Search Results (79)

Omniphobic membranes have gained extensive attention for mitigating membrane wetting in robust membrane separation owing to the super-repulsion toward water and oil. In this study, a Teflon/PAI composite membrane with omniphobic characteristics was prepared by a vacuum-assisted dip-coating strategy on the PAI hollow fiber membrane. A series of characterizations on morphological structure, surface chemical composition, wettability, permeability, mechanical properties, and stability were systematically investigated for pristine PAI and Teflon/PAI composite membranes. Subsequently, the experiment was conducted to explore the oil–gas separation performance of membranes, with standard transformer oil containing dissolved gas as the feed. The results showed that the Teflon AF2400 functional layer was modified, and C-F covalent bonds were introduced on the composite membrane surface. The Teflon/PAI composite membrane exhibited excellent contact angles of 156.3 ± 1.8° and 123.0 ± 2.5° toward DI water and mineral insulating oil, respectively, indicating omniphobicity. After modification, the membrane tensile stress at break increased by 23.0% and the mechanical performance of the composite membrane was significantly improved. In addition, the Teflon/PAI composite membrane presented satisfactory thermal and ultrasonic stability. Compared to the previous membranes, the Teflon/PAI composite membrane presented a thinner Teflon AF2400 separation layer. Furthermore, the omniphobic membrane demonstrated anti-wetting performance by reaching the dynamic equilibrium within 2 h for the dissolved gases separated from the insulating oil. This suggests an omniphobic membrane as a promising alternative for oil–gas separation in monitoring the operating condition of oil-filled electrical equipment online. Full article

Crude oil accounts for approximately 40% of global energy consumption, and the refining sector is a major contributor to greenhouse gas (GHG) emissions, particularly through the production of hard-to-abate fuels such as aviation fuel and fuel oil. This study disaggregates the refinery into its key process units to identify decarbonization opportunities along the entire production chain. Units are categorized into combustion-based processes—including crude and vacuum distillation, hydrogen production, coking, and fluid catalytic cracking—and non-combustion processes, which exhibit lower emission intensities. The analysis reveals that GHG emissions can be reduced by up to 60% with currently available technologies, without requiring major structural changes. Electrification, residual heat recovery, renewable hydrogen for desulfurization, and process optimization through digital twins are identified as priority measures, many of which are also economically viable in the short term. However, achieving full decarbonization and alignment with net-zero targets will require the deployment of carbon capture technologies. These results highlight the significant potential for emission reduction in refineries and reinforce their strategic role in enabling the transition toward low-carbon fuels. Full article

This paper addresses the critical challenge of insufficient solid-phase suction capacity in jet pumps during vacuum sand cleanout operations for low-pressure oil and gas wells. Through integrated numerical simulations validated by experimental measurements with under 15% error, a kind of nonlinear interaction mechanism among key operational and solid-phase parameters is revealed in this paper. The results demonstrate that due to intensified turbulent dissipation, particle diameters exceeding 0.5 mm will lead to a significant decrease in pump efficiency, while an increase in solid volume fraction can improve the solid transport rate but will reduce the energy conversion efficiency. Working pressure optimization shows that the pump efficiency will reach its maximum when the work pressure is 5 MPa, while if it is 8 MPa, the solid transport capacity will be increased by 116%. A discharge pressure exceeding 2.5 MPa will reduce the suction pressure difference and disrupt solid phase transport. A novel dual-metric framework considering the solid transport rate and pump efficiency is put forward in this paper, which includes limiting the particle diameter to 0.5 mm or less, maintaining a solid volume fraction below 30%, and keeping the working pressure between 5 and 8 MPa and the discharge pressure at 2.5 MPa or lower. This method can increase the sand removal efficiency to over 30% while minimizing energy loss, providing a validated theoretical basis for sustainable wellbore repair in depleted oil reservoirs. Full article

