Water-oil Ratio Research Articles

Construction of 3D printable Pickering emulsion gels using complexes of fiber polysaccharide-protein extracted from Haematococcus pluvialis residues and gelatin for fat replacer

Structural fat replacers that can meet the requirements of various forms of reduced-fat foods are essential for the application of fat replacement, and emulsion gels emerge as a potential alternative for fat replacers. In this study, fiber polysaccharide-protein extracted from Haematococcus pluvialis residues (FPHRs) formed FPHRs-Gelatin complexes with gelatin. Fourier transformed infrared spectroscopy confirmed the formation of hydrogen bonds between FPHRs and gelatin, the secondary structure order of the protein was enhanced. Three-phase contact angle determination showed that the contact angle of FPHRs-Gelatin complexes was 104°–114°. By exploring the effect of FPHRs concentration, gelatin concentration, and oil-water ratio on the emulsion gels, the Pickering emulsion gels were formed when the FPHRs and gelatin concentration were 2 wt% and 3 wt%, respectively. What's more, these emulsion gels had shear thinning phenomenon, low frequency dependence as well as excellent thixotropy when the oil-water ratio was 0.6, which indicated that they had strong structural support and great recovery capacity to be used as 3D printed materials. The 3D objects printed by the FPHRs-Gelatin complexes emulsion gels had superior print resolution and shape fidelity. This study provides a new type of emulsion gel with structure that can be used as an ideal fat replacer in food processing, the construction of a new 3D emulsion gel material is of great significance for broadening the applications of gelatin-based gels and microalgal food.

Isotherm modelling and optimization of oil layer removal from surface water by organic acid activated plantain peels fiber

This research aimed to optimize and model the adsorption process of oil layer removal using activated plantain peels fiber (PPF), a biomass-based material. The adsorbent was activated by thermal and esterification methods using human and environmentally friendly organic acid. Effects of process parameters were examined by one factor at a time (OFAT) batch adsorption studies, revealing optimal conditions for oil removal. Also, RSM, ANN and ANFIS were used to adequately predict the oil removal with correlation coefficient > 0.98. RSM modelling revealed the best conditions as 90 °C, 0.2 mg/l, 1.5 g, 6 and 75 mins, for temperature, oil–water ratio, adsorbent dosage, pH and contact time respectively. Under these simulated conditions, the predicted oil removal was 96.88 %, which was experimentally validated as 97.44 %. Thermodynamic studies revealed the activation energy, change in enthalpy and change in entropy for irreversible pseudo-first order and pseudo-second order model as (15.82, 24.17, −0.614 KJ/mols) and (33.21,40.31, −0.106 KJ/mols) respectively, indicating non-spontaneous process; while modeling studies revealed that the adsorption process was highly matched to Langmuir’s isotherm, with maximum adsorption capacity of 50.34 mg/g. At the end of the overall statistical modelling, ANFIS performed marginally better than the ANN and RSM. It can be concluded from these results that our biomass-based material is an efficient, economically viable and sustainable adsorbent for oil removal, and has potentials for commercialization since the process of adsorption highly matched with standard models, and its capacity or percentage oil removal also compares favorably to that of commercially available adsorbents.

Pickering Emulsions Synergistically Stabilized by Aliphatic Primary Amines and Silica Nanoparticles.

Innovation in emulsion compositions is necessary to enrich emulsion formulations and applications. Herein, Pickering emulsions were prepared using silica nanoparticles and aliphatic primary amines with an oil-water ratio of 1:1 (v/v). Contact angle experiments revealed that the in situ hydrophobization of nanoparticles was caused by the surface adsorption of amine molecules. Notably, the interactions between amine compounds and the surface of silica nanoparticles were electrostatic attractions and mutual hydrogen bonding. The existence of hydrogen bonds was further confirmed by demulsification experiments using a chaotropic agent DMF and increasing temperatures. The hydrophobicity of silica nanoparticles can be effectively improved using most commercially available aliphatic primary amines such as n-hexylamine, n-octylamine, n-decylamine, dodecylamine, and tetradecylamine. The minimum concentrations of the aforementioned amines necessary for stabilizing the emulsions with 0.3 wt % silica nanoparticles are 3, 0.6, 0.3, 0.06, and 0.03 mM, respectively, decreasing significantly with increasing alkyl chain length. With the increase of the amine concentrations, the hydrophobicity of silica particles monotonically increased and finally resulted in the inversion of emulsions. The amine concentrations for emulsion phase inversion were 150, 40, 30, 20, and 20 mM, respectively, in the presence of 0.3 wt % silica nanoparticles. In this work, silica nanoparticles were hydrophobized using aliphatic primary amines. The composite stabilizers developed are useful for developing novel stimuli-responsive Pickering emulsions, while the synergistic effects introduced herein are also helpful in expanding the hydrophobization methods available for nanoparticles.

