In a new study, researchers from the University of Cambridge explain how they have developed solar-powered technology to capture carbon dioxide and transform it into sustainable fuels.
Prior methods to capture and convert carbon dioxide existed but required energy-intensive preparation of CO2 before final capture, whereas the new method can capture directly from real-world sources, as well as being powered by cleaner solar energy.
Led by Professor Erwin Reisner, the research group has been developing sustainable net-zero carbon fuels at Cambridge for the past several years. Their experiments are inspired by leaves and produce artificial leaves which convert carbon dioxide and water into fuel using the sun — imitating the naturally occurring process of photosynthesis.
Using a solar-powered reactor, the researchers can now capture carbon dioxide released by industrial processes, as well as existing carbon dioxide from the air. They were then able to convert the CO2 into synthesis gas, or syngas. Syngas has a variety of uses and is considered a key vector for a sustainable energy future via liquid fuels.
During the same process, the system simultaneously converts used PET plastic bottles into glycolic acid.
"This solar-powered system takes two harmful waste products — plastic and carbon emissions — and converts them into something truly useful," said co-first author Dr. Sayan Kar.
The system concentrates the carbon dioxide present in the air by bubbling air through an alkaline solution, which traps the CO2 while allowing other gases to bubble out. By adding plastic waste to the system, the plastic can donate electrons to the carbon dioxide, resulting in glycolic acid from the plastic and syngas from the CO2.
The design is not yet ready to be used at an industrial scale, but it’s an important step in the move towards sustainable fuels. "The fact that we can effectively take CO2 from air and make something useful from it is special," said Kar.
"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,” Prof. Reisner said.
Sources: Joule; ScienceDirect; Science Daily