Display omitted
•Co-injection of surfactant & nanocatalyst decreases oil viscosity by 62% via synergistic pathways.•Surfactant unpacks asphaltenes, enabling nanocatalyst to crack heavy compounds into ...lighter fractions.•Quantification verifies synergistic improvements in key metrics vs conventional methods.•Analysis of nanostructured sediments shows surfactant-nanocatalyst interactions.
Thermal recovery methods using steam injection are widely employed for heavy oil and bitumen production, but upgrading challenges persist with these highly viscous feeds. Although metal-based catalysts promote viscosity reduction in aquathermolysis, drawbacks remain. This work pioneers an eco-friendly technique coupling co-injection of tailored nonionic surfactant and heterogeneous nanocatalyst with steam. The mechanism of converting asphaltene in highly viscous crude oil through the combination of a catalyst and a heat-resistant surfactant is not well-understood. It is hypothesized that the surfactant facilitates the breakdown of asphaltene aggregates, allowing the catalyst to reach sulfur-containing structures within the asphaltenes, thereby increasing the conversion of asphaltenes with the formation of low-molecular-weight hydrocarbons. The nanocatalyst was synthesized and fully characterized by XRD, FTIR, SEM, and EDX. Batch hydroprocessing of heavy crude with surfactant was performed in a stirred reactor-GC system. Detailed structural analysis involved SARA fractions, elemental analysis, FTIR, and EPR. GC–MS probed changes in hydrocarbon types. Results revealed synergistic hydrogenation of polyaromatic compounds by the nanocatalyst-surfactant, decreasing resins and asphaltenes 17% and 30%, respectively. The surfactant further upgraded the oil by reducing carbon content and increasing the H/C ratio from 1.32 to 2.09, while improving hydrodesulfurization and hydrodenitrogenation. This innovative co-injection method enables more efficient, eco-friendly aquathermolysis and heavy oil upgrading. The approach shows promise for unlocking the full potential of thermal recovery processes through customized surfactant and nanocatalyst co-addition with steam.
Oxidation of heavy and extra-heavy oils is recognized as a complicated process due to the heterogeneous nature of its reaction medium and the lack of knowledge concerning its reaction mechanisms. The ...next decade is likely to witness a considerable rise in the use of in situ combustion to extract heavy and extra-heavy oils. However, a major issue of the in situ combustion is the instability of the combustion front. For this reason, application of catalysts was viewed as a way to initiate the process early and stabilize the resultant combustion front. In this study, we have synthesized an efficient precursor of iron-containing catalyst, studied its effect on heavy-oil oxidation by estimating the heat-flow-rate changes occurring during the oxidation process as a function of heating at different rates using differential scanning calorimetry, and investigated its transformation throughout the oxidation process by estimating its mass loss with heating at the rate of 10 °C min–1 using thermogravimetric analysis. In addition, we studied the morphology and size of the final product of oxidation obtained at 500 °C using scanning electron microscopy. At the end of the study, we compared its effect to that of the previously studied manganese tallate on heavy-oil oxidation. The kinetic parameters of the processes have been obtained by means of applying Kissinger method (isoconversional principle). Interestingly, iron tallate has been found to decrease the activation energy of both low-temperature and high-temperature oxidation regions. In addition, the values of effective reaction rate constants of both regions (low-temperature oxidation and high-temperature oxidation) increased in the presence of iron tallate as well. Moreover, it has been suggested that the iron oxide nanoparticles formed in situ are responsible for the resulting catalytic effect.
High mineralization of water complicates the use of foam in reservoir conditions. Anionic–nonionic surfactants are one of the best candidates for these conditions since they have both high surface ...activity and salt tolerance. One of the ways to obtain anionic–nonionic surfactants is to modify nonionic surfactants by an anionic group. The type of the group and its chemical structure can strongly affect the properties of the surfactant. In this work, widely-produced nonionic surfactant nonylphenol (12) ethoxylate (NP12EO) was modified by new types of carboxylic groups through the implementation of maleic (NP12EO-MA) and succinic (NP12EO-SA) anhydrides with different saturation levels. The main objectives of this work were to compare synthesized surfactants with nonionic precursor and to reveal the influence of unsaturated bonds in the carboxyl group on the properties of the foam. NaCl concentration up to 20 wt% was used to simulate high mineralization conditions, as well as to assess the effect of unsaturated bonds on foam properties. Synthesized anionic–nonionic surfactants retained surfactant solubility and long-term stability in high-salinity water, but have better foaming ability, as well as higher apparent viscosity, in porous media. The presence of an unsaturated bond in NP12EO-MA surfactant lowers foaming ability at high mineralization.
