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An eco-friendly detergent

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Household products such as laundry detergents and dishwasher tablets are an indispensable part of everyday life, but such products contain all sorts of chemicals that have undesirable properties.  Many are difficult to break down when they enter the environment, and some add nutrients that trigger environmentally harmful algal blooms.   The ingredient lists for even what are described as environmentally friendly cleansing products can be filled with lots of polysyllabic chemicals with unknown potential impacts.  Detergents made from harmless stuff are often difficult to make, hard to rinse off, and sometimes potentially damaging to fabrics.

Researchers at Tianjin University in China have developed an environmentally friendly detergent made of tiny wood fibers and corn protein that removes stains from clothes and dishes as well as commercial products.

The researchers combined cellulose nanofibers from wood with zein protein, which is taken from corn, to produce an emulsion.  The cellulose can attract and repel water and can form emulsions and attract various kinds of stains.  The zein protein helps to stabilize the emulsion and trap oils.

They tested the new detergent by cleaning cotton cloth and dishes stained with ink, chili oil, and tomato paste.  They compared the results against commercial laundry detergent and dish soap.  Their new detergent was somewhat less effective than the commercial products when used at 1% concentration but was more effective when used at a 5% concentration. 

The results suggest that this natural detergent could be an efficient, cost-effective, and sustainable alternative to the synthetic cleaning agents that currently dominate the market.

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Researchers create eco-friendly detergent from wood fiber and corn protein

Photo, posted July 31, 2009, courtesy of Mei Anne Mendoza via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Repurposing used tires

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Every year, millions of tires from cars and trucks end up in landfills.  Just in the U.S., more than 270 million tires were scrapped in 2021 and more than 50 million of them ended up in landfills.  Discarded tires take up huge amounts of space but, more importantly, create environmental hazards.  They leach chemicals into the environment and are a serious fire hazard.

Some tires are chemically recycled via pyrolysis, which is a high-temperature process to decompose the materials in the tire.  But that process introduces harmful byproducts like benzene and dioxins. 

Researchers at the University of North Carolina Chapel Hill have introduced a new chemical method for breaking down rubber waste.  The process transforms discarded rubber into valuable precursors for epoxy resins.

Rubber – either natural rubber or the synthetic kind used in tires – is made of polymers cross-linked together to form a tough, flexible, and durable material.  These very desirable properties make it difficult to break down rubber.

The new research has led to a two-step chemical process that breaks down the rubber into functional materials that be used to produce epoxy resins.  The method does not require extremely high temperatures, uses aqueous media, and takes only six hours.   It represents an efficient, scalable solution for repurposing rubber waste which, even as many other aspects of motor vehicle are changing for the better, remains a continuing environmental problem associated with driving.

This new research marks a significant step towards greener recycling technologies.

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A Cleaner Future for Tires: Scientists Pioneer Chemical Process to Repurpose Rubber Waste

Photo, posted May 5, 2011, courtesy of TireZoo via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Removing microplastics from water

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Microplastics come from the breakdown of larger plastics in the environment as well as from direct use in various products such as certain cosmetics.  They are found everywhere, from oceans and mountain peaks to the air and water, and alarmingly, in our bodies.  They are ingested by all sorts of organisms, from tiny plankton to fish and marine mammals.  Microplastics just don’t go away.  They don’t biodegrade so they simply accumulate in the environment.

Researchers at North Carolina State University have recently demonstrated proof of concept for a system that actively removes microplastics from water.  Such a system has the potential for helping to cleanse oceans and other bodies of water from the tiny plastic particles.

The system makes use of soft dendritic colloids, which are tiny particles that have the ability to stick to just about any surface.  These sticky particles can attract microplastics and grab them, even in wet and salty conditions.  The colloids are made from chitosan, a harmless and biodegradable polymer made from processed shellfish waste.

The researchers produced small pellets of the colloids that also contain small amounts of magnesium, which makes them bubble up and rise to the surface of water.  The pellets are coated with a gelatin layer, which blocks the magnesium.  As the gelatin gradually dissolves away, the pellets collect microplastics.  Eventually, the result is a microplastic-laden scum that rises to the surface where it can be skimmed away.

