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This study investigated the effect of silane-based silica (SiO2) Janus nanoparticles (JNPs) on stabilizing the foam generated by different types of gases. Two types of SiO2 JNPs were synthesized through surface modification using HMDS and APTS silane compounds. Static analyses were conducted to examine the impact of different concentrations of the synthesized nanoparticles in various atmospheres (air, CO2, and CH4) on surface tension, foamability, and foam stability. The results indicated that the synthesized SiO2 JNPs and bare SiO2 nanoparticles exhibited nearly the same ability to reduce surface tension at ambient temperature and pressure. Both of these nanoparticles reduced the surface tension from 71 to 58–59 mN m−1 at 15,000 ppm and 25 °C. While bare SiO2 nanoparticles exhibited no foamability, the synthesis of SiO2 JNPs significantly enhanced their ability to generate and stabilize gas foam. The foamability of HMDS-SiO2 JNPs started at a higher concentration than APTS-SiO2 JNPs (6000 ppm compared to 4000 ppm, respectively). The type of gas atmosphere played a crucial role in the efficiency of the synthesized JNPs. In a CH4 medium, the foamability of synthesized JNPs was superior to that in air and CO2. At a concentration of 1500 ppm in a CH4 medium, HMDS-SiO2 and APTS-SiO2 JNPs could stabilize the generated foam for 36 and 12 min, respectively. Due to the very low dissolution of CO2 gas in water at ambient pressure, the potential of synthesized JNPs decreased in this medium. Finally, it was found that HMDS-SiO2 JNPs exhibited better foamability and foam stability in all gas mediums compared to APTS-SiO2 JNPs for use in oil reservoirs. Also, the optimal performance of these JNPs was observed at a concentration of 15,000 ppm in a methane gas medium. [ABSTRACT FROM AUTHOR]

In recent years, the application of smart water and surfactant in order to improve oil recovery has attracted special attention in carbonate reservoirs. In this research, the effects of various salts in smart water and two surfactants of Cetyl Trimethyl Ammonium Bromide (CTAB) and Sodium Dodecyl Sulfate (SDS) on the wettability alteration of carbonate rock and IFT were studied. Besides, along with micromodel flooding, core flooding tests were conducted to assess the amount of oil recovery at reservoir conditions as an injection scheme was used. In this regard, the results illustrated that the presence of CTAB or SDS in seawater (SW) can act better in contact angle reduction compared to smart water. Also, a four times increase in the concentration of SO42− and removing Na+ from SW reduced the contact angle to 68° and 71°, respectively, being the best possible options to alter the carbonate surface wettability to more water-wet states. Moreover, in the second-order process in which the rock section was first placed in SW, and then was put in the smart solution (with or without surfactant), CTAB had a great effect on the wettability alteration. In the case of IFT reduction, although SW4Mg2+, compared to other ions, better decreased the IFT to 17.83 mN/m, SW + SDS and SW + CTAB further declined the IFT to 0.67 and 0.33 mN/m, respectively. Concerning different ions, divalent cations (Mg2+ and Ca2+) show better results in improving oil recovery factor. However, the combination of SW and surfactants has a more positive effect on boosting oil recovery, as compared to smart water flooding. It should be mentioned that the first-order injection is better than the second-order one since SW is flooded at first, and then, after the breakthrough, smart water is injected into the micromodel. In addition, the core flooding tests showed that SW + CTAB and SW + SDS in tertiary injection increased the oil recovery to about 59 and 57%, respectively, indicating that the presence of CTAB could be more effective than that of SDS. [ABSTRACT FROM AUTHOR]

