Wear and Friction Effects on Engine Materials of N-Butanol in Ultra-Low Sulfure Diesel Mixtures

The lack of the sulfur beneficial lubricity in ultra-low sulfur diesel (ULSD) may lead to premature wear and failure of diesel-fuel systems. Mixing of small percentages of, for instance, biodiesels and other biofuels is typically used to add lubricity in ULSD. N-butanol has been recently proved to mix in or replace diesel without compromising engine combustion performance. But anti-wear properties of mixing N-Butanol in ULSD have not previously been studied. This paper presents a tribology study on the effects of N-Butanol in ULSD in a steel-on steel sliding contact. The research work employed a pin on disk tribometer for friction-force data acquisition, and wear was measured by specimen weight-change. The wear results and the friction force evolution observed in tests indicate that the dilutions of ULSD with N-Butanol can lead to a reduction of wear and that there is an optimum rate of dilution, of around 25% of N-Butanol in ULSD, that minimizes wear and increases the mixture lubricity as compared to those of both pure ULSD and pure N-Butanol.