Decomposition Of Oil Research Articles

Time-varying Relationship between Oil Prices, Stock Market Performance, and Covid-19 in United States of America, China, and Malaysia: Evidence from Wavelet Approach

The purpose of this paper is to have a better understanding of the reactions to the oil price and stock market performance over a different period of the Covid-19 pandemic from January 2019 to August 2022 (Pre Covid, During Covid, and Post Covid) in the United States of America, China, and Malaysia. In the study, various approaches such as line graphs, descriptive statistics, correlation, wavelet correlation, continuous wavelet transform, and wavelet coherence analysis were used to analyse the decomposition of time series oil and stock market data in different time period. The study provides evidence of positive linear relationships between crude oil prices with the 3 countries’ stock markets in pre-covid, during-Covid and post-covid. In addition, both oil price and stock prices have evidence of a lead-lag relationship with each other, which differs in the period of time. The research results will benefit investors for better prediction during future pandemic situations and economic crises.

Study on the Inhibition Effect of C6F12O on Charged Particles in the Flame of Transformer Oil Discharge Gas

ABSTRACT The accidental combustion of insulating oil poses a significant risk in the event of transformer failure. The charged particles generated through the combustion ionization reaction exert considerable influence on the combustion speed and stability of the flame. Therefore, the detailed chemical reaction mechanism including neutral matter and charged particle is simplified. The two-dimensional finite rate reaction model is established. The theoretical calculation investigates the suppressive effect of the novel fire extinguishing agent C6F12O on charged particles in the flame resulting from transformer oil decomposition. The analysis encompasses changes in flame temperature, free radicals, and charged particles in the decomposition gas of transformer oil under C6F12O concentrations ranging from 0% to 4%. The findings reveal that the addition of C6F12O exerts a discernible inhibitory effect on the flame temperature of the transformer oil exhaust gas. The large reduction of charged particles in the flame caused by C6F12O is achieved by its consumption of large amounts of O and OH radicals in the flame. It hampers key elementary reactions responsible for charged particle generation. In conclusion, C6F12O demonstrates a pronounced inhibitory effect on charged particles in the flame resulting from transformer oil decomposition.

Effect of sesame protein/PVA nanofibers on oil separation and rheological properties in sesame paste

AbstractThis study aimed to prevent or minimize the oil phase separation that occurs during storage (0‐90 days) of sesame paste at room temperature. In order to determine the changes during storage in the sesame paste samples, the zeta potential, rheological properties, and the separated oil ratio were determined. Significant (p < 0.01) effects of applied storage time and additives on the amount of oil separated in sesame pastes were determined. The oil separated in sesame paste samples varied between 3.83% and 16.29%. While the rate of separated oil increased three times in the control group over time, it showed an insignificant (p > 0.05) increase especially in the samples where 2% nanofiber was added. It was determined that the separation of the oil phase from the structure could be prevented up to 24.73% with the addition of SPI and up to 63.02% with addition of SPINL (nanofiber containing protein isolate) compared to the control.Practical applicationsDuring storage, the particles in the sesame paste tend to precipitate, causing oil separation and residue cake, thus negatively affecting the acceptability of consumers. Additives were added in order to prevent or minimize oil phase separation, which occurs in sesame paste stored at room temperature and is not desired by consumers. As additives, nanofibers containing sesame proteins produced by the electrospinning method and sesame protein isolates (SPIs) were added. Added additives acted by preventing the separation of the oil phase from the structure. It has been determined that the addition of SPI to sesame pastes does not completely prevent the problem of oil separation in sesame paste, but is effective in delaying and reducing it. Since the oil decomposition can be reduced, the amount of oil separated and therefore the part that can sink to the bottom will decrease, so sesame paste will be consumed more appropriately and will contribute to the country's economy.

Modified Cinnabaris-stabilized Pickering emulsions loaded with the essential oil of Acorus tatarinowii Schott: preparation, characterization and in vitro evaluation.

