Compositional Analysis of Waxy Distillate Fractions by 1H and 13C NMR Spectroscopy

Distillate fractions having boiling ranges of 270-320°C and 320-370°C derived from Heera and Panna crudes are characterized for their average structural parameters using n-d-M method as well as ¹h and ¹³C NMR spectroscopy. It is observed that these fractions contain predominantly saturated carbons. Aromatic carbons in them decreases with the increase in boiling range. Methyl substituents are predominant compared with other alkyl substituents in these distillate fractions.     

元素分析仪测定原油、重质油中的氮含量

主要论述了利用ＣＨＮ－ Ｏ－ ＲＡＰＩＤ 元素分析仪测定原油、重质油的氮含量。采用本实验室研制的低含氮量的试剂制作工作曲线,氮的动态检测下限为０－０２ ｍｇ 。评价了方法的准确性,研究了空白的影响,同时考察了样品的测量精密度。     

含蜡原油粘弹性与微观结构间关系的研究现状与分析

含蜡原油粘弹性源于其内部的蜡结晶量与复杂的蜡晶形态及结构,但二者间的定量关系仍未建立起来.在概述含蜡原油蜡晶形态和结构的定量表征与总结粘弹性研究的基础上,进一步分析了二者间定量关系的研究现状,并指出了存在的问题与进一步的研究课题.建议在悬浮液及凝胶体系的有关理论框架下,结合大量的试验研究,利用数理统计分析方法,深入探索粘弹性与蜡晶形态及结构间的定量关系,以丰富对原油流变学微观机理的认识.     

三肇凹陷低熟原油^13C—NMR谱特征

本语通过低熟原油与成熟原油在＾１３Ｃ－ＮＭＲ谱图形态、参数特征的分析，得中由分子结构特点来区分低熟原油和成熟原同。并指出低熟油可能主要为成岩作用早期藻类物质成烃的结果。     

含蜡原油相态转换边界值的计算

对含蜡原油相态转换边界值的计算进行描述，同时用实例进行数值分析，近年来，为提高原油产量，对油田开发不断地进行研究，同时也发展了许多新方法，在油层不断开采的情况下，由于复杂的渗流变化，伴随产生了油气相态转变和油气中各项密度和粘度的变化，因此，研究油层中油层相态转变，保持高压气体和富气来驱动原油开采是非常重要的。     

Rheology of Doped Nigerian Niger-Delta Waxy Crude Oil

Abstract

Precipitation and deposition of wax, which usually results from temperature lowering, has detrimental effects on petroleum industry operations. To appreciate and understand the physicochemical mechanics of wax precipitation, rheological experiments were carried out on three doped and undoped Nigerian waxy crude oils. The characteristic shear stress straining rate shows an initial constant shear stress below 50 sec^?1 shear rate, followed by a gradual increase above 50 sec^?1 which is indicative of energy consumption in the partial break-up of wax matrix bonds. Doping greatly ameliorates the rheological properties and pour points of the crude oils. The Bingham plastic model excellently fit the experimental data, with a correlation coefficient ≥ 0.97721.     

降凝剂在海上含蜡原油管道中的应用

降凝剂在海上和陆上含蜡原油输油管道上的应用结果表明,降凝剂可降低含蜡原油凝点,改善含蜡原油低温流动性能,延长停输时间,减小停输再启动压力等,特别适用于海洋和沙漠中不宜建中问加热站的含蜡原油管道。对降凝剂的作用机理及其在海底管道的应用特点进行了介绍和论述。     

^13C NMR and ^1H NMR Spectroscopic Analysis of Adansonia digitata,Albizia lebbeck and Daniellia ofiveri Oils

Oils of AD （Adansonia digitata）, AL （Albizia lebbeck） and DO （Daniellia oliveri） were studied using ^13C NMR （nuclear magnetic resonance） and ^1H NMR. The gated decoupled high resolution ^13C NMR spectra revealed the presence of both saturated and unsaturated triacylglycerides. However, there is a higher percentage of unsaturation in AL seed oil. The peaks at 0.7 ppm to 0.9 ppm which correspond to the terminal methyl groups in the fatty acid and that at 1.2 ppm to 1.3 ppm are more intense and bigger in DO which show that it is more saturated than AD and AL oils. The results obtained by ^13C NMR and ^1H NMR are compared favorably with those obtained by gas chromatographic analysis.     

