Composition Of Bitumen Research Articles

Evaluating Re–Os systematics in organic-rich sedimentary rocks in response to petroleum generation using hydrous pyrolysis experiments

Successful application of the 187Re–187Os geochronometer has enabled the determination of accurate and precise depositional ages for organic-rich sedimentary rocks (ORS) as well as establishing timing constraints of petroleum generation. However, we do not fully understand the systematics and transfer behaviour of Re and Os between ORS and petroleum products (e.g., bitumen and oil). To more fully understand the behaviour of Re–Os systematics in both source rocks and petroleum products we apply hydrous pyrolysis to two immature hydrocarbon source rocks: the Permian Phosphoria Formation (TOC=17.4%; Type II-S kerogen) and the Jurassic Staffin Formation (TOC=2.5%; Type III kerogen). The laboratory-based hydrous pyrolysis experiments were carried out for 72h at 250, 300, 325 and 350°C. These experiments provided us with whole rock, extracted rock and bitumen and in some cases expelled oil and asphaltene for evaluation of Re–Os isotopic and elemental abundance.The data from these experiments demonstrate that the majority (>95%) of Re and Os are housed within extracted rock and that thermal maturation does not result in significant transfer of Re or Os from the extracted rock into organic phases. Based on existing thermodynamic data our findings suggest that organic chelating sites have a greater affinity for the quadravalent states of Re and Os than sulphides.Across the temperature range of the hydrous pyrolysis experiments both whole rock and extracted rock 187Re/188Os ratios show small variations (3.3% and 4.7%, for Staffin, respectively and 6.3% and 4.9% for Phosphoria, respectively). Similarly, the 187Os/188Os ratios show only minor variations for the Staffin and Phosphoria whole rock and extracted rock samples (0.6% and 1.4% and 1.3% and 2.2%). These isotopic data strongly suggest that crude oil generation through hydrous pyrolysis experiments does not disturb the Re–Os systematics in ORS as supported by various studies on natural systems.The elemental abundance data reveal limited transfer of Re and Os into the bitumen from a Type III kerogen in comparison to Type II-S kerogen (0.02% vs. 3.7%), suggesting that these metals are very tightly bound in Type III kerogen structure. The 187Os/188Os data from the pyrolysis generated Phosphoria bitumens display minor variation (4%) across the experimental temperatures, with values similar to that of the source rock. This indicates that the isotopic composition of the bitumen reflects the isotopic composition of the source rock at the time of petroleum generation. These data further support the premise that the Os isotopic composition of oils and bitumens can be used to fingerprint petroleum deposits to specific source rocks.Oil generated through the hydrous pyrolysis experiments does not contain appreciable quantities of Re or Os (∼120 and ∼3ppt, respectively), in contrast to natural oils (2–50ppb and 34–288ppt for Re and Os, respectively), which may suggest that kinetic parameters are fundamental to the transfer of Re and Os from source rocks to oils. From this we hypothesise that, at the temperatures employed in hydrous pyrolysis, Re and Os are assimilated into the extracted rock as a result of cross-linking reactions.

Syntheses of Alkylated Aromatic Model Compounds To Facilitate Mass Spectral Characterization of Heavy Oils, Resids, and Bitumens

This study summarizes the synthesis of model compounds. Long-chain alkyl multi-ring heteroaromatics are the synthetic targets. These compounds are considered analogues of similar compounds that are present at abundant levels in petroleum crude oils, resids, heavy oils, deasphalted oils, asphaltenes, and bitumens, and they are responsible for coke formation and other processing problems. Model compounds are not readily available. Some models have been synthesized to approximate the physical and chemical behavior of real asphaltenes, but the structures are not completely consistent with the current structural understanding. The composition of petroleum crudes, resids, heavy oils, and bitumens has been a subject of intense research for years. The structure of these coke-forming molecules is generally thought to be an aromatic core of critical molecular weight and number of fused aromatic rings. This critical ring number is around 4–5 fused aromatic rings, which bear alkyl side chains and heteroatoms. This general structural view is still being improved. During coking, these side chains thermally cleave off of the aromatic core and leave the coker as volatile liquids and gas. The aromatic cores are thermally stable, and they are not volatile. They remain in the coker until they condense and form low-value coke. The purpose of this research was to synthesize model compounds representing the molecular structure of the coke-forming molecules. These compounds will be used to model the behavior of resids, heavy oils, and bitumens to understand their processing chemistry and their physical and chemical properties. Model compounds that reasonably represent the structural data with boiling point ranges that map directly onto the boiling point ranges of real heavy oils, resids, and bitumens have been successfully synthesized. Important structural features are emphasized in these models, such as high molecular weight [∼1000 atomic mass units (amu)] with multi-ring aromatic cores, long alkyl side chains, and the inclusion of sulfur and nitrogen. These model compounds can be used to calibrate analytical methods to provide response factors for quantitative characterization of alkylated aromatics in real petroleum fractions and to better understand thermal chemistry kinetics.

