ASU researchers aim to pull fuels out of thin air

July 21, 2016

Nonrenewable fossil fuels give liquid fuels a bad name.

But not all liquid fuels are fossil fuels, and fuels don’t have to be dirty. The Center for Negative Carbon Emissions’ novel air-capture technology features a plastic resin that captures carbon dioxide when dry, and releases it when moist. The process has promising new applications in creating carbon-neutral liquid fuels, a greene The Center for Negative Carbon Emissions’ novel air-capture technology features a plastic resin that captures carbon dioxide when dry, and releases it when moist. The process has promising new applications in creating carbon-neutral liquid fuels, a greener alternative to fossil fuels. Photo by: Jessica Hochreiter/ASU Download Full Image

Fuels are considered dirty when they put new carbon dioxide into the atmosphere, which causes pollution and the buildup of environmentally detrimental greenhouse gases. But what if rather than using fuels that add carbon dioxide, we could create fuels that recycle carbon dioxide from the atmosphere?

Researchers at Arizona State University are exploring the idea of creating fuels that do just that: carbon-neutral liquid fuels. Think of them as fuels created out of thin air.

The endeavor builds on the advances being made at ASU’s Center for Negative Carbon Emissions, which is developing a technology that collects carbon dioxide from the atmosphere using an air-capture technique that literally scrubs it from the air and then captures it so it can be reused at an affordable cost — a carbon dioxide recycling program.

This effort moves toward closing the carbon cycle, which means making sure no new carbon dioxide ends up in the atmosphere — essential for ensuring that concentrations don’t surpass unsafe limits for life on Earth.

In addition to the environmental benefits of removing carbon dioxide, excessive amounts of it can be turned into carbon-neutral liquid fuels, making it a renewable energy source.

“The answer to our search for a sustainable future is likely to involve a combination of technologies — and fuels from air will play an important role.”

— Arvind Ramachandran, ASU environmental engineering doctoral student

How exactly can fuel be pulled from thin air? Like any magic act, it is surprisingly simple.  

First, the center's researchers generate hydrogen by using a renewable, carbon-free electricity source (such as wind energy or solar power) to split water through a process called electrolysis.

Second, this gaseous hydrogen is combined with the carbon dioxide captured from air.

What does this mixture produce? Methanol, an alcohol fuel similar to ethanol. Voila! Fuel from air.

Like ethanol, methanol can be blended with gasoline or further processed into gasoline.

“When this methanol or synthetic gasoline is burned, it releases carbon dioxide and water back into the atmosphere where it can then be recaptured and reused to make more fuel,” said Steve Atkins, a Center for Negative Carbon Emissions senior engineer who specializes in this technology.

Methanol can also be converted into plastics that would be carbon negative, or into other fuels such as diesel and jet fuel.

“If we can make air-capture affordable then we have a carbon-neutral feedstock to make liquid fuels and take advantage of abundant renewable energy,” said Christophe Jospe, who was CNCE’s chief strategist from September 2014 until June of this year and is now founding The Carbon A List to highlight the most promising approaches to capturing and recycling carbon dioxide.

The big impacts of this technology are threefold.

First, it can help society to go carbon neutral. Unlike fossil fuels, carbon-neutral liquid fuels do not add greenhouse gases or generate a net carbon footprint. Limiting, and preferably reducing, our carbon footprint is essential for sustaining life.

Second, this technology is attractive because carbon-neutral liquid fuels can be used within our current industrial infrastructure.

“If we can’t use the internal combustion engines in our cars, then we have wasted assets,” Jospe said. This renewable alternative can work within society’s current infrastructure and energy system and be more sustainable.

Third, it addresses some of the limitations of other renewable energy methods. Solar and wind power experience intermittent drops in energy production. Much like traditional liquid fuels, carbon-neutral liquid fuels can be stored long-term and used in accordance with demand.