In the current investigation, molecular dynamics (MD) and Grand Canonical Monte Carlo (GCMC) simulation as remarkable and competent approaches have been employed for understanding structural and transport properties of MMMs in the realm of gas separation. The two commonly used polymers i.e. polysulfone (Psf) and polydimethylsiloxane (PDMS) as well as zinc oxide (ZnO) nanoparticle (NP) were used to carefully examine the transport properties of three light gasses (CO2, N2 and CH4) through simple Psf, Psf/PDMS composite loaded by different amounts of ZnO NP. Also, the fractional free volume (FFV), X-ray diffraction (XRD), glass transition temperature (Tg), and Equilibrium density were calculated to scrutinize the structural characterizations of the membranes. Moreover, the effect of feed pressure (4–16 bar) on gas separation performance of simulated MMMs was investigated. Results obtained in different experiments showed a clear improvement in the performance of simulated membranes by adding PDMS to PSf matrix. The selectivity of studied MMMs was in the range from 50.91 to 63.05 at pressures varying from 4 to 16 bar for the CO2/N2 gas pair, whereas the corresponding value for CO2/CH4 system was found to be in the range 27.27–46.24. For 6 wt% ZnO in 80%PSf + 20%PDMS membrane, high permeabilities of 78.02, 2.86 and 1.33 barrers were observed for CO2, CH4 and N2 gases, respectively. The 90%PSf + 10%PDMS membrane with 2% ZnO had a highest CO2/N2 selectivity value of 63.05 and its CO2 permeability at 8 bar was 57 barrer. [ABSTRACT FROM AUTHOR]

In the relentless battle against the impending climate crisis, deep eutectic solvents (DESs) have emerged as beacons of hope in the realm of green chemistry, igniting a resurgence of scientific exploration. These versatile compounds hold the promise of revolutionizing carbon capture, effectively countering the rising tide of carbon dioxide (CO 2) emissions responsible for global warming and climate instability. Their adaptability offers a tantalizing prospect, as they can be finely tailored for a multitude of applications, thereby encompassing the uncharted territory of potential DESs. Navigating this unexplored terrain underscores the vital need for predictive computational methods, which serve as our guiding compass in the expansive landscape of DESs. Thermodynamic modeling and solubility prognostications stand as our unwavering navigational aides on this treacherous odyssey. In this direction, the COSMO-RS model intertwined with the captivating Stochastic Gradient Boosting (SGB) algorithm. Together, they unveil the elusive truths pertaining to CO 2 solubility in DESs, forging a path toward a sustainable future. Our quest is substantiated by two exhaustive datasets, a repository of knowledge encompassing 1973 and 2327 CO 2 solubility data points spanning 132 and 150 distinct DESs respectively, encapsulating a spectrum of conditions. The SGB models, incorporating features derived from COSMO-RS, as well as accounting for pressure and temperature variables, furnishes predictions that harmonize seamlessly with experimental CO 2 solubility values, boasting an impressive Average Absolute Relative Deviation (AARD) of a mere 0.85% and 2.30% respectively. When juxtaposed with literature-reported methodologies like different EoS, as well as Computational Solvation, and machine learning (ML) models, our SGB model emerges as the epitome of reliability, offering robust forecasts of CO 2 solubility in DESs. It emerges as a potent tool for the design and selection of DESs for CO 2 capture and utilization, heralding a sustainable and environmentally conscientious future in the battle against climate change. • Trained and tested two methodologies to predict precise CO 2 solubility in DESs. • Utilized extensive CO 2 solubility datasets encompassing diverse experimental conditions for robust validation. • SGB models, integrating COSMO-RS, exhibit high accuracy with AARD of 0.85% and 2.30% for two datasets. • The Leverage algorithm was applied to ensure the models' statistical reliability. • Surpassing other methodologies, SGB ensures vital precision in designing sustainable CO 2 capture. [ABSTRACT FROM AUTHOR]

In this study, we initially performed interfacial tension (IFT) tests to investigate the potential of using the Persian Gulf seawater (PGSW) as smart water with different concentrations of NaCl, KCl, MgCl2, CaCl2, and Na2SO4. Next, for each salt, at the concentration where IFT was minimum, we conducted contact angle, zeta potential, and micromodel flooding tests. The results showed that IFT is minimized if NaCl or KCl is removed from PGSW; thus, for solutions lacking NaCl and KCl, the IFT values were obtained at 26.29 and 26.56 mN/m, respectively. Conversely, in the case of divalent ions, minimum IFT occurred when the concentration of MgCl2, CaCl2, and Na2SO4 in PGSW increased. Specifically, a threefold rise in the concentration of Na2SO4 further reduced IFT as compared to optimal concentrations of MgCl2 or CaCl2. It should be mentioned that eliminating NaCl from PGSW resulted in the lowest IFT value compared to adding or removing other ions. Whereas the removal of NaCl caused the contact angle to decrease from 91.0° to 67.8° relative to PGSW and changed surface wettability to weakly water-wet, eliminating KCl did not considerably change the contact angle, such that it only led to a nine-degree reduction in this angle relative to PGSW and left wettability in the same neutral-wet condition. At optimal concentrations of MgCl2, CaCl2, and Na2SO4, only an increase in Na2SO4 concentration in PGSW could change wettability from neutral-wet to weakly water-wet. For solutions with optimal concentrations, the removal of NaCl or KCl caused the rock surface to have slightly higher negative charges, and increasing the concentration of divalent ions led to a small reduction in the negative charge of the surface. The results of micromodel flooding indicated that NaCl-free PGSW could raise oil recovery by 10.12% relative to PGSW. Furthermore, when the Na2SO4 concentration in PGSW was tripled, the oil recovery increased by 7.34% compared to PGSW. Accordingly, depending on the conditions, it is possible to use PGSW so as to enhance the efficiency of oil recovery by removing NaCl or by increasing the concentration of Na2SO4 three times. [ABSTRACT FROM AUTHOR]

