A Green Plastic and Drop-in Transportation Fuels from Carbon Dioxide and Renewable Energy

摘要

A hydrogen-oxidizing bacterium fixed carbon dioxide (CO_2) by using clean hydrogen obtained from water electrolysis with solar power. Under nitrogen nutrient limitation, CO_2 was assimilated at 0.21 g L~(-1) h~(-1), about 7 times faster than an oil-producing green microalga. More importantly, a large portion of the reduced carbon is stored in polyhydroxybutyrate (PHB), accounting for 65% of dry cell mass. PHB is a biodegradable thermoplastic that can find a variety of environmentally friendly applications. With a solid acid catalyst, the biopolyester can be reformed into hydrocarbon oil (C6-C18) from which a gasoline-grade fuel (77 wt%) and a biodiesel-grade fuel (23 wt%) are obtained. Aromatic compounds can also be formed from PHB under acid catalysis. This paper presents an alternative route through which drop-in transportation fuels and aromatic chemicals can be directly produced from CO_2, water and renewable power.