A Study on Generation and Feasibility of Supercritical Multi-Thermal Fluid

Supercritical multi-thermal fluid is an emerging and efficient heat carrier for thermal recovery of heavy oil, but the generation of supercritical multi-thermal fluid and its feasibility in thermal recovery are rarely discussed. In this paper, generation and flooding experiments of supercritical multi-thermal fluid were carried out, respectively, for the generation and feasibility of supercritical multi-thermal fluid. During the experiment, the temperature and pressure in the reactor and sand-pack were monitored and recorded, the fluid generated by the reaction was analyzed by chromatography, and enthalpy of the reaction product and displacement efficiency were calculated, respectively. The experimental results showed that the change in temperature and pressure in the reactor could be roughly divided into three stages in the generation process of supercritical multi-thermal fluid. The higher the proportion of oil in the reactant, the higher the maximum temperature in the reactor. When the proportion of oil and water in the reactant was constant, the temperature rise in the reactor was basically the same under different initial temperature and pressure conditions. Compared with the initial temperature and pressure, the oil–water ratio of the reactants had a significant effect on the generated supercritical multi-thermal fluid. The higher the proportion of oil, the more gas that was generated in the supercritical multi-thermal fluid, and the lower the specific enthalpy of the thermal fluid. Under the same proportion of oil and water, the gas–water mass ratio of the supercritical multi-thermal fluid generated by the reaction of crude oil was lower, and the specific enthalpy was higher. Through this study, it was found that supercritical multi-thermal fluid with a low gas–water mass ratio had higher oil displacement efficiency, higher early oil recovery rate, a larger supercritical area formed in the oil layer, and later channeling. The results of this study show that the optimal gas–water mass ratio of supercritical multi-thermal fluid was about 1, under which the oil displacement efficiency and supercritical area in the oil layer reached the maximum. Correspondingly, the optimal proportion of oil in the reactant when generating supercritical multi-component thermal fluid was about 10%. In oilfield applications, because the gas–water ratio in supercritical multi-component thermal fluid has a significant impact on oil displacement efficiency, the optimization of supercritical multi-thermal fluid should not only consider the generation process but also consider the oil displacement effect of the thermal fluid. The findings of this study could improve our understanding of the characteristics of generating supercritical multi-thermal fluid and the feasibility of supercritical multi-thermal fluid generated under different conditions in the oil displacement process. This research is of great significance for field applications of supercritical multi-thermal fluid.

Horseradish peroxidase-catalyzed synthesis of high-quality polyaniline in Good’s buffer ionic liquid-buffered H2O/AOT/isooctane bicontinuous microemulsion

Here, a functionalized organic salt composed of [Nk,k,k,k]+ (k = 1–4) and [MES]- (2-(N-morpholino)ethanesulfonate), i.e., Good’s buffer ionic liquid with self-buffering and biocompatible properties, was chosen as electrolyte as well as buffer to construct a H2O/AOT/isooctane bicontinuous microemulsion for enzymatic synthesis of polyaniline (PANI). Studies on the effects of the functionalized organic salt on the phase behavior indicate that [Nk,k,k,k][MES] can tune the phase inversion temperature of AOT-stabilized oil-water microemulsion system through changing the cationic alkyl chain length, exhibiting the properties of both inorganic salt and co-alcohol. More interestingly, the stability of horseradish peroxidase (HRP) solubilized in the H2O(0.1 M [N1,1,1,1][MES], pH = 4.5)/AOT/isooctane bicontinuous microemulsion is much better than that formulated with mixed surfactants AOT/SB-12 and inorganic salt. Studies on the HRP-catalyzed oxidative polymerization of aniline in the present bicontinuous microemulsion indicates that at low surfactant content and high oil-water ratio, the present microemulsion resulted in a PANI with better conductivity than the counterpart reported elsewhere. This work is of guiding significance for constructing a less-component and enzyme-compatible bicontinuous microemulsion for template-assisted biopolymerization.

Fabrication and Characterization of W/O/W Emulgels by Sipunculus nudus Salt-Soluble Proteins: Co-Encapsulation of Vitamin C and β-Carotene.

W/O/W emulsions can be used to encapsulate both hydrophobic and hydrophilic bioactive as nutritional products. However, studies on protein stabilized gel-like W/O/W emulsions have rarely been reported, compared to the liquid state multiple emulsions. The purpose of this study was to investigate the effect of different oil–water ratios on the stability of W/O/W emulgels fabricated with salt-soluble proteins (SSPs) of Sipunculus nudus. The physical stability, structural characteristics, rheological properties, and encapsulation stability of vitamin C and β-carotene of double emulgels were investigated. The addition of W/O primary emulsion was determined to be 10% after the characterization of the morphology of double emulsion. The results of microstructure and rheological properties showed that the stability of W/O/W emulgels increased with the increasing concentration of SSPs. Additionally, the encapsulation efficiency of vitamin C and β-carotene were more than 87%, and 99%, respectively, and still could maintain around 50% retention of the antioxidant capacity after storage for 28 days at 4 °C. The aforementioned findings demonstrate that stable W/O/W emulgels are a viable option for active ingredients with an improvement in shelf stability and protection of functional activity.