Since the development of science and technology has motivated researchers to find economic solutions in order to reduce energy consumption and environmental pollutants, it is essential to recognize the application membranes in separation industries. The present research has scrutinized pure gas separation to evaluate the effectivity of the composite of nano-poly(4-methyl-1-pentene)/titanium dioxide nanotubes. Titanium dioxide nanotubes were functionalized for better dispersion in the polymer matrix and correlation with polymer chains. Pure membranes with 2 wt% made of polymer and combined membranes with 0.5, 1 and 2 wt% were gathered. Membranes were made as a result of the solvent evaporation process. The permeability rate of pure gases including nitrogen, oxygen, methane and carbon dioxide was considered in gas separation system. A scanning electron microscope was used to identify the structure of membranes and study the Fourier transform infrared spectra and X-ray diffraction. The analysis of images revealed a homogenous and proper distribution of the nanoparticles for all membranes. Also, agglomeration occurred in 2 wt% of titanium dioxide. The properties of membrane's permeability were improved through inspecting the effects of increasing the percentage of composition of the nanoparticles, simultaneous enhancement in permeability values and selectivity of all gases at different pressures. In addition, pressure changes indicated simultaneous growth in permeability values and gas selectivity up to 6 bar with respect to pure membranes. In fact, selectivity is also reduced for the sake of some agglomeration in membranes of 2 wt% nanoparticle, while increasing the permeability is enhanced due to the membranes of 2 wt% nanoparticle. [ABSTRACT FROM AUTHOR]

Asphaltenes pose several problems in petroleum industry. Therefore, finding new reliable methods and materials to address this issue is of vital importance. In this study, asphaltene adsorption onto two mineral adsorbents, lightweight expanded clay aggregates (LECA) and Perlite, in the presence and the absence of two different inhibitors (Dodecilebenzenesulfonic acid or DBSA and coconutdiethanolamide or CDEA) was studied. The results were fitted to three different adsorption isotherms to understand the nature of the adsorptions. Overall, in the absence of inhibitors, Perlite adsorbed more asphaltenes, while the asphaltene adsorption per surface area for LECA was greater than that of Perlite. However, in low asphaltene concentrations, the adsorption is independent of the adsorbent type, as the adsorption behavior of the adsorbents starts to differ in higher asphaltene concentrations. The adsorption data were not fitted to the Henry’s isotherm, while they were successfully fitted to the Freundlich and the Langmuir isotherms. It was concluded that the adsorption process onto both adsorbents were heterogeneous and monolayer while the process for Perlite was more heterogeneous. Given the satisfactory adsorption isotherm parameters for both LECA and Perlite, it is concluded that both LECA and Perlite are good asphaltene adsorbents. Moreover, it was shown that increasing the inhibitor to asphaltene ratio not always causes a reduction in asphaltene adsorption. In fact, there is an optimum ratio (2:1) for both inhibitors where the least asphatene is adsorbed. In both cases of the adsorbents, DBSA had a better performance in lowering the adsorption of asphaltene on the surface of the adsorbents. [ABSTRACT FROM AUTHOR]

