Screening the origin and weathering of oil slicks by attenuated total reflectance mid-IR spectrometry

The combination of attenuated total reflectance-fourier transform mid-infrared spectrometry (ATR-FTMIR) and multivariate pattern recognition is presented as a fast and convenient methodology to ascertain the source product an oil slick comes from and to evaluate the extent of its weathering. Different types of hydrocarbons (including crude oils, several heavy distillates and the Prestige's heavy fuel oil) were spilled on metallic containers designed ad hoc and their fate monitored by ATR-FTMIR. Not only environmental conditions were considered for weathering but artificial IR- and UV-irradiation. Pattern-recognition studies revealed that the different hydrocarbons clustered at different locations on the score plots and that the samples corresponding to each oil became ordered according to the extent of their weathering. Among them, fuel oil samples coming from the recent disaster of the Prestige tanker off the Galician shoreline showed a distinctive behaviour. Comparison of natural-, IR- and UV-weathering of a crude oil showed that IR solar radiation can be important in oil-weathering, in addition to broadly-reported UV degradation.     

Identification and Linkage of Tarballs from the Coasts of Vancouver Island and Northern California Using GC/MS and Isotopic Techniques

During January and February 1996, a significant number of tarball/patty incidents occurred along the coasts of Vancouver Island, Washington, Oregon, and California. Samples of the tarballs were collected from the affected beaches and analyzed by gas chromatography/mass spectrometry (GC/MS) and gas chromatography/flame ionization detector (GC/FID) using a tiered analytical approach developed for determining the origin of oils. Selected samples were further analyzed using a carbon isotopic technique. Also, the relative abundances of a large number of “source-specific marker” compounds, in particular alkylated series of polycyclic aromatic hydrocarbons within the same alkylation isomeric groups, were compared. Results of the analysis revealed that (1) California/Oregon samples were chemically similar and consistent with the same source. They were identified to be bunker type fuel; (2) The tarball samples collected from British Columbia and Ocean Shores, Washington were chemically similar and consistent with the same source (also bunker type fuel). They were found to be similar to but may have a source different than the California/Oregon samples; (3) The source of the tarball/patty samples was neither Alaska North Slope oil nor California Monterrey Miocene oil; (4) The spilled oil samples have been highly weathered since release, and the California samples were more heavily weathered than the British Columbia samples.     

水上溢油的气相色谱-质谱法鉴别

利用气相色谱－质谱法分析水上溢油样品和可凝溢油源样品,通过比较溢油样品和可疑溢油源样品的总离子流图的轮廓、m/z 191和m/z 217质量色谱图指纹和姥鲛烷（Pr)与峰面积比值APr/APh,建立了水上溢油的GC－MS鉴别方法。     

Monitoring photooxidation of the Prestige's oil spill by attenuated total reflectance infrared spectroscopy

The recent release of ca. 70,000 tonnes of a heavy fuel oil from the Prestige-Nassau carrier along the Spanish northern coast, mainly along Galicia, was monitored using attenuated total reflectance—mid IR spectrometry. The fuel was characterized and differentiated from 10 products commonly transported along the Galician coast (and their series of weathered samples) using factor analysis. The Prestige's fuel was weathered under natural conditions and under infrared radiation to study its evolution on time. A correlation was established using the 1690-1700 cm⁻¹ carbonyl peak, where from it was deduced that IR radiation weathered the product two times faster than natural conditions. The use of 10 weathering indexes was carried out to confirm the main patterns given by factor analysis and to seek out which main functional groups and structures increased or decreased during weathering. It was found that the carbonyl and sulphoxide indexes varied greatly, as well as the total aromaticity and long chains ones. The substitution-related indexes pointed out that highly substituted aromatic structures increased although the total amount of isolated CH groups in aromatic structures reached a plateau.     

相选择性凝胶因子及其在油品污染处理中的应用研究进展

近年来含油污水及海上油品泄漏问题日益严重,威胁着人类的生存环境和海洋生态环境。相选择性凝胶因子因其制备简单、生物相容性好、快速高效、可重复利用等优点为油品污染处理提供了新选择。本文首先介绍了相选择性凝胶因子的分类和自组装机理及相选择性凝胶因子的发展现状,重点对小分子凝胶因子进行了阐述,其中小分子凝胶因子包括氨基酸类、有机酸及其盐类、胆固醇类和糖类衍生物类等,并对有机高分子凝胶因子做了简单介绍;最后对相选择性凝胶因子的发展做出了展望。     

A study of a crude oil spill site for selected metal concentrations remediated by a controlled burning in Southwest Louisiana

On August 17, 2002 an oil spill occurred at the Chevron Texaco No. 2 Bayou Tank Battery in the Sabine National Wildlife Refuge, in Southwest Louisiana. The spill covered approximately 3.5 acres of the surrounding marsh. A controlled and in-situ burn of the oil was conducted on August 20, 2002 along with some post-burn “mopping up” on the following day. Within a few days after the burn the growth of new vegetation was observed. A year after the burn, the affected marsh seemed to be no different from the rest of the marsh in the area, as if no spill or burn ever occurred. Analysis of the oil from the No. 2 Bayou Tank Battery showed that there were very low (below detection limit of ICP-OES), if any, concentrations of selected trace metals. Soil cores and grass samples were taken on December15, 2003 and July 15, 2004 from the Sabine National Wildlife Refuge oil spill site for metal determination and compared to cores and grasses taken from the surrounding marsh and confirmed that there was no increase in concentration of any metal that was examined as a result of the oil spill or controlled burn.     

