Third-generation biorefineries as the means to produce fuels and chemicals from CO2

Abstract

Concerns regarding petroleum depletion and global climate change caused by greenhouse gas emissions have spurred interest in renewable alternatives to fossil fuels. Third-generation (3G) biorefineries aim to utilize microbial cell factories to convert renewable energies and atmospheric CO2 into fuels and chemicals, and hence represent a route for assessing fuels and chemicals in a carbon-neutral manner. However, to establish processes competitive with the petroleum industry, it is important to clarify/evaluate/identify the most promising CO2 fixation pathways, the most appropriate CO2 utilization models and the necessary productivity levels. Here, we discuss the latest advances in 3G biorefineries. Following an overview of applications of CO2 feedstocks, mainly from flue gas and waste gasification, we review prominent opportunities and barriers in CO2 fixation and energy capture. We then summarize reported CO2-based products and industries, and describe trends and key challenges for future advancement of 3G biorefineries.

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Fig. 1: Milestones in 3G biorefineries.
Fig. 2: Key steps in 3G biorefineries.
Fig. 3: Existing CO2 fixation pathways.
Fig. 4: Theoretical CO2 fixation pathways proposed.
Fig. 5: Sketch of the different energy utilization systems for 3G biorefineries.

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Acknowledgements

This work was supported by the Beijing Advanced Innovation Center for Soft Matter Science and Engineering, National Natural Science Foundation of China (21811530003), National Key Research and Development Program (2018YFA0903000 and 2018YFA0900100), the Double First-Rate Program (ylkxj03), the Novo Nordisk Foundation (NNF10CC1016517) and the Knut and Alice Wallenberg Foundation.

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Z.L., T.T. and J.N. drafted the outline. Z.L., K.W., Y.C., T.T. and J.N. wrote the manuscript. T.T. and J.N. supervised the research. All authors have read and approved the final manuscript.

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Correspondence to Tianwei Tan or Jens Nielsen.

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Liu, Z., Wang, K., Chen, Y. et al. Third-generation biorefineries as the means to produce fuels and chemicals from CO2. Nat Catal 3, 274–288 (2020). https://doi.org/10.1038/s41929-019-0421-5

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