Essential oil of Acorus tatarinowii Schott (ATEO) have significant biological activity, but their physical and chemical properties are unstable and susceptible to interference by external factors, resulting in oxidation, decomposition, and isomerization of essential oils (EOs), ultimately diminishing the quality of EOs and escalating clinical risks. In this research, based on the concept of " combination of medicine and adjuvant, " the unsuitable stabilizer Cinnabaris in Lingzhu powder prescription was modified with a SiO2 surface to become a stabilizer suitable for Pickering emulsion. The modified Cinnabaris was synthesized, with a focus on exploring the surface modification of Cinnabaris to facilitate its role as a stabilizer in Pickering emulsion. Thermal stability studies showed that modified Cinnabaris-stabilized emulsion had higher EOs retention and lower peroxide value and hydrogen peroxide content. GC-MS analysis showed that the volatile components in the emulsion were more stable than the EOs. In vitro dissolution experiments showed that in the dissolution medium of artificial gastric juice and artificial intestinal juice, compared with the ATEO, the release in Pickering emulsion was faster within 48 h, indicating that the ATEO had been encapsulated in Pickering emulsion, which could improve the in vitro dissolution rate of EOs. This study convincingly demonstrates the potential of modified Cinnabaris-stabilized Pickering emulsion to improve the thermal stability and in vitro dissolution rate of EOs.

Effects of natural and prolonged crude oil pollution on soil enzyme activities

In this study the effects of natural and long-term oil pollution levels (H: high, M: moderate and L: low) on the activity of lipase, β-glucosidase, urease, phosphatase, and dehydrogenase were analyzed. For this purpose, 120 oil-contaminated soil samples were collected from four locations located in oil-rich region of the west of Iran (Kermanshah province, Iran). After determining the physicochemical characteristics of soils, microbial counting and enzyme activities were measured. To determine the total bacterial population and bacteria involved in crude oil decomposition, bacterial counting was done in NA and CFMM culture media, respectively, which had a direct relationship with the increase in crude oil content. The average percentage of crude oil measured by Soxhlet method was 4.03%, 9.95% and 22.50% respectively for L, M and H levels. The results showed that the bacterial population increased with the increase of the contamination intensity. All the studied enzymes, except urease, had the highest activity in heavily polluted soils (H soil), and their lowest activity was observed in lightly polluted soils (L soils). Location 1 had the highest bacterial population as well as the highest activity of dehydrogenase (52.13 μg TPFg−1 h−1), acid phosphatase (35.86 μg PNPg−1 h−1), alkaline phosphatase (78.13 μg PNPg−1 h−1), lipase (92.58 μ MLA g−1 h−1) and β-glucosidase (21.67 μg PNPg−1 h−1) enzymes. In the soil samples of location 4, which had the lowest number of bacteria, the highest activity of urease enzyme (592.36 μg NH4g−1 h−1) was obtained. Principal components analysis (PCA) was also performed and 67% of the cumulative of the samples could be explained by the first two components (biochemical and physical). The findings of this research showed that natural and prolonged crude oil pollution caused the selection of oil-resistant microbial communities, and therefore we saw their positive response to the presence of oil compounds and increased enzyme activity other than urease activity.

ReaxFF Molecular Dynamics Study on the Microscopic Mechanism for Kerogen Pyrolysis.

Kerogen is mainly composed of carbon, hydrogen, and oxygen, which are the main components of crude oil and gas. The pyrolysis of kerogen is an efficient method to generate clean energy. In the present work, the pyrolysis reaction process of three types of kerogen is simulated using ReaxFF molecular dynamics (MD) methods to study the microscopic mechanism and the distribution of products. The results indicated that the pyrolysis products of the three types of kerogen significantly depend on the molecular structures, temperature, and reaction time. As the temperature increases, the gaseous hydrocarbon and the light and heavy oil fractions decreased, where small molecular fragments polymerized to form new molecular fragments. For an isothermal temperature, with the reaction proceeding, some component polymerization of the pyrolyzed fragments occurred, resulting in the generation of new light oils and heavy oils. Moreover, quantum chemical analysis was employed to reveal the kerogen pyrolysis mechanism. First, the weak bonds such as C-O, C-N, and C-S structures were decomposed to generate large carbon and some heavy shale oil fragments. Second, the cycloalkanes and long-chain alkanes were decomposed to generate a large amount of light shale oil and gaseous hydrocarbons. Finally, the decomposition of C═C in the aromatic ring, the secondary decomposition of light and heavy shale oils, and the further decomposition of short-chain alkanes occurred. In addition, the production of hydrogen (H2) occurred at the late stage of the pyrolysis reaction. Hydrogen radicals were formed by the decomposition of C-H bonds and subsequently collided with each other, resulting in the formation of H2 molecules. The pyrolysis and chemical analysis of kerogen can clearly determine the type and content of hydrocarbon substances, providing scientific data for exploration, development, and utilization of shale gas and shale oil.

