Can Nanoparticles Make Fossil Fuels Cleaner?
WHY YOU SHOULD CARE
Science is allowing us to potentially treat fossil fuels as renewable energy. It could be the ultimate game-changer in the clean energy debate.
By Joshua Eferighe
- Research in the U.S., India, Germany and Australia shows that nanoparticles can convert CO2 back into fossil fuels.
- Nanoparticles could offer a lifeline to an embattled fossil fuel industry.
It’s no secret that we’re in the midst of an environmental crisis. One scolding from 17-year-old environmental activist Greta Thunberg and you’ll be researching solar panels for your home. Carbon emissions from burning fossil fuels — coal, oil and gas — are the world’s biggest pollutants.
For the past two decades, the battle between proponents of the fossil fuel industry, the jobs it creates and those who argue that the cost to the planet and future generations is too high has been escalating. But what if there’s another way? A growing number of scientists around the world are inventing new technologies that could mitigate some of the negative effects of traditional fuels: nanoparticles that can catalyze the transformation of carbon dioxide emissions into carbon neutral fuel.
In February, the University of Southern California’s Viterbi School of Engineering announced that, in collaboration with the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL), it had discovered a metal carbide nanoparticle (a compound of carbon and metal) that can convert CO2 into fuel. Last July, scientists at India’s Tata Institute of Fundamental Research (TIFR) showed that gold nanoparticles could convert CO2 into methane. In September, researchers at Ruhr-Universität Bochum in Germany and the University of New South Wales in Australia used nanoparticles to convert CO2 into ethanol and propanol. And in October, Stanford scientists demonstrated that iron oxide nanoparticles combined with ruthenium form a catalyst that assists in breaking CO2 into fuels.
These nanoparticles — a thousand times smaller than the width of a strand of hair — have been developed sustainably at low temperatures, meaning they can be made at an industrial scale and a low cost and with minimal environmental impact.
[These technologies help scientists] develop a better understanding of how they [nanoparticles] can be tailored to converting CO2 into useful fuels or chemicals.
Frederick Baddour, National Renewable Energy Laboratory
The implications are massive. In 2017, the burning of fossil fuels was responsible for 76 percent of greenhouse gas emissions in the United States. The world pumps out nearly 40 billion tons of carbon dioxide each year. By helping convert that CO2 back into fuel rather than letting it pollute the planet, nanoparticles are promising to provide a vital pathway toward reducing the world’s greenhouse gas emissions, while allowing for the fossil fuel industry to survive without destroying the planet through the harmful environmental effects of burning coal and oil.
“What our team developed was a scalable and continuous method to prepare nanoparticles,” says Frederick Baddour, a senior scientist at NREL. They did so under conditions that allow scientists to “better control the properties of these materials and develop a better understanding of how they can be tailored to converting CO2 into useful fuels or chemicals,” he adds.
For these new technologies — as with all pathbreaking science — to prove transformative will require industrial-scale investments from big firms. And it could shift the conversation from fossil fuel firms needing to focus on clean energy and instead allow them to show their commitment to the planet by investing in mechanisms that turn fossil fuels into renewable power sources.
Not all of these discoveries have proven scalability just yet. “The amount of methane that you can produce from CO2 is not that high,” says Vivek Polshettiwar, an associate professor of chemical sciences at TIFR and co-author of the study on gold nanoparticles. That’s because the chemical reaction initiated by gold particles only happens on the surface.
That’s why USC’s Viterbi School of Engineering has come up with a system that produces more-effective nanoparticle catalysts. Using a process involving a millifluidic reactor — a small-scale chemical reactor system that has a minimal environmental footprint — smaller, more-uniform particles can be produced that are ideal for converting carbon dioxide to hydrocarbons. These nanoparticles have a higher surface area — compared to their mass — through which to work their chemistry magic.
Scientists at Stanford have devised a similar approach for producing cleaner fuel. Sophisticated X-ray characterization technologies helped researchers figure out what the perfect catalyst would be.
“There isn’t a fundamental understanding as to what catalyst is specifically needed for a good reaction,” explains Aisulu Aitbekova, a co-author of the Stanford study.
Next steps will include fine-tuning the science and finding the big investors needed to bring these technologies to market. Will ExxonMobil, Chevron and their peers in oil and gas seize the opportunity? Will progressives clamoring for an end to the fossil fuel industry see this as an opportunity for a compromise that doesn’t hurt the planet?
It’s a solution neither side has had before. Thanks to science, they do now.
- Joshua Eferighe