“During periods of intermittency in renewable energy, you could utilize liquid, carbon-neutral synthetic fuels to provide electrical power,” said Atkins — though he acknowledges the round-trip efficiency (electricity to fuels and back to electricity) would be low.

lab equipment
In this mobile methanol synthesis trailer senior engineer Steve Atkins produces hydrogen and mixes it with carbon dioxide, part of the process of creating a carbon-neutral liquid fuel. Photo courtesy of Steve Atkins


Related to our transportation fleet, Jospe said, “We don’t need to move toward a totally electrified transportation fleet. We can use fuels, but the fuels need to become carbon neutral.”

Flying an airplane with an electric battery may not be a realistic option due to the reality of energy density (how much energy is contained within a unit).

“Batteries can’t pack as much electrons into the same amount of space,” Jospe said.

That means options like jet fuel are beneficial because they are lighter weight, and can power travel across further distances. Maybe it’s easiest to say that they offer users more bang for their buck.

But nonrenewable fuels, like jet fuel, also come with nasty consequences for the environment.

Promisingly, the energy density of carbon-neutral liquid fuels can be more advantageous than current batteries. They are also better than fossil fuels because they avoid adding new carbon to the atmosphere.

Arvind Ramachandran, a first-year environmental engineering doctoral student, is advancing research in converting captured carbon dioxide into fuels and chemicals under the supervision of Klaus Lackner, the director of CNCE and a professor in ASU’s Ira A. Fulton Schools of Engineering.

“I think it is very clear that we have to figure out a way to become carbon negative or at least carbon neutral,” said Ramachandran, who earned his master’s degree in chemical engineering from Columbia University.

“Making sure that our mobile sources of carbon dioxide emissions, such as cars and airplanes, are running on carbon-neutral fuels represents a powerful way of achieving carbon neutrality,” he said.

The U.S. Department of Energy’s ARPA-E REFUEL program (short for Advanced Research Projects Agency-Energy’s Renewable Energy to Fuels through Utilization of Energy-dense Liquids) is currently offering funding opportunities to encourage innovations in liquid fuel technology that promise significant impacts.

Jospe thinks the air-capture technique fits the need by supporting the synthesis of fuels made from the air. CNCE is currently applying for ARPA-E funding to advance this effort.

Getting fuels from air is not the only option researchers at ASU are exploring. Others are advancing the production of biofuels from algae as part of a multi-university project supported by a recently awarded $2 million grant from the Bioenergy Technologies Office in the U.S. Department of Energy.

Additional niche applications of the air-capture technology would make it possible to use it to carbonate beverages, create high-value chemicals and sequester carbon in products such as graphene, plastics and carbon fiber.

These and many other products and systems require the use of carbon dioxide.

“Let’s get that carbon from air so we know it’s carbon neutral, rather than a source that doesn’t help us close the carbon cycle,” Jospe said.

CNCE researchers will promote and build on these ideas further when ASU hosts the Fuels From Air Conference on Sept. 28-30. The conference will bring researchers from around the world to discuss closing the carbon cycle, techniques in taking fuels from air and different ways to turn carbon dioxide into fuels.

Ramachandran, a budding specialist in this new and exciting field, said it best: “The answer to our search for a sustainable future is likely to involve a combination of technologies — and fuels from air will play an important role.”

Rose Gochnour Serago

Communications Program Coordinator, Ira A. Fulton Schools of Engineering

image title

Addressing global water crisis with 33 Buckets

ASU group puts water filtration system into practice.
33 Buckets project could solve global water distribution problem.
July 21, 2016

World problems don’t get much bigger than the global water crisis, but innovators from Arizona State University have created a purification system and distribution model that has helped thousands of people in developing nations. The group’s work has expanded this summer, and it promises to grow.

The team — known as 33 Buckets — has traveled to Bangladesh, the Dominican Republic and Peru to install their small, customizable water filters and to train community leaders to maintain the devices and sell the clean water they produce.

