Coincidentally a few days later a paper measured that we had already arrived on this ride; an effective strategy has been announced to convert waste from plant waste into jet fuel. Air travel today accounts for less than 5 percent of global greenhouse emissions, but its share of liftoffs is expected to grow as much as aircraft. Not only do more people fly more often, but larger sources of emissions are shrinking or are expected to begin soon. Short planes can go to high-speed rail, but for intercontinental travel, we need a way to create carbon-neutral jet fuel.
Existing alternatives like last year’s demonstration aircraft across the Pacific Ocean don’t look likely to go to a good school, but Dalian Institute of Chemical Physics Professor Ning Li has found a way to turn cellulose into jet fuel that could do better. In addition, Lee claims in the Joule Journal that the product beats petroleum-based fuels in energy density.
The polymer that gives plant cells their strength is 2,5-hexanedione through hydrogenolysis, Li first converted cellulose. After being isolated from other molecules, 2,5-hexanedione reacted with hydrogen to form a jet fuel that accomplished 10 percent more energy by mass than the materials used today. In heavier, especially long-haul aircraft, the part that will be used next will need to be burned more quickly to move.
Li said in a statement, “With this fuel, the aircraft can fly more and carry more than conventional jet fuel users, which … can reduce CO2 emissions when landing (or starting the journey) and landing.” Cellulose is exceptionally abundant. Li used wheatgrass as a source but it is the main component of wood straw and straw. It was previously converted to jet fuel, but made the multi-stage process costly. Lee hopes the more direct route will be cheaper.
Airlines can provide customers with offsets for the production of their flights, but if the acceptance rate is high enough, the world would move faster from the proper offset process to run some potential crops, such as Carinata, to produce oil that can already be produced as jet fuel. The carbon dioxide emitted during combustion balances the plants drawn from the atmosphere. However, as a small part of the mass of oil plants, this path takes up a lot of land per flight.
Another method is to make bio-jet fuel by converting plant carbohydrates into sugars and converting bacteria into ethanol. A review of the progress of Energy and Environmental Science notes that the price has dropped from a ridiculous 2007 300,000 in 2007 to one gallon. The cost of petroleum-based jet fuel a 2.50 a gallon, and the study shows that it is realistic to match it through more moderate improvements and efficiency at each stage of the process.