Recent trends and advances in biogas upgrading and methanotrophs-based valorization

The global quest for sustainability in industrial activities and waste management has recently boosted biogas production worldwide. However, the rapid decrease in the levelized cost of electricity of renewable energies will soon entail electricity prices from biogas much higher than those from solar or wind power. In this context, the upgrading of biogas into biomethane represents an alternative to on-site biogas combustion. Membrane separation technology is rapidly dominating the biogas upgrading market and displacing scrubbing and adsorption technologies driven by the recent breakthroughs in material science. Similarly, biogas biorefineries have recently emerged as an innovative platform for biogas valorization capable of biotransforming methane into added value products. The limited number of bioproducts naturally synthesized by methanotrophs can be boosted via metabolic engineering of methanotrophs, while novel bioreactor configurations capable of supporting a costeffective methane mass transfer from the gas phase to the methanotrophic broth are currently under investigation to facilitate the full scale implementation of biogas biorefineries.