Searching for computational approaches for determination of the minimum miscibility pressure (MMP) is highly requested during the miscible gas injection process. New models, namely, the stochastic gradient boosting (SGB) algorithm and two distinct hybrid artificial neural network (ANN) models were used to predict CO2MMP as a function of reservoir temperature, mole percent of volatile oil components, mole percent of intermediate oil components, molecular weight of pentane‐plus fraction in the oil phase, mole percentage of CO2 in injected gas, volatile components, and intermediate components in the injected gas based on 144 published data points. The SGB model was found to provide the better performance. The reservoir temperature turned out to be the most important factor. [ABSTRACT FROM AUTHOR]

Solubility is one of the most indispensable physicochemical properties determining the compatibility of components of a blending system. Research has been focused on the solubility of carbon dioxide in polymers as a significant application of green chemistry. To replace costly and time‐consuming experiments, a novel solubility prediction model based on a decision tree, called the stochastic gradient boosting algorithm, was proposed to predict CO2 solubility in 13 different polymers, based on 515 published experimental data lines. The results indicate that the proposed ensemble model is an effective method for predicting the CO2 solubility in various polymers, with highly satisfactory performance and high efficiency. It produces more accurate outputs than other methods such as machine learning schemes and an equation of state approach. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Despite previous researches on ion-engineered waterflooding (IEWF), its underlying mechanisms are not fully understood, particularly in presence of additives, like surfactants. This paper concerned with the contribution of Ca2+, Mg2+, S O 4 2- and Na+ into altering wettability of oil-wet carbonate minerals towards water preferred state. As a mechanistic study, an experiment workflow was conducted to probe the impact of ions' concentrations in SW, either with or without sodium dodecylbenzene sulfonate (SDBS) which is an anionic surfactant. At first, contact angle (CA) measurement was carried out to evaluate the degree of wettability reversal upon treating the oil-aged calcite slabs with desired ionic composition. Further, to evaluate dynamic response of wettability alteration, the core-flood operation was carried out by successive injection of solutions selected by static CA results. In the case of plain SW flooding, i.e., without surfactant, sulfate dominates success of IEWF, without which wettability reversal did not occur. However, at quadrupled concentration, it acts detrimentally. Ca2+ and Mg2+ both showed an increasing trend of wettability improvement versus concentration. Also, Na+ adversely affected the treating process, without which calcite surface became a neutral state. Oil recoveries observed by core-flood experiment were in accordance with primitive CA measurements. Having SDBS generally improved the wetting reversal, while with a distinct response against salinity. The synergic actions of individual ions and SDBS molecules were interpreted via three interaction modes: surface adsorption of surfactant by increasing Na+, hydrophobic interaction of SDBS's tail with adsorbed carboxylates and releasing those compounds, and reduction of monomeric surfactants by forming strong ion-pairs with divalent cations, particularly Mg2+. The effect of IFT reduction and wettability modification of SDS was distinguished via a special flooding scenario, where latter proved to be significant and kinetically controlled. [ABSTRACT FROM AUTHOR]

The solubility of acidic components at various temperatures and pressures in ionic liquids (ILs) is one of the decisive property needed for the appraisal of ILs as potential substitutes for alkanolamines in industrial natural gas sweetening processes, therefore its modeling encompasses scientific and commercial interest. To that end, in the present work, an advanced machine learning approach called stochastic gradient boosting ( SGB ) tree technique is employed in the calculation of hydrogen sulfide (H 2 S) solubility in 11 different ILs within the (303.15 to 363.15) K temperature and (0.0608 to 2.0168) MPa pressure range as a function of critical temperature, critical pressure and acentric factor of ILs accompanied with operational temperature and pressure. A collection of 465 experimental data points were assembled from the literatures. The statistical parameters including correlation coefficient (R) of 0.999543 and mean relative absolute error (MRAE), 0.022198, of the results form dataset values exhibit the high precision of the applied method. Furthermore, the prediction competence of the SGB model has been compared to two well-known equation of states ( EOS ) as well as Genetic Expression Programming ( GEP ) and least squares support vector machine ( LSSVM ) models. According to the results of comparative studies, it was found that the SGB model is more robust, reliable and efficient than other existing techniques for improved analysis and design of natural gas sweetening process. [ABSTRACT FROM AUTHOR]

The efficiency of gas separation by mixed-matrix membranes (MMMs) derived from poly(4-methyl-1-pentene) (PMP) filled by zinc oxide nanoparticles is investigated. The membranes are prepared by the solvent evaporation method. The zinc oxide nanoparticles are loaded at different weight percentages. The results reveal that adding zinc oxide nanoparticles at all loading percentages of the nanoparticles increases the selectivity of all gas pairs such as O2/N2, CO2/CH4, and CO2/N2. Furthermore, the CO2 permeability in PMP-zinc oxide MMMs was significantly improved when increasing the feed pressure. [ABSTRACT FROM AUTHOR]