Influence of the morphology of thermoplastic elastomers on the properties of bitumen composites

Bitumen properties may be successfully modified if the polymeric modifiers have the ability to control the elastic and plastic properties within wide temperature ranges of −30/−40°C to +45/+60°C. The article presents a study on the ability of two thermoplastic elastomers, thermoplastic block co-polymer styrene–styrene butadiene (SBS) and the co-polymer ethylene–vinyl acetate (EVA), to be used in obtaining polymer bitumen composites with controlled properties. The elastic and plastic properties of the bitumen composites can be more easily controlled if these composites are modified with SBS. This thermoplastic elastomer is characterized by an optimum ratio between soft domains of amorphous polybutadiene and rigid ones of those represented by the thermoplastic blocks of polystyrene.

Micron Fly Ash/SBS Modified Bitumen: Preparation and Aging Property

Abstract. Micron fly ash/SBS modified bitumen composites were prepared by melt intercalation. The physical properties and ageing properties of micron fly ash/SBS modified bitumen were investigated. The results showed that micron fly ash/SBS modified bitumen exhibited a decreasing penetration, an increasing softening point, and a decreasing ductility. Compared with that of SBS modified bitumen, the anti-aging property of the micron fly ash/SBS modified bitumen becomes worse.

Bitumen Production via Tar Oxidation in the Presence of Petroleum Resin with Fluorine-Containing Groups

The tar oxidation process has been studied at 523 K, air flow rate of 2.0; 2.5 and 5.0 h-1 and process time of 6, 9 and 12 h in the presence of 2.5; 5.0 and 7.5 mas % (to calculate for the raw material)of petroleum resin with fluorine atoms. The tar is the residue of black oil vacuum distillation obtained from the oils of Western-Ukrainian fields. The effect of process conditions on the characteristics of obtained bitumen has been determined. The structural-group composition of blown bitumen has been examined.

Preparation and Properties of OMMT/ SBS Modified Bitumen

Organophilic montmorillonite (OMMT)/SBS modified bitumen composites were prepared by melt intercalation. The physical properties and ageing properties of OMMT/SBS modified bitumen were investigated. The results showed that OMMT/SBS modified bitumen exhibited a decreasing penetration, an increasing softening point, and a decreasing ductility. Compared with that of SBS modified bitumen, the OMMT /SBS modified bitumen can enhance the aging resistance of SBS modified bitumen.

Toward Identification of Molecules in Ill-Defined Hydrocarbons Using Infrared, Raman, and Nuclear Magnetic Resonance (NMR) Spectroscopy

The molecular composition of heavy oil and bitumen is critical for process design calculations and for the selection of production and refining processes, reaction schemes, and conditions that optimize their economic value. These materials remain ill-defined on a molecular basis. For example, diverse molecular structures have been proposed for asphaltenes on the basis of the same physical samples and analytical data [1H and 13C nuclear magnetic resonance (NMR) spectroscopy, mass spectroscopy, and elemental composition]. Molecule construction algorithms appear under constrained by these analytical data, particularly at the molecular subunit length scale (e.g., naphthenic and aromatic groups and aliphatic chains) from both an identification and a mass balance perspective. In this work, we address whether spectral data can provide additional constraints at this length scale that reduces the ambiguity of outcomes from molecule construction algorithms, by making use of spectral data for possible subunits. In this proof of concept investigation, infrared (IR), Raman, and 1H and 13C NMR spectra were computed using density functional theory (DFT) and the B3LYP/6-311G basis set. The molecular subunits present in more than 20 large molecules were probed by spectral subtraction based on spectral contributions from a library of small molecules, because it is at this length scale that the greatest uncertainty in molecule identification and construction algorithms appears to arise. Spectral subtraction using 1H NMR spectroscopy failed to identify molecular subunits in any of the more than 20 large molecules evaluated. 13C NMR spectroscopy identified only 3 large molecules. In contrast, joint use of IR and Raman spectroscopy identified more than 75% of the aromatic subunits present, and naphthenic and aromatic subunits were discriminated. Aliphatic chain length remained poorly defined, and the resulting molecule compositions are qualitative. It is expected that the results of this work will inform molecule construction and identification algorithms for ill-defined hydrocarbons.

