Study of resin fraction of Nigerian crude oil using spectroscopic/spectrometric analytical techniques

Organics and trace metals of the resin fraction of Nigerian crude oil were analysed in order to characterise the fossil fuel. The crude oil samples were deasphaltened by n-pentane, while maltene fraction was fractionated into its components (saturates, aromatics and resin) using column chromatography. The organic compounds and elemental concentrations of the resin fraction were investigated using Fourier Transform Infrared Spectroscopy and Inductively Coupled Plasma Optical Emission Spectrometry respectively. The infrared spectra showed characteristic bands containing polar functional groups expected confirming that the resin was purely eluted. The elemental concentrations were found to be high compared to other fractions and was confirmed by their T-test values. Zinc had the highest mean concentration of 32.13 ± 35.66 mg/kg, while Mn had the least (1.14 ± 0.17 mg/kg). Results indicated that processing of the crude oil resin may cause catalyst poisoning/fouling, corrosion of equipment/pipelines. Therefore, adequate consideration of these trace metals must be taken before processing.     

Spectroscopic Characterization of Asphaltene Fraction of Nigerian Bitumen

This research article offers data on the spectroscopic elucidation of the asphaltene fraction of Nigerian bitumen in order to establish its features that might aid the developmental processes of the fossil fuel. Bitumen was extracted from the oil sands obtained from six locations where there were oil sand out-crops in Southwestern Nigeria using toluene via Soxhlet extraction and then deasphalted using n-pentane. The organic components of the precipitated asphaltenes were investigated using Fourier transform infrared spectrometry, while the elemental contents were determined using Inductively coupled plasma atomic emission spectroscopy and carbon/nitrogen analyzer. The results revealed that the average content (29.15 wt%) of Nigerian bitumen asphaltenes was less than that of Athabasca (40.10 wt%) but slightly higher than that of Cold Lake bitumen (24.40 wt%). The IR spectra of the asphaltenes indicated the presence of various organics and heteroatoms corroborating that asphaltenes composed of high molecular weight polycyclic constituents comprising of nitrogen, sulfur, and oxygen heteroatoms. The results indicated that the values of Cr, Cu, Fe, Mn, Ni, S, V, and Zn were comparatively higher in the asphaltenes than the parent bitumen due to the presence of comparatively high levels of porphyrins in the asphaltenes than the bitumen, while the concentrations of all the elements were higher in the Nigerian bitumen asphaltene than Nigerian crude oil asphaltene (except S and C). Cross plot analysis result between the asphaltenes and bitumen using their elemental mean concentrations as variables indicates that significant and positive correlation (R² = 0.975) exists between them, indicating very strong interelement and geochemical relationships between them. The elements showed close clustering, indicating similar sources because the elements were known to associate with petroleum hydrocarbon formation. Also, apart from N, S, and C, other elements are transition metals with similar chemical affinity.     

Evaluation of Trace Metals and Physical Properties of Nigerian Crude Oil Saturate Fraction

Analyses of trace elements and physical properties of the saturate fraction of Nigerian crude oil were done in order to establish the characteristics that may aid the developmental processes of the natural resources. Crude oil samples were collected from three different oil fields in Niger-Delta area of Nigeria. The saturate fractions were eluted by column chromatography using n-hexane. The saturate fractions were investigated for functional groups using Fourier transform infrared spectrometry (FT–IR); the elemental concentrations were determined using Atomic absorption spectrometry, while the physical properties (flash point, ash content, refractive index, and color) were determined using standard analytical methods. The results revealed that the infrared spectra of the saturate fraction of the Nigerian crude oil showed mainly the presence of C-H(CH₃) and C-H(CH₂) functional groups, indicating high purity of the samples. The concentrations of the analyzed elements (Mn, Cu, Co, Zn, Fe, V, Cr, and Ni) in the saturate fraction were generally low compared to other fractions of Nigerian crude oil. This study revealed that Co has the highest mean concentration of 1.81 ± 0.36 mg/L, while Mn has the lowest mean concentration of 0.04 ± 0.02 mg/L. The t test values for the comparison of the elemental concentrations of Nigerian crude oil /saturate fraction and crude oil asphaltene/saturate fraction showed significant difference (except Mn) with respect to Nigerian crude oil /saturate fraction. The cluster analysis for the elements showed two groups, which are fairly well correlated indicating similar source and similar chemical affinity. The cross-plot analysis of the Nigerian crude oil and its saturate using elemental concentrations as the variables showed a strong positive inter element correlation since (R² = 0.71), establishing a relationship between the Nigerian crude oil and the saturate fraction. The color of the saturate fraction ranged from off-white to colorless. The results of analysis provide useful information on its conversion mechanism and environmental implications of the development of the fossil fuel deposit.     