To mitigate wax deposition, having an accurate model is of vital importance. In this study, an artificial neural network (ANN), with 19 and 8 neurons at its hidden layers, was developed to predict wax deposition thickness (WDT) during single-phase turbulent flow of oil. The proposed ANN takes wax content, Reynolds number, oil/pipeline temperature, and deposition time as input arguments. Predicted WDT by ANN was in close agreement with experimental data, with AARD% and RMS of 4.5369 and 0.011, respectively. Prediction of ANN was compared with that of adaptive neuro-fuzzy inference system (ANFIS). Results demonstrate superiority of ANN over ANFIS. [ABSTRACT FROM AUTHOR]

Asphaltene precipitation is a major assurance problem posing significant technical and economic loss on petroleum industry. To tackle this issue, various treatments have been proposed and applied by industry. Amongst, inhibiting or retarding the asphaltene precipitation has been understood as the most efficient approach. In this regard, blending crude oil with chemical additives could appreciably heighten its stability. Surfactants, owing to amphiphilic nature, could keep asphaltene dissolved in crude oil by precluding self-tendency of those particles to making agglomerates. Despite importance of this subject, there is still lack of sufficient experimental data to evaluate effectiveness of different inhibitors for oils of various regions, in particular Iran. Therefore, our research group made effort to investigate performance of different oil soluble additives for enhancing stability of asphaltene in Iranian crude oil through measuring onset of asphaltene precipitation using viscometry method. This study presents complementary data to our previous works as well as providing a deep discussion to compare influence of toluene, linear and branched dodecyl benzene sulfonic acid (DBSA) and cocamide diethanolamine (CDEA). It was realized that inhibition characteristic is driven by the synergy between strength of polar head and tail length of chemicals, as well as inhibitor concentration in the oil phase. In this respect, this work suggests the following priority order for selecting inhibitors: Linear-DBSA > CDEA > Branched-DBSA > Toluene. In the second part of this work, the measured onset points were predicted through coupling Peng-Robison (PR) with Dehaghani association equation of state (DA-EOS). The applied model gave successful prediction via taking asphaltene self-association and asphaltene-inhibitor cross association into account. [ABSTRACT FROM AUTHOR]

Asphaltene precipitation is introduced as a seriously problematic issue in the petroleum reservoirs that causes filling porosity of rocks and reduction of oil production. Hence, estimating the amount of precipitated asphaltene has huge importance in preventing the deposition of asphaltene. The present study was done to estimate the precipitated asphaltene as a function of temperature, dilution ratio, and molecular weight of different n-alkanes using adaptive neuro-fuzzy inference system (ANFIS). Moreover, another new scaling model was also developed to compare with the ANFIS model. In addition, these two developed models have been compared with previously developed correlations. The obtained values of R2for the ANFIS and scaling models were 0.9912 and 0.9862, respectively. These tools are simple to use and can be used as an accurate approximation of the precipitated asphaltene as a function of temperature, dilution ratio, and molecular weight of different n-alkanes. [ABSTRACT FROM PUBLISHER]

Formation of hydrate crystal particles has been one of the major difficulties facing gas industry in the generation, transmission, and processing that causes blockage of pipelines and equipment resulting in decreases of level of safety and immunity Which necessitating proper methods to prevent hydrate formation. One of the most common treatments are injection of chemical inhibitors. Keeping excessive cost of hydrate remediation and inhibition in mind, using a reliable predictive model is the key step of designing a natural gas transmission operation. In this paper the van der Waals and Platteeuw (vdW-P) model was coupled with Dehaghani et al.'s association equation of state (DA-EOS) for prediction of equilibrium temperature of methane hydrate in presence of methanol (MeOH), ethanol (EtOH), and mono-ethylene glycol (MEG) as thermodynamic inhibitors. To increase the calculation accuracy, the mole fraction of components in the liquid and gas phases were obtained using the results of flash algorithm calculations. In addition, effect of gas dissolution in aqueous phase was considered by Henry's law and water activity coefficient calculation was performed based on φ- φ approach. Additionally, the binary components interaction coefficients in the system, was considered as a linear function of temperature. To evaluate the capability of DA-EOS, the prediction of methane hydrate phase behavior in presence and absence of inhibitors was compared with the experimental data and also the prediction of Peng-Robinson EOS (PR-EOS). In addition, a comparison was made between DA-EOS and Elliott–Suresh–Donohue uation of State (ESD-EOS) to gain insight of performance of present model. The prediction of DA-EOS and ESD-EOS was close to each other. DA-EOS proved to be effective in representing self-association between water and cross-association between water-inhibitor components in the case of hydrate solution. Also, it was concluded that performance of vdW-P model strongly depends on reliability of EOS used for calculation of fugacity coefficient. [ABSTRACT FROM AUTHOR]