The scum itself can be bioprocessed into more chitosan that can create more of these microcleaner pellets to then capture more microplastics.  The researchers are investigating how the process can be scaled up to become a valuable tool in dealing with the microplastics problem.

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New Water Microcleaners Self-Disperse, Capture Microplastics and Float Up for Removal

Photo, posted January 17, 2018, courtesy of Bo Eide via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A new way to recycle plastic

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Researchers at Northwestern University have developed a new method for recycling plastic that is safer, cleaner, cheaper, and more sustainable than those currently in use.  The U.S. is the world’s largest plastic polluter per capita, and we only recycle 5% of our plastics.  There is a pressing need for better technologies for processing different types of plastic waste.

The Northwestern method is designed to break down polyethylene terephthalate or PET, which is the most common type of polyester plastic.  PET plastic is used in food packaging and beverage bottles and represents 12% of total plastics used globally.  It does not break down easily and is therefore a major contributor to plastic pollution.  It mostly either ends up in landfills or, over time, degrades into tiny microplastics or nanoplastics that end up almost everywhere. 

The non-toxic, environmentally friendly, solvent-free Northwestern process first uses an inexpensive molybdenum catalyst to break apart the bonds in PET.  Then the broken plastic is exposed to ambient air.  Just from the trace amounts of moisture in air, the broken-down PET is converted into monomers, which are the building blocks of plastic.  The monomers could then be recycled back into PET products or used to make other valuable materials.

The process is fast and effective and takes just a few hours.  The catalyst is durable and recyclable, meaning it can be used over and over again.  It only works on polyesters, which means it can be used for recycling mixed plastics without sorting them since it will select only the PET from its inputs.

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Plastic recycling gets a breath of fresh air

Photo, posted August 10, 2013, courtesy of Lisa Risager via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Are today’s refrigerants safe?

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Refrigeration is based on heat transfer mediums that absorb heat from the area being cooled and transfer it to the outside environment.

The earliest refrigerants were dangerous substances like ammonia.  In the 1930s, chlorofluorocarbons (CFCs) like Freon became the standard refrigerant for use in refrigeration systems and even in aerosol cans.  When these substances were found to be depleting the earth’s ozone layer, the Montreal Protocol dictated their phaseout and by the mid-1990s, CFCs were largely replaced by hydrofluorocarbons (HFCs).

HFCs don’t deplete the ozone layer, but they were eventually determined to be potent greenhouse gases, thousands of times more planet-warming than carbon dioxide.   As a result, the global phaseout of HFCs began in 2016, and have been increasingly replaced by hydrofluoroolefins (HFOs), which are considered a more environmentally-friendly alternative to all their predecessors.

Trying to not be surprised by additional unpleasant discoveries about refrigerants, researchers are studying the potential environmental impacts of HFOs.  Researchers at the University of New South Wales in Australia have found that HFOs can break down in the atmosphere and that some small amounts of the resultant products are in fact fluoroforms, which are the HFC with the greatest global warming potential and can stay in the atmosphere for up to 200 years.

That only a small amount of HFC gets into the atmosphere is good, but nevertheless it reveals that the consequences of replacing widely-used chemicals are not a simple matter to determine.

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Are our refrigerants safe? The lingering questions about the chemicals keeping us cool

Photo, posted July 19, 2021, courtesy of Vernon Air Conditioning via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

PFAS and groundwater

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Per- and polyfluoroalkyl chemicals, more commonly known as PFAS, are a family of human-made chemicals that have been manufactured and used in a variety of industries since the 1940s.  They provide water-resistance, oil-resistance, dirt-resistance, and corrosion-resistance to a wide range of products, including food wrappers and packaging, clothing, dental floss, nonstick cookware, textiles, and electronics.

Exposure to PFAS has been linked to birth defects, thyroid disease, liver disease, kidney disease, and cancer.  These chemicals do not break down in the environment and therefore, over time, become concentrated in plants, animals, and people. 

According to a new first-of-its kind study by scientists at the U.S. Geological Survey, more than 20% of the U.S. population could be drinking groundwater contaminated with PFAS.  The study, which was recently published in the journal Science, found that those living in the Eastern U.S. are particularly likely to be exposed.