The Structural Characterization of Saturate,Aromatic, Resin,and Asphaltene Fractions of Batiraman Crude Oil

Abstract

The structural characterization of fractions of Batiraman crude oil, which is the heavy crude oil from a field in the southeastern part of Turkey, was investigated. Batiraman crude oil and its saturate, aromatic, resin, and asphaltene (SARA) fractions were seperated. Treatment of crude oil with n-heptane provided the separation of asphaltene. Maltene was collected by evaporating the n-heptane from the filtrate. Then, maltene was separeted into saturates, aromatics, and resins by SARA technique. Maltene was separated into saturate, aromatic, and resin fractions using column chromatography. SARA fractions were quantified on a weight percent basis. Fractions of Batiraman crude oil were characterized by elemental analysis, proton nuclear magnetic resonance (¹H NMR) analysis, electrospray ionization mass spectrometry (ESI-MS), and Fourier transform infrared (FTIR) spectroscopy techniques.     

CHEMICAL CHARACTERISTICS OF SUPERCRITICAL TOLUENE EXTRACTS FROM TWO TURKISH LIGNITES

Samples from two major deposits of Turkish lignites were subjected to supercritical toluene extraction at 325°C and 14.1 MPa in an autoclave. The resultant extracts were separated into pre-asphaltene, asphaltene, saturates, aromatics and resin fractions by column chromatography. The fractions were characterized by ¹H-NMR, ¹³C-NMR, IR. and elemental analysis in order to compare the chemical composition of extracis from the two coal samples. The results show that the extracts from the Tungbiiek (T-coal) deposits contain aliphatic constituent which is composed of mostly long chain unbranched alkyl compounds while the extracts from the Soma Mcrkeg (S-coal) deposits contain a significant amount of branched paraffinic compounds. The resin fractions from both samples were found to contain a significant amount of single ring aromatic compounds.     

氯化聚乙烯改性沥青热性能的研究

文章应用四组分分析法、热重分析法（TGA）和示差量热扫描法（DSC）对氯化聚乙烯改性沥青PMB-CPE的热性能进行了研究。结果发现，PMB-CPE中沥青的组分含量发生了变化，饱和分和芳香分减少，胶质和沥青质含量增加；PMB-CPE在起始热分解阶段的失重速率降低，热稳定性提高；PMB-CPE的吸热焓减少，对温度的敏感性降低。     

CHEMICAL CHARACTERISTICS OF SUPERCRITICAL TOLUENE EXTRACTS FROM TWO TURKISH LIGNITES

ABSTRACT

Samples from two major deposits of Turkish lignites were subjected to supercritical toluene extraction at 325°C and 14.1 MPa in an autoclave. The resultant extracts were separated into pre-asphaltene, asphaltene, saturates, aromatics and resin fractions by column chromatography. The fractions were characterized by ¹H-NMR, ¹³C-NMR, IR. and elemental analysis in order to compare the chemical composition of extracis from the two coal samples. The results show that the extracts from the Tungbiiek (T-coal) deposits contain aliphatic constituent which is composed of mostly long chain unbranched alkyl compounds while the extracts from the Soma Mcrkeg (S-coal) deposits contain a significant amount of branched paraffinic compounds. The resin fractions from both samples were found to contain a significant amount of single ring aromatic compounds.     

STRUCTURAL CHARACTERIZATION OF ARABIAN HEAVY CRUDE OIL RESIDUE

ABSTRACT

The residue (370°C+) from Arabian Heavy Crude Oil was separated into four fractions, asphaltenes, resins, aromatcis and saturates. The four fractions were found to be free of artifacts and analytically significant in themselves. Each fraction was further characterized by elemental analysis, infrared spectroscopy, n.m.r. spectroscopy and mass spectroscopy. The aromatics are the major constituent of the residue and the ratio of asphaltenes, resins, aromatics and saturates is about 2:3:8:3. The strucutral characterization study led to the conclusion that asphaltene fraction is maximum hydrogen deficient followed by resins, aromatics and saturates thus suggesting larger degree of ring condensation in the structure of asphaltenes than resins and aromatics.     