This research systematically investigates the influence of high-energy ball-milling (BM) parameters on the acidic and textural properties of zeolite Y. Among the BM parameters, the milling time (MT) exerted a more significant influence on the zeolite degradation than milling speed (MS), primarily affecting particle size and crystallinity. Milling produced nanozeolites with particle sizes ranging from 210 to 430 nm, and their activity was tested in the catalytic cracking of vacuum gas oil (VGO). The highest catalytic activity was observed for the zeolite with a particle size of 397 nm and a crystallinity of 75.9%: the VGO conversion was 69.0%, and the gasoline fraction yield was 33.9%, compared to the parent zeolite’s 62.7% and 22.1%, respectively. It was found that the activity of milled zeolites in catalytic cracking is determined by the accessibility of acid sites, which can be controlled by forming an optimal micro-mesoporous structure. Full article

The production of very-low-sulfur residual fuel oil is a great challenge for modern petroleum refining because of the instability issues caused by blending incompatible relatively high-sulfur residual oils and ultra-low-sulfur light distillates. Another obstacle in the production of very-low-sulfur residual fuel oil using hydroprocessing technology is the contradiction of hydrodesulfurization with hydrodemetallization, as well as the hydrodeasphaltization functions of the catalytic system used. Therefore, the production of very-low-sulfur residual fuel oil by employing hydroprocessing could be achieved by finding an appropriate residual oil to be hydroprocessed and optimal operating conditions and by controlling catalyst system condition management. In the current study, data on the characteristics of 120 samples of heavy fuel oils produced regularly over a period of 10 years from a high-complexity refinery utilizing H–oil vacuum residue hydrocrackers in its processing scheme, the crude oils refined during their production, the recipes of the heavy fuel oils, and the level of H–oil vacuum residue conversion have been analyzed by using intercriteria and regression analyses. Artificial neural network models were developed to predict the characteristics of hydrocracked vacuum residues, the main component for the production of heavy fuel oil. It was found that stable very-low-sulfur residual fuel oil can be manufactured from crude oils whose sulfur content is no higher than 0.9 wt.% by using ebullated bed hydrocracking technology. The diluents used to reduce residue viscosity were highly aromatic FCC gas oils, and the hydrodemetallization rate was higher than 93%. Full article

The quality of the catalytic cracking feed can affect the conversion by 35%, while the activity of the catalyst can influence the conversion by 11% and the reaction temperature by 15%. The pivotal role of feed quality justifies the investigations directed to better understanding which components of the feed impinge the conversion, yields, selectivity and properties of the catalytic cracking products. In this research, two virgin vacuum gas oils, a hydrotreated vacuum gas oil and five sulfuric acid-treated vacuum gas oils were cracked on a commercial equilibrium catalyst (Nova DAO) in a micro-activity (MAT) unit at different catalyst-to-oil ratios to obtain the conversion, yields, and selectivities at the point of maximum gasoline yield. The treatment of one of the virgin and the hydrotreated vacuum gas oils with sulfuric acid decreased the heavy aromatics from 22.6 to 0.0 wt.% and resins from 2.7 to 0.0 wt.%. Intercriteria analysis of the experimental cracking data revealed that the reduction and removal of the heavy aromatic compounds from the vacuum gas oil had a profound effect on conversion, yields, and gasoline quality. It led to conversion enhancement from 70.8 to 86.1 wt.% and a reduction of gasoline research octane number by two points. The conversion at the maximum gasoline yield was confirmed to be very well predicted by a correlation that includes the empirical parameters aromatic carbon and hydrogen contents with %AAD of 0.7 wt.% and maximum absolute deviation of 2.3 wt.%. Full article

The FeZn-MOFs@Al₂O₃ catalyst was synthesized under solvothermal conditions. Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), temperature-programmed desorption of ammonia (NH₃-TPD), and specific Brunauer–Emmett–Teller (BET) surface area and pore volume were used to systematically investigate the effects of different parameters such as molar ratio of iron to zinc, synthesis temperature, and synthesis time on the properties of the materials. The results showed that the optimum synthesis conditions of FeZn-MOFs@Al₂O₃ composites were 140 °C for 1 h, and the optimum molar ratio of Fe³⁺ and Zn²⁺ was 1.3:0.7. Under the aforesaid conditions, FeZn-MOFs@Al₂O₃ had the deacidification rate of vacuum gas oil (VGO) up to 96.3%. The optimum esterification parameters were as follows: the amounts of catalyst and ethylene glycol were, respectively, 2.5 wt% and 4.0 wt% of the sample oil, the reaction temperature was 250 °C, and the reaction time was 1 h. Full article