The study is the first to report national estimates of PFAS in untreated groundwater that supplies drinking water to private and public wells. The USGS research also provides the first estimate of the total number of Americans – anywhere from 71 to 95 million – who might be exposed to this contamination.

The researchers note that their estimates merely measure the existence of PFAS – before the water has undergone any treatment or filtering – meaning that, while they may be present, they may be at very low levels. 

To find a link to the detailed USGS map showing the probability of PFAS groundwater contamination in your region, visit our website: EarthWiseRadio.org.

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PFAS in US Groundwater Interactive Dashboard

Predictions of groundwater PFAS occurrence at drinking water supply depths in the United States

Photo, posted January 12, 2008, courtesy of Andrew Kraker via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Removing nanoplastics from water

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Plastic pollution is a growing problem for people and for the environment in multiple ways.  When plastics break down over time, they can form small particles called microplastics – bits smaller than sesame seeds – and these, in turn, can break down into even smaller pieces called nanoplastics.  They are too small to be seen with the naked eye and can enter the body’s cells and tissues.

Recent studies have shown that nanoplastics are increasingly showing up in bottled water.  In fact, measurements on several popular brands of bottled water found an average of nearly a quarter million tiny pieces of plastic in a single liter of bottled water.

The health effects of ingesting all of this plastic are not really known, but they are unlikely to be anything good.  Finding a way of avoiding this contamination of the beverages we drink is a pressing need.

Researchers at the University of Missouri have created a new liquid-based solution that eliminates more than 98% of microscopic plastic particles from water.  The method makes use of water-repelling solvents made from safe, non-toxic natural ingredients. A small amount of this designer solvent absorbs plastic particles from a large volume of water.

The solvent sits on the water’s surface.  When mixed with the water, it absorbs the plastic and eventually comes back to the surface carrying the plastic leaving behind clean, plastic -free water.

Ultimately, the hope is to scale up the process so it can be applied to increasingly large amounts of water – even lakes and, eventually, oceans.  There is work to be done, but it is a potential way to address an increasingly worrisome and pervasive form of pollution.

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Mizzou scientists achieve more than 98% efficiency removing nanoplastics from water

Photo, posted August 9, 2012, courtesy of Enid Martindale via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Forever chemicals in water

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So-called forever chemicals are pervasive in a wide range of products.  These are man-made substances called per- and polyfluoroalkyls or PFAS.  They get their unfortunate nickname because the chemical bonds in them are so strong that the compounds don’t break down for hundreds or even thousands of years.

PFAS compounds are used in makeup, dental floss, nonstick pans, food wrappers, pesticides, stain-resistant fabrics and carpets, firefighting foams, and more.  High level exposure to some of these chemicals has been linked to a variety of health problems include high cholesterol, liver and immune system damage, pregnancy problems, and kidney and testicular cancer.

A recent study published in the journal Nature Geoscience has found that PFAS chemicals are showing up in water around the world.  The study looked at more than 45,000 water samples and found that about 31% of ground water tested that wasn’t even near any obvious source of PFAS contamination had levels of the chemicals that are considered harmful to human health by the EPA.  About 16% of surface water samples – streams, rivers, ponds, and lakes – also not near any known source, had similar hazardous PFAS levels.

The EPA has now imposed strict new drinking water limits for six types of PFAS.  Going forward, water systems are required to monitor for these chemicals and remove them if they are found above allowable levels.  The new rules make the United States one of the strictest countries in the world in terms of regulating PFAS in water.

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EPA puts limits on ‘forever chemicals’ in drinking water

Photo, posted May 5, 2020, courtesy of Brandon Shaw via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Ending plastic separation anxiety

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Petroleum-based plastics are one of the biggest environmental problems we face.  They mostly end up in landfills – or worse, in the oceans and elsewhere in the environment – and they basically don’t decompose over time.  Bio-based plastics were invented to help solve the plastic waste crisis.  These materials do break down in the environment providing a potential solution to the problem.  But it turns out that they can actually make plastic waste management even more challenging.

