用X射线衍射图研究柴油低温流动改进剂的作用

通常,柴油中含有15%～30%的正构烷烃。在低温下,柴油中大分子量的蜡以晶体形式析出,可堵塞导管和滤清器,导致了柴油机供油的困难1]。柴油在低温下的流动性能不仅关系到柴油机燃料供油系统在低温下能否正常供油,而且与柴油在低温下的储存和运输等作业能否进行有密切的关系。加入低温流动改进剂改善柴油的低温流动性能,以其成本低,操作简便而成为解决柴油低温流动性能的首选方法,并在工业上得到广泛应用2]。柴油在低温下蜡的析出直至影响其流动性能的过程是一个蜡结晶的过程,由于蜡的组成复杂,其结晶过程也很复杂3]。用X射线衍射法分…

X-RAY DIFFRACTION STUDY ON PERFORMANCE OF DIESEL FLOW IMPROVER

Precipitation of n-alkanes in diesel affects cold flow property. With XRD pattern, shape of crystals is able to be studied. But XRD pattern has not been applied to investigation of precipitation of crystals of n-alkanes appearing in diesel. In this paper, XRD pattern of a series of diesel flow improver(DFI), wax and mixture of wax and DFI are analyzed. The relationship between character of XRD pattern and performance of DFI is studied. When sharp peak between 10°～30° is little, shape of peak is ordered and curve of peak is smooth, performance of DFI is better. XRD pattern of the mixture of wax and DFI shows noncrystalline structure has changed. Hence it might be considered crystallization procedure of wax be affected by DFI. This work is also helpful to the full understanding of the mechanism of DFI.