Renewable bio-jet fuel made from plants can help reduce CO2 emissions from airplanes. Scientists are looking into different ways to make this fuel, like using hydrogenated esters and fatty acids. They found that these methods could be the best for making bio-jet fuel soon. To make this fuel more competitive, researchers need to find better materials to use and figure out how to reduce emissions during production. If we can make bio-jet fuel on a large scale, it could help cut down on CO2 emissions from airplanes.