Vehicles that run on diesel fuel are a major contributor to carbon emissions, which poses a challenge in the effort to reduce carbon footprint. In 2022, diesel fuel was responsible for 25% of carbon dioxide emissions from transportation in the U.S. and 10% of overall carbon dioxide emissions related to energy. To tackle this issue, Joshua Yuan from Washington University and Susie Dai from the University of Missouri have come up with an innovative solution. They have developed a method using electrocatalysis to convert carbon dioxide into electro-biodiesel, which is a much more efficient and eco-friendly alternative.
This new process is 45 times more efficient than traditional soybean-based biodiesel production and requires significantly less land. The results of their groundbreaking work have been published online in the journal Joule. Yuan and Dai’s method involves using electrocatalysis to convert carbon dioxide into biocompatible intermediates like acetate and ethanol, which are then converted into lipids or fatty acids by microbes. These lipids serve as biodiesel feedstock, making the whole process much more efficient than conventional biodiesel production.
Yuan, who is also the director of the Carbon Utilization Redesign for Biomanufacturing-Empowered Decarbonization (CURB) Engineering Research Center, explained that their electro-biodiesel process has a solar-to-molecule efficiency of 4.5%, which is significantly higher than natural photosynthesis in land plants. By using a new zinc- and copper-based catalyst and an engineered strain of the Rhodococcus jostiii bacterium, the team was able to achieve this high level of efficiency in converting carbon dioxide into lipids.
Moreover, the team conducted an analysis of the environmental impact of their process and found promising results. By using renewable resources for electrocatalysis, the electro-biodiesel process could potentially result in negative emissions, reducing 1.57 grams of carbon dioxide per gram of electro-biodiesel produced. This is a stark comparison to traditional diesel production from petroleum, which produces 0.52 grams of carbon dioxide per gram, and biodiesel production methods that produce between 2.5 to 9.9 grams of carbon dioxide per gram of lipids produced.
Yuan emphasized the significance of their research in paving the way for a more sustainable future. He stated that their process could help alleviate the biodiesel feedstock shortage and revolutionize renewable fuel, chemical, and material manufacturing. By achieving independence from fossil fuels in sectors that heavily rely on them, such as long-range heavy-duty vehicles and aircraft, the electro-biodiesel process has the potential to transform the way we approach sustainability and combat climate change.