Kinetics of thermal decomposition of crude oils: Insights from principal component analysis and products characterization

Energy demand is souring, and fossil fuel reserves are dwindling, making heavy oil resources more attractive. In this study, thermogravimetric and Py-GC/MS analyses were conducted on Iranian crude oil samples to compare high and low API (American Petroleum Institute) crude oils. A kinetic study based on mass loss of crude oil was performed using three model-free methods and distributed activation energy model (DAEM). To do that, TG analysis carried out, the temperature was increased from room temperature to 1000 °C with heating rates of 10, 20, and 30 °C min−1. Activation energy (Ea) and pre-exponential factor (A0) were estimated from Friedman, Kissinger–Akahira–Sunose (KAS), and Ozawa-Flynn–Wall (OFW) methods for oil sample. The Ea and A0 for heavy crude oil (Koroosh) pyrolysis varied between 59.85 and 193.83 kJ mol−1 and 1.34 × 105 to 4.36 × 1011 s−1, respectively. For light crude oil sample Lavan, the Ea and A0 ranged between 35.93 to 62.89 kJ mol−1 and 337.41–722.65 s−1, respectively. Pearson's correlation analysis found that the activation energy barrier increases as the reaction progresses and the temperature rises. This makes it harder to form the activated complex, which is a key step in the reaction. Principal component analysis supported these findings. Saturated and aromatic hydrocarbons were liberated at mild temperature while the resins and asphaltenes consecutively released in favorable condition for developing sustainable heavy oil recovery systems. Py/GC–MS analysis shows the evolution of saturated hydrocarbon in Koroosh-oil and aromatic hydrocarbons in Lavan-oil and demonstrates their suitability for fuel applications.

Study of the kinetics of aviation oils thermal conversion under non-isothermal conditions

The paper discusses the results of a kinetic study of the thermal decomposition of MS-8P, TN-98, and TN-600 aviation oils under conditions of continuous heating at a constant rate of 5 K/min to a temperature of 1 073 K. An integral method was used to describe the reaction mechanism and determine the macrokinetic parameters. It has been established that, from a phenomenological point of view, the average reaction of aviation oils conversion under the experimental conditions corresponds to the reaction model described by the surface-limited reaction equation (MS-8P), the power law (TN-98) and the model described by the three-dimensional diffusion-limited reaction equation (TN-600). When dividing the averaged reaction into two reactions (the first is completed at a temperature of 550–600 K, the second at a temperature of 638–655 K), it is determined that the first reaction is described by the reaction equation of the 2nd order (MS-8P), the first order (TN-98) and the reaction equation of one-dimensional diffusion (TN-600), and the second the reaction equation of the first order (three types of oil). The activation energy of the first reaction was 99 kJ/mol (MS-8P), 145.6 kJ/mol (TN-98) and 57.4 kJ/mol (TN-600), the value of the pre-exponential factor was – 144 241 567 min–1 (MS-8P), 62 161 395 942 min–1 (TN-98) and 236.16 min–1 (TN600). The activation energy of the second reaction is 160 kJ/mol (MS-8P), 91.6 kJ/mol (TN-98) and 127.1 kJ/mol (TN-600), the pre-exponential factor is 8.81 ‧ 1011 min–1 (MS-8P), 1.26 ‧ 104 min–1 (TN-98) and 2.04 ‧ 108 min–1 (TN-600). It is shown that the use of these values of the activation energy and the pre-exponential factor leads to agreement between the calculated values of the degree of decomposition of the studied oil samples and the experimental ones in the range of values of the degree of decomposition from 0 to 1.

Catalytic pyrolysis of straight-run light oil to light olefins: Role of molecular structure and catalytic materials