• Hybridge of the microwave the smart water drastically improves the water-wetness. • The mechanism of the wettability alteration is not limited to the thermal effects. • The Van der Waals and electrostatic forces are weakened during microwave radiation. • Increasing ion collision, caused by the electric field, leads to more oil recovery. This research aims to investigate the efficiency of a new hybrid method of smart water imbibition assisted with microwave (MW) radiation. Some experiments including the contact angle measurement, attenuated total reflectance (ATR), zeta potential evaluation, oil viscosity measurement, and smart water imbibition were studied to find the effect of the MW radiation on the performance of the smart water imbibition. To capture the controlling mechanisms, it was essential to sustain the temperature in some of the MW treatments. Hence, the rock sections were treated by two methods of dry (MW treating the sections without immersion in the brine water) and immersed (MW treating the sections when they are immersed in the brine water) treatments. It was shown that the contact angle of an aged rock section could be reduced from 170° at the initial condition to almost 37° due to treating by smart water and the MW radiation. Divalent cations of Mg2+ and SO 4 2- were discovered to be more efficient in the wettability improvement than Ca2+, and this fact was discussed in detail from thermodynamic and kinetic points of view. Also, it was found that the MW thermal effect is not the only reason for the wettability improvement and organic compound desorption, but also the MW treatment could destabilize the organic compounds on the rock surface through generating oscillating electric fields. This fact was confirmed by the results of the immersed MW treatment, where the contact angle reduction was found to be almost as efficient as the dry MW treatment. Based on the ATR spectrums, the MW radiation can desorb the polar and non-polar compounds in two different mechanisms of thermal desorption and destabilization caused by oscillating electric fields. Furthermore, it was shown that the oil viscosity was reduced due to temperature rising caused by the microwave treatment, but when the temperature of the oil sample reduced to the room temperature, the viscosity reduction was not observed. The oil viscosity, after the treatment for 2 min, with the radiation power of 20, 40, 60, 80, and 100 maximum power increased to 52.5, 53.1, 55.5, 54.2, and 53.1 cp, respectively. Finally, it was shown that the oil recovery was increased 9% during the MW radiation for 16 min in the smart water imbibition test. Based on the observed results in this research, it is concluded that the hybrid of smart water imbibition assisted with MW radiation could be considered as a novel EOR method resulting in more oil recovery. [ABSTRACT FROM AUTHOR]

In this study, municipal polymer wastes that were no longer recyclable and were previously buried underground according to the usual municipal waste management program were converted to liquid fuel by catalytic pyrolysis technique. In the first step, zeolite Y catalyst was used to improve the quality of liquid fuel. In the second step, MIL-53 (Cu) was incorporated onto zeolite and pyrolyzed in nitrogen in the atmosphere. The analysis shows that clusters of carbon nanopores with a copper core, and its oxides were deposited on the zeolite. For both types of catalysts, the crystallization time of zeolite was investigated, and it was found that this leads to the synthesis of samples with different percentages of crystallinity. For each test, the liquid fuel produced was divided into four cuts: gasoline, jet fuel, diesel, and wax. The test results in a fixed bed reactor for every twelve samples of catalyst and their effect on the efficiency of different sections of liquid fuel show a significant improvement in the desired product. The properties and morphology of the catalysts were investigated. It was found that at 400 °C and a crystallization time of 18 h for support with 76.62% crystallinity, gasoline production efficiency will be 37.00%. At 500 °C and low crystallinity, the tendency of reaction to produce jet fuel with a maximum efficiency of 48.64%. Furthermore, the physical properties of each cut of liquid fuel and their comparison with the reported values indicating the appropriate qualities of the produced fuel were evaluated. In the optimal state, the octane number of the produced gasoline is 93.5 and its pour point is 41 °C. Also, a jet fuel with an octane number of 43.2 and a flashpoint of 69 °C has been obtained. In the case of diesel, the octane number and its viscosity have reached 46 and 2.407 cp, respectively. Examining the results obtained from GC MS, it was found that the zeolite catalyst modified by Diels Alder mechanism and branching will improve the quality of liquid fuel and on the other hand, will cause the cracking of the wax compounds and reduce their percentage in product analysis. [ABSTRACT FROM AUTHOR]