Experimental Research on the Wax Crystal Particle Size Distribution of Waxy Crude Oil

The total settled mass of waxy crude oil has a close relationship with the particle size distribution of wax crystals. Wax crystal images of four kinds of crude oils were obtained with OPTIPHOT2-POL polarizing microscope. The wax particle size distribution was confirmed by image processing and data analysis. The results strongly suggest that wax particle size correspond to gamma distribution. Moreover, the range of wax particle size distribution expands with the increasing of temperature.     

双取代烷基苯的核磁共振碳谱分析

在导出双取代烷基苯的化学位移加和规律的基础上,归属了烷基化产物长直链烷基和甲基双取代烷基苯的核磁共振碳谱。以单取代的长直链烷基苯为基础,根据δ_C=δ_(mono)+∑Z_i(δ_C 为双取代烷基苯中各碳原子的化学位移;δ_(mono)为单取代长直链烷基苯中各碳原子的化学位移;Z_i为化学位移增量)可计算出双取代烷基苯中各碳原子的化学位移。对于芳碳原子,甲基收代位的碳和甲基取代位的邻位、间位、对位碳的化学位移增量分别为+9.13,+0.63,-0.23,-3.15。对于长直链烷基碳原子,当两个烷基处于苯环的间位时,甲基取代引起的α位和β位烷基碳的化学位移增量分别为-0.04和+0.08;当两个烷基处于苯环的对化时,甲基取代引起的α位和β位的烷基碳的化学位移增量为-0.43和+0.01。烷基化产物中未见邻位双取代物。在谱峰完全归属的基础上,用7种方法测定了烷基取代位置异构体或芳环取代位置异构体的组成。     

Characterization of Asphalt Fractions by NMR Spectroscopy

Abstract

Petroleum asphalt was separated into saturates, naphthalene aromatics, polar aromatics, and asphaltenes using the Corbett method. These asphalt fractions were characterized by H-1 and C-13 nuclear magnetic resonance spectroscopy (NMR). The spectra of saturates illustrate only traceable quantities of aromatic hydrogen and aromatic carbon. Naphthalene aromatics, polar aromatics, and asphaltenes all have broad bands in the aromatic regions of both H-1 and C-13 NMR spectra. These broad bands demonstrate the presence of polycondensed aromatic rings present in the structure of naphthalene aromatics, polar aromatics, and asphaltenes. Based on available literature, numerous NMR resonance bands are identified. The quantitative estimations for various kinds of protons and carbons in the asphalt fractions are compared.     

Characterisation of an algerian asphaltene by 1H and 13C CPMAS NMR,DEPT and ESI mass spectroscopy

Quantitative liquid 1H and solid 13C CPMAS NMR spectroscopy were used in combination with qualitative DEPT (Distortionless Enhancement by Polarization Transfer) and liquid 13C NMR to investigate the molecular structural parameters of an Algerian asphaltenes. The molecular weight of the asphaltene ionisable species determined by positive Electro Spray Ionization mass spectrometry ESI was around 390 Da. The results indicate that the representative molecular structure of the asphaltenes contains PAH (Poly-aromatic hydrocarbon) core of 4–5 rings. The combination of 13C NMR/DEPT constitutes a good route for characterizing the chemical functions of asphaltenes.     

降凝剂对高蜡稠油的改性效果及机理研究

实验研究了工业品原油降凝剂WHP改善含蜡56.9%、其中96.6%为正构烷烃的胜利郑王庄稠油流动性的效果。WHP含乙烯/醋酸乙烯/乙烯醇嵌段聚醚三元共聚物30%-35%。在60℃将WHP加入稠油中,测定其凝点和32℃、0-42.6 s^-1范围5个剪切速率下的黏度,均随WHP加量的增加（50-300 mg/L）而降低,200 mg/L为最佳加量,在该加量下0.32 s^-1黏度由34.16 Pa·s降至79.2 mPa·s,凝点（℃）、屈服值（Pa）、稠度系数（Pa·s^n）分别由49.0、32.42、31.57降至39.5、0.1297、0.02142,流型指数由0.1176升至0.9790。由黏温曲线求出,加入200mg/L WHP使该稠油析蜡点由65℃降至58℃,反常点由70℃降至50℃。根据空白和加剂原油扫描电镜照片显示的蜡晶形态,利用共晶机理分析讨论了WHP这种高分子表面活性剂的降凝、降黏、改善流动性的作用。图3表3参5。     