The problem is that bioplastics look and feel so similar to conventional plastics that they get mixed in with the petroleum-based plastics rather than ending up in composters, where they can break down as designed.

Mixtures of conventional and bioplastics end up in recycling streams where they get shredded and melted down, resulting in materials that are of very poor quality for making functional products.  The only solution is to try to separate the different plastics at recycling facilities, which is difficult and expensive to do.

Scientists at Lawrence Berkeley National Laboratory, the Joint BioEnergy Institute, and the incubator company X have invented a simple “one pot” process to break down mixtures of different types of plastic using naturally derived salt solutions and specialized microbes and then produce a new type of biodegradable polymer that can be made into fresh commodity products.

The team is experimenting with various catalysts to find the optimum way to break down polymers at the lowest cost and are modeling how their processes can work at the large scales of real-world recycling facilities. Chemical recycling of plastics is a hot topic but has been difficult to make happen economically at the commercial scale.

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Putting an End to Plastic Separation Anxiety

Photo, posted November 28, 2016, courtesy of Leonard J Matthews via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Актуальная ссылка на Мега сайт обеспечивает удобный и быстрый доступ к площадке.

Tracking down PFAS toxins

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PFAS – per- and polyfluoralkyl substances – are a group of organic compounds that have been extensively used to provide water-, oil-, and dirt-resistance to a wide range of products ranging from non-stick pans, clothing, and packaging to paint, car polish, and fire-suppressant foam.  Exposure to specific PFAS compounds is associated with multiple adverse health effects, including altered immune and thyroid function, liver disease, kidney disease, poor reproductive and developmental outcomes, and cancer.  PFAS compounds do not break down in the environment and therefore, over time, become concentrated in plants, animals, and people.

Government agencies such as the EPA in this country and the EU have set strict limits for allowable levels of PFAS in drinking water.  Testing water for the trace amounts of PFAS that constitute the limits is time-consuming and expensive and requires complex equipment and experienced personnel.

Researchers at MIT have now introduced a technique for making a portable, inexpensive test that can easily and selectively detect PFAS in water samples.  The test makes use of a special polymer containing fluorinated dye molecules that cause the polymer to fluoresce red.  If PFAS are present in the sample, they enter the polymer and displace the dye molecules and switches off the red fluorescence. 

The new technique is suitable for on-site detection in highly contaminated regions.  Detecting smaller concentrations can be achieved with sufficient precision after pre-concentrating the samples using the process of solid-phase extraction.

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Tracking down Environmental Toxins

Photo, posted October 16, 2021, courtesy of Nenad Stojkovic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Lampshades And Indoor Air Pollution | Earth Wise

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We mostly think of air pollution as an outdoor problem.  Common sources of air pollution include emissions from vehicles, byproducts of manufacturing and power generation, and smoke from wildfires.  What we don’t often spend a lot of time thinking about is indoor air quality. 

Indoor air pollution refers to harmful pollutants within buildings and structures, which can lead to a myriad of health issues.  Sources of indoor air pollution include smoke from tobacco products, as well as volatile organic compounds (VOCs), including acetaldehyde and formaldehyde, emitted from things such as paints, cleaning products, plastics, and cooking. 

A team of scientists from South Korea’s Yonsei University has developed a special coating that when applied to lampshades can convert pollutants into harmless compounds.  Composed of titanium dioxide and a small amount of platinum, this thermocatalyst can be applied to the inside surface of a lampshade and is triggered to break down VOCs when warmed by the lamp’s existing incandescent or halogen bulb.

In lab tests, the coating was applied to the inside of an aluminum lampshade, warmed by a halogen bulb, and then placed into a sealed chamber containing air and acetaldehyde gas.  The researchers found that the material quickly converted the gas into acetic acid, then into formic acid, and finally into carbon dioxide and water. The scientists are now looking for ways to extend the pollutant-destroying-lampshade concept to LED lightbulbs. 

The findings offer a promising and eco-friendly solution to improve indoor air quality and reduce the health risks associated with prolonged exposure to VOCs. 

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Clever coating turns lampshades into indoor air purifiers

Photo, posted March 21, 2009, courtesy of Levent Ali via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Decontaminating Drinking Water | Earth Wise

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At least two billion people around the world often drink water that is contaminated with disease-causing microbes.  Waterborne diseases are responsible for two million deaths each year, mostly among children under the age of five.

