Maltene Fractions Research Articles

Discriminating Brazilian crude oils using comprehensive two-dimensional gas chromatography–mass spectrometry and multiway principal component analysis

The geochemical characterization of petroleum is an essential task to develop new strategies and technologies when analyzing the commercial potential of crude oils for exploitation. Due to the chemical complexity of these samples, the use of modern analytical techniques along with multivariate exploratory data analysis approaches is an interesting strategy to extract relevant geochemical characteristics about the oils. In this work, important geochemical information obtained from crude oils from different production basins were obtained analyzing the maltene fraction of the oils by comprehensive two-dimensional gas chromatography coupled to quadrupole mass spectrometry (GC×GC–QMS), and performing multiway principal component analysis (MPCA) of the chromatographic data. The results showed that four MPC explained 93.57% of the data variance, expressing mainly the differences on the profiles of the saturated hydrocarbon fraction of the oils (C13-C18 and C19-C30n-alkanes and the pristane/phytane ratio). The MPC1 grouped the samples severely biodegraded oils, while the type of the depositional paleoenvironments of the oils and its oxidation conditions (as well as their thermal maturity) could be inferred analysing others relevant MPC. Additionally, considerations about the source of the oil samples was also possible based on the overall distribution of relevant biomarkers such as the phenanthrene derivatives, tri-, tetra- and pentacyclic terpanes.

Spectroscopic characterization of the maltene fraction of Nigerian bitumen for potential health-risk assessment

ABSTRACT This study was carried out on maltene fraction of Nigerian bitumen to infer the environmental and health implications of its uses and also to characterize the fossil fuel. Bitumen was extracted from the oil sands obtained from six locations in Southwestern Nigeria using toluene via Soxhlet extraction and then deasphalted using n-pentane. The organic components of the maltenes were investigated using Fourier transform infrared spectroscopy, while the elemental content was determined using inductively coupled plasma-optical emission spectrometry (ICP-OES) and the radioactivity levels were measured using a sodium iodide (NaI)-based Gamma Spectrometry Detector System. The IR spectra of the maltene indicated the presence of various organics and heteroatoms, corroborating the fact that maltene is composed of high molecular weight polycyclic constituents comprising nitrogen, sulfur, and oxygen heteroatoms. The result of the elemental concentrations revealed that sulfur with the mean value of 2.155 μg/g comparatively has the highest concentration in the samples, followed by Fe (1.25μg/g), while Mn has the least value (0.075) μg/g. The values of the analyzed elements were comparatively lower in the maltene fraction than in the bitumen and higher molecular weight fractions of Nigerian bitumen, but higher than the maltene fraction of Nigerian crude oil (except Cr and Ni). The result of the cross-plot analysis between maltene and bitumen using their elemental mean concentrations as variables indicated significant strong and positive correlation (R2 = 0.81) between them, indicating very strong inter-element and geochemical relationships between them. The elements showed close clustering, indicating similar sources or similar chemical affinity. The average activity concentrations of 238U, 232Th, and 40K determined with a view to ascertaining the radiological health consequences associated with the burning of this maltene fraction were 1.66 ± 1.07, 0.72 ± 0.49, and 15.93 ± 3.37 Bqkg−1, respectively. These values are below the standard values in radiation protection. The radiological health consequences associated with the burning of maltene fraction of Nigerian bitumen were insignificant with no radiological hazard to the general public, but long exposure may pose an intrinsic health hazard.

