Effects of composition distribution of catalytic oil slurry on optical texture of mesophase pitch
【Abstract】Using SLO-LH, SLO-SH and SLO-YN catalytic oil slurry as raw materials, mesophase pitch was prepared by thermal polycondensation method. The hydrocarbon composition distribution, boiling point distribution and nuclear magnetic structure characteristics of the oil slurry were systematically analyzed and related to mesophase pitch. The results show that the molecular weight and composition distribution of SLO-SH and SLOYN are relatively narrow. The mesophase pitch was prepared under the given reaction conditions of 430 °C and 0.7 MPa. The obtained mesophase texture is mainly composed of large-area domain and flow domain, and with less mosaic structure. The optical texture indexes (OTIs) of SLO-SH and SLO-YN are 45 and 50, respectively. Compared with SLOSH and SLO-YN, the hydrocarbon composition and boiling point distribution of SLO-LH samples are significantly evacuated. The mesophase obtained from SLO-LH is mainly composed of a mosaic structure and a small domain. The results show that concentrated distribution and high aromatic content are conducive to high-quality mesophase pitch with high yield and high OTI value. Separation of oil slurry components is a necessary way to prepare high-quality mesophase pitch and needle coke.
【Keywords】 catalytic oil slurry ; composition; separation; distribution; mesophase pitch; microstructure;
(Translated by ZHAO L)
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