煤基费托航空燃料热氧化安定性研究

Study on thermal oxidation stability of coal-based Fischer-Tropsch aviation fuel

煤基费托燃料(FT)被认为是替代石油基航空煤油(RP-3)并可最早实现大规模应用的航空替代燃料,而氧化安定性是其能否应用于未来高性能发动机的一项重要指标。以RP-3为基准,研究了FT和50%质量掺混比的燃料(FT-RP-3 50%)在不同温度、时间下的热氧化安定性,并对氧化产物的色度进行了定量标定。采用层析方法分离并定性和定量了氧化产物中的有色组分。研究结果表明,燃料组成和反应温度是控制有色组分生成和转化沉积的主导因素。色谱分析结果表明,RP-3氧化产物中有色组分的成分主要为烷基萘(60.03%)和烷基苯酚(18.56%)类化合物,而FT氧化产物中有色组分的成分主要为含氧的脂肪族(81.06%)和脂环族(8.66%)类化合物。在RP-3中掺混FT,可使有色组分转化为沉积物的温度从175℃升高至250℃,明显改善了RP-3的热氧化安定性。

Coal-based Fischer-Tropsch fuel（ FT） is considered as a substitute for petroleum-based aviation fuels（ RP-3）,and which is also considered as the first substitute that can be applied commercially.Its oxidative stability is an important indicator to decide whether it can be applied to future high-performance engines or not. Based on RP-3,the thermal oxidation stability of the blending fuels with 50 ∶50 of mass ratio between FT and RP-3 is investigated at different reaction temperature and time. The chroma of the oxidation products is calibrated quantitatively,and the colored components in the oxidation products are separated and analyzed qualitatively and quantitatively by using chromatographic method. The results show that fuel composition and reaction temperature are the dominant factors to controll the formation and transformation of the colored components. Chromatographic identification indicates that the colored components in RP-3 oxidation products include mainly alkyl naphthalenes（ 60. 03%） and alkyl phenols（ 18. 56%） compounds,while those in FT are predominantly oxygen-containing aliphatic（ 81. 06%） and alicyclic（ 8. 66%） compounds. The addition of FT in RP-3 can improve the conversion temperature of colored components to sediments from 175℃ to 250℃,significantly improving the thermal oxidation stability of RP-3.