Impact of Laboratory-Induced Thermal Maturity on Asphaltene Molecular Structure

The structure of asphaltenes of various maturities prepared by semiopen pyrolysis of Green River Shale is measured by elemental analysis, laser desorption laser ionization mass spectrometry (L2MS), surface assisted laser desorption ionization (SALDI) mass spectrometry, sulfur X-ray absorption near edge structure (XANES) spectroscopy, and infrared (IR) spectroscopy. These measurements demonstrate systematic changes in the composition of asphaltenes during thermal maturation. At low maturities, the evolution of asphaltene composition is dominated by changes in the heteroatoms: total sulfur as well as carbon–oxygen, sulfur–oxygen (sulfoxide), and aliphatic carbon–sulfur (sulfide) bonds are lost, while the molecular weight increases. At high maturities, the sulfur content and speciation as well as molecular weight are relatively constant while the evolution in composition is dominated by changes in the carbon backbone: the abundance of aromatic relative to aliphatic carbon increases, the length of aliphatic chains shortens, and the abundance of aromatic C–H bonds increases greatly. The distribution of different carbon–oxygen functional groups is relatively unchanged over the entire maturity range. These changes sometimes mirror and sometimes oppose compositional changes in the bitumen, suggesting that the composition of the asphaltene and maltene fractions of bitumen evolve differently. The observed changes in asphaltene structure are not fully independent of one another, as the composition of asphaltenes is constrained to maintain a balance of the strength of intermolecular forces to ensure solubility in aromatic solvent and insolubility in aliphatic solvent (the definition of asphaltenes). That constraint leads to a decrease in sulfoxide content (weakening intermolecular forces by reducing dipole interactions) concurrent with an increase in molecular weight (strengthening intermolecular forces). These trends in asphaltene composition with maturity are expected to occur in naturally occurring source rocks, such as some tight-oil formations, but not necessarily in conventional reservoir rocks where the asphaltenes escape from the source rock and enter the reservoir during maturation.

Correlation among Petroleomics Data Obtained with High-Resolution Mass Spectrometry and Elemental and NMR Analyses of Maltene Fractions of Atmospheric Pressure Residues

In this study, maltenes of atmospheric pressure residue oils were fractionated into five fractions and the fractions were examined by elemental analysis, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), and 1H nuclear magnetic resonance (NMR) spectroscopy. The obtained data were compared to examine the correlations among the data. The correlation coefficients (R2) were 0.88 and 0.89 respectively between the N and S contents determined by elemental analysis and summed relative abundances of N and S containing compounds observed by FT-ICR MS. Especially, correlation between S content and summed relative abundances of S containing compounds was observed. Further, correlation between %1Hnon-aro determined from NMR data and %Cnon-aro obtained from FT-ICR MS data was observed. %1Hnon-aro was calculated from the relative summed area of peaks in the non-aromatic region (0.5–4.5 ppm) of the NMR spectra. %Cnon-aro values were calculated from double bond equivalence values by assuming linear ...

Adsorption efficiency of poly(ethylene glycol)/chitosan/CNT blends for maltene fraction separation.

Poly(ethylene glycol)/chitosan (PEG/CH) hydrogel and its composite containing carbon nanotubes (PEG/CH/CNTs) were prepared using a simple blending method. The effect of the PEG/CH ratio on the water uptake was studied and optimized. And the prepared hydrogels were characterized by XRD, SEM, and FTIR. Also, the ability of each of the prepared hydrogels to adsorb and separate maltene fractions was compared using saturates, aromatics, resins, and asphaltenes (SARA) method. From the results, it was noticed that the adsorption capacity and separation ability of PEG/CH/CNT are better than that of PEG/CH. But the released amount of alkane fractions using these hydrogels is higher than that in the reference (without using hydrogel). This may be attributed to degradation of maltene residue to alkanes and that degradation is better by using PEG/CH adsorbent than PEG/CH/CNT. Although, from a practical point of view, where PEG/CH/CNT hydrogel may be favorable, it has an acceptable ability to adsorb and separate the maltene fractions.