THE EFFECT OF ASPHALT COMPOSITION ON THE FORMATION OF ASPHALTENES AND THEIR CONTRIBUTION TO ASPHALT VISCOSITY

ABSTRACT

Interactions among asphalt components have significant effects on the performance of asphalt binder. To understand those interactions, four asphalts, SHRP AAA-I, AAD-I, AAF-I, and AAG-I, were fractionated into three generic fractions according to Corbett's procedure and reblended into asphaltenes/aromatics/saturates ternary mixtures in various ratios. Mixtures were oxidatively aged with atmospheric air at temperatures of 87.7, 93.3, and 98.8°C for 5 to 33 days. The changes in chemical composition and physical properties were monitored using fourier transform infrared spectroscopy (FT-IR) and dynamic mechanical rheometry

The formation of asphaltenes is a major factor in the hardening of asphalt with aging. The data collected in this study indicate that the saturate content in the maltene phase has a profound impact on the contribution that asphaltenes have on the viscosity of aged asphalt. The data also suggest that the aromatics fraction is solely responsible for the formation of asphaltenes as an asphalt oxidizes.     

胜利减压渣油胶质热反应生焦特性的研究

以胜利减压渣油中的饱和分、芳香分和胶质为原料，通过其热反应行为的考察，表明在本反应条件下，饱和分不转化成沥青质和甲苯不溶物；仅有少量芳香分转化成沥青质和甲苯不溶物；在热反应中沥青质和甲苯不溶物的生成主要来自胶质的缩合反应。还比较了饱和分、芳香分和胶质的裂解与缩合性能。研究表明，纯胶质的热反庆体系，其胶溶沥青质的能力很强；原生胶质经热反应后所生成的次生胶质和次生沥青质与减压渣油中的原生胶质和原生沥青     

饱和烃和芳烃的高压液相色谱法精细分离

该文介绍了用高压液相色谱对族组分中的饱和烃、单环芳烃、二环芳烃及三环以上芳烃的精细分离方法。用二级活度的氧化铝除去非烃和沥青质,用正己烷和二氯甲烷依次淋洗出(硅胶)色谱柱上的饱和烃、单环芳烃、二环芳烃及三环以上芳烃。该方法同国外方法相比具有快速、节省试剂的优点,色质谱图显示各组分有较高的分离度。      

THE EFFECT OF ASPHALT COMPOSITION ON THE FORMATION OF ASPHALTENES AND THEIR CONTRIBUTION TO ASPHALT VISCOSITY

Interactions among asphalt components have significant effects on the performance of asphalt binder. To understand those interactions, four asphalts, SHRP AAA-I, AAD-I, AAF-I, and AAG-I, were fractionated into three generic fractions according to Corbett's procedure and reblended into asphaltenes/aromatics/saturates ternary mixtures in various ratios. Mixtures were oxidatively aged with atmospheric air at temperatures of 87.7, 93.3, and 98.8°C for 5 to 33 days. The changes in chemical composition and physical properties were monitored using fourier transform infrared spectroscopy (FT-IR) and dynamic mechanical rheometry

The formation of asphaltenes is a major factor in the hardening of asphalt with aging. The data collected in this study indicate that the saturate content in the maltene phase has a profound impact on the contribution that asphaltenes have on the viscosity of aged asphalt. The data also suggest that the aromatics fraction is solely responsible for the formation of asphaltenes as an asphalt oxidizes.     

