风城稠油中石油酸组成结构分析

摘要

Petroleum acids in Fengcheng heavy crude were separated by potassium hydroxide-ethanol aqueous solution extraction.The compositions and structures of petroleum acids were determined by elemental analysis,IR,NMR,ESI-MS,UV and Fluorescence Spectrum.The results show that the petroleum acid in Fengcheng heavy crude is mainly composed of dimers of mono-carboxylic acids with an average molecular weight of 665,the empirical formula is C43.51H78.47O3.78 with a hydrogen-carbon mole ratio of 1.80.The contents of naphthenic acids and aliphatic acids occupy 79.84％ and 20.16％,respectively.The contents of naphthenic acids with different structures (including 1 3 ring naphthenic acids,4-ring naphthenic acids/aromatic carboxylic acids,5-ring naphthenic acids/benzonaphthenic carboxylic acids with one ring,6-ring naphthenic acids/benzonaphthenic carboxylic acids with 2-ring)are close to each other,ranging from 11.00 ％ to 18.88％.Trace amount of 3-4 ring aromatic in petroleum acids are also observed.%由氢氧化钾-乙醇水溶液分离风城稠油中的石油酸,结合元素分析、红外光谱(FT-IR)、核磁共振(NMR)、电喷雾质谱(ESI-MS)、紫外光谱(UV-Vis)和荧光色谱等方法分析其结构组成.结果表明:风城稠油所含石油酸主要是一元羧酸二聚体,平均相对分子质量为665,平均分子式为C43.51H78.47O3.78,氢碳原子比为1.80;各类酸分布范围较广,其中,环烷酸含量最高,占79.84％,脂肪酸次之,占20.16％;环烷酸中一环环烷酸、二环环烷酸、三环环烷酸、四环环烷酸/芳环羧酸、五环环烷酸/芳环并一环羧酸和六环环烷酸/芳环并二环羧酸的含量相当,均在11.00％～18.88％之间.此外,还检测到微量3～4环的芳香结构物质.