Fueling circularity: A thorough review of circular practices in the aviation sector with sustainable fuel solutions

Aviation plays a crucial role in global economic growth and can be influenced by events like COVID-19 and climate change. The aviation sector has a significant carbon footprint that can be correlated with extreme weather conditions, outlining challenges faced by airports and proposing strategies such as environmental management, advanced fuels, and retirement of older aircraft. This review analyzes 107 scientific papers and reports to explore the opportunities to integrate a circular economy (CE) within the aviation sector, emphasizing on waste management and circular aviation practices. It highlights the sector's initiatives on in-cabin waste reduction, waste tracking systems, and plastic-free flights. Moreover, it covers the industry's efforts to adopt circular economy principles to convert waste (in-cabin and end-of-use) into Sustainable Aviation Fuels (SAFs). It outlines diverse biofuel production methods, including alcohol upgrading, fermentation, gasification-Fischer Tropsch, and thermochemical processes. It also discusses innovative technologies such as microbial and enzymatic approaches and power-to-liquid (PtL). The review examines the global challenges and policies surrounding sustainable waste management in airports, emphasizing the disconnect between sustainability goals and rising waste output accompanying the need for more effective policies and research on emissions quotas and consumption patterns. Additionally, it addresses the need for collaboration and innovative technologies regarding waste-to-energy (WtE) conversion to achieve comprehensive and efficient airport waste management strategies. The integration of CE within airport vicinities is vital to mitigate the environmental impacts by emphasizing the importance of waste management strategies and utilizing aviation waste such as cabin waste and end-of-use waste as a valuable resource for SAFs production, which continues to face several challenges related to scalability, technological readiness, and economic viability.