沉积物和原油中常见含氧化合物的分离分析

将沉积物抽提物和原油中复杂的非烃组成分离为酸性、中性I和中性Ⅱ3个馏分。各馏分经GC／MS分析证实羟酸和极性较大的多元醇和酮进入酸性馏分,一元酮、酯和直接一元醇进入中性馏分I,而甾醇类化合物进入中性瘤分Ⅱ。各类化合物分段清晰,没有同一化合物在不同馏分中出现的现象,且分离过程中各化合物的比例基本保持不变。本文选用地质体中今未见析出的二十二烯酸,5α（H）－雄甾－17－酮和5α（H）－3β－醇分别作为各馏分的内标化合物,定量效果好,并首次为甾醇类化合物找到了较理想的内标物。本方法经近百个样品的分离分析证实效果良好。     

柱色谱分离、气相色谱-质谱法定性分析F-T合成油中的含氧化合物

在柱色谱柱中填充100～200目的硅胶,以二甲亚砜为洗脱剂,将F-T合成油产物分离为烃类及有机含氧化合物两部分。采用气相色谱-质谱(GC-MS)对有机含氧化合物部分进行了分析,共鉴定出有机含氧化合物139种,并对其出峰规律进行了总结。     

陕北中低温煤焦油中含氧有机化合物的质谱分析

中低温煤焦油中含氧有机化合物的含量较高,其中诸多含氧有机化合物是高附加值的有机化学品。本研究采用气相色谱/质谱联用仪（GC-MS）和负离子模式电喷雾傅里叶变换离子回旋共振质谱仪（NIESIFTICRMS）分析了陕北中低温煤焦油中的含氧有机化合物（OCOCs）,旨在了解OCOCs的组成结构,为有效分离OCOCs提供科学依据。结果表明,用GC-MS检测到的OCOCs中,含1个氧原子（O₁,主要为芳酚）和2个氧原子（O₂）的化合物的相对含量分别为99.4%和0.6%;用NIESIFTICRMS检测到的OCOCs中碳原子数、氧原子数和芳环数范围分别为8～35、1～5和1～4,其中O₁和O₂占绝大多数;检测到的主要酸性OCOCs是苯酚、苯二酚和苯甲酸及其烷基取代物以及环烷和链烷酸,其中O₁的主要成分是1～4环的一元芳酚。GCMS与NIESIFTICRMS优势互补,是从分子水平上了解中低温煤焦油中OCOCs组成结构的有效工具。     

原油中芳香硫化合物形态分布的研究

建立了原油中多环芳香硫化合物形态分布的研究方法。采用氯化钯/硅胶配位交换色谱分离原油中的芳香硫化合物,并用气相色谱/质谱分析、气相色谱-硫化学发光检测法结合色谱保留指数,鉴定出原油中的100多个多环芳香硫化物,包括含烷基取代基的苯并噻吩和二苯并噻吩类硫化物。定量分析表明,二苯并噻吩类化合物的含量占芳香硫化合物总量的91%左右。该方法可用于不同来源的原油中芳香硫化合物的形态分布研究。     

气相色谱法测定汽油含氧化合物与苯

本着降低生产成本,开发仪器功能,提高工作效率,建立了双柱切换-反吹技术-气相色谱法(内标法)同时测定汽油中含氧化合物与苯。考察色谱阀的切换时间,柱温等因素对结果的影响,确定了最佳操作条件,同时对方法的精密度和重复性进行验证。结果表明,含氧化合物和苯的相对标准偏差为0.05%～0.2%,加标回收率分别为98.8%和96.7%,同时测定汽油中含氧化合物和苯方法的建立,其分析结果与石化标准方法分析结果一致。     

原油空气氧化前后多环芳烃组分的气相色谱-质谱分析

采用柱层析法对空气氧化前后的原油进行族组分分离,利用气相色谱-质谱(GC-MS)分离测定其芳香烃组分,分析多环芳烃组分的变化.结果表明,随着氧化过程的进行,烷基化多环芳烃占多环芳烃的含量从氧化前的71.5%增加到92.0%(175℃)和90.2%(225℃).轻质组分萘和菲的优势逐渐被重质组分艹屈取代.侧链少的多环芳烃比侧链多的更易氧化.氧化后,其他稠环化合物蒽、萤蒽、芘、苯并蒽含量降低,苯并萤蒽含量增加;苯并芘在175℃氧化后含量降低,而在225℃氧化后含量增加.与此同时,175℃氧化后生成了原油所不含有的三芳甾烃、联苯和苯并呋喃.     