Re–Os dating of maltenes and asphaltenes within single samples of crude oil

Re–Os geochronology of oil may constrain the timing of oil formation and improve oil-source and oil–oil correlations. Typically, asphaltene (ASPH), the heaviest and most Re–Os rich oil fraction, from multiple oils within an oil field or a larger petroleum system are analyzed to obtain sufficient spread in Re–Os isotopic ratios, a mathematical necessity for precise Re–Os isochrons.Here we offer a new approach for Re–Os geochronology of oil based on isotopic analyses of different fractions within a single sample of crude oil. We studied three oils from the Gela oil field, southern Sicily, Italy, recovered from Triassic–Jurassic stratigraphic intervals (Streppenosa, Noto, and Sciacca Formations) within the Gela-1 well. ASPH (insoluble in n-alkane) and maltene (MALT, soluble in n-alkane) fractions of oil were separated using n-pentane, n-hexane, n-heptane and n-decane solvents. The ASPH contents of the Sciacca and Noto oils (26–33wt%) are notably higher compared to the Streppenosa oil (7–12wt% ASPH).We present an optimized Re–Os procedure with sample digestion in a high-pressure asher, followed by isotopic measurements using negative thermal ionization mass spectrometry. Very high metal contents of Gela oils allowed acquisition of precise Re–Os data. Systematic variations between the type of solvent used for ASPH precipitation and the ASPH content of the oil (also known from the literature) and the Re–Os contents of the ASPH and MALT fractions (first observed in this study) provide important practical applications for Re–Os analyses of oil. Most Re and Os (∼96–98%) in the Noto oil are hosted in the ASPH fraction. In contrast, a significant portion of Re and Os (∼33–34%) is stored in the MALT fraction of the lighter, but heavily biodegraded Streppenosa oil.Collectively, our new data on alkane distribution, hopane and sterane biomarkers, major and trace element contents, and Re–Os concentrations and isotopic ratios of the oils and their fractions support the presence of two oil families. Streppenosa oil, a heavily biodegraded oil generated at an early stage of thermal maturation from a shaly source rock, is clearly distinct from the Noto and Sciacca oils, both generated at peak maturation from a carbonate source rock with no subsequent biodegradation.Two Re–Os ages were obtained. Crude oil and ASPH from Noto and Sciacca oil yield a Model 1 isochron age of 27.5±4.6Ma with an initial 187Os/188Os of 3.89±0.43 (MSWD=1.6, n=19). We interpret this Oligocene age as the time of initial oil generation, that was probably related to the onset of regional collisional tectonics in southern Sicily. ASPH and crude oil from the Streppenosa oil yield scattered data, perhaps related to effects of biodegradation. Streppenosa MALT yield a Model 1 age of 200.0±5.2Ma and initial 187Os/188Os of 1.39±0.11 (MSWD=0.52; n=4). This age and initial Os-isotopic composition are consistent with rapid oil generation shortly after Late Triassic source-rock formation, perhaps driven by magmatic-related heating.Here we document a potentially powerful geochronological tool that can be applied to single samples of crude oil. Within each oil, the 187Os/188Os and most of the 187Re/188Os ratios in the MALT fractions are lower than in the corresponding ASPH fractions. Crude oils, being physical mixtures of ASPH and MALT, have intermediate Re–Os isotopic ratios. Hence, the needed spread in data points for a Re–Os isochron is obtained by analyzing components of a single crude oil. This approach eliminates pitfalls in interpretation of Re–Os data from multiple oils with possibly different generation, migration, or reservoir modification history.

Preliminary study of metalloporphyrins in some oil shales, red sea, Egypt

Occurence and distribution of metalloporphyrins were studied in asphaltene and maltene fractions of some Egyptian oil shales from the main producing mines (Abu-Shegeili, El-Beida, El-Nakheil and Abu-Tundub I, II) in red sea area (Fig. 1).Metalloporphyrins were extracted using adsorption column chromatography. The presence of Ni, Fe and Vo-porphyrins was monitored in each fraction by means of UV–Visible spectrometry, the result indicated that metalloporphyrins could be a mixture of Etio and DPEP types. Each fraction using UV–Visible spectrometry cannot differentiate between Ni and Fe porphyrins, so the extracted metalloporphyrins were subjected to purification and separation from each other by using thin layer chromatography (TLC).HPLC was used for fingerprinting Vo, Ni and Fe-porphyrins, it was found that the different porphyrins exhibited wide different chromatograms. HPLC technique could be used as a successful tool to characterize Fe and Ni-porphyrins.