Oil production will remain essential in the coming decades, requiring environmental responsibilities that are aligned with Agenda 2030. Enhanced oil recovery (EOR) increases recovery efficiency with low investment, but environmental protection technologies (EOR and Env), including green EOR (GEOR) and waste treatment (WT), must be integrated. The BRICS association, representing half of global oil production, promotes technology transfer in this context. Worldwide patent data (2004–2023) of EOR and Env technologies at TRL 4–5 in BRICS and non-BRICS countries were compared for nine GEOR (1489 patents) and nine WT (2292 patents) methods. China is the global leader (73%, being 98% of BRICS patents), maintaining dominance even when normalized by GDP. Non-BRICS patents are from the USA (41%), Japan (31%), and the Republic of Korea (14%). BRICS countries surpassed non-BRICS in 2014, with a 5.9% growth rate, −13.2% for non-BRICS, with all methods growing, whereas in non-BRICS, only water flocculation treatment is growing. BRICS technological specialization is expanding more rapidly than that of non-BRICS countries. BRICS countries exhibit higher relative technological advantages and distance in surfactants, polymers, macromolecules, sludge treatment, and multistage water treatment devices. Non-BRICS countries are more competitive in in situ combustion, water alternating gas (WAG), re-pressurization, vacuum techniques, flotation, water–oil separation, sorption, or precipitation, flocculation, and oil-contaminated water. China is the primary BRICS leader and is positioned to define BRICS policies regarding technology transfer and innovation. Technological partnerships between BRICS and non-BRICS countries are strongly recommended to enhance synergy and achieve sustainable and efficient production more rapidly. Full article

The primary extraction way for unconventional oil/gas resources is hydraulic fracturing to alter the reservoir for commercial production. However, hydraulic fracturing technology consumes a large amount of water, and the flowback water can easily be mixed with hydrocarbon substances to form emulsions. To achieve the recycling of water, it is necessary to develop an efficient continuous demulsification method for treating the flowback fluid. In this study, a composite filtration layer with superhydrophilic and superoleophilic properties was successfully prepared using water-based polyurethane as a binder. The g-C₃N₄ was used to improve the affinity of the filtration layer to water and oil. The diatomite and rice husk carbon were used as an adsorbent and a filter aid, respectively. The contact angles (CA) of both oil and water on the surface of the filtration layer were measured to be 0°. During the demulsification process, vacuum filtration was employed to increase the pressure difference across the filtration layer, thereby improving the treatment flux of flowback fluid. The experimental results showed that the filtration flux with the addition of rice husk charcoal increased from 160.58 L∙m⁻²∙h⁻¹ to 174.68 L∙m⁻²∙h⁻¹ compared to the filter layer without rice husk charcoal. Based on the composite filtration layer, the apparent demulsification efficiency exceeded 90.6% for various types of emulsion. The mechanism of demulsification was investigated by the molecular dynamics method. The results showed that the adsorption layer density of water molecules reached 1.5 g/cm³, and the adsorption layer density of oil molecules exceeded 2.5 g/cm³. The porous structure wall has a strong adsorption effect on both oil and water molecules, resulting in deformation and destruction of the oil–water interface, so that the dispersed phase is adsorbed and aggregated by the filter layer at the same time and permeates from the filter layer after reaching saturation, thus separating the two phases. Full article

This study evaluates the impact of the catalyst-to-oil (C/O) ratio in the 1 to 7 range on the catalytic cracking of vacuum gas oil (VGO). Experiments are conducted using fluid catalytic cracking (FCC)-type catalysts, in a mini-fluidized bench-scale Riser Simulator reactor invented at the Chemical Reactor Engineering Centre (CREC), University of Western Ontario. The CREC Riser Simulator replicates FCC industrial operating conditions such as temperature, species partial pressure, and reaction times. The results indicate that increasing the C/O ratio above 5 slightly impacts VGO conversion, increases light gases yield, decreases light cycle oil (LCO) yield, and stabilizes gasoline yield. These findings align with temperature-programmed desorption (TPD) data, showing how the retention of a larger number of acid sites at a C/O of 7 boosts light gas production and reduces LCO selectivity. These elevated C/O ratios also lead to higher coke formation. The results reported together with future studies conducted by our research team on the impact of higher catalyst flows, larger potential catalyst attrition, higher catalyst loading in the cyclones, and excess heat generated in the catalyst regenerator unit, are of critical value for establishing the impact of C/O ratios in the overall FCC refinery operation. Full article