Utylizacja odpadow polistyrenu spienionego w kompozycjach z wtornymi bitumami naftowymi

The conditions of preparations of homogeneous and stable compositions of secondary petroleum bitumens (Table 1, 2) with addition of expanded polystyrene (EPS) waste (Table 3) were elaborated. The following physicochemical properties of the bitumen/polymer compositions obtained were evaluated: thermal stability, melting point and dropping point (Fig. 1, 2), penetration (Fig. 3), ductility (Fig. 4), hardness and elastic reverse (Table 4). The penetration index (PI), being a measure of thermal susceptibility of petroleum asphalt, was calculated on the basis of results of penetration as a function of temperature. The compositions meeting the basic requirements for brittle industrial asphalts and hard road ones were selected from the systems prepared.

Chemical and Thermal Characterization of Road Bitumen Ageing

Bitumen ageing stands for a number of physico-chemical modifications that occur in bitumen as a response to environmental conditions. Several tests have been proposed to simulate bitumen ageing. Two of the most common ones are: a) the Rolling Thin Film Oven Test (RTFOT), which simulates short term ageing; b) the Pressure Ageing Vessel (PAV) test, which accounts for long-term ageing and it is usually performed on the RTFOT residue. A study of the physico-chemical modifications of a 50/70 pavement grade bitumen caused by ageing is presented. Both RTFOT and PAV tests were used. A follow-up of bitumen modifications due to ageing was done by several methods. In particular: 1) Fourier transform infrared spectroscopy (FTIR), to follow bitumen oxidation by the increase of oxygenated functional groups, which were quantified by taking appropriate structural indices; 2) Iatroscan thin layer chromatography (TLC), to follow bitumen composition expressed by the generic SARA fractions (saturates, aromatics, resins and asphaltenes); 3) Gel permeation chromatography (GPC), under “ultra-fast” conditions, to follow the colloidal structure of bitumen; and 4) Differential scanning calorimetry (DSC), to evaluate the changes of the crystallized fractions (%FC) and the glass relaxation temperature (Tg). The results show that the PAV test causes more severe changes in bitumen than the RTFOT test. In particular, the evolution of the oxidation processes could be quantified by taking carbonyl and sulfoxide structural indices. Ageing also modified the SARA profile, namely, the relative contribution of aromatics, resins and asphaltenes fractions. On the other hand, DSC data remained almost unaffected after ageing tests, which may be indicative of the survival of most of the phases of the bitumen after these tests. Finally, a comparative analysis of the sensitivity and performance of all these methods is presented.

Prediction of mechanical properties of polypropylene/waste ground rubber tire powder treated by bitumen composites via uniform design and artificial neural networks

Polypropylene (PP)/waste ground rubber tire powder (WGRT) composites were studied with respect to the effect of bitumen and maleic anhydride-grafted styrene–ethylene–butylene–styrene (SEBS-g-MA) content by using the design of experiments (DOE) approach, whereby the effect of the four polymers content on the final mechanical properties were predicted. Uniform design method was especially adopted for its advantages. Optimization was done using hybrid artificial neural network–genetic algorithm (ANN–GA) technique. The results indicated that the composites showed fairly good ductibility provided that it had a relatively higher concentration of bitumen and SEBS-g-MA under the studied condition. A quantitative relationship was presented between the material concentration and the mechanical properties as a set of contour plots, which were confirmed experimentally by testing the optimum ratio.

Changes in the Chemical Composition of Australian Bitumens

The purpose of this paper is to discuss changes in the chemical composition of Australian bitumens while utilizing the Gaestel Index. The analysis technique should be useful for assessing future Australian and overseas bitumens in terms of possible field problems, for determining the cause of field problems, and for developing solutions to these. Colloidally unstable and temperature susceptible bitumens had high Gaestel values while tender bitumens had a low Gaestel Index. Multigrade bitumens had a much higher Gaestel Index than other bitumens but have not shown colloidal instability in service due, in part, to the different nature of their asphaltenes. This indicates that a number of factors must be taken into account when interpreting compositional data. Chemical specification of bitumens is probably impractical at present. A bitumen fractionation procedure was developed based on the Iatroscan device. Asphaltenes are precipitated conventionally then maltenes are separated using Iatroscan thin layer chromatography and the proportions of each maltenes fraction measured using a flame ionisation detector. The procedure is comparatively rapid, and control bitumen is included in every run to improve reproducibility.

