选取中国不同产地的17种原油, 考察了原油环己烷溶液3个浓度(5, 500和5 000 mg·L-1)的同步荧光光谱(SFS)特征, 测定了其中4种原油自然风化1, 3, 5, 10, 15和35 d的三个浓度油溶液的SFS, 并利用原油的SFS特征结合主成分分析进行了溢油鉴别研究。 结果表明: 原油溶液的浓度不同, 光谱峰位置和数目均不相同, 随着浓度的增大峰位发生红移, 5, 500和5 000 mg·L-1的油溶液分别在激发波长260～460, 290～550和400～850 nm有特征峰; 不同原油的500 mg·L-1油溶液的SFS具有较大差异, 而同种原油的SFS具有较高的相似性, 具有更好地区分原油的能力。 以500 mg·L-1的油溶液的SFS作为油样的光谱特征鉴别油品, 将一个风化油作为未知油样, 用主成分分析法处理17种原油和未知油样的同步荧光光谱特征, 主成分(PC1对PC2)得分投影图显示未知油样与油样NH-1, BH-3, BH-8和LT-2相似, 而主成分(PC2对PC3)得分投影图显示未知油样与油样NH-1最相似, 鉴别结果与实际情况相符。 可见, 采用高浓度(500 mg·L-1)同步荧光法鉴别溢油快速可靠, 在实际溢油鉴别中具有潜在的应用价值。

In the present paper, a tentative study was made to identify spilled oils using synchronous fluorescence spectrum (SFS). Seventeen crude oil samples from different areas in China were studied. SFS of oil solutions with three concentrations, which were 5, 500 and 5 000 mg·L-1, were analyzed. The number and position of SFS peaks were different for the different concentrations of oil solutions. Oil solutions of 5, 500 and 5 000 mg·L-1 had characteristic peaks in excitation wavelength 260～460, 290～550 and 400～850 nm, respectively. In order to study the weathering effect on SFS, four crude oils were also set outdoors for weathering experiment and SFS of weathered oils after 1, 3, 5, 10, 15 and 35 d were determined. All the SFS of original and weathered oils were analyzed using principal component analysis (PCA). The principal component scores charts showed that the SFS of the oil solution of 500 mg·L-1 had better distinguishing ability than the other two concentrations. Thus SFS of 500 mg·L-1 between 290 and 600 nm were selected as spectrum feature of crude oils and used to build oil fingerprint data base for identifying crude oils. Taking one oil sample with unknown source among the seventeen crude oils as a case study, SFS were analyzed by PCA to find the origin of the unknown crude oil. The results draw a conclusion that SFS of high concentration solution (500 mg·L-1) may become a useful means in spilled oils identification.