This study combined gas chromatography–ion mobility spectrometry (GC-IMS) and multivariate statistical analysis to explore the differences in the characteristic aroma of Idesia polycarpa Maxim (I. polycarpa) fruit and oil under different drying methods: natural drying (ND), hot air drying (HAD), microwave drying (MD), and microwave vacuum drying (MVD). The results revealed that 91 volatile compounds were identified in the fruit, and 82 were found in the oil of I. polycarpa. HAD and MD resulted in the most significant loss of volatile aroma in both the fruit and oil. In contrast, MVD demonstrated the best retention of these volatile aromas. Multivariate statistical analysis and odor activity value (OAV) analysis (OAV ≥ 1) were employed to identify 10 volatile aroma compounds considered differentiating factors in the fruit and oil subjected to different drying methods. These compounds, including hexanal, 3-methylbutyric acid, 2-acetylpyridine, guaiacol, valeraldehyde, and butyric acid, significantly contribute to the flavor characteristics of I. polycarpa fruit and oil, evoking notes of nuts, caramel, and sourness. The OAVs of these aroma-differentiating compounds in microwave vacuum-dried fruit and oil were higher compared to those from other drying methods. Therefore, when considering the enhancement of volatile flavor compounds, MVD is more effective than the other drying methods in promoting the formation of flavor compounds in I. polycarpa fruit and oil. Full article

Hybrid layered reinforced materials are able to increase the reliability, durability, and expand the functionality of high-temperature components in supercritical and ultra-supercritical power plants and in oil, gas, and petrochemical equipment operating under conditions with multifactorial influences (temperature, force, deformation). As a result of this research, surface reinforced ceramic composite materials with a gradient distribution of properties have been developed. These materials include thermal barrier layers (Gd₂O₃-Yb₂O₃-Y₂O₃-ZrO₂) and Ni-based layers reinforced with ceramic carbide and oxide particles. They are strong, have a high heat and wear resistance, and provide the specified functional and mechanical properties. The formation technology for the hybrid composites has also been developed. This technology includes the mechanical alloying of powder compositions, which is followed by vacuum plasma spraying. The structure of the powder compositions and composite layers, the density of the obtained composite materials, and the heat and wear resistance of the composites have also been investigated. The microhardness of the alloy layers of the hybrid composite materials Hastelloy X–GYYZO–material 1 and Hastelloy X–GYYZO–material 2 was as follows: super alloy Hastelloy X, HV_0.2 = 3.8–3.95 GPa; layer GYYZO, HV_0.3 = 16.1–16.7 GPa; layer material 1, HV_0.3 =18.3–18.8 GPa; layer material 2, HV_0.3 =19.1–19.6 GPa. The influence of the refractory phase of HfC and TaC on the strength of the composites was studied. It was found that the maximum strength (710–715 MPa) in the composites Hastelloy X—GYYZO—material 1 and Hastelloy X–GYYZO–material 2 is achieved with a content of HfC and TaC–27–28%. Full article

This paper introduces a new methodology for a routine metal analysis of plastic waste (PW) and PW blended with petroleum feedstock such as vacuum gas oil and VGO (PW/VGO). For such purposes, recycled polyethylene and polypropylene plastic were selected to mimic the potential feeds to be integrated at the Fluid Catalytic Cracking unit (FCC) to produce valuable products. Elements such as P, Ca, Al, Mg, Na, Zn, B, Fe, Ti, and Si were included in the method development. Different sample preparation methods were evaluated, such as microwave-assisted acid digestion (MWAD) and dry/wet ashing, followed by a fusion of the ash with lithium borate flux. Some PW homogenization pretreatments, such as cryogenic grinding and hot press molding, were also covered. The finding of this work suggests that MWAD with HNO₃ and H₂O₂ is adequate for both types of samples and is the quickest sample preparation; however, the sample needed to be homogenized, and recoveries for Si and Ti may be biased for PW due to the limited solubilities of these elements in the nitric acid media. Carbon removal is required before fusion sample preparation and analysis due to the amount of carbon in PW samples. The sample needed to be homogenized for wet ash fusion but not for the pre-ash (dry) method. A benefit to the damp ash pretreatment is that the ash for the sample was created in the same crucible used for fusion digestion, avoiding material loss during sample management. Fusion from wet ash or carbon removal allowed for better acid solubility for Si and Ti in PW. The results of the PW samples evaluated matched well with those of both sample preparation methodologies. For most elements, precision was <10% regardless of the sample preparation; however, Fe and P had some variation using wet ash fusion, possibly due to contamination in an open digestion system or variation due to being close to the method limit of quantification (LOQ). The methodology reported here is robust enough to be implemented as routine analysis in any laboratory facility. Full article

