Determination of the Influence of Potential Future Bio Diesel Components on Fuel Stability in a Diesel Hybrid Engine

Authors

Dr. M. Frauscher, Dr. A. Ristic, A. Agocs BSc, AC2T research GmbH, Wiener Neustadt; Dr. L. Nenning, Graz University of Technology; Dipl.-Ing. M. Miedler, Dipl.-Ing. T. Uitz, OMV Downstream GmbH, Vienna:

Year

2023

Print Info

Production/Publication ÖVK

Summary

In this study a self-developed Diesel hybrid test rig was used to simulate the fuel circulation and ageing.

Based on a tailor-made, close to real life stress-circle, various fuel blends, differing in components, additives and bio content, were applied in the test rig over a period of up to 120 days. After this time, all samples were subject to a comprehensive analysis including well-known techniques such as determination of the oxidation value via FTIR, neutralization number, water content, elemental composition, viscosity changes, simulated distillation and determination of changes and ageing products with GC-MS. However, no significant changes were observed, while standard oxidation stability tests showed decreasing stability performance with increased test rig duration time. In order to determine the grade of degradation at very slight, not yet detectable levels and to be able to detect possible precursor ions of ageing, high-resolution mass spectrometry measurements were performed. This technique revealed the detailed degradation of individual fuel components, at very low levels. Based on these findings, a correlation with the stability results of PetroOxy and Rancimat standard test methods was possible. It was shown that real life stress in a diesel hybrid has an impact on fuel stability. A differentiation of the degradation of biocomponents and additives in terms of effects on fuel stability was possible, although not detectable with conventional and standardized analytical methods. The combination of high[1]resolution mass spectrometry with stability tests can be applied to find correlations of fuel component degradation and may be a tool for optimization.