Improving Recycled Asphalt Mix Performance Through Rejuvenation

Developing technologies that provide sustainable solutions for future pavement construction is vital given the ever-increasing demand on the supply of bitumen and good-quality pavement construction materials. Recycled asphalt pavement (RAP) is a technology that presents many advantages in cost and environmental savings. This study investigated the performance of RAP mixes containing rejuvenation additives to determine the effects of those additives on the deformation (rutting) resistance, cracking resistance, and fatigue performance of RAP mixes. Laboratory testing was conducted on 11 RAP mixes that were manufactured with RAP proportions of 15% and 30%, as well as with the addition of different types of rejuvenating agents. Results produced useful performance indicators for the use of rejuvenation additives in RAP. The mixes that had rejuvenation additives preserved the high deformation resistance of RAP mixes, particularly at the higher RAP proportion of 30% when compared with a mix with no RAP, and concurrently the addition of rejuvenators counteracted against overstiffening effects of RAP. The addition of RAP, especially 30% RAP proportion, had poorer fatigue performance than when only 15% RAP was used, but with the use of rejuvenation agents, the fatigue performance of the high RAP mixes improved significantly. Use of a maltene fraction for RAP rejuvenation had marginally better fatigue performance than a chemical rejuvenation agent. The research results provide a valuable understanding of the behavior of RAP mixes and, in particular, the positive performance results that can be gained by using rejuvenation additives.

Detection of residual oil-sand-derived organic material in developing soils of reclamation sites by ultra-high-resolution mass spectrometry.

The reconstruction of disturbed landscapes back to working ecosystems is an issue of increasing importance for the oil sand areas in Alberta, Canada. In this context, the fate of oil-sand-derived organic material in the tailings sands used for reclamation is of utmost environmental importance. Here we use electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry of maltene fractions to identify compositional variations over a complete oil sand mining and recultivation process chain. On the basis of bulk compound class distributions and percentages of unique elemental compositions, we identify specific compositional features that are related to the different steps of the process chain. The double bond equivalent and carbon number distributions of the N1 and S1O2 classes are almost invariant along the process chain, despite a significant decrease in overall abundance. We thus suggest that these oil-sand-derived components can be used as sensitive tracers of residual bitumen, even in soils from relatively old reclamation sites. The patterns of the O2, O3, and O4 classes may be applied to assess process-chain-related changes in organic matter composition, including the formation of plant-derived soil organic matter on the reclamation sites. The N1O2 species appear to be related to unidentified processes in the tailings ponds but do not represent products of aerobic biodegradation of pyrrolic nitrogen compounds.

Producing absorption mode Fourier transform ion cyclotron resonance mass spectra with non-quadratic phase correction functions.

Previously described methods for producing absorption mode Fourier transform ion cyclotron resonance (FTICR) mass spectra have all relied on the phase correction function being quadratic. This assumption has been found to be invalid for some instruments and spectra and so it has not been possible to produce absorption mode spectra for these cases. The Autophaser algorithm has been adapted to allow nth order polynomial phase correction functions to be optimized. The data was collected on a modified Thermo LTQ FTICR mass spectrometer, using electrospray ionization and a novel ICR cell design (NADEL). Peak assignment and mass calibration were undertaken using the pyFTMS framework. An nth-order phase correction function has been used to produce an absorption mode mass spectrum of the maltene fraction of a crude oil sample which was not possible using the previous assumption that the phase correction function must be quadratic. Data processing for this spectrum in absorption mode has shown the expected benefits in terms of increasing the number of assigned peaks and also improving the mass accuracy (i.e. confidence) of the assignments. It is possible to phase-correct time-domain data in FTICRMS to yield absorption mode mass spectra representation even when the data does not correspond to the theoretical quadratic phase correction function predicted by previous studies. This will allow a larger proportion of spectra to be processed in absorption mode.

Solubility Of CO2 and C2H6 in heavy Oil and its Sara fractions

Solvent‐based recovery is one of the most promising techniques to enhance heavy oil/bitumen recovery as an alternative to thermal methods. Phase behaviour study of light gases in heavy oil is therefore very important when designing operation and surface facilities for heavy oil recovery. In this study, the original oil (Cactus Lake) was first characterized into saturate, aromatic, resin, asphaltene, and maltene fractions (0.0 wt. % asphaltene). An intelligent gravimetric microbalance was used to measure the solubility of carbon dioxide and ethane in the heavy oil and its saturate, aromatic, resin, asphaltene, and maltene fractions. The measurements were carried out at 288, 294, 299, and 303 K, and at pressures from 200 to 2000 kPa. The standard Peng‐Robinson equation of state was used to correlate the experimental results. The associated Henry's law constants were regressed and reported. The adsorbed amounts of carbon dioxide and ethane on asphaltene were correlated using the Freundlich isotherm. As for the given heavy oil sample and its fractions, carbon dioxide showed lower solubility than ethane at constant temperature, even at high pressures. It was observed that the asphaltene content affects ethane solubility quite significantly in this heavy oil when compared to carbon dioxide.