Condensate formation near the wellbore is considered as one of the challenging problems affecting the production from a gas reservoir. Two types of mechanical and electromagnetic (EM) waves were implemented to remove this production barrier. Two core plugs with different mechanical and electrical properties were saturated with condensate fluid belonging to a gas field in the south of Iran and then subjected to the ultrasonic (US) waves with two frequencies of 37 and 80 kHz at different powers and time durations. Besides, the saturated plugs were exposed to the microwaves (MWs) with different powers at an identical wave frequency of 2.45 GHz. The experimental results showed that the ultimate removal factors from the plugs using the US and MW treatments varied at different conditions and mediums. The condensate removal efficiency from the plug (2) was higher than the plug (1) at both treatments. This could be explained by the mechanical, petrophysical, and electrical properties of both plugs. The acoustic impedance of the plug (2) was obtained 2.6 folds of the plug (1). More acoustic impedance gives rise to more local pressure disturbance and more external force to overcome the liquid surface tension. The ultimate condensate removals from the plug (2) using the US treatment at the highest powers were obtained almost 7% and 31% at the frequencies of 37 kHz and 80 kHz, respectively. Similarly, the ultimate condensate removal of the plug (1) at the highest power was obtained 2.4% and 16.9% at the frequencies of 37 kHz and 80 kHz, respectively. The ultimate condensate removals from the plugs (1) and (2) were 19% and 100%, respectively, in the MW treatment at the highest power level. As it was obvious from the temperature profile of the plugs, the dominant mechanism of the MW treatment for condensate removal was the dissipation of the EM wave energy. The composition of the plugs showed that the dielectric constants were approximately equal. Hence, minerals of both rocks had the same electrical behavior. Higher porosity of the plug (1), which resulted in more saturation with lower dielectric fluids, gave rise to a reduction in average dielectric constant. In other words, less average dielectric constant resulted in less temperature raising. • The microwave and ultrasonic treatments depend on the dielectric constant ad acoustic impedance, respectively. • The primary mechanism of the condensate removal during the ultrasonic treatment is inducing artificial pressure disturbance. • The primary mechanism of the condensate removal during the microwave treatment is based on the thermal loss of the microwaves. • It is important to remove all of the liquid condensates because both of ultrasonic and microwave treatments make the remained condensates heavier. [ABSTRACT FROM AUTHOR]

Injection of low-salinity or smart water into the reservoir is one of the most common EOR techniques. This technique leads to more oil recovery in comparison to reservoir water and seawater injection. Several mechanisms explain the reasons for this increased recovery level, the most important of which is the wettability alteration towards water-wet conditions. However, in recent years, further mechanisms have been added to the previous ones as the main or complementary mechanism. One of these newly added mechanisms is the performance of oil as a semi-permeable membrane between connate and low-salinity waters. According to this mechanism, water molecules move from low-salinity water through oil to connate water due to the difference in their osmotic pressure (difference in chemical potential), which works as the driving force, until the system moves toward equilibrium in concentration. Introducing water molecules into connate water causes the swelling of connate water, and eventually moves the oil towards the pore throats. In this study, experiments have been performed on capillary tubes, while ignoring the effect of fluid-rock interactions to investigate the proposed theory. Experimental results confirmed the role of osmotic theory. Furthermore, a decrease in the salinity of the low-salinity water causes the oil-droplets' displacement to increase, whereas further reductions in the salinity of the injected water cause lower displacements. Therefore, there is an optimum value of low-salinity water concentration to obtain the highest possible oil drop displacement. The optimum values for the tested samples in this study were about 5000–10000 ppm. Additionally, it was found that among all of the essential seawater salts, potassium chloride leads to the highest oil drop displacement; and among oil samples, heptane showed better membrane-like performance in comparison to toluene and crude oil. • Hydrocarbons are a membrane for water molecules and pass them from low-salinity to high-salinity water. • In lower salinities, reducing the salinity of the low-salinity water can reduce the membrane performance of the oil. • Different hydrocarbon materials exhibit various membrane performances, related to their viscosities. • Among the important salts in the seawater, KCl is a far better membrane for oils and lead to the most oil displacement. [ABSTRACT FROM AUTHOR]

