Formation Mechanism and StructuralEvolution of Mesophase Pitch via Phase Separation

Abstract

Mesophase pitch is obtainedthrough a two-stage treatment method combining stirring and non-stirring heat treatment of thecatalytic cracking oil slurry. The structural evolution during the mesophase pitch forming process isanalyzed using phase separation and testing by X-ray diffraction, FourierTransform Infrared spectroscopy, and Thermogravimetric analysis. After a short period of non-stirring heattreatment, the solid-phase yield rapidly increases by 14.20 wt.%, reaching 46.70 wt.%. The softening point of the final mesophase pitch is all below 350℃. The increase in yieldand structural transformation are influenced by changes in the content ofquinoline insoluble, as evidenced by the presence of C-H out-of-plane bendingvibration at 670 cm^-1. Based on the observed changes in composition and structure, this studyproposes a hypothesis regarding the increase in mesophase pitch productionduring heat treatment.

Keywords

Mesophase pitch / Phase separation / Two-stage thermal polycondensation / FCC slurry

Author Contributions

H.G.: Investigation, Data curation, Writing—review & editing. Y.L.: Methodology. L.C.: Methodology. P.D.: Methodology. Y.Z.: Writing—editing, Resources. Y.F.: Writing—editing. W.L.: Writing—review & editing, Supervision, Resources, Funding acquisition.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Funding

This work was financially supported by the National Natural Science Foundation of China -Petrochemical Joint Fund Key Project (U22B20142), National Natural Science Foundation of China (22078347), Henan Provincial Joint Fund for Science and Technology Research and Development Program（No. 235200810021), Zhongke Technology Achievement Transfer and Transformation Center of Henan Province (2024101), Distinguished Professor of Henan Province (220508001), Foreign Talent Attraction Program of Henan Province (GZS2024023).

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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