原油饱和烃指纹的内标法分析

Oil Fingerprint Analysis of Saturated Hydrocarbon by Internal Standard Method

采用内标法建立了原油中正构烷烃、生物标志物(甾、萜烷类)的分析方法。确定了样品前处理方法和组分定性定量方法。讨论了柱层析分离能力。结果表明,所有饱和烃组分均流入第一部分流出液F1中,分离能力较为满意。对48种甾、萜烷类生物标志物组分以及姥鲛烷、植烷和正构烷烃等进行了定性确认,定性化合物数量多,信息量大,易于据此进行可靠的油指纹分析鉴别。32个正构烷烃组分相对标准差为1.2%～7.4%;45个生物标志物组分相对标准偏差为2.5%～9.2%。分析精密度较好,满足油指纹鉴别需要。正构烷烃回收率为73%～116%;生物标志物为84%～106%;回收率结果较为满意。正构烷烃方法检出限为7.0μg/g;生物标志物为0.65μg/g,满足原油样品分析要求。通过本方法对自不同和相同平台的原油样品进行饱和烃浓度分析,并采用浓度数据进行鉴别,结果与实际情况相符。

A method for analysis n-alkanes, steranes and terpanes in oil by internal standard method was established. Sample preparation, qualitative and quantitative method were confirmed. The column chromato- graphic fractionation ability was discussed. As results, all the saturated hydrocarbon were eluted into the first fract, the fractionation ability is satisfactory, n-Alkanes, pristane, phytane and 48 steranes and terpanes compounds were confirmed, contents of constituent information is enormous, so it＇s easy to get credible identi- fication result by this method. The precision, recovery and detection limit of the method were determined. 6 replicates sample were analysed by this method, the relative standard deviation of 32 n-alkanes and 45 biomar- kers compound is 1.3%-7.4% and 2.5%-9.2% respectively. The recoveris of n-alkanes is 73% -116%, those of biomarkers are 84% -106%. The detection limit of n-alkanes and biomarkers are 7.0 μg/g and 0. 65 μg/g, respectively, It can meet the requirements of oil analysis. 3 oil sample from differ- ent and same platform were analysed by this method, and distinguished with their concentration value, as a result, the conclusion was consistent with the fact.