含氧化合物选择性检测器的研制及应用

介绍了一种含氧有机化合物选择性检测器的原理、装置及其应用。裂解反应器温度在等于或高于1150 ℃时,可使有机化合物完全裂解,裂解率约为99.5%。其中含氧化合物裂解产生的一氧化碳在甲烷化微型反应器中转化为甲烷后,在气相色谱-火焰离子化检测器(GC-FID)上有所响应,其响应值与化合物中的氧含量成正比,而不含氧的碳氢化合物则没有响应,从而使含氧化合物得到选择性检测。甲烷化微型反应器转化率达到95%以上,并可再生使用。在完全裂解状态下,正丁醇的线性范围为0.440-243.000 g/L,最小检测量为440     

碱液萃取前后原油中酸性化合物组成的高分辨质谱分析

采用改进的碱液萃取方法分离杜巴原油中的酸性化合物(主要是环烷酸),通过高分辨质谱分析萃取过程中不同组分酸性化合物组成,以研究碱萃取前后酸性化合物的分布与组成特征。实验结果表明,电喷雾傅立叶变换离子回旋共振高分辨质谱(ESI-FT-ICR-MS)是分析原油中酸性化合物的强有力的手段;酸性化合物分布于碱萃取前后的各个组分中,但其组成有明显的差异,碱液萃取出的石油酸主要是相对分子质量小于500的酸性组分,增加反萃取溶剂的用量和极性有利于脱除萃取物中的非碱性氮化合物,对石油羧酸的组成影响不大。     

液相色谱-质谱联用法测定血液中全氟化合物

研究了快速溶剂萃取-液相色谱/质谱联用技术测定血液中PFAAs的方法。血液样品经过冷冻干燥,利用加速溶剂萃取的方法,最后使用液相色谱-质谱仪分析检测PFAAs成分。方法的回收率为74.6%~128.8%,检出限为1.10~25.1 ng/L。通过对珠江三角洲地区人群血液样本的分析,发现∑9PFAAs的浓度为26.8~557 ng/g,平均值为176±90.1 ng/g。血液中PFAAs的主要成分以PFHxA和PFOS为主,分别占血液中PFAAs浓度的20.97%和66.98%。人群血液中最常见和浓度最高的PFAAs是PFOS,而PFOA浓度相对较低。     

Determination of Lead and Nickel in Saudi Arabian Crude Oils by ICP/MS Using MIBK for Sample Pretreatment

Abstract

Inductively coupled plasma/mass spectrometer (ICP/MS) has been used for the determination of lead and nickel in different Saudi Arabian crude oils. MIBK-nitric acid extraction system is used for sample pretreatment and compared to previously investigated sampling techniques.     

Simultaneous Determination of Trace Metals in Saudi Arabian Crude Oil Products by Inductively Coupled Plasma Mass Spectrometry (Icp/Ms)

Abstract

The inductively coupled plasma in combination with a mass spectrometer (ICP/MS) has been used for the determination of metals in different Saudi Arabian crude oils (Arab Berri, Arab heavy, Arab medium and Arab light). A previously investigated extraction method has been applied in the determination of metals in oil to the sub ppm level.     

