Transitioning away from fossil fuels is crucial to mitigate the effects of global warming and its consequences. Low-emission fuels, including liquid and gaseous biofuels (hydrogen, methane, ethanol, ammonia) play an important role in decarbonizing parts of the energy system. To expedite the shift towards a sustainable, circular economy, there is an increasing need for low carbon fuels and chemicals. The development of sustainable technology is crucial to produce low-carbon, environmentally friendly fuel that can overcome economic and technical challenges. Biogenic waste, wastewater, and biomass have emerged as promising feedstocks to produce biofuels, contributing to the development of a green economy. The production of fuels and chemicals from renewable feedstocks through fermentation process has gained considerable attention in the past two decades. Understanding the nature and composition of biogenic waste/wastewater used as feedstock and its availability is essential for determining the overall productivity and economics.

Biorefineries are crucial in transforming the energy industry by transforming renewable feedstock into low carbon fuels and chemicals. A biorefinery can potentially process range of feedstock, such as industrial and agricultural waste/residuals, to produce multitude of biobased products which include raw materials for food, feed, energy, and fertilizers.

This Topical Collection will focus on collecting articles that emphasize the principles of biorefineries and their application in the production of fuels and chemicals.

Keywords: Anaerobic digestion, Bioammonium, Biobased products, Bioelectrochemical systems, Bioeconomy, Biofuels, Biorefinery, Fermentation, Integration of processes, Low carbon fuels, Volatile fatty acids, Waste Valorization

To attain the vision of “net-zero”, bulk storage of captured CO₂ is the most feasible method, and depleted brownfield reservoirs are the most suitable sites due to their well-formed petrography, established fluid holding capacity, and injection infrastructure.

Enhanced Oil Recovery (EOR) techniques, particularly those involving CO₂, represent a crucial intersection of energy production and environmental stewardship, as they offer potential solutions to reduce greenhouse gas emissions while maximizing resource recovery from existing reservoirs. The ability to inject CO₂ into oil fields not only enhances hydrocarbon recovery but also provides a pathway for the safe sequestration of CO₂.

Topics of interest include, but are not limited to:

- Mechanisms of CO₂ in Enhanced Oil Recovery

- Saline Formation Characteristics and CO₂ Storage

- Interfacial Tension Effects on Oil Recovery

- Contact Angle Dynamics in CO₂ Flooding

- Subsurface Monitoring Techniques for EOR Applications

This Collection supports and amplifies research related to: SDG 9, and SDG 13.

Keywords: EOR, CO₂ Storage, Saline formation, IFT, Contact angle, Subsurface