Composition and Structure of Wax in Diesel

The chemical composition and structure of crystallized wax in diesel at lower temperature was analyzed using gas chromatography and X-ray diffraction(XRD).Microscope with optical phase contrast was used to observe the shape of wax.Furthermore,the wax,being precipitated in diesel after adding cold improver T1804,was also investigated.The wax was mostly composed of alkanes,with carbon number not less than 16.Alkanes with higher carbon number crystallized more rapidly during the wax forming process.After adding the additives, the content of alkanes with higher carbon numbers in the crystallized wax was reduced.After adding the improver,the structure of wax is similar to n-tricosane and the average size of wax particles becomes smaller while the long-range order of wax increases based on XRD spectrum.The microscopic images revealed that the shapes of wax congeries changes from flake to branch when the cold improver was added.