There are various ways to decontaminate water, including chemicals that can themselves produce toxic byproducts as well as using ultraviolet light, which takes fairly long to disinfect the water and requires a source of electricity. 

Scientists at Stanford University and the SLAC National Accelerator Laboratory have recently invented a low-cost, recyclable powder that kills thousands of waterborne bacteria every second when the water containing it is exposed to ordinary sunlight.  The discovery of this ultrafast disinfectant could be a tremendous benefit to the nearly 30% of the world’s population with no reliable access to safe drinking water.

The new disinfectant is a harmless metallic powder that works by absorbing both ultraviolet and high-energy visible light from the sun.  It consists of nano-sized flakes of aluminum oxide, molybdenum sulfide, copper, and iron oxide.  The key innovation is that when these four metallic ingredients are immersed in water, they all function together by reacting with the surrounding water and generating chemicals that quickly kill bacteria. The chemicals themselves don’t last long.  They quickly break down in the water leaving completely safe drinking water.

The nontoxic powder is recyclable.  It can be removed from water with a magnet.  It can also be reused at least 30 times.  Apart from its uses in less developed parts of the world, it could be valuable for hikers and backpackers who want to drink water from natural sources of unknown quality.

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New nontoxic powder uses sunlight to quickly disinfect contaminated drinking water

Photo, posted February 27, 2013, courtesy of Petras Gagilas via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Turning Plastic Into Protein | Earth Wise

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Our planet is choking on plastic.  According to the United Nations, 79% of the 6.3 billion tons of plastic produced every year accumulates in landfills.  Half of all plastic produced is actually designed to be used just once and thrown away.  But plastic is not only accumulating on land.  In fact, the world’s oceans are projected to contain more plastic by weight than fish by the year 2050.     

According to new research, solving the plastic waste issue could help address another prominent global issue: hunger.  A multidisciplinary team of engineers, chemists, and biologists led by researchers from Michigan Tech University has developed a process to break plastics down to be recycled into useful products, including edible protein powder.

The research team’s process converts plastic into compounds using heat and a reactor that deconstructs the material’s polymer chains. The oil-like substance is then fed to a community of oil-eating bacteria.  The bacteria grow rapidly on the oily diet, producing more bacterial cells composed of roughly 55% protein.  This majority-protein byproduct is then dried out and turned into an edible powder.   The end result doesn’t look like plastic at all.  In fact, it resembles a yeast byproduct that comes from brewing beer. 

This research is funded by an award from the US Department of Defense.  The DoD often deploys soldiers in areas where access to food is challenging.  Converting plastic to protein could be part of a solution to that problem. 

While eating something that began as plastic might take some getting used to, it could be part of the solution to both plastic pollution and global hunger.

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Turning Trash Into Treasure: The Plastic to Protein Powder Solution

Beat Plastic Pollution

Photo, posted February 2, 2022, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Electricity From Bacteria | Earth Wise

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Microbiologists at Radboud University in the Netherlands have demonstrated in the laboratory that methane-consuming bacteria can generate electrical power.  Their study was recently published in the journal Frontiers in Microbiology.

The bacteria studied is called Candidatus Methanoperedens and in the natural environment it consumes methane in water sources that are contaminated with nitrogen including places like water-filled ditches and some lakes. The bacteria in the study make use of the nitrates in the water to break down and digest the methane. Methanogens, which are bacteria that reduce carbon dioxide to form methane, are the source of the methane in these places. 

The researchers exploited these complex interactions of bacteria to create a source of electrical power that is essentially a kind of battery with two terminals.  One of the terminals is a chemical terminal and one is a biological terminal.  They grew the bacteria on one of the electrodes where the bacteria donate electrons that result from its conversion of methane.  (Other microbiologists at the same institution had previously demonstrated electrical generation from a similar battery containing anammox bacteria that use ammonium rather than methane in their metabolic processing).

In the study, the Radboud scientists managed to convert 31% of the methane in the water into electricity but they are aiming at higher efficiencies. 