Pyrolysis of plastics is an economical method to recover valuable fuels from waste sources. In this study, the response surface methodology is adopted to model the behavior for the pyrolysis of high-density polyethylene (HDPE). The three operating parameters of temperature in the range of 415 to 585 ° C , feed density in a window between 959 and 967 kg / m 3 and reactor loading range from 23 to 57% were selected as the main variables. Using the thermogravimetric analysis (TGA) study for different heat transfer rates, the range at which the feed is fully converted was determined, thus ensuring that the correct operating temperature range was selected. By drawing difference thermogravimetry (DTG) curves and using a dynamic model, the activation energy for converting heavy and light feeds was determined to be 300.984 and 273.57 kJ / mol , respectively. Analysis of the experimental results using the (Central Composite Design) CCD method shows the ease of pyrolysis of light feed, which is agreed upon with less activation energy. As the main goal of this study, the effect of parameters on the liquid fuel production was investigated, and it was turned out that under optimum conditions, the amount of liquid fuel production will be 95.3%. For the optimal conditions, a temperature of 500 ° C , feed density is 963 kg / m 3 and reactor loading rate of 40% were determined. Analysis of the exhaust gases also showed that propylene and ethane are the most abundant components of this phase. Furthermore, with the help of analysis of variance, the proposed model to produce liquid fuel and gas yield was evaluated as a significant and the accurate model. Finally, under the optimized conditions, by using a new MIL-53 (Cu) derived @ Zeolite Y catalyst, the percentage of heavy compounds in the fuel was meaningfully reduced, and at the same time, the octane number of the gasoline produced was considerably improved. Based on the energy considerations, it was calculated that the recovery of energy from combustion as well as the sensible energy of the exhaust gases from the reactor, leads to significant savings in total energy consumption to produce each gram of liquid fuel. [Display omitted] • Liquid fuels have been produced via pyrolysis of plastic wastes. • Response surface methodology has been adopted to model the behavior of the process. • Three parameters of polymer density, temperature and reactor loading have been studied for the optimization. • Using of MIL-53 (Cu) derived @ Y zeolite catalyst has been reduced wax formation from 47.82 to 2.59%. • Significant amount of energy can be recovered from the process using heat recovery systems. [ABSTRACT FROM AUTHOR]

Seawater pollution from various sources such as industrial effluents, ship washing at sea, and oil spills harm humans and the marine environment. Therefore, finding ways to eliminate this pollution is crucial. This study successfully modified a polyurethane sponge through a simple dip-coating method with functionalized graphene oxide incorporating octadecylamine and oleic acid, resulting in a hydrophobic sponge capable of absorbing crude oil and various organic solvents. Characterization analyses confirmed the synthesis. The absorption capacity of the modified sponges was examined, for example, the PU sponge has absorbed 4 g/g engine oil, while the modified GO-ODA-PU sponge has increased its absorption to 36 g/g. The GO-ODA-PU sponge demonstrated great reusability compared to the GO-OA-PU sponge owing to the strong covalent bond formed between GO and ODA, which is superior to the weak hydrogen bond formed between GO and OA. The absorption capacity of the GO-OA-PU sponge decreased by 30%. The contact angle test showed that GO-ODA-PU and GO-OA-PU sponges had contact angles of 131° and 115°, respectively. Additionally, the GO-ODA-PU sponge performed optimally for semi-polar solvents in the solubility parameter range of 18–19, with its absorption capacity reaching its maximum value. The amount of oil recycling is even possible up to 98%. [Display omitted] • Modified polyurethane sponge is an absorbent of oil pollution. • The amount of recycled oil in the sponge has been studied. • The property of the solubility parameter has been introduced. • The effect of bond type on absorption capacity has been investigated. [ABSTRACT FROM AUTHOR]