~(13)C NMR方法分析聚乙烯催化剂

通过对交叉极化共振13C NMR实验的共振参数进行实验优化,定性分析了聚乙烯催化剂的组分,其中包含丁氧基钛、乙氧基钛和环氧氯丙烷。利用13C NMR的交叉极化时间与不同碳原子吸收峰的峰面积关系及卷积法可对催化剂中的组分进行定量分析。采用13C NMR方法对不同活性的聚乙烯催化剂进行了表征。表征结果显示,催化剂活性随催化剂中乙氧基含量的增大、丁氧基含量的减少而增大。     

W/O型含蜡原油乳状液胶凝体系的屈服特性

在恒定剪切应力和剪切应力线性增加2种加载模式下,研究了油包水（W/O）型含蜡原油乳状液胶凝体系在凝点温度附近的屈服行为。以原油乳状液胶凝体系的屈服应变、屈服剪切速率为特征量,分析了剪切应力加载条件、加载量和胶凝体系含水率对含蜡原油乳状液胶凝体系屈服特性的影响规律。引用屈服应变比例系数的概念,分析了不同恒温静置时间后含蜡原油乳状液胶凝体系结构恢复程度及其影响因素。研究发现：屈服应变可作为W/O型含蜡原油乳状液胶凝体系屈服的判据;增大原油乳状液胶凝体系含水体积分数,屈服应变增大,屈服剪切速率减小,体系恢复度增加。增大剪切应力加载量或剪切应力增加速率,原油乳状液胶凝体系屈服剪切速率增大,该体系的结构恢复程度变差。     

聚合物/微纳米复合含蜡原油降凝剂的研究进展

含蜡原油中蜡分子的结晶析出会使原油的低温流变性显著恶化,降低原油管输的安全性和经济性.添加少量的聚合物型降凝剂能够改变蜡分子的结晶习性,改善原油的宏观流动性.加降凝剂原油的凝点越低、低温黏度越小,意味着输送的能耗越低、安全性越高,因此人们对原油降凝剂的降凝降黏效果追求是无止境的.利用不同的微纳米颗粒,研制高效的聚合物/...     

气相色谱-飞行时间质谱表征馏分油芳烃分子组成的馏程分布

建立了气相色谱-飞行时间质谱表征馏分油芳烃分子组成馏程分布的分析方法。以不同环数芳烃标样的沸点-色谱保留时间关系曲线为芳烃试样色谱图馏分切割的依据,利用此方法表征了试样Y中芳烃的分子组成、平均相对分子质量和平均结构的馏程分布。实验结果表明,各馏分段中芳烃的平均相对分子质量与此馏分段的温度呈良好的线性关系,相关系数为0.995 4,可由此预测芳烃试样在任意馏分段的平均相对分子质量;在相同馏分段中,芳烃不饱和度越高,平均碳数和平均相对分子质量越小,侧链碳率越低。该方法开拓了分子水平表征石油及其产品的新思路。     

An Experimental Study on Wax Deposition of Water in Waxy Crude Oil Emulsions

Abstract

The key factors affecting wax deposition of water-in-oil emulsion were studied experimentally using a cold finger device. Wax deposition characteristics of emulsions were obtained. The results showed that the wax deposition profile of emulsions as a function of temperature parameters was similar to that of single oil. However, the effect of the extent of water cut on wax deposition was obviously different at different temperatures. Furthermore, the relative mass of deposit was proposed and found independent of water cut, from which wax deposition rate at different water cuts could be predicted and the predicted values were in good agreement with experimental data.     

Structure Analysis of Paraffin Waxes by 13C-NMR Spectroscopy

Abstract

This paper reviews investigations into the composition of macro- and microcrystalline paraffin waxes, focused on the structure of these paraffin waxes. This paper describes a analytical method that gives massive information about the structure of the paraffin waxes, using a special ¹³C-NMR spectroscopy method. This method based on a characterization of ethene/α-olefine copolymers that exhibit a similar structure to that of paraffin waxes.     

用S—甲基化反应和^2H NMR,^13C NMR表征石油中有机硫的结构

提出用衍生物－ＮＭＲ表征石油中的有机硫结构的方法，在四氟硼酸银的存在下，分别用＾２Ｈ或＾１３Ｃ同位素富集的碘甲烷，把石油中的有机硫定量地转变为相应的甲基镀盐，然后用＾２ＨＮＭＲ和＾１３ＣＮＭＲ表征硫化物的结构，给出了一些模型甲工铳盐的＾２ＨＮＭＲ和＾１３ＣＮＭＲ化学位移值。分析结果表明，石油中噻吩类为苯并噻吩型等结构，硫醚为脂肪硫醚，二苯硫醚及α－萘基甲基硫醚等，阿拉伯原油样品中，大约７０％的硫化