Bioconversion of Single-­Carbon Effluents into Biofuels and Biofuel Precursors

Biomass is a complex class of material with great potential as feedstock for the production of a wide variety of compounds, including biofuels. Its complexity, based on the variety and composition of the materials making up biomass depending on origin or source, means that a large variety of approaches must be used, ideally in an integrated manner, to fully realize this potential.

Methane and methanol are common by-products of many industrial sectors, including energy, agriculture and forestry. In fact, they are often found in waste effluents of many biomass conversion processes, be it from chemical (e.g. methanol from pulping), biological (e.g. methane from anaerobic digestion) or thermal (e.g. methane from pyrolysis) processing.

Rather than be disposed of as waste or used in marginally economically viable strategies, these single-carbon compounds (C1) can be used as low-cost feedstocks for the production of valuable bioproducts, such as biofuels and biofuel precursors, through bioconversion by methylotrophic bacteria – bacteria that can use C1 compounds as sole carbon source. This approach can be advantageous on many fronts.

- Most importantly methylotrophs convert methane and methanol to higher value products, such as designer fuel or isoprenoids for jet fuel. This, also considering that C1 compounds must often be disposed of at a cost, provides an economically viable alternative to by-product management.

- Because methylotrophic bacteria are generally robust and versatile, little or no pretreatment is required before sending C1 effluent streams for bioconversion, further improving the cost-effectiveness and economic prospects of the biofuels produced.

- Climate change creates a strong motivation to reduce industrial emissions of greenhouse gases (GHG). Methane is a common low-value industrial by-product with a global warming potential 28-36 times greater than CO2 based on a 100-year period. It is sometimes recovered for energy production or simply flared, releasing CO2. Hence, the conversion of methane effluents to valuable products can greatly reduce GHG emissions and the carbon footprint of methane-emitting processes.

- Finally, the possibility of converting methane and methanol, rather than sugars, to biofuels means there is no impact on the food chain.

The aim of this project is to develop a platform technology for the bioconversion of C1 compounds resulting from forestry activities (fermentation, thermal processing, anaerobic digestion) into biofuels (alcohols, lipids) and biofuel precursors (e.g. isoprenoids). This platform will be integrated in the greater context of biomass conversion by, for example, using by-product streams from other bioconversion activities (e.g. anaerobic digestion and pyrolysis) as feedstock.

The collaboration between the Sauvageau (Engineering) and Stein (Science) labs will create a unique setting for the development and industrialization of methylotrophic bacteria. The main areas explored will be:

  • the identification of biofuels and biofuel precursors naturally produced by methylotrophic bacteria

  • the mapping of relevant metabolic pathways

  • the implementation of advanced bioprocessing strategies to methylotrophic cultures for improved productivity

  • the development and adaptation of a methanotrophic bacteria chassis for industrial applications

  • the production of high value biofuels and biofuel precursors from methylotrophic bacteria

  • the development of efficient cell lysis and product recovery strategies

  • scale up and integration with point source industrial emitters of methane

This project will impact the energetic, economic, environmental and social aspects of biomass as a source of energy. The platform technology develop will be implementable in a variety of sectors, from energy to forestry, agriculture to waste treatment.