Molecular and isotopic compositions of bitumens in Silurian tar sands from the Tarim Basin, NW China: Characterizing biodegradation and hydrocarbon charging in an old composite basin

Biodegradation and oil mixing in Silurian sandstone reservoirs of the Tarim Basin, one of the largest composite basins in China, were investigated by analyzing the molecular characteristics and stable carbon isotopic signatures of low-molecular-weight (LMW) saturated hydrocarbons and high-molecular-weight (HMW) asphaltenes. Detection of 25-norhopanes and 17-nortricyclic terpanes in most Silurian tar sands from the Tabei Uplift in the Tarim Basin suggests a much greater degree of biodegradation here than in the Tazhong Uplift. This explains the relatively more abundant tricyclic terpanes, gammacerane, pregnane and diasteranes in tar sands from the Tabei Uplift than in those from the Tazhong Uplift. Hence, care must be taken when assigning oil source correlations using biomarkers in tar sands because of the biodegradation and mixing of oils derived from multiple sources in such an old composite basin. Asphaltenes in the tar sands seem to be part of the oil charge before biodegradation, depending on the relative anti-biodegradation characteristics of asphaltenes, the similarity in carbon isotopic signatures for asphaltenes and their pyrolysates, and the consistent product distribution for flash pyrolysis and for regular steranes in asphaltene pyrolysates, regardless of whether the tar sands were charged with fresh oil. According to the relative distributions of regular steranes and the relatively abundant 1,2,3,4-tetramethylbenzene significantly enriched in 13C, the oil sources for asphaltenes in the tar sands might be related to lower Paleozoic marine source rocks formed in euxinic conditions. Nevertheless, the relatively low abundance of gammacerane and C 28 regular steranes observed in asphaltene pyrolysates and residual hydrocarbons, within limited samples investigated in this work, made a direct correlation of oils originally charged into Silurian tar sands with those Cambrian source rocks, reported so far, seem not to be possible. Comparison of carbon isotopic signatures of n-alkanes in asphaltene pyrolysates with those of LMW saturated hydrocarbons is helpful in determining if the abundant n-alkanes in tar sands are derived from fresh oil charges after biodegradation. The limited carbon isotopic data for n-alkanes in LMW saturated hydrocarbons from the tar sands can be used to classify oils charged after biodegradation in the composite basin into four distinct groups.

Synthesis and Evaluation of Modified Polyethylene Wax Applied as Dispersant in Rubber Bitumen Composites

Grain rubber obtained from waste tyre has become one of the most important bitumen modifiers nowadays, but rubber precipitation from bitumen can cause problems during utilization. In our experimental work additives were synthesised as dispersant for rubber bitumen composites. Raw material was polyethylene wax (PEW) obtained from mild thermal cracking of polyethylene waste. The synthesis was a copolymerisation of olefins and maleic-anhydride. During the products evaluation the main analytical method was Fourier transform infra-red (FT-IR) spectroscopy. There were significant differences between the characteristic of raw material and synthesised products. The dispersant effect of the additives was studied in rubber-bitumen composites. All additives increased the stability of rubber-bitumen composites. From the results of the experiments it was stated that the modified polyethylene wax obtained from polyethylene waste can solve the instability problem of rubber-bitumen composites.

Composition of bitumens from alkylated peat

The composition of bitumen compounds from alkylated peat was determined. An increase in the yield of bitumen from alkylated peat is based on the esterification reaction. Various compounds from peat can serve as alternative raw materials for chemical industry.

Changes in the Chemical Composition of Australian Bitumens

ABSTRACT A bitumen fractionation procedure was developed based on the Iatroscan device. Asphaltenes are precipitated conventionally then maltenes are separated using Iatroscan thin layer chromatography and the proportions of each maltenes fraction measured using a flame ionisation detector. The procedure is comparatively rapid, and a control bitumen is included in every run to improve reproducibility. Testing of bitumens from the ARRB library covering the half century from 1956 to 2004 indicated that there had been a change in chemical composition over the period. Field performance problems were associated with low asphaltenes content or high saturates content. A single parameter, the Gaestel Index, indicated regions of poor performance. Colloidally unstable and temperature susceptible bitumens had high Gaestel values while tender bitumens had a low Gaestel Index. The analysis technique should be useful for assessing future Australian and overseas bitumens in terms of possible field problems, for determining the cause of field problems, and for developing solutions to these. Chemical specification of bitumens is probably impractical at present.