This approach represents a potential alternative to conventional biogas electricity generation.  In those installations, methane is produced by microorganisms digesting plant materials and the methane is subsequently burned to drive a turbine to generate power.  Those systems in fact have an efficiency of less than 50%.  The researchers want to determine whether microorganisms can do a better job of generating electricity from biological sources than combustion and turbines can do.

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Bacteria generate electricity from methane

Photo, posted December 3, 2008, courtesy of Martin Sutherland via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Pesticide From Beer | Earth Wise

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Researchers from the Neiker Basque Institute for Agricultural Research and Development in Spain have demonstrated that a combination of rapeseed cake and beer bagasse can be used to reduce populations of soil parasites and increase crop yields. 

Beer bagasse is spent brewers’ grain – the stuff that is left over after the beer is made.  Beer brewing generates substantial amounts of by-products, including large amounts of spent grain.  It already has some practical uses, including as a feedstock for biofuel, as a food additive, and it even has some medical uses.  But the new research has shown that the bagasse can be the basis for a biodisinfestation treatment to be used in agriculture.  The aim is to disinfect soils, protect soil microorganisms, and increase crop yields.

The actual material studied was a mixture of beer bagasse, rapeseed cake, and a generous amount of fresh cow manure.  The high nitrogen content of the mixture promotes the activity of beneficial microorganisms in the soil, which helps to break down organic matter and kill off nematodes and other parasites that damage crops.

Nematodes are common parasites that can penetrate plant roots to lay their eggs, which damages the root and prevents the plants from absorbing nutrients effectively.  Application of the bagasse-based mixture over 12 months increased crop yields by 15% and boosted healthy soil microbes.

The study demonstrated that agricultural byproducts can be an effective treatment for root-knot nematodes and other soil parasites, increase crop yields, and help promote sustainable food systems to reduce waste from the agricultural industry.  The researchers hope to identify other potential organic treatments for tackling soil parasite problems.

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Beer byproduct mixed with manure proves an excellent organic pesticide

Photo, posted July 1, 2011, courtesy of Quinn Dombrowski via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mollusks And Microplastics | Earth Wise

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Plastic debris comes in all different shapes and sizes, but pieces that are less than five millimeters in length are called microplastics.  Microplastics are everywhere, including in the food we eat, the water we drink, and the air we breathe.

Much of the oceanic microplastic pollution comes from the breakdown of plastic litter.  Another source of microplastic pollution is microbeads.  Microbeads, which are sometimes added to cleansing and exfoliating personal care products, pollute the environment when they get flushed down the drain.  

According to a new study by researchers at Hull York Medical School and the University of Hull in the U.K., mussels, oysters and scallops have the highest levels of microplastic contamination among seafood.  The research team examined 50 studies between 2014 and 2020 to determine the levels of microplastic contamination globally in fish and shellfish.  The team found that microplastic content was 0-10.5 microplastics per gram in mollusks, 0.1-8.6 microplastics per gram in crustaceans, and 0-2.9 microplastics per gram in fish.  

The researchers found that mollusks collected off the coasts of Asia were the most heavily contaminated with microplastics.  China, Australia, Canada, Japan and the United States are among the largest consumers of mollusks, followed by Europe and the U.K.

While the human health implications of consuming microplastics are not well understood, early evidence from other studies suggest they do cause harm. 

According to the research team, more data is needed from different parts of the world in order to better understand how microplastics vary between different oceans, seas, and waterways.

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Highest levels of microplastics found in molluscs, new study says

Photo, posted September 3, 2007, courtesy of Andrew Malone via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Generating Hydrogen From Poor-Quality Water | Earth Wise

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Hydrogen could be the basis of a complete energy system.  It could be stored and transported and could be used to power vehicles and to generate electricity in power plants.  Proponents of the so-called hydrogen economy contend that hydrogen is the best solution to the global energy challenge.  But among the challenges faced by a hydrogen economy is the development of an efficient and green method to produce hydrogen.

The primary carbon-free method of producing hydrogen is to break down water into its constituent elements – hydrogen and oxygen.  This can be done in a number of ways, notably by using electricity in a process called electrolysis.  A method that seems particularly attractive is to use sunlight as the energy source that breaks down the water molecule.