常压渣油组分的电导率

 研究了常压渣油组分在苯溶液中的电导率。采用液相色谱法将大港、中东、塔河常压渣油各分成6个组分,测定了各组分苯溶液的电导率,并从各组分的平均相对分子质量、介电常数等数据计算了它们的平均偶极矩。采用极限质量分数电导率比较了大港、中东、塔河常压渣油各组分的导电能力和渣油体系的胶体稳定性。结果表明,各组分苯溶液的电导率随着组分质量分数的增大而增大,两者呈线性关系。3种渣油各组分的极限质量分数电导率均按以下顺序依次减小：沥青质、重胶质、中胶质、轻胶质、重芳烃、轻芳烃和饱和分;平均偶极矩也按该顺序依次下降,与极限质量分数电导率下降趋势相同,但下降幅度不同;大港常压渣油沥青质组分的平均偶极矩远小于中东和塔河常压渣油的,但极限质量分数电导率却大于它们的。3种渣油中,大港常压渣油的胶体稳定性最好。     

ASPHALTENE PRECIPITATION FROM COLD LAKE AND ATHABASCA BITUMENS

The onset of asphaitene precipitation from Cold Lake and Athabasca bitumens was studied using a heat transfer technique. The onset for these two types of bitumen was at a n-heptane to bitumen volume ratio of 1.4 to 1.7. Since it is important to suppress the onset of precipitation, a number of additives (aromatics; hydrogen donor solvents, solvents with the heteroatoms nitrogen, sulphur, and oxygen; and surfactants) were tested for their ability to delay the onset of asphaitene precipitation from Cold Lake bitumen. Phenanthrene, an aromatic, and the surfactant nonyl-phenol were found to be most effective. Cold Lake bitumen maltenes were found to be as effective as the aromatic chemical additives in delaying the onset of asphaitene precipitation. As the maltenes fraction contains saturates, the resins fraction alone should be even more effective at delaying precipitation.     

Analysis of the thermal hydrocracking of heavy fuel oil

The thermal hydrocracking of Mexican heavy fuel oil was studied at 1200 psia and different reaction temperatures (370, 380, 390 and 400°C). The results show that the vacuum residue which constitutes 62 wt. % of the heavy fuel oil and contains 47 wt. % resins and 23.3 wt. % asphaltenes, reacts to form lighter hydrocarbons (IBP-540°C), solid and gas. Resins transform more easily to saturates, and gases are produced mainly from the asphaltene fraction, indicating that the terminal alkyl groups in this fraction are shorter than those present in the resin fraction. The C-C scission reactions dominate the transformation of heavy fuel oil in the interval from 370 to 390°C, whereas the carbon rejection reactions are dominant at 400°C. Finally, the thermal hydrocracking of heavy fuel oil at 390°C appears suitable since at this temperature the reaction produces the greater amount of atmospheric distillates (+20.5 wt. %) and a low content of solid (2.0 wt. %) and gas (2.1 wt. %).     

STRUCTURAL CHARACTERIZATION OF ARABIAN HEAVY CRUDE OIL RESIDUE

The residue (370°C+) from Arabian Heavy Crude Oil was separated into four fractions, asphaltenes, resins, aromatcis and saturates. The four fractions were found to be free of artifacts and analytically significant in themselves. Each fraction was further characterized by elemental analysis, infrared spectroscopy, n.m.r. spectroscopy and mass spectroscopy. The aromatics are the major constituent of the residue and the ratio of asphaltenes, resins, aromatics and saturates is about 2:3:8:3. The strucutral characterization study led to the conclusion that asphaltene fraction is maximum hydrogen deficient followed by resins, aromatics and saturates thus suggesting larger degree of ring condensation in the structure of asphaltenes than resins and aromatics.     

STRUCTURAL FEATURES OF ATHABASCA BITUMEN RELATED TO UPGRADING PERFORMANCE

ABSTRACT

Using a combination of instrumental and chemical methods many new classes of compounds appearing as homologous series have been detected in Athabasca oil sand bitumen and in the chemical and thermal degradative products of asphaltene and the heavy ends of maltene. In general, the volatile portion of the maltene is rich in cyclic terpenoid structures and devoid in aliphatic compounds or normal alkane-derived cyclic molecules while the asphaltene fraction and heavy ends of maltene are abundant in normal alkyl-substituted aromatics, thianes, thiolanes, thiophenes, benzo- and dibenzothiophenes

Ru(VM)-catalyzed oxidation permitted the quantitative estimation of the n-alkyl groups attached to aromatic carbons and of n-alkyl bridges between two aromatic units and their concentration distribution according to chain length. It also showed the presence of a large naphthenic core containing cyclic sulfides, which, during oxidation, were converted to their sulfones.     

