A Review of Biolubricants: Approach, Challenges, Certification Aspects for Aircraft Applications

The aviation industry’s cumulative emphasis on sustainability has driven the exploration of biolubricants. Biolubricants finds a stimulating impact for the aviation industry as alternatives to traditional petroleum-derived lubricants. Ecological issues arising from the rapid depletion of petroleum reserves, health and safety risks, decarbonisation, will need to bank on low carbon kerosene drop-in alternatives which lead to researches on environmentally friendly and bio-based lubricants. The paper encompasses the effectiveness of biolubricants made from renewable sources, including vegetable oils, microbial oils; highlighting their biodegradability, low toxicity, and compatibility. Moreover, the paper comprehends the biolubricant characteristics like viscosity, thermal and oxidative stability, flash point, and pour point, etc. in comparison with conventional lubricants, and challenges in their implementation in aviation industry. Furthermore, the use of nanoparticle additives in lubricants, the modification processes for plant based oils, and the environmental benefits of biolubricants are highlighted. Barriers to the widespread use of biolubricants, including cost and availability concerns, and certification requirements, are also addressed. Finally, future research directions and opportunities for optimizing biolubricant formulations to meet the stringent performance requirements of aircraft applications while minimizing their environmental impact are discussed. Overall, biolubricants have the potential to significantly reduce the environmental impact of the aviation industry.