Co-production of fully renewable medium chain α-olefins and bio-oil hydrothermal liquefaction of biomass containing polyhydroxyalkanoic acid.

Medium chain-length linear α-olefins (-LAO) are versatile precursors to commodity products such as synthetic lubricants and biodegradable detergents, and have been traditionally produced from ethylene oligomerization and Fischer-Tropsch synthesis. Medium chain-length polyhydroxyalkanoic acid (-PHA) can be produced by some microorganisms as an energy storage. In this study, biomass that contained -PHA was used in HTL at 300 °C for 30 min, and up to 65 mol% of -PHA was converted into -LAO. The yield and quality of the bio-oil co-produced in the HTL was remarkably improved with the biomass rich in -PHA. Experiments with extracted -PHA revealed the degradation mechanism of -PHA in HTL. Overall, this work demonstrates a novel process to co-produce -LAO and bio-oil from renewable biomass.