The next generation of spacecraft might be powered by plants if Chinese research plays out.In a paper in the journal Joule, at team led by Yanting Liu of the Chinese Academy of Sciences in Dalian describes a new process in which cellulose – the inedible substance that makes up plant cell walls and probably the most abundant compound on Earth – is converted into rocket fuel.
Cellulose is by far the biggest component of waste plant biomass. It is, of course, useful in many applications, including the production of textiles, wood products and paper, but converting it into high intensity aviation fuel, Liu and colleagues note, brings some major added benefits.
“The catalytic conversion of renewable lignocellulose to transportation fuels is crucial to establish energy security and mitigate CO2 emissions,” they write.
The scientists’ proof-of-concept method involves converting cellulose into a toxic metabolite called 2,5-hexanedione. This is then further processed to produce a mixture of carbon molecules called polycycloalkanes – which are major components of high-end aviation fuels.
The conversion process, the researchers note, occurs under “mild conditions”, meaning that ultra-high heat or pressure in not required.
A small reconfiguration of the processing conditions, they add, tweaks the conversion so that it produces a compound called methyl cyclopentane, which can be used as an additive in high-octane petroleum.
“This new process has many advantages, such as cheaper feedstock, mild reaction conditions, fewer steps, higher density and lower freezing point of final products,” they write.
“This work provides a new strategy for the manufacture of advanced aviation fuels with cellulose.”