关键词: 减压渣油, 超临界萃取残渣, 钌离子催化氧化, 烷基侧链, 聚亚甲基桥接链

Abstract:

Dagang vacuum residue (VR) and its supercritical fluid extraction and fractionation (SFEF) tailing were separated into four group compositions (SARA) by chromatographyThe molecular structural features of the asphaltenes from VR and SFEF tailing were investigated with ruthenium ion catalyzed oxidation (RICO)By means of GCMS and GC analysis, the homologous series of n-alkanoic acids (C₄—C₃₃) and α,ω-di-n-alkanoic acids (C₄—C_24) were detected and measured quantitativelyThe distribution of these carboxylic acids obtained from the oxidation reaction was useful in determining the distribution of polymethylene bridge bonds and alkyl side chainsThe results indicated that the molar concentrations of n-alkyl side chains and polymethylene bridges decreased with the increase of chain length, and were characterized by eventoodd carbon number preferenceSFEF tailing asphaltene had less C₂₅₊ but more C₁₇—C₂₅ n-alkyl side chain than VR asphalteneFurthermore, the polymethylene bridge concentration of VR asphaltene was about 25 folds of SFEF tailing asphalteneThe above information demonstrated that cracking reaction might occur in the SFEF process.

Key words: 减压渣油, 超临界萃取残渣, 钌离子催化氧化, 烷基侧链, 聚亚甲基桥接链