Dimethylbenzothiophenes and methyldibenzothiophenes in crude oils from different sources

A method is presented for the identification and quantification of C₂-substituted benzothiophenes in crude oil. The method will enable analysis of the pattern of these compounds, for example as a basis for differentiating crude oils from one another (fingerprinting) and for investigation of their suitability as indicators of oil maturity. Here results are reported for five crudes from Iraq, Venezuela, Saudi Arabia, the former Soviet Union, and the North Sea. The aromatic fraction of the crudes was oxidized and the dioxides of the heterocycles separated according to the number of carbon atoms in the side chains. The final separation was by capillary GC with atomic emission or flame ionization detection. A fluorinated analog was synthesized and used as internal standard. The concentrations of 2,3-, 2,4-, 2,7-, and 3,7-dimethylbenzothiophene ranged between 11 and 272 ppm. Three other dimethylated benzothiophenes present in lower amounts were also identified.     

Trace Metals Determination by Wet Ashing ICP/MS in Saudi Arabian Crude Oils

Abstract

The effect of metallic traces present in crude oils has raised a major concern to develop aquantitative analytical method. A Wet-Ashing procedure has been used for sample pretreatment to determine Al, Cd, Fe, K, Li, Mn, Ni, Pb, Sn and V in five (5) Saudi Arabian crude oil samples as multi-elements by Sciex elan ICP/MS. The relative standard deviation was found not more than 3% for five replicate samples.     

Oil spill identification by high-speed HPLC

The use of high-speed HPLC in oil spill identification problems has been evaluated in terms of analysis time and reliability. The aromatic fraction was analyzed by reverse-phase chromatography on a 3 μm packing, with detection at 210 and 287 nm, in less than 20 minutes. The profiles exhibited by several Spanish and Middle East crude oils were differentiated by simple statistical parameters. The effect of environmental weathering on the samples has also been investigated. An Arabian light crude oil was still identifiable after four months' simulated marine weathering.     

Adsorptive interaction between nitrogen compounds and organic and/or mineral phases in subsurface rocks. Models for compositional fractionation of pyrrolic nitrogen compounds in petroleum during petroleum migration

The results are reported of a range of laboratory chromatographic fractionation experiments with synthetic model compounds and a petroleum pyrrolic nitrogen fraction. Reversed phase separation of pyrrolic nitrogen compounds was governed mainly by the number of carbon atoms in the molecule, with little selectivity toward different positional isomers, whereas normal phase separation of the compounds could be explained in terms of steric effects related to alkylation position. Comparison of experimental results from model compounds with observations made previously using sets of natural samples taken from sedimentary basins clearly suggests adsorptive interactions between organic and mineral phases are involved in the compositional fractionation of pyrrolic nitrogen compounds in petroleum during migration. Detailed studies of the effects of petroleum migration on the molecular distribution of petroleum pyrrolic nitrogen compounds may provide useful, quantifiable, migration-related geochemical parameters.     

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.     

臭椿籽挥发油的化学成分分析

采用水蒸气蒸馏法对甘肃天水产的臭椿籽挥发油进行提取,挥发油得率约为2．1％(w);用气相色谱-质谱联用技术对挥发性成分进行了分析,鉴定了43个化合物,占挥发油相对含量的96．3％;主要成分为脂肪酸及酯、脂肪烃及甾族化合物,其中含量较高的有亚油酸、油酸、蓖麻酸和蓖麻酸甲酯。     

几种吸附剂对工业级粗四氢呋喃中丁醛的脱除效果研究

本文以硅藻土、分子筛、ＫＯＨ、ＮａＯＨ作为吸附剂,获得了脱除工业级粗四氢呋喃（ＴＨＦ）中丁醛的最佳温度为４８℃。在固定床反应器中,除醛以ＫＯＨ为佳,在釜式反应器中,以ＮａＯＨ为佳。     

Dewatering of crude oil emulsions 1. Rheological behaviour of the crude oil—water interface

Rheological properties of Buchan crude oil—water interfaces have been determined using a biconical bob rheometer. The effects of temperature and the presence of surface-active demulsifiers on film characteristics have been evaluated. Free oscillation and creep modes have been used, depending on the relative viscoelastic behaviour of the films. Film ageing is particularly significant, whilst temperature and the nature and concentration of any demulsification chemicals also contribute significantly. Further detailed understanding of interfacial film rheology is considered to be desirable for a complete appreciation of the stability of water-in-crude oil emulsions.