxide dumped into the atmosphere by the combustion of coal.

Researchers at the Royal Melbourne Institute of Technology in Australia have developed a remarkable technology that in effect reverses the process that has led to soaring CO2 levels in the atmosphere. They have found a way to pull carbon dioxide from the atmosphere and turn it into coal, after which it can be stored cheaply and safely underground.

Most previous carbon capture and storage technologies have focused on compressing carbon dioxide gas into a liquid form and then pumping it into rock formations. Such techniques are rather expensive, require lots of energy, and pose risks that the liquid CO2 could escape from its underground storage sites. More recently, research on solid metal catalysts has led to the possibility of turning CO2 into solid carbon, but most of these reactions require very high temperatures and use a lot of energy.

The new technique developed at RMIT uses a new class of catalysts based on metal alloys. With a small jolt of electricity applied at room temperature, CO2 can be converted into solid carbon – basically, coal.

If this technique can be industrialized economically, it would be like turning back the clock by taking carbon dioxide that entered the atmosphere by the combustion of coal and turning it back into coal and putting it back underground. It seems like excellent environmental justice.

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Scientists Turn Atmospheric CO2 Into Coal

Photo, posted March 16, 2015, courtesy of Will Fisher via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Battery That Eats Carbon Dioxide

October 30, 2018 By EarthWise Leave a Comment

Fossil fuel-based power plants are increasingly considering the use of carbon capture technologies as a way to reduce emissions. The biggest challenge to the wide-spread adoption of such technology is its energy cost, which of course equates to economic cost. Present-day power plants equipped with carbon capture systems can use up to 30% of the electricity they generate just to power the capture, release, and storage of carbon dioxide.

Better Zinc-Air Batteries

September 26, 2017 By EarthWise Leave a Comment

Zinc-air batteries are metal-air batteries powered by oxidizing zinc with the oxygen from the air. They have high energy densities (as much as five times more energy than lithium-ion batteries) and are more environmentally friendly. Since they are based on abundant zinc, they are potentially much cheaper to produce than the lithium-ion batteries that are used in so many current applications. But because it is difficult and expensive to produce rechargeable versions of these batteries, they have only found limited use in hearing aids, in some film cameras, and in large form to power navigation instruments, oceanographic experiments and railway signals.