Impact of maltene and asphaltene fraction on mechanical behavior and microstructure of bitumen

As a widely accepted concept, bitumen consists of four fractions that can be distinguished by their polarity. Highly polar asphaltene micelles are dispersed in a viscous phase of saturates, aromatics and resins (maltene phase). Different concentrations of asphaltenes in the bitumen result in a range of mechanical response properties. In an interdisciplinary study the impact of the maltene phase and asphaltenes on the linear viscoelastic behavior and the microstructure of bitumen were analyzed by creep recovery testing in a DSR and by atomic force microscopy (AFM). Therefore, bitumen was separated into the maltene and asphaltene fractions and artificial bitumen samples with different, pre-defined asphaltene concentrations were produced and investigated. It was found that the artificially produced, precipitated bitumen samples can be regarded as a representative, bitumen-like material in terms of mechanical behavior and microstructure. Asphaltenes play an important role in the typical viscoelastic behavior of bitumen being mainly responsible for stiffness and elasticity. Also, their concentration appears to be correlated to the occurrence and shape of the bee-like inclusions which can be typically observed by AFM.

Characterization of oily sludge from a refinery and biodegradability assessment using various hydrocarbon degrading strains and reconstituted consortia

Oily sludge obtained from a refinery in India contained 10–11% oil associated with fine particulates. Along with Fe, Ca and Mg various toxic elements were associated with the sludge solids (Pb, Mn, Cu, Zn, As, Bi, Cd, Cr, Co, Ni and V). The oil contained 41–56% asphaltenes and the maltenes comprised of 49 ± 4%, 42 ± 2% and 4 ± 2%, aliphatic, aromatic and polar fractions, respectively. Biodegradation studies with the maltene fraction of oil provided as sole substrate revealed higher degradation by various 3-5 membered reconstituted consortia compared to pure bacterial strains and up to 42 ± 8% degradation could be achieved over 30 days. In contrast, over the same period up to 71.5 ± 2% oil degradation could be achieved using dried oily sludge (15% w/v) as sole substrate. Significant biodegradation observed in the un-inoculated controls indicated the presence of indigenous microorganisms in oily sludge. However, large variability in oil degradation was observed in the un-inoculated controls. Greater biodegradation of the maltene fraction led to significant enrichment of asphaltenes in residual oil associated with the sludge.

Thermal Analysis and Combustion Kinetic of Heavy Oils and Their Asphaltene and Maltene Fractions Using Accelerating Rate Calorimetry

This work presents an experimental study on the thermal and kinetic parameters of the oxidation reaction of heavy crude oils to support the in-situ combustion oil recovery technique. An accelerated rate calorimeter was used to investigate the thermal behavior of two Brazilian heavy oils in an open system under constant pressure and continuous heating to 550 °C. The goal was to identify and characterize several oxidation regions and to obtain the activation energy and reaction order. The temperature–time curves showed three clearly distinct regions. During the heating, autoignition was found to have started at 180–220 °C. Then, the reaction curves exhibit a strong exothermic behavior up to 250–350 °C, which represents the low-temperature oxidation. Asphaltenes were found to play a crucial role in the kinetic behavior of the crude oils. The results show that oxygen-addition reactions are dominant from 200 to 300 °C and that bond-scission reactions are dominant above 350 °C. Although the presence of sand and clay improves the contact between the oil and oxygen and accelerates both of these reactions, it has a greater impact on the oxygen-addition reactions. The results provide helpful data for the screening of crude oils as candidates for recovery by in-situ combustion.