The development of straight-run light oil catalytic pyrolysis to light olefins process is an important approach of achieving the transformation and upgrading of the current oil refining industry. However, the industrialization of the catalytic pyrolysis process for straight-run light oil has been slow. Herein, we investigated the decomposition of complex straight-run light oil into different structural units and further examined their effects on light olefins production. The results indicated that the yields of light olefins cracked over MFI zeolite were about 45 % and 30 % for alkane structure and cycloalkane ring structure, respectively. Further analysis showed that the olefin structure could theoretically be cracked to 100 % light olefins, but in fact, 40 % of the light olefins were lost due to the transfer of 10 % hydrogen. Subsequently, the effects of zeolite topology and acid properties on the cracking of different structural units were further analyzed. It was found that zeolites with MTT and MFI topologies contributed to the catalytic pyrolysis of chain and cycloalkane ring structures, respectively, because appropriate pore size helped diffusion of hydrocarbon molecules and inhibited side reactions such as hydrogen transfer. Compared with MFI zeolite, the light olefins yield produced by chain structure cracking over MTT zeolite increased by 5.83 %-10.54 %. In addition, it was discovered that zeolites with total and strong acids in the range of 0.2–0.4 mmol/g and 0.1–0.2 mmol/g, respectively, were beneficial for the cracking of light alkanes in straight-run light oils to light olefins. This work provides useful insights into the fundamental understanding and development of straight-run light oil catalytic pyrolysis to light olefins process.

The Prokaryotic Community Structure of Oil-Contaminated Chernozem during the Introduction of Nitrate and Potassium Chloride

The effect of nitrate and potassium chloride salts, on the structure of the metabolically active prokaryotic community of oil-contaminated chernozem has been studied. Molecular biological approaches and bioinformatic methods of analysis were used in the study. The objects of the study were samples of chernozem selected in the Voronezh region (N 51°1′41″, E 40°43′31″). The phylogenetic and functional diversity of the prokaryotic complex of oil-contaminated chernozem was considered when introducing nitrate and potassium chloride under conditions of a slightly alkaline reaction of the medium. Contamination of chernozem with oil in an amount of 5% of the soil mass led to alkalinization of the medium from 7.1 to 7.9. The introduction of nitrate and potassium chloride, both separately and together in a total dose of 2 mmol/100 g of soil removed this negative effect. The combined addition of nitrate and potassium chloride led to a more than twofold increase in the biomass of metabolically active prokaryotic cells and the number of copies of functional genes responsible for the synthesis of alkanmonooxygenase enzymes involved in the decomposition of oil. In the presence of oil, the formation of a specific complex of bacteria was revealed, in which representatives of A-ctinobacteria (Rhodococcus erythropolis) and Alphaproteobacteria (Bradyrhizobium japonicum) prevailed. Rhodococcus erythropolis and Bradyrhizobium japonicum, being autochthonous organisms in uncontaminated soil, began to occupy dominant positions in oil-contaminated samples, and the introduction of nitrates enhanced this effect.

Adsorption of SF6 gas and insulating oil decomposition gas by CoO-doped SnSe monolayer in various environments: A study of strong adsorption performance

Taking into account that Sulfur hexafluoride (SF6) gas leakage can result in environmental pollution, the insulating oil used in high-voltage equipment can decompose into various detectable dissolved gases, allowing for the monitoring of its operational status. In this study, we use a CoO-doped SnSe (SnSe-CoO) monolayer to achieve strong adsorption of SF6 gas, CO, and C2H2 gas, and highly sensitive monitoring of H2 and CH4. Thus, the SnSe-CoO monolayer can serve as an adsorbent for SF6 gas leakage and a material for monitoring insulating oil-dissolved gas. Furthermore, we also observed that the adsorption energy of each gas on the intrinsic material increases with the solvent dielectric constant, facilitating the control of gas adsorption. Our research provides a significant theoretical foundation for future adsorption and monitoring of insulating gases and insulating oil decomposition gases.

Enzymatic Assessment of the State of Oil-Contaminated Soils in the South of Russia after Bioremediation.

Soil pollution with oil as a result of accidents at oil pipelines and oil refineries is a frequent occurrence in the south of Russia. To restore such polluted lands, it is necessary to carry out soil remediation measures. This work aimed to evaluate the use of ameliorants of various natures (biochar, sodium humate, and microbial preparation Baikal EM-1) to restore the ecological state of oil-contaminated soils with different properties (Haplic Chernozem, Haplic Arenosols, Haplic Cambisols). To assess the ecological state of soils, the following physicochemical and biological indicators were studied: residual oil content, redox potential, and medium reaction (pH). Changes in enzymatic activity were also studied, including catalase, dehydrogenases, invertase, urease, and phosphatase. The greatest decomposition of oil in Haplic Chernozem and Haplic Cambisols was provided by Baikal EM-1 (56 and 26%), and in Haplic Arenosols, this was provided by biochar (94%) and sodium humate (93%). In oil-contaminated Haplic Cambisols, the content of easily soluble salts with the addition of biochar and Baikal EM-1 increased by 83 and 58%, respectively. The introduction of biochar caused an increase in pH from 5.3 (Haplic Cambisols) to 8.2 (Haplic Arenosols). The introduction of oil-contaminated Haplic Arenosols of biochar, humate, and Baikal stimulated the activity of catalase and dehydrogenases by 52-245%. The activity of invertase was stimulated in the Haplic Chernozem after the introduction of ameliorants by 15-50%. The activity of urease was stimulated after the introduction of ameliorants into borax and Arenosol by 15-250%. The most effective ameliorant for restoring the ecological state of Haplic Cambisols after oil pollution was biochar. For Haplic Arenosols, this was sodium humate, and for Haplic Chernozem, the effectiveness of biochar and sodium humate did not differ. The most informative indicator for the remediation of Haplic Chernozem and Haplic Cambisols was the activity of dehydrogenases, and for Haplic Arenosols, this was the activity of phosphatase. The results of the study should be used to biomonitor the ecological state of oil-contaminated soils after bioremediation.