Each aspect, team members say, is crucial for long-term success, removing contaminants isn’t enough.

“We have the technology to solve the clean water problem in the world,” said Swaroon Sridhar, who studies biomedical engineering and handles the group's global partnerships. “What hasn’t been addressed is an effective method of global distribution. So we changed our focus to distribution and components for filtration as well as education, which is just as important to solving the water issue.”

The efforts started in 2010 as part of the Engineering Projects in Community Service Program in ASU’s Ira A. Fulton Schools of Engineering when the team designed a bucket-based filtration system for a girls’ school in Bangladesh that would eliminate arsenic, which has the atomic number 33. The system had to be redesigned when they realized arsenic wasn’t the contamination source — but the name stuck.

In time, the group — Mark Huerta, Vid Micevic, Paul Strong and Sridhar — created a system that now helps more than 12,000 people in Bangladesh. Last summer, they launched beyond the EPICs program and started working with international nonprofits. Last month, 33 Buckets launched clean water programs in the Dominican and Peru.

“So much of that first project was spent initially learning about the issue and then designing a model that would make the best impact long-term for the community,” Strong said. “Now, we have our model and philosophy of focusing not just on design, but also on full self-sustaining, community-run projects.”

In the Dominican, members of a rural community had to walk more than a mile to fetch water from a cave. They couldn’t rely on a system of pumps and pipes because it had been poorly maintained and the groundwater source it drew from was contaminated by bacteria and coliforms, including E.coli. But now, more than 1,000 people have access to their own source of clean, affordable water using the 33 Buckets system.

In Peru, meanwhile, about 1,500 people near Cusco now get clean water from a local business that employs the 33 Buckets method. They had been depending on a water supply with bacteria levels that were 2,000 times over a limit set by the World Health Organization.

The problem of water access isn’t solved. Around the world, about 1.8 million people don’t have clean drinking water and about 8 million die of water related diseases each year. The World Economic Forum calls the global water crisis the biggest threat to the planet over the next decade.

The World Health Organization estimates that more than half of the global disease problem can be solved by clean water access and sanitation and hygiene education.

The 33 Buckets team has set out to address the problem one community at a time. Their approach allows different filters and components to be swapped in and out based on a community’s specific needs.

“The design depends on what we find, what’s locally available and what can be maintained,” Strong said.

Huerta, the group’s CEO, said the customizable system is “really good for rural areas because it’s gravity-fed, no electricity required. The maintenance is also really easy. Only a few minutes a day, and it lasts for seven to 10 years.”

Community involvement, Huerta said, is key, “especially at the early stage. If people are invested, they’re excited and realize the importance and want to dedicate their time.”

In Peru, the team relied heavily on school principal Agripino Cordova Tocrez.  

“He was so invested and confident in being able to make things work. He was a huge asset the entire time,” Huerta said. “In the Dominican Republic it was the same thing — incredible people with very interesting stories in how they came from so little and how much they value community development.”

In the Dominican, Anderson Jean and Altagracia Jean Dosil, who live near the provincial capital Monte Plata, stepped up to lead the effort.

The 33 Buckets team will stay in contact to make sure the program runs successfully. They’ll use a Google spreadsheet to see real-time water sales in Peru. And Jean and Jean Dosil will send weekly sales and maintenance reports.

In Bangladesh, meanwhile, local leaders are exploring ways to expand distribution. “We’re trying to help them finance it through water sales in the local community close to where the filter is set up,” Sridhar said.

The group also has received requests from organizations in developing nations around the world, but for now they want to focus on additional work in Peru, where they’ve established strong connections.

“Each country has its own unique circumstances, culture and connections in finding building materials and filter components, so there’s a learning curve to working in each country,” Huerta said.

He added that the group has identified two at-risk sites near Cusco, where “we plan to make assessment trips within the year and implement the projects next year.”

Monique Clement

Communications specialist , Ira A. Fulton Schools of Engineering