原油裂解过程中正构烷烃的组成变化特征及其地球化学意义  

Compositional characteristics and geochemical significance of n-alkanes in process of crude oil cracking

作　　者：唐小强[1,2] 黄光辉[1,2] 张敏 韩金平[1,2] 李碧 

机构地区：[1]长江大学教育部油气资源与勘探技术重点实验室 [2]地球化学系,湖北荆州434023

出　　处：《地学前缘》2009年第6期372-378,共7页Earth Science Frontiers

基　　金：国家"十五"重点科技攻关项目(2004BA616A02-01-01-03)

摘　　要：采用高温模拟技术,对原油样品进行模拟实验,并对其裂解过程中正构烷烃的组成和变化特征进行了地球化学研究。结果表明,原油大量裂解生成气态烃之前,原油中的高分子量正构烷烃已经开始裂解,以C1+5烃类裂解成C6～C14化合物为主。随成熟度的增加,C6～C14化合物进一步转化为C1～C5化合物,并伴随苯系物的产出,最终形成甲烷和裂解沥青。在正构烷烃的裂解过程中,苯及其同系物的丰度呈明显增加趋势,可以作为原油裂解程度的潜在判识标志。此外,利用同样的实验条件对正十六烷进行了对比模拟实验,其产物的组成和变化特征与原油中正构烷烃的基本相同。The simulation experiments with crude oil samples have been performed in laboratory by using high temperature simulative techniques,and the characteristics of change of compositions have also been analyzed by geochemical methods in the cracking process.The results indicate that before a large number of gaseous hydrocarbon being generated by cracking of crude oil,the n-alkanes of high molecular weight from crude oil has already begun to be pyrolyzed,and C＋15 hydrocarbon mainly cracked into C6-C14.With increasing maturity,C6-C14 is further transformed into C1-C5,accompanied by the output of benzene,ultimately forming methane and cracking bitumen.In the pyrolysis of n-alkanes process,abundance of benzene and its homologue show significantly increasing,which can be used as potential distinguishing marks of crude oil cracking.Besides,comparative simulation experiments on n-hexadecane have been performed in laboratory by the same experimental condition,and it shows that the characteristics of change of compositions are basically the same as that of n-alkanes in crude oil.

关 键 词：原油裂解 模拟实验 正构烷烃 正十六烷 苯系物 

分 类 号：P618.13[天文地球—矿床学]