Incorporation of wet gases to kerogen in petroleum formation and evolution

The formation mechanism for thermogenic gas remains unresolved. Disputes are focused on: (1) stability barrier for decomposition of oil to gas and wet gas to methane, and (2) inconsistence in dryness ratio (C1/ΣC1–5) between gases produced in pyrolysis experiments and in natural reservoirs. Here, we demonstrate the variation trend of dryness ratio (C1/ΣC1–5) with temperatures and thermal stress levels, and the correlation of dryness ratios with the yields of liquid components (ΣC8+) in confined pyrolysis experiments (gold capsules) of twenty coals. At both heating rates of 2 and 20 °C/h, dryness ratios of gaseous hydrocarbons at first decrease, and then increase with increasing temperatures and thermal stress levels. Dryness ratios of produced gases can be very high in the range of 66.3–95.7 wt% at initial temperature about 334 °C and heating rate of 20 °C/h, corresponding to EASY%Ro 0.56. We suggest that these gases are not the original products released from kerogen, but have been altered via wet gas incorporation to kerogen. Larger oil molecules (C8+) are more competitive in incorporating to kerogen compared with wet gases, and therefore, prohibit wet gas incorporation, leading to the observed trend of gas dryness ratios with increasing temperature and maturity and the negative correlation between dryness ratios and the yields of liquid components (ΣC8+). The conflicting results between the yields and carbon isotopes of wet gases produced in the isothermal confined pyrolysis experiments for coal plus oil can be well interpreted using the reaction mechanism that wet gases incorporate to kerogen while oil components retard this incorporation. Once free oil and wet gas molecules are reincorporated to kerogen, the bound molecules can easily decompose to smaller molecules due to substantial reduction of activation energy for carbon-carbon bond rupture. Petroleum formation from kerogen can be a recycling process: kerogen first releases oil compounds, and then free molecules reincorporate to kerogen and further decompose to smaller molecules, and finally to methane.

Manganese Oxide Loaded Carbon Fiber for Solar Energy Harvesting and Oil Decomposition

In this work, a manganese oxide electrode, containing carbon nanofiber composites (MnO2/CNF), has been made through electrospinning, oxidization, and partial carbonization high-temperature treatment. Scanning electron microscopy (SEM) was used to observe the morphology of the nanofiber and analyze the composition of the fiber. The fiber size range and element distribution were determined. The oxide nanoparticles were modeled as electrorheological suspensions in the polyacrylonitrile polymer solution during electrospinning. The dielectrophoretic behavior of the particles subjected to non-uniform electric fields were analyzed and the motion of the oxide particles under the actions from fluctuating electric fields was investigated to explain the sporadic distribution of nanoparticles within the composite nanofibers. A photoactive anode was made from the composite nanofiber and the decomposition of spilled oil was performed under sunlight illumination. It was observed that the manganese oxide containing carbon nanofiber composite electrode can generate electricity and clean the spilled oil under sunlight. Both energy conversion and environment cleaning concepts were demonstrated.

