Nav: Home

Harnessing sunlight to pull hydrogen from wastewater

May 01, 2019

Hydrogen is a critical component in the manufacture of thousands of common products from plastic to fertilizers, but producing pure hydrogen is expensive and energy intensive. Now, a research team at Princeton University has harnessed sunlight to isolate hydrogen from industrial wastewater.

In a paper published Feb. 19 in the journal Energy & Environmental Science, the researchers reported that their process doubled the currently accepted rate for scalable technologies that produce hydrogen by splitting water.

The technique uses a specially designed chamber with a "swiss-cheese" black silicon interface to split water and isolate hydrogen gas. The process is aided by bacteria that generate electrical current when consuming organic matter in the wastewater; the current, in turn, aids the water splitting process.

The team, led by Zhiyong Jason Ren, professor of civil and environmental engineering and the Andlinger Center for Energy and the Environment, chose wastewater from breweries for the test. They ran the wastewater through the chamber, used a lamp to simulate sunlight, and watched the organic compounds breakdown and the hydrogen bubble up.

The process "allows us to treat wastewater and simultaneously generate fuels," said Jing Gu, a co-researcher and assistant professor of chemistry and biochemistry at San Diego State University.

The researchers said the technology could appeal to refineries and chemical plants, which typically produce their own hydrogen from fossil fuels, and face high costs for cleaning wastewater.

Historically, hydrogen production has relied on oil, gas or coal, and an energy-intensive method that involves processing the hydrocarbon stock with steam. Chemical manufacturers then combine the hydrogen gas with carbon or nitrogen to create high-value chemicals, such as methanol and ammonia. The two are ingredients in synthetic fibers, fertilizer, plastics and cleaning products, among other everyday goods.

Although hydrogen can be used as a vehicle fuel, the chemical industry is currently the largest producer and consumer of hydrogen. Producing chemicals in highly industrialized countries requires more energy than producing iron, steel, metals and food, according to a 2016 report from the U.S. Energy Information Administration. The report estimates that producing basic chemicals will continue to be the top industrial consumer of energy over the next two decades.

"It's a win-win situation for chemical and other industries," said Lu Lu, the first author on the study and an associate research scholar at the Andlinger Center. "They can save on wastewater treatment and save on their energy use through this hydrogen-creation process."

According to the researchers, this is the first time actual wastewater, not lab-made solutions, has been used to produce hydrogen using photocatalysis. The team produced the gas continuously over four days until the wastewater ran out, which is significant, the researchers said, because comparable systems that produce chemicals from water have historically failed after a couple hours of use. The researchers measured the hydrogen production by monitoring the amount of electrons produced by the bacteria, which directly correlates to the amount of hydrogen produced. The measurement was at the high end for similar lab experiments and, Ren said, twice as high as technologies with the potential to scale for industrial use.

Ren said he sees this technology as scalable because the chamber used to isolate the hydrogen is modular, and several can be stacked to process more wastewater and produce more hydrogen.

Though a lifecycle analysis has not yet been done, the researchers said the process will at least be energy neutral, if not energy positive, and eliminates the need for fossil fuels to create hydrogen.

The researchers said they will likely experiment with producing larger amounts of hydrogen and other gases in the future, and look forward to moving this technology to industry.
-end-


Princeton University, Engineering School

Related Hydrogen Articles:

Hydrogen energy at the root of life
A team of international researchers in Germany, France and Japan is making progress on answering the question of the origin of life.
Hydrogen alarm for remote hydrogen leak detection
Tomsk Polytechnic University jointly with the University of Chemistry and Technology of Prague proposed new sensors based on widely available optical fiber to ensure accurate detection of hydrogen molecules in the air.
Preparing for the hydrogen economy
In a world first, University of Sydney researchers have found evidence of how hydrogen causes embrittlement of steels.
Hydrogen boride nanosheets: A promising material for hydrogen carrier
Researchers at Tokyo Institute of Technology, University of Tsukuba, and colleagues in Japan report a promising hydrogen carrier in the form of hydrogen boride nanosheets.
World's fastest hydrogen sensor could pave the way for clean hydrogen energy
Hydrogen is a clean and renewable energy carrier that can power vehicles, with water as the only emission.
Chemical hydrogen storage system
Hydrogen is a highly attractive, but also highly explosive energy carrier, which requires safe, lightweight and cheap storage as well as transportation systems.
Observing hydrogen's effects in metal
Microscopy technique could help researchers design safer reactor vessels or hydrogen storage tanks.
The 'Batman' in hydrogen fuel cells
In a study published in Nature on Jan. 31, researchers at the University of Science and Technology of China (USTC) report advances in the development of hydrogen fuel cells that could increase its application in vehicles, especially in extreme temperatures like cold winters.
Paving the way for more efficient hydrogen cars
Hydrogen-powered vehicles emit only water vapor from their tailpipes, offering a cleaner alternative to fossil-fuel-based transportation.
New catalyst produces cheap hydrogen
QUT chemistry researchers have discovered cheaper and more efficient materials for producing hydrogen for the storage of renewable energy that could replace current water-splitting catalysts.
More Hydrogen News and Hydrogen Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Climate Mindset
In the past few months, human beings have come together to fight a global threat. This hour, TED speakers explore how our response can be the catalyst to fight another global crisis: climate change. Guests include political strategist Tom Rivett-Carnac, diplomat Christiana Figueres, climate justice activist Xiye Bastida, and writer, illustrator, and artist Oliver Jeffers.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Speedy Beet
There are few musical moments more well-worn than the first four notes of Beethoven's Fifth Symphony. But in this short, we find out that Beethoven might have made a last-ditch effort to keep his music from ever feeling familiar, to keep pushing his listeners to a kind of psychological limit. Big thanks to our Brooklyn Philharmonic musicians: Deborah Buck and Suzy Perelman on violin, Arash Amini on cello, and Ah Ling Neu on viola. And check out The First Four Notes, Matthew Guerrieri's book on Beethoven's Fifth. Support Radiolab today at Radiolab.org/donate.