Effects of composition distribution of catalytic oil slurry on optical texture of mesophase pitch

DAI Xiaoyu1 MA Yuanen1 XU Zhiming1 ZHANG Linzhou1 ZHAO Suoqi1 XU Chunming1

(1.State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing, China 102249)

【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;

【DOI】

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(Translated by ZHAO L)

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This Article

ISSN:0438-1157

CN: 11-1946/TQ

Vol 71, No. 06, Pages 2678-2687+2450

June 2020

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Article Outline

Abstract

  • Introduction
  • 1 Materials and characterization
  • 2 Results and discussion
  • 3 Conclusions
  • References