Page 395 - Advances in Eco-Fuels for a Sustainable Environment

Ecofuel and its compatibility with different automotive metals to assess diesel engine durability 349

observed in major portions of the metal surface. This result is expected due to the lon-
ger CCL and DU as activated ester creates a monolayer film on the metal surface. On
the contrary, higher oxygen content produced more metal oxides that enhance the
lubrication film on the sliding surface. Hence, it reduced friction and wear between
the contact surfaces for the ecofuel blend. In addition, the higher percentage of
C reinforces the greater lubricating film stability on the metal surfaces, which helps
to reduce friction and wear on the metal contact surfaces for the ecofuel blend. In all
aspects, the B20 ecofuel blend demonstrated better tribological behavior compared to
the diesel fuels.

12.4 Conclusion

It can be concluded from this study that the ecofuel blend shows less friction through-
out the test period (run-in, transitional, and steady-state conditions), indicating a rich
lubrication capability compared to that of diesel. In addition, the ecofuel demonstrated
more protected contact surface area and less mean WSD, which shows a more reliable
lubricating film that could sustain higher load and speeds without reaching the
scuffing stage. The ecofuel blend also exhibits overall better lubrication performance
by protecting the metal surface, which has been validated by analyzing the surface
morphology using SEM/EDX high-resolution microscopy. Thus, the ecofuel blend
is better in all aspects of tribological characteristics for energy saving, engine reliabil-
ity, and sustainable engine durability. A further study on the ecofuel to produce eco-
friendly and next-generation biolubricant will be desirable and is recommended.

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