In the present work, we studied the catalytic performance of an oil-soluble nickel-based catalyst during aquathermolysis of oil-saturated crushed cores from Boca de Jaruco extra-heavy oil field. The ...decomposition of nickel tallate and some aspects of in-situ transformation of the given catalyst precursor under the steam injection conditions were investigated in a high-pressure batch reactor using XRD and SEM analysis methods. The changes in physical and chemical properties of core extracts after the catalytic aquathermolysis process with various duration were studied using gas chromatography for analyzing gas products, SARA analysis, GC-MS of saturated and aromatic fractions, FT-IR spectrometer, elemental analysis, and matrix-activated laser desorption/ionization (MALDI). The results showed that nickel tallate in the presence of oil-saturated crushed core under the injection of steam at 300 °C transforms mainly into nonstoichiometric forms of nickel sulfide. According to the SEM images, the size of nickel sulfide particles was in the range of 80–100 nm. The behavior of main catalytic aquathermolysis gas products such as CH4, CO2, H2S, and H2 depending on the duration of the process was analyzed. The catalytic upgrading at 300 °C provided decrease in the content of resins and asphaltenes, and increase in saturated hydrocarbon content. Moreover, the content of low-molecular alkanes, which were not detected before the catalytic aquathermolysis process, dramatically increased in saturates fraction after catalytic aquathermolysis reactions. In addition, the aromatics hydrocarbons saturated with high molecular weight polycyclic aromatic compounds—isomers of benzo(a)fluorine, which were initially concentrated in resins and asphaltenes. Nickel sulfide showed a good performance in desulfurization of high-molecular components of extra-heavy oil. The cracking of the weak C–S bonds, which mainly concentrated in resins and asphaltenes, ring-opening reactions, detachment of alkyl substitutes from asphaltenes and inhibition of polymerization reactions in the presence of catalytic complex reduced the average molecular mass of resins (from 871.7 to 523.3 a.m.u.) and asphaltenes (from 1572.7 to 1072.3 a.m.u.). Thus, nickel tallate is a promising catalyst to promote the in-situ upgrading of extra-heavy oil during steam injection techniques.
This paper discusses the role of magnetite in the conversion of heavy oil from the Ashal’cha reservoir. The effect of catalysts on the in-situ upgrading of heavy oil is directed on the reduction of ...high-molecular components of oil such as resins and asphaltenes and their molecular masses. Moreover, it is directed on the significant increase in saturates and aromatic fractions. Measuring the temperature-dependent viscosity characteristics revealed the tremendous viscosity decrease of the obtained catalytic aquathermolysis products. X-ray analysis exposed the composition of the initial catalyst that consisted of mixed iron oxides (II, III), as well as catalysts that were extracted from the treated crude oil. The particle size of the catalysts was investigated by scanning electron microscopy. According to the SEM data, aggregates of 200 nm were formed that were in the range of ultra-dispersed particles (200 to 500 nm).
In order to evaluate the efficiency of the catalytic aquathermolysis process, physical modeling was carried out on bituminous sediments of Paleocene–Miocene carbonate rocks, characterized by the ...presence of open and closed fractures. In this context, three filtration experiments were performed on an unextracted reservoir model with extra-viscous oil (EVO). Prior to the experiments, the mineral composition of the rock was determined by X-ray diffraction analysis (XRD) and the content of organic matter and coking products was determined before and after the experiment by thermogravimetric analysis (TGA) as well as the group composition of oil (SARA) before and after the experiment by nuclear magnetic resonance (NMR), gas composition at the fluid separation line, and oil displacement coefficient (ODC). The results of the conducted experiments show that the efficiency of displacement of extraviscous oil could be significantly increased by the use of a solvent and the combined use of a solvent and a catalyst (+9.3% and +17.1% of the oil displacement coefficient, respectively), which is associated with the processes of oil refining.