STUDY OF OIL DEGRADATION IN OIL-CONTAMINATED SOIL DURING PURIFICATION USING A BIOLOGICAL PRODUCT

During a scientific study, a laboratory experiment was conducted to investigate the degradation of oil by various microorganisms in a liquid mineral medium containing 2% oil. This experiment was conducted at temperatures of 24ºC and 5ºC for a duration of 10 days. Using infrared spectroscopy (IR spectroscopy), the degree of oil decomposition by each microorganism was determined. Based on these data, four associations of microorganisms were created, which proved to be effective in breaking down oil hydrocarbons. Using gravimetry and IR spectrometry, the degree of oil biodegradation by these microorganism associations was assessed, ranging from 30% to 70%. Based on the data obtained regarding microbial associations, a new bio-preparation was developed, containing the Pseudomonas sp. K3-H strain and two Rhodococcus strains (F2/2-Н4, F2/1-Н4). Subsequently, fieldwork was conducted on the premises of oil waste of the company "TOO Company – Daulet Asia." Over a period of 12 weeks, the population of oil-degrading microorganisms at the oil-contaminated site reached the required level, resulting in an 89.67% reduction in the amount of oil. It is worth noting that the ambient temperature varied from 05 to 39°C during the day and from 0 to 24°C at night during this period. The results of the field studies demonstrated the effectiveness of the developed bio-preparation based on the Rhodococcus erythropolis KZ1, Rhodococcus erythropolis KZ2, and Pseudomonas putida KZ3 strains. Thus, the proposed bioremediation strategy utilizing the developed bio-preparation successfully passed the testing phase at the landfill of "TOO Company - Daulet Asia" in the Kyzylorda region of the Republic of Kazakhstan.

Features of the self-restoration of the oil-contaminated peat-bog soil – a field study

The features of self-restoration processes of the oligotrophic peat-bog soil disturbed by crude oil pollution were studied. Soil contamination was carried out in field long-term experience. The key soil self-recovery indicators were: (1) the rate of carbon dioxide emission by the soil, which quantitatively characterizes the mineralization of petroleum hydrocarbons by microorganisms; (2) content of petroleum products. The microorganisms of the studied soil were characterized by low resistance to the toxic effects of oil: during the first three years of the experiment, the respiration of oil-contaminated soils was significantly lower than in pure soil. Restoration of microbial respiration to the control level and its further intensive growth occurred after 4-5 years of the experiment only in soils with low oil doses: 0.3 and 0.6 l m-2. In time, this coincided with the maximum rate of oil decomposition, which indicates the microbial nature of its utilization. The respiration of soil with oil high doses (1.8 and 3.0 l m-2) remained significantly lower than in pure soil throughout the entire experiment. At the same time, the amount of oil products in these samples markedly decreased. Oil degradation in these variants could occur due to the activity of anaerobic bacteria or abiotic processes.

Thermal decomposition characteristics of the tire pyrolysis oil derived from a twin-auger reactor: Study of kinetics and evolved gases

This study presents the characterization of the thermal decomposition (oxidation and pyrolysis) behavior of the oil (TPO) derived from the pyrolysis of End-of-Life Tires (ELT) in a twin-auger pyrolyzer, by means of thermogravimetric and calorimetric analyses, coupled with Fourier transform infrared spectroscopy (TG–FTIR). TPO oxidation and pyrolysis were conducted using air and N2, respectively, at three different heating rates (5, 10, and 20 °C/min) in a temperature range between 30 and 700 °C. Along the temperature program, the evolved gases were directed to the FTIR cell, where the functional groups within species present were measured. A global kinetic analysis was performed for the TPO oxidation, using four isoconversional methods, as well as the distributed activation energy model (DAEM) developed by Miura and Maki. The results obtained suggest that the oxidation process of TPO can be divided into three different reaction stages, namely: low-temperature oxidation (LTO) (<400 °C), fuel decomposition (400–500 °C), and high-temperature oxidation (HTO) (500–700 °C). Within the LTO stage, oxygen addition reaction to produce hydroperoxides were considered dominant in the initial stages, while the decomposition of the formed hydroperoxides was more significant at the later stage. Due to the characteristics of TPO, e.g., the presence of highly volatile compounds, the evaporation of hydrocarbons played an important role within the LTO stage. In the fuel decomposition stage, the formation of coke by the oxidative cracking of LTO residue and oxygen addition were believed to be the main reactions leading to gaseous products such as CO, CO2, H2O. Finally, in the HTO stage, the oxidation of coke was considered as the main reaction, exhibiting an evident exothermic activity. The activation energy distribution shows a similar pattern among the isoconversional methods and DAEM, with fluctuations between 40 and 200 kJ/mol. The analysis presented in this work sheds new light on the thermal decomposition of oil derived from the pyrolysis of ELT, which is relevant for its use in combustion systems.

