Cambridge University scientists created a solar reactor to turn plastic waste and CO2 into useful chemicals and sustainable fuels. Scientists used solar power to turn industrial and atmospheric emissions into eco-friendly liquid fuels, and plastic bottles into glycolic acid for cosmetics. The goal of the technology is to remove fossil fuels and reduce carbon from the atmosphere. With this solar power converts CO2 and plastic into sustainable fuel techniques, underground storage of carbon dioxide and its long-term consequences can be reduced.
Cambridge University scientists created a solar reactor that transforms CO2 and plastic waste into eco-friendly fuels and useful chemicals. CO2 was turned into syngas for sustainable liquid fuels and plastic bottles were turned into glycolic acid for cosmetics. In contrast to previous experiments with their solar fuel technique, the researchers used CO2 obtained from actual sources, like industrial emissions or directly from the atmosphere. Scientists captured and turned CO2 into eco-friendly fuel.
This technology still needs improvements before being used on a large scale. However, the results show an important step forward towards producing clean fuels to power the economy, without damaging the environment with oil and gas extraction.
Prof. Erwin Reisner’s team at the Yusuf Hamied Department of Chemistry has been creating renewable, carbon-neutral fuels for years, using artificial leaves and drawing inspiration from photosynthesis, the process plants use to turn sunlight into energy. By relying solely on solar power, these synthetic leaves are capable of converting water and CO2 into useful fuels.
Their solar experiments used concentrated CO2 from a cylinder, but it needs to capture CO2 from industrial processes or air for practical use. It’s hard to make technology that can convert much diluted CO2 because there are many types of molecules in the air, not just CO2.
Professor Reisner said, â€œWe’re not just interested in decarbonization, but de-fossilization – we need to completely eliminate fossil fuels in order to create a truly circular economy. In the medium term, this technology could help reduce carbon emissions by capturing them from industry and turning them into something useful, but ultimately, we need to cut fossil fuels out of the equation entirely and capture CO2 from the air.â€
The researchers drew motivation from carbon capture and storage (CCS) techniques, which entail the capture of CO2, followed by its storage underground through pumping.
In the words of Professor Reisner, â€œCCS is a technology that’s popular with the fossil fuel industry as a way to reduce carbon emissions while continuing oil and gas exploration. But if instead of carbon capture and storage, we had carbon capture and utilization, we could make something useful from CO2 instead of burying it underground, with unknown long-term consequences, and eliminate the use of fossil fuels.â€
Researchers made their solar technology work with fuel gas and air, using sunlight to turn CO2 and plastics into fuel and chemicals. The process of bubbling air through an alkaline solution allows for selective trapping of CO2 while the other gases are safely removed. By applying this bubbling technique, scientists can effectively concentrate the CO2 present in the atmosphere in a solution, thus facilitating its handling.
This integrated system contains an anode and a photocathode. One of the compartments of the system captures CO2 solution, which is then transformed into syngas, a basic type of fuel. Another one converts plastic into useful chemicals using solar energy.
Co-first author Dr. Motiar Rahaman said, â€œThe plastic component is an important trick to this system. Capturing and using CO2 from the air makes the chemistry more difficult. But, if we add plastic waste to the system, the plastic donates electrons to the CO2. The plastic breaks down to glycolic acid, which is widely used in the cosmetics industry, and the CO2 is converted into syngas, which is a simple fuel.â€
Dr. Sayan Kar, co-first author, states, “This solar-powered system takes two harmful waste products – plastic and carbon emissions – and converts them into something truly useful. The fact that we can effectively take CO2 from air and make something useful from it is special. It’s satisfying to see that we can actually do it using only sunlight.”
Dr. Rahaman added, â€œInstead of storing CO2 underground, like in CCS, we can capture it from the air and make clean fuel from it. This way, we can cut out the fossil fuel industry from the process of fuel production, which can hopefully help us avoid climate destruction.â€
Scientists are making a small and efficient device to show how using captured air with CO2 can create a zero-carbon future. Hopefully, reactors where solar power converts CO2 and plastic into sustainable fuel could help in dealing with climate change too.