The influence of residual cuts on the deactivation of hierarchical Y zeolite-based catalysts during the co-processing of vacuum gas oil (VGO) with atmospheric residue (ATR) was investigated. The experiments were conducted in a laboratory-scale MAT-type reactor. The conversion of VGO, ATR, and their 70:30 (mass basis) mixture was examined using two composite catalysts: Cat.Y.0.00 and Cat.Y.0.20. The operating conditions closely resembled those of the commercial catalytic cracking process (550 °C and contact times of 10 to 50 s). When ATR was processed individually, the conversion remained below 50 wt%. However, significant improvements in conversion rates were achieved and catalyst deactivation was mitigated when ATR was co-processed with VGO. Notably, the BET surface area and average mesopore volume were adversely impacted by ATR, which also led to the accumulation of high levels of metals and nitrogen on the spent catalyst, detrimentally affecting its acidic and structural properties. Moreover, substantial coke deposition occurred during ATR cracking. The soluble and insoluble coke analysis revealed H/C ratio values of up to 0.36, indicative of polycondensed coke structures with more than ten aromatic rings. The nature of the coke was confirmed through TPO and FTIR analyses. Interestingly, the CatY.0.20 catalyst exhibited less activity loss, retaining superior acid and structural properties. Co-processing Colombian atmospheric residue with ATR loadings of 30 wt% (higher than the typical 20 wt%) in catalysts formulated with hierarchical zeolites presents a promising alternative for commercial applications. This research opens avenues for optimizing catalytic cracking processes. Full article

Petroleum refining has been, is still, and is expected to remain in the next decades the main source of energy required to drive transport for mankind. The demand for automotive and aviation fuels has urged refiners to search for ways to extract more light oil products per barrel of crude oil. The heavy oil conversion processes of ebullated bed vacuum residue hydrocracking (EBVRHC) and fluid catalytic cracking (FCC) can assist refiners in their aim to produce more transportation fuels and feeds for petrochemistry from a ton of petroleum. However, a good understanding of the roles of feed quality and catalyst characteristics is needed to optimize the performance of both heavy oil conversion processes. Three knowledge discovery database techniques—intercriteria and regression analyses, and artificial neural networks—were used to evaluate the performance of commercial FCC and EBVRHC in processing 19 different heavy oils. Seven diverse FCC catalysts were assessed using a cascade and parallel fresh catalyst addition system in an EBVRHC unit. It was found that the vacuum residue conversion in the EBVRHC depended on feed reactivity, which, calculated on the basis of pilot plant tests, varied by 16.4%; the content of vacuum residue (VR) in the mixed EBVRHC unit feed (each 10% fluctuation in VR content leads to an alteration in VR conversion of 1.6%); the reaction temperature (a 1 °C deviation in reaction temperature is associated with a 0.8% shift in VR conversion); and the liquid hourly space velocity (0.01 h-1 change of LHSV leads to 0.85% conversion alteration). The vacuum gas oil conversion in the FCC unit was determined to correlate with feed crackability, which, calculated on the basis of pilot plant tests, varied by 8.2%, and the catalyst ΔCoke (each 0.03% ΔCoke increase reduces FCC conversion by 1%), which was unveiled to depend on FCC feed density and equilibrium FCC micro-activity. The developed correlations can be used to optimize the performance of FCC and EBVRHC units by selecting the appropriate feed slate and catalyst. Full article