不同基属FCC油浆中芳烃结构组成分析

Structure and Composition of Aromatics in Fluid Catalytic Cracking Slurry Oils From Different Crudes

为实现催化裂化(FCC)油浆的高附加值利用,研究了不同油浆窄馏分中芳烃的结构和组成变化。以中间基属和石蜡基属FCC油浆的抽出油为原料,采用实沸点减压蒸馏切割得到7个窄馏分,以改进的Brown-Ladner(B-L)法和全二维气相色谱/飞行时间质谱为表征手段,考察了2种油浆各窄馏分中芳烃的结构组成变化。结果表明:中间基属的青岛炼化催化裂化油浆(QD-FCC油浆)以3~5环芳烃为主,而石蜡基属的兰州炼化催化裂化油浆(LZ-FCC油浆)以2~4环芳烃为主,石蜡基属LZ-FCC油浆的总饱和碳及环烷碳分率大于中间基属QD-FCC油浆。2种油浆中三环芳烃主要是渺位缩合的菲类和氢化苯并蒽类化合物;四环芳烃以渺位缩合的苯并蒽类化合物为主,且含有部分迫位缩合的芘类化合物;五环芳烃以迫位缩合的苯并芘类化合物为主,石蜡基属LZ-FCC油浆中的五环芳烃含量远远小于中间基属QD-FCC油浆。

To study the structure and composition of aromatics in different narrow fractions of slurry oils,the extracted oils from intermediate-base and paraffinic-base catalytic cracking(FCC)slurry oils were cut into seven narrow fractions by vacuum distillation.Improved Brown-Ladner(B-L)method and comprehensive two-dimensional gas chromatography/time flight mass spectrometry(GC×GC-TOF MS)were used to investigate changes of aromatics composition and structure in each narrow fraction from the above two different slurry oils.Experimental results showed that the intermediate-base slurry oil from Qingdao Refining and Chemical Company(QD-FCC slurry)is mainly composed of 3-5 ring aromatics,but the paraffinic-base slurry oil from Lanzhou Petrochemical Company(LZ-FCC slurry)is mainly composed of 2-4 ring aromatics.It was found that the ratio of saturated-carbon over naphthenic-carbon of LZ-FCC slurry oil is higher than that of QD-FCC slurry oil.For both the above FCC slurry oils,tricyclic aromatics mainly include phenanthrene and dihydrobenzanthracene compounds,tetracyclic aromatics mainly benzanthracene compounds and a few pyrene compounds,and pentacyclic aromatics are mainly benzopyrene compounds.It was also be observed that pentacyclic aromatics from LZ-FCC slurry oil are much less than those from QD-FCC slurry oil.