Solubility and diffusivity of propane in heavy oil and its SARA fractions

The design and modelling of solvent‐based heavy oil recovery requires information about the solubility and diffusivity of particular solvents in heavy oil and its fractions. In this study, the original Cactus Lake oil was first characterized into saturate, aromatic, resin, asphaltene, and maltene fractions. An intelligent gravimetric microbalance was used to measure the solubility of propane in the heavy oil and its saturate, aromatic, resin, asphaltene, and maltene fractions. The measurements were carried out at 288, 294, 299 and 303 K, and at pressures up to 600 kPa. From the experimental results, it was observed that the saturate fractions have the highest solubility followed by maltene, aromatic, heavy oil and resin fractions. Solubility data were also reported in the form of Henry's law constants. It was observed that the asphaltene content affects the propane solubility quite significantly in the heavy oil at the same equilibrium pressure. The Peng–Robinson equation of state was used to correlate the experimental results within acceptable deviations. The adsorbed amounts of propane in asphaltene were also measured at 288, 294, 299 and 303 K and at pressures up to 600 kPa to determine the adsorption capability of propane on asphaltene. Finally, time‐dependent concentration data were used to determine the diffusion coefficients of propane in heavy oil, saturate, aromatic and maltene fractions using a simple diffusion model. It was observed that the diffusion coefficient increases with pressure but decreases with the asphaltene content.

Geochemical characteristics and genetic types of the crude oils from the Iranian sector of the Persian Gulf

Comprehensive geochemical study shows genetic relationships among 33 crude oils from Iranian sector of the Persian Gulf and suggests the ages and paleoenvironments of their source rocks. The samples were collected from Jurassic to Tertiary reservoirs of 17 developed oil fields where about 15billion barrels of recoverable oil have been reserved. The oil density varies in rather wide range, between 12.2° and 39.2° API. Asphaltene contents ranged from 0.8–18.5%, and the maltene fractions are dominated by saturated HCs (29.3–70.9%) with subordinate proportions of aromatic HCs (22.30–38.30%) and polar compounds (7–15.70%). Pristane to phytane (Pr/Ph) ratios are variable (0.67–1.41). Sulfur content in crude oil samples are highly variable (0.65–3.7%). According to the Tissot and Welte’s classification, most of the oils can be classified as “high sulfur” oils. Statistical and geochemical results indicate that the studied oils belong to four main genetic groups:Group I oils (Jurassic to Early Cretaceous reservoirs of the Dorood, Kharg, Aboozar and Foroozan oil fields in the NW part of the Persian Gulf) originated from Jurassic or older carbonate rich source rocks deposited in an anoxic environment.Group II oils (Jurassic to Early Cretaceous reservoirs of the Salman, Resalat, Reshadat and Balal oilfields in the eastern part of the Persian Gulf) were sourced from Jurassic or older, carbonate source rocks deposited in a relatively oxic environment;Group III oils (Late Cretaceous to Tertiary reservoirs of the Aboozar, Bahregansar, Souroush, Nowrouz, Dorood and Kharg oilfields in the north/north-west part of the Persian Gulf) were probably sourced from Middle Cretaceous calcareous shales.Group IV oils (Late Cretaceous reservoir of the Sirri A, Sirri C, Sirri D, Sirri E, Resalat and Reshadat oilfields in the eastern part of the Persian Gulf) probably originated from mid to Late Cretaceous source rock.