Kerogen pyrolysis in the presence and absence of water and minerals: Amounts and compositions of bitumen and liquid hydrocarbons

The confined pyrolysis experiments of Kukersite kerogen in the presence and absence of minerals and water revealed the effects of mineral acidity and water/OC ratio on the conversion of kerogen into petroleum. The amount of bitumen and liquid hydrocarbons demonstrate that organic maturation rate increase with mineral acidity even in the presence of a large amount of water (water/OC 7–10). Organic maturation rate appeared unaffected with the addition of a small amount of water (water/OC 1.5), but it can be retarded with the addition of a large amount of water (water/OC 7–10) in confined pyrolysis experiments. The relative abundances of n-alkanes decrease whereas those of isoalkanes, cycloalkanes and light alkylbenzenes increase with both the mineral acidity and water/OC ratio. The relative abundances of naphalene, methylnaphalenes, phenanthrene and methylphenanthrenes also increase with mineral acidity but exhibit no clear variation trend with water/OC ratio.

Characterization of the properties of thermoplastic elastomers containing waste rubber tire powder

The aim of this research was to recycle waste rubber tires by using powdering technology and treating the waste rubber tire powder with bitumen. It has been proven that the elongation at break, thermal stability and processing flowability of composites of polypropylene (PP), waste rubber tire powder (WRT) and bitumen composites are better than those of PP/WRT composite. A comparative study has been made to evaluate the influence of bitumen content and different compatibilizers on the properties of PP/WRT/bitumen composites, using a universal testing machine (UTM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and a capillary rheometer. The results suggested that the properties of PP/WRT/bitumen composites were dependent on the bitumen content and the kind of compatibilizer used.

Scanning Electron Microscopy Method as a Tool for the Evaluation of Selected Materials Microstructure

This paper introduces CDV's research on microstructure evaluation of two selected materials used in pavements or structures, i.e. cement concrete and bitumen. A Scanning Electron Microscope (SEM) has been used as the main equipment. In the case of cement concrete time-dependent changes in the microstructure of self-compacting concrete (SSC) are described. The microstructures and differences in void and pore system of matured SSC with commonly used micro-fillers are also shown here. In the case of bitumen the paper anticipates that the relationship between the composition, structure and usable properties of bitumen have not yet been clarified enough. The SEM method requires an appropriate preparation as the raw bitumen samples can not be watched directly. The oil fraction, precluding the observation, must be eliminated. Nevertheless, its removal may cause a modification of the original structure, and this might consequently have an impact on the results of the observation.

40 加速酸化試験におけるアスファルトビチューメンの組成変化(重質油(1))

40 加速酸化試験におけるアスファルトビチューメンの組成変化(重質油(1))

Effect of montmorillonite on properties of styrene–butadiene–styrene copolymer modified bitumen

AbstractClay/styrene–butadiene–styrene (SBS) modified bitumen composites were prepared by melt blending with different contents of sodium montmorillonite (Na‐MMT) and organophilic montmorillonite (OMMT). The structures of clay/SBS modified bitumen composites were characterized by XRD. The XRD results showed that Na‐MMT/SBS modified bitumen composites may form an intercalated structure, whereas the OMMT/SBS modified bitumen composites may form an exfoliated structure. Effects of MMT on physical properties, dynamic rheological behaviors, and aging properties of SBS modified bitumen were investigated. The addition of Na‐MMT and OMMT increases both the softening point and viscosity of SBS modified bitumens and the clay/SBS modified bitumens exhibited higher complex modulus, lower phase angle. The high‐temperature storage stability can also be improved by clay with a proper amount added. Furthermore, clay/SBS modified bitumen composites showed better resistance to aging than SBS modified bitumen, which was ascribed to barrier of the intercalated or exfoliated structure to oxygen, reducing efficiently the oxidation of bitumen, and the degradation of SBS. POLYM. ENG. SCI., 47:1289–1295, 2007. © 2007 Society of Plastics Engineers