Causes of variation in the concentration and distribution of H2S in carbonate reservoirs of the Feixianguan Formation, Lower Triassic in the eastern Sichuan Basin

Hydrogen sulfide (H2S) has been encountered in many oil and gas fields worldwide, causing potentially various health and safety issues; thus, it is crucial to assess its concentration before drilling. Natural gas from the Feixianguan carbonates in the Jiannan gas field is predominantly composed of methane with various H2S concentrations varying from very minor to 3.71%. However, the H2S concentrations display obvious difference, ranging from 0.18% to 0.81% in the southern zone and 0.21–3.71% in the northern zone, with high concentrations (>1%) occurring selectively in dolomitized reservoirs in the northern zone. Based on petrographic and geochemical data and reactive transport numerical modeling, the H2S origin and sulfate sources were analyzed for understanding factors controlling the H2S concentration and distribution.In the northern zone containing high H2S concentrations, there is a common mineral assemblage of pyrobitumens, burial calcite cements, pyrite, and hemispherical elemental sulfur in dolomite reservoirs. Burial calcite cements, often coated by pyrobitumens, have higher precipitation temperatures (>106 °C), and lighter δ13C ratios than host dolostones, suggesting the incorporation of organic carbon into the precipitation of these high-temperature burial calcites supplied by thermochemical sulfate reduction (TSR). Numerical modeling indicates the SO42− concentrations of pore waters would increase significantly in dolomitized domains during seawater-involved dolomitization, consisting with the fact of the higher SO42− concentrations of pore waters in the northern zone. The dolomitizing fluids delivered sulfates into reservoirs which were inevitably reduced by hydrocarbons, once the reaction temperature was reached. Comparatively, in the southern zone where carbonates were not subjected to intensive dolomitization and the SO42− concentrations of pore waters were low, the H2S originated only from the thermal decomposition of oil and organic matter (<1%). This study implies that hydrocarbon exploration in dolomitized reservoirs should be given greater caution because of the more favorable conditions for H2S generation.

Method for assessing the efficiency of the use of a biological preparation in wastewater of oil extraction production

One of the promising ways to remove fats in the wastewater of food enterprises is the bioenzymatic technology for the decomposition of organic substances, including fats and vegetable oils, at local treatment facilities located directly at the enterprises. Bioenzymatic technologies for the decomposition and utilization of fats in wastewater are based on the use of microbial lipases and microorganisms capable of producing them. The experiment was carried out on the territory of the oil extraction plant in Bezenchuk for 18 days. Based on the samples taken, the concentration of triglycerides was revealed, the destructive ability was determined, as well as lipolytic activity after the introduction of the biological product.

Enhancing the Recovery of Bioactive Compounds of Soybean Fermented with Rhizopus oligosporus Using Supercritical CO2: Antioxidant, Anti-Inflammatory, and Oxidative Proprieties of the Resulting Extract.

The aim of the present study was to evaluate the use of supercritical CO2 combined with cosolvent for the recovery of bioactive compounds of soybean fermented with Rhizopus oligosporus NRRL 2710. Soxhlet extractions using seven different organic solvents (n-hexane, petroleum ether, ethyl acetate, acetone, ethanol, methanol, and water) were initially performed for comparative purposes. The extracts obtained were characterized by physicochemical, antioxidant, total phenolic, and oxidative proprieties. For the Soxhlet extractions, the highest and lowest yields obtained were 45.24% and 15.56%, using methanol and hexane, respectively. The extraction using supercritical CO2 combined with ethanol as a static modifier (scCO2 + EtOH) presented, at a high pressure (25 MPa) and temperature (80 °C), a phenolic compound content of 1391.9 μg GAE g−1 and scavenging of 0.17 g, reaching a 42.87% yield. The extracts obtained by sCO2 + EtOH were characterized by high contents of essential fatty acids (linoleic acid and oleic acid) and bioactive compounds (gallic acid, trans-cinnamic acid, daidzein, and genistein). These extracts also showed a great potential for inhibiting hyaluronidase enzymes (i.e., anti-inflammatory activity). Thermogravimetric analyses of the samples showed similar profiles, with oil degradation values in the range from 145 to 540 °C, indicating progressive oil decomposition with a mass loss ranging from 93 to 98.7%. In summary, this study demonstrated the flexibility of scCO2 + EtOH as a green technology that can be used to obtain high-value-added products from fermented soybean.