Increasing the efficiency of thermal recovery methods is an important and relevant task. This study is devoted to reducing heavy components (resins and asphaltenes) and quality improvement of heavy ...oil by catalytic hydrothermal treatment. The object of this study is a bituminous sandstone sample from the Ashal’cha reservoir. The catalytic (iron tallate) hydrothermal simulation was carried out under reservoir conditions (200 °C, 30 bar). The composition and physicochemical characteristics of the products were studied using elemental and SARA analysis, MALDI, GC-MS, FT-IR. Moreover, the extracted rock is analyzed in XRD and DSA (Drop Shape Analyzer). The introduction of catalyst in combination with a hydrogen donor reduces the content of resins by 22.0%wt. with an increase in the share of saturated hydrocarbons by 27%wt. The destructive hydrogenation leads to a decrease in the sulfur content of upgrading products. This is crucial for the oil reservoirs of the Tatarstan Republic, as their crude oils are characterized by high sulfur content. According to the wettability data, the hydrophilicity of the rock surface increases due to inhibition of the coke formation after the introduction of the catalytic complex. Thus, the oil recovery factor can be increased due to the alteration of the oil-wetting properties of reservoir rocks.
Aquathermolysis is one of the crucial processes being considered to successfully upgrade and irreversibly reduce the high viscosity of heavy crude oil during steam enhanced oil recovery technologies. ...The aquathermolysis of heavy oil can be promoted by transition metal-based catalysts. In this study, the catalytic performance of two water-soluble catalysts Ni(CH3COO)2 and Zn(CH3COO)2 on the aquathermolytic upgrading of heavy oil at 300 °C for 24 h was investigated in a high pressure–high temperature (HP-HT) batch reactor. The comparison study showed that nickel acetate is more effective than zinc acetate in terms of viscosity reduction at 20 °C (58% versus 48%). The viscosity alteration can be mainly explained by the changes in the group composition, where the content of resins and asphaltenes in the upgraded heavy crude oil sample in the presence of nickel catalyst was reduced by 44% and 13%, respectively. Moreover, the nickel acetate-assisted aquathermolysis of heavy oil contributed to the increase in the yield of gasoline and diesel oil fractions by 33% and 29%, respectively. The activity of the compared metal acetates in hydrogenation of the crude oil was judged by the results of the atomic H/C ratio. The atomic H/C ratio of crude oil upgraded in the presence of Ni(CH3COO)2 was significantly increased from 1.52 to 2.02. In addition, the catalyst contributed to the desulfurization of crude oil, reducing the content of sulfur in crude oil from 5.55 wt% to 4.51 wt% The destructive hydrogenation of resins and asphaltenes was supported by the results of gas chromatography-mass spectroscopy (GC-MS) and Fourier-transform infrared (FT-IR) spectroscopy analysis methods. The obtained experimental results showed that using water-soluble catalysts is effective in promoting the aquathermolytic reactions of heavy oil and has a great potential for industrial-scale applications.
This paper is devoted to the study of aquathermolysis processes of heavy oil produced by CSS technology on Boca de Jaruco oil field. Various catalysts based on cobalt, nickel, iron and copper were ...used for intensification of in-situ upgrading processes of heavy oil. The first paper in series is presented results of transformation of crude oil and its saturate fraction after thermal treatment with and without catalysts by SARA analysis, MALDI mass-spectrometry, FTIR-spectroscopy and gas chromatography. It is revealed, that catalysts provide more deep conversion of asphaltenes and resins into lighter hydrocarbons. Particularly, for the given heavy oil, catalysts based on iron and nickel organic salts are more effective to reduce the content of high molecular weight components (asphaltenes). Saturates fraction after thermal treatment in presence of the catalysts is enriched with lighter alkanes in comparison to the crude oil treated without catalysts. Obtained results show that crude oil recovered by catalytic aquathermolysis processes will be better quality than the original oil in the place.
This paper discusses the physical simulation of aquathermolysis for heavy oil in the presence of minerals - dolomite and calcite. According to the SARA-analysis and IR-spectroscopy, the presence of ...calcite provides significant effects on the reduction of resins and asphaltenes, their condensability and aromaticity by destructing the least stable C-S-C bonds. Based on the results of gas chromatography, the thermal conversion of heavy oil increased the hydrocarbon content with homologous series of С19-С30. The analysis of geochemical coefficients revealed the high maturity of organic matters in thermally conversed heavy oil from model system with dolomite.
PDF