阴阳离子表面活性剂体系超低油水界面张力的应用

通过阴阳离子表面活性剂复配,在实际油水体系中获得了超低界面张力.通过在阴离子表面活性剂分子结构中加入乙氧基(EO)链段,以及采用阴阳离子加非离子型表面活性剂的三组分策略,有效解决了混合表面活性剂在水溶液中溶解度问题.进而研究了阳离子表面活性剂结构、非离子表面活性剂结构、三者组分配比、表面活性剂总浓度等因素对油水界面张力的影响,从而在胜利油田多个实际油水体系中获得了较大比例范围和较低浓度区域的油水超低界面张力,部分体系甚至达到了10-4 mN·m-1.由于阴阳离子表面活性剂间强烈的静电吸引作用,相关体系具有很好的抗吸附能力.经过石英砂48 h吸附后,体系仍然具有很好的超低界面张力.     

Fingerprinting and source identification of an oil spill in China Bohai Sea by gas chromatography-flame ionization detection and gas chromatography–mass spectrometry coupled with multi-statistical analyses

This paper describes a case study in which advanced chemical fingerprinting and data interpretation techniques were used to characterize the chemical composition and determine the source of an unknown spilled oil reported on the beach of China Bohai Sea in 2005. The spilled oil was suspected to be released from nearby platforms. In response to this specific site investigation need, a tiered analytical approach using gas chromatography–mass spectrometry (GC–MS) and gas chromatography-flame ionization detection (GC-FID) was applied. A variety of diagnostic ratios of “source-specific marker” compounds, in particular isomers of biomarkers, were determined and compared. Several statistical data correlation analysis methods were applied, including clustering analysis and Student's t-test method. The comparison of the two methods was conducted. The comprehensive analysis results reveal the following: (1) The oil fingerprinting of three spilled oil samples (S1, S2 and S3) positively match each other; (2) The three spilled oil samples have suffered different weathering, dominated by evaporation with decrease of the low-molecular—mass n-alkanes at different degrees; (3) The oil fingerprinting profiles of the three spilled oil samples are positive match with that of the suspected source oil samples C41, C42, C43, C44 and C45; (4) There are significant differences in the oil fingerprinting profiles between the three spilled oil samples and the suspected source oil samples A1, B1, B2, B3, B4, C1, C2, C3, C5 and C6.     

Determination of Anionic Surfactant Turkey Red Oil by Capillary Electrophoresis with Direct UV Detection

A method using capillary electrophoresis with direct UV detection has been developed and validated for the determination of Turkey Red Oil (sulfonated castor oil). The highest performance with respect to separation efficiency and analysis time was achieved with 30 mM Tris (pH 8.0) buffer containing 7.5 mM HP-β-CD. The feasibility of the proposed CE method for the analysis of Turkey Red Oil surfactant in industrial water samples is demonstrated. Spiking of real samples gave recoveries between 90 and 106%. The CE results were compared with that obtained by GC-MS. It was concluded that CE can be a good alternative for fast determination of Turkey Red Oil component distribution in industrial process waters with no sample preparation other than dilution. However, the method sensitivity is not satisfactory for monitoring surfactant level in a waste effluent stream.     

Spectrochemical study for the in situ detection of oil spill residues using laser-induced breakdown spectroscopy

Laser-induced breakdown spectroscopy (LIBS) has been used to identify the differences or similarities between crude oil and fuel residues. Firstly, a man portable LIBS analyzer was used for the on-site environmental control and analysis of the oil spill from The Prestige. An exhaustive analysis of crude oil and oil spill residues (collected during the field campaign in the Galician Coast) was performed in the laboratory. Characteristics elements in petroleum such as C, H, N, O, Mg, Na, Fe and V were detected. In addition, contributions from Ca, Si and Al in the composition of residues have been found. The use of intensity ratios of line and band emissions in the original fuel (crude oil) and in the aged residues allowed a better characterization of the samples than the simple use of peak intensities. The chemical composition between the crude oil and the fuel residues was found completely different. As well, a statistical method was employed in order to discriminate residues. Although significant differences were observed, no conclusions in terms of age and provenance could be reached due to the unknowledgment in the origin of the samples.