EFFECT OF INTER-MOLECULAR ASSOCIATION ON BITUMEN OXIDATION

ABSTRACT

The hypothesis that inter-molecular associations between species in petroleum bitumens affects the rate of air oxidation of the bitumens was examined using infrared spectroscopy, gel permeation chromatography and viscosity measurements. Experiments were carried out in which the rate of oxidation of two different bitumens and their fractions (maltenes, resins, asphaltenes) were measured in terms of carbonyl group formation. In THF solution at 30°C the rates of reaction of the maltene and asphaltene fractions were the same when oxidised separately or as a mixture. Although the presence of inter-molecular associations were confirmed by gel permeation chromatography, the results indicated that such effects were unimportant to the rate of the reaction. Further experiments were performed in which neat bitumen, resin and maltene (n-heptane) factors and reconstituted mixtures were oxidised under 2069 kPa of oxygen or air at 40°C or 60°C. Again, no evidence for the effect of inter-molecular association on oxidation rate was obtained. Another experiment in which a bitumen, rejuvenating oil (RO), and a mixture of the two was oxidised (2069 kPa air, 60°C) again showed that the reaction rate of the bitumen and RO were the same when oxidised separately or in the mixture. However, in contrast, the rate of increase of viscosity of the bitumen was significantly affected by the RO and was attributed to dispersal of polar oxidation products by the RO.     

原油及族组分生成动力

利用黄金管-高压釜限定体系,对采自东营凹陷牛15井（沙三下亚段）和王120井（沙四上亚段）的烃源岩所制备的干酪根样品在50 MPa的恒定压力下,以2℃/h和20℃/h的升温速率分别进行程序升温热解,热解后的产物通过索氏抽提后经微型柱色谱分离为饱和烃、芳烃、非烃和沥青质。借助Kinetics2000软件获取总烃及族组分的生成动力学参数,结合东营凹陷南坡新生代烃源岩的埋藏史和热史,开展了原油及族组分生成动力学研究。结果表明,东营凹陷沙三下亚段和沙四上亚段烃源岩进入生烃门限的地质时间分别为4.26 × 106 a 和 24.85 × 106 a,沙三下亚段烃源岩目前处于主要生油阶段,而沙四下亚段烃源岩处于生油的后期阶段。现阶段,东营凹陷沙三下亚段烃源岩生成的饱和烃、芳烃、非烃和沥青质的累计产率分别为222.03 mg/g,71.30 mg/g,62.37 mg/g和 50.04 mg/g;而沙四上亚段烃源岩生成的饱和烃、芳烃、非烃和沥青质的累计产率分别为282.94 mg/g,98.98 mg/g,66.79 mg/g和 53.82 mg/g     

可逆性吸脱附材料用于气相色谱法测定喷气燃料中芳烃含量

为提高喷气燃料中芳烃含量测定的准确性、精密度和分析速率,解决荧光指示剂吸附法面临的荧光指示剂供应问题,提出采用气相色谱(GC)快速测定喷气燃料中芳烃总量的方法。通过制备芳烃可逆性吸脱附材料,并将其用于气相色谱柱固定相,实现了喷气燃料中饱和烃与芳烃的气相色谱分离。该气相色谱法的芳烃测定结果与芳烃配制结果相关系数达到0.9999,加标回收率100%±5%,定量结果准确,重复性标准偏差为0.21%,重复性良好。为确定该气相色谱方法的准确性和可靠性,测定了加氢裂化和直馏两种工艺来源的喷气燃料样品,讨论了喷气燃料饱和烃和芳烃相对密度对喷气燃料中芳烃质量分数和体积分数换算结果的影响,并与GB/T 11132—2008荧光指示剂吸附法(FIA法)和NB/SH/T 0939—2016示差折光检测器高效液相色谱法(HPLC)的测定结果进行了比较,分析结果具有较好的一致性。此外,采用核磁共振(NMR)分析方法对加氢裂化和直馏两种工艺来源的喷气燃料样品中可能存在的烯烃进行了鉴别,结果表明,加氢裂化和直馏两种工艺来源的喷气燃料样品中烯烃最大质量分数不超过1%,不会对芳烃含量的测定产生较大的影响。