Reactivity and stability of vacuum residual oils in their thermal conversion

Thirteen vacuum residual oils originating from Russia, Middle East, Asia, and South America were thermally cracked in a modified high-temperature–high-pressure batch autoclave reactor. It was found that the colloidal stability of the vacuum residual oils expressed by S-value was the dominant factor that affected the residue thermal reactivity. SARA analysis data of the residual oils were confirmed to contain insufficient information about residue thermal reactivity and colloidal stability. It was found that the higher the colloidal stability of a residual oil the lower residue thermal reactivity and the steeper colloidal stability reduction during thermal conversion. The asphaltene solubility was found to linearly decrease with the increase of the thermal conversion, while the maltene solubility power did not always decrease with the increase of the thermal conversion for the studied residual oils. Having in mind that the ebullated bed residue hydrocraking H-Oil process is also based on thermal conversion the properties of commercial straight run Urals vacuum residue (UVR), visbreaker residue obtained by thermal cracking of UVR (UVBR), and ebullated bed hydrocracking (H-Oil) unconverted residue were investigated. It was found that asphaltene solubility lowered linearly with increasing of conversion regardless of the process: visbreaking or ebullated bed hydrocracking. The maltene fraction average molecular weight seems to decrease with the increase of the residue thermal conversion processes visbreaking and ebullated hydrocracking as the asphaltene average molecular weight does for the same processes. It was found that the atmospheric gas oil fraction from visbreaker has no negative effect on residual oil colloidal stability while the vacuum gas oil fraction has negative impact on residue stability in both visbreaker and H-Oil unconverted residual oils. The data generated in this work study suggest that the asphaltene solubility has a bigger impact on the residual oil colloidal stability than the maltene solubility power.

Bitumen Paints, an Old Story with New Approach, Part-2, Water Based Paints

Bitumen paints have lost their importance but are still used for large area applications such as tanks and pipelines. It was determined that improving solvent based paint properties by physical or chemical modification by polymers was possible. Applying this approach for water based paints has shown that advance in properties such as hardness and drying times without loss in adhesion and flexibility can be obtained by blending of various polymeric emulsions with bitumen emulsions used for waterproofing membranes. Changes in morphology of the films occurred after blending, indicating interaction between bitumen maltene fractions and polymers. Physical modifications with styrene acrylic emulsions were more rewarding than elastomeric or chemically modifying crosslinking emulsions.

Characterization of Acidic Compounds in Heavy Petroleum Resid by Fractionation and Negative-Ion Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Analysis

Negative-ion electrospray ionization (ESI) enabled the direct mass spectrographic analysis of phenols, naphthenic acids, and neutral nitrogen compounds in petroleum fractions without prefractionation; however, ESI results provide few quantitative and structural information about the analytes: the composition of acidic compounds in heavy oil, such as distillate resid, is still unclear. In this study, extrography was used to fractionate oilsands bitumen-derived vacuum-topped bitumen (VTB) and its maltene and asphaltene fractions into multiple subfractions. The molecular compositions of acidic functional compounds in the VTB and its subfractions were analyzed by negative-ion ESI Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Extrographic separation was a necessary step to isolate acidic compounds of various acidities and/or polarities in vacuum resid fractions to achieve a systematic analysis. The results showed that the O2 class species in VTB were highly condensed phenols and carboxylic acids. The maltene fraction contained most of the less condensed naphthenic acids, whereas the asphaltene fraction contained highly condensed carboxylic acids and phenolic compounds with a bouble-bond equivalent (DBE) higher than 6. The presence of acids had no significant impact on the yield of asphaltenes in n-C7 solvent precipitation. Acid-free asphaltene fractions, which account for more than 90 wt % of the asphaltenes, cannot be ionized by negative-ion ESI.

Acidic and Neutral Polar NSO Compounds in Heavily Biodegraded Oils Characterized by Negative-Ion ESI FT-ICR MS

Five heavily biodegraded tar sand bitumens from an oil column were separated into maltene and asphaltene fractions for analysis by negative-ion electrospray (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). These bitumens have an identical source, which have experienced a natural sequence of biodegradation. The polar NSO compounds in maltene fractions contain O1, S1O1, O2, S1O2, S2O2, O3, S1O3, O4, S1O4, N1, N1O1, N1O2, N1S1, and S1 classes, while the polar NSO compounds in asphaltene fractions contain O1, S1O1, S2O1, O2, S1O2, S2O2, O3, S1O3, S2O3, O4, S1O4, S2O4, O5, S1O5, S2O5, O6, N1, N1O1, N1O2, N1O3, N1S1, and N2 classes. Polar NSO compounds with stronger molecular polarity and larger molecular weight are readily fractionated into asphaltene fractions. The O2 class is prevalent in polar NSO compounds of both maltene and asphaltene fractions of all bitumen samples. The N1 class in maltene fractions is dominated by compounds with DBE values of 9, 10, 12 and 13, while the N...