While there is an abundance of water on our planet, only some of it is suitable for people to drink and consume in other ways.    Much of the accessible water on earth is salty or polluted.  So, a technique to obtain hydrogen from water ideally should work with water that is otherwise of little use to people.

Researchers in Russia and the Czech Republic have recently developed a new material that efficiently generates hydrogen molecules by exposing water – even saltwater or polluted water – to sunlight. 

The new material is a three-layer structure composed of a thin film of gold, an ultra-thin layer of platinum, and a metal-organic framework or MOF of chromium compounds and organic molecules.  The MOF layer acts as a filter that gets rid of impurities.

Experiments have demonstrated that 100 square centimeters of the material can generate half a liter of hydrogen in an hour.  The researchers continue to improve the material and increase its efficiency over a broad range of the solar spectrum.

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New Material Can Generate Hydrogen from Salt and Polluted Water

Photo courtesy of Tomsk Polytechnic University.

Earth Wise is a production of WAMC Northeast Public Radio.

Plant-Based Bottles | Earth Wise

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Single-use plastic soda and water bottles are a real problem.  Every year, billions of them are produced – comprising nearly 300 million tons of plastic that mostly ends up in landfills or in the ocean.   This discarded plastic ends up on remote islands, in the snow atop mountains, and in trenches in the deepest parts of ocean.

There has been increasing pressure on beverage companies to put an end to this environmental disaster, but the convenience and economy of disposable bottles is just too attractive.

These bottles are made of plastic derived from oil and once they are produced, they take decades or even centuries to decompose.  Recycling them is a not-starter because it is cheaper to just make new ones.

A possible solution has emerged.  A Dutch company called Avantium has found a way to take plant sugars and transform them into a plastic capable of standing up to carbonated beverages like soda and beer but that will also break down in as little as a year in a composter or 3 years if left exposed to the elements.

Coca Cola and Carlsberg are working with Avantium to develop new drink packaging based on their material that could be in stores as soon as 2023.  The new packaging would be quite different from what we use today.  Instead of a clear or tinted bottle, beverages would come inside a cardboard container with a liner made of plant-based plastic.

It may take a while for people to get used to the change, but we have already managed to get used to milk, juice and other liquids coming in cardboard containers instead of glass or plastic bottles.  The benefits to the planet would make the effort well worthwhile.

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Plant-Based Bottles Could Degrade In One Year

Photo courtesy of Avantium.

Earth Wise is a production of WAMC Northeast Public Radio.

Harvesting Blue Energy | Earth Wise

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There are various ways to generate renewable energy from the world’s oceans, most obviously from the power of tides and waves.  But there is also an oceanic energy source called osmotic or “blue” energy.  Osmotic energy uses the differences in pressure and salinity between freshwater and saltwater to generate electricity. 

When freshwater and saltwater are mixed together, large amounts of energy are released. If the freshwater and seawater are then separated via a semi-permeable membrane, the freshwater will pass through the membrane and dilute the saltwater due to the chemical potential difference. This process is called osmosis. If the salt ions are captured completely by the membrane, the passing of water through the membrane will create a pressure known as osmotic pressure. This pressure can be used to generate electricity by using it to drive a turbine.  This has been demonstrated to work as far back as the 1970s, but the materials we have to use are not adequate to withstand ocean conditions over the long term and tend to break down quickly in the water.

New research, published in the journal Joule, looked to living organisms for inspiration to develop an improved osmotic energy system.  Scientists from the U.S. and Australia combined multiple materials to mimic the kind of high-performance membranes that are found in living organisms.  They created a hybrid membrane made from aramid microfibers (like those used in Kevlar) and boron nitride.  The new material provides both the flexibility of cartilage and the strength and stability of bone.

The researchers believe that the low cost and high stability of the new hybrid membrane will allow it to succeed in volatile marine environments.  They also expect the technology will be both efficient and scalable. 

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Inspired by the Tissues of Living Organisms, Researchers Take One Step Closer to Harvesting “Blue Energy”

Photo, posted February 14, 2017, courtesy of Marian May via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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