(CN) – Chinese scientists have developed a new plant-based biofuel that could help the aviation industry “go green,” according to research published in the journal Joule Thursday.
Researchers say the magic of this biofuel, derived from cellulose, is its high-density state that is usable as either a wholesale replacement fuel or as an additive to improve the efficiency of other jet fuels. The process converts plant waste from agriculture and timber harvesting into high-density aviation fuel and ultimately may help reduce CO2 emissions from airplanes and rockets.
“The aircraft using this fuel can fly farther and carry more than those using conventional jet fuel, which can decrease the CO2 emissions during the taking off (or launching) and landing,” study author Ni Ling of the Dalian Institute of Chemical Physics said.
To produce the biofuel, Li and his team found that cellulose – a cheap, renewable and highly abundant polymer that forms the cell walls of plants – can be selectively converted using the chemical reaction hydrogenolysis. In this study scientists used wheatgrass cellulose to obtain their final product: a mixture of C12 and C18 polycycloalkanes with a low freezing point and a density about 10 percent higher than that of conventional jet fuels.
“Our biofuel is important for mitigating CO2 emissions because it is derived from biomass and it has higher density (or volumetric heat values) compared with conventional aviation fuels,” says Li. “As we know, the utilization of high-density aviation fuel can significantly increase the range and payload of aircraft without changing the volume of oil in the tank,” Li said.
This is not the first time a biofuel made up of chain alkanes, such as branched octane, dodecane, and hexadecane, have been derived from cellulose for use in jet fuel. What is significant, however, is that researchers believe this formulation is the first to produce more complex polycycloalkane compounds that can be used as high-density aviation fuel.
Li and his team believe the process’ cheap, abundant cellulose feedstock, fewer production steps, and lower energy cost and consumption mean it will soon be ready for commercial use. They also predict it will yield higher profits than conventional aviation fuel production because it’s cheaper to produce.
The biggest roadblock to moving forward is the chemical currently used to break down the cellulose – dichloromethane. The compound has been traditionally used as a solvent in paint removers and is considered an environmental and health hazard.
“In the future, we will go on to explore the environmentally friendly and renewable organic solvent that can replace the dichloromethane used in the hydrogenolysis of cellulose to 2,5-hexanedione,” Li said. “At the same time, we will study the application of 2,5-hexanedione in the synthesis of other fuels and value-added chemicals.”