Modelling and optimization of crude oil removal from surface water via organic acid functionalized biomass using machine learning approach

Banana peel fiber adsorbent (BPF) with well-arranged substructure of pores was fabricated via esterification reaction with organic acid and biomass. The emerged adsorbent (BPF) was employed in taking away crude oil from water surface. Three machine learning tools such as RSM, ANN and ANFIS was employed for the modelling and optimization of the process. From results, the optimal oil layer removal of 98.2% was achieved at oil water ratio of 0.2 g /100 cm 3 . For now, BPF displayed high adsorptive prospect at a very low pH of 4 with 96.8% oil removal. On the other hand, the activation energy, enthalpy change and entropy change of the system are (18.56, 25.44, −0.751 KJ/mols) and (25.77, 29.16, −0.813 KJ/mols) designating a non-spontaneous system. The process of removal by BPF really matched the Langmuir isotherm model as proved by statistical error analysis with highest adsorption capacity of 49.33 mg/g as shown through equilibrium modeling. RSM displayed the optimum conditions of the key variables such as temperature, oil concentration, adsorbent dosage, pH and time as 100 °C, 0.2 g/100 cm 3 , 1.5 g, 2 and 75 mins, respectively. Analysis of the three generic algorithm indicated significant oil removal prediction with quite remarkably similar coefficient of correlation of 0.999. Additional statistical analysis suggested that RSM was marginally better than ANN and ANFIS for the modelling of crude oil removal via esterified banana peels fiber.

Sustainable preparation of surface functionalized cellulose nanocrystals and their application for Pickering emulsions

Herein, a highly efficient and sustainable approach, namely HCl-catalyzed para-toluene sulfonic acid/Formic acid (p-TsOH/FA) hydrolysis was reported to produce surface functionalized cellulose nanocrystals (CNCs). The optimized CNCs showed a high yield (79.6 %), high crystallinity (70.6 %) and high thermal stability (maximal weight loss temperature around 350 °C). In addition, the as-prepared CNCs possess excellent ability to stabilize oil-water due to the introduction of functional formyl groups, which could be promising stabilizers for Pickering emulsions (PEs). At a fixed oil-water ratio (2:8, v:v), the CNCs with the concentration of 0.5 wt% to 2.0 wt% could stabilize peanut oil to make PEs, and the emulsion droplets were <5 μm in diameter. In addition, the stability of the PEs at different temperature, pH, ionic strength, and long storage time were studied. The results indicated that the obtained CNCs could be sustainable and superior stabilizers for PEs.

An Environmentally Friendly Inverse Microemulsion Method to Synthesize Polyacrylamide.

Polyacrylamide (PAM) was prepared by a new method of inverse microemulsion polymerization, with (NH4)2S2O8-Na2SO3 as initiator and liquid paraffin/Span80-Op10/AM-H2O-NaAc as polymerization system in this paper. The effects of initiator dosage, emulsifier dosage, monomer concentration, oil–water ratio, and temperature on molecular weight, electrical conductivity, particle size distribution, and monomer conversion were studied as well. The results indicate that that the more stable Polyacrylamide (PAM) polymer was prepared under the conditions of initiator dosage of 0.4~0.5%, emulsifier dosage of 55~60%, temperature of 40~45 °C, hydrophile–lipophile balance (HLB) value of 8.0~8.2, and NaAc concentration of 3%.

Analysis of the stability of oil-based drilling muds by electrical stability measurements as a function of oil-water ratio, weighting material and lubricant concentrations

Oil-based muds (OBM) used in drilling processes are complex fluids formed by a water-in-oil emulsion stabilized by emulsifiers. Measurements of the electrical stability (ES) are considered directly indicators of mud stability, together with yield point (YP), and fluid loss (FL). In this work, it was studied the effect of oil-water ratio (OWR) in the mud stability using the ES, YP and FL data. To analyze those individuals and paired effects, it was applied a Central Composite Rotational Design (CCRD) planning with three replicates at the central point plus eight and six factorial and axial points. Results showed that all studied factors presented a high influence on the ES results. Additional measurements of rheological properties and fluid loss were carried out to verify and analyze the impact of the composition on the main drilling mud properties. Statistical analysis was also performed to clarify the role of the different factors investigated in this research. The authors observed that several drilling mud compositions are not suitable for the oilfield application, and, by an optimization procedure, an optimal formulation has been proposed.

Study on graphene-based emulsions as oil displacement agent

Abstract In this study, graphene oxide (GO) was prepared by the improved Hummers method, and a synergistically stabilized emulsion of GO and emulsifier was formulated. The best emulsion formula obtained by Response Surface Methodology consists of 1.39‰ GO, and 2.92‰ OP-10; the water-oil ratio is 4:6, achieving an emulsion index of 92.83%. The emulsion still maintained good stability under high temperature and high salt conditions, meeting the environmental requirements of medium and low permeability reservoirs. For injected water flooding, emulsion flooding could increase the oil recovery by 15.41%.

Development of an effective completion schedule for a petroleum reservoir with strong aquifer to control water production

sA reasonable solution, to deal with oil field water problem, is to minimize the amount of water associated with oil production using effective completion lengths. This work presents an effective method to optimize wells’ completion lengths in an oil reservoir with a strong aquifer. The suggested technique is formulated as a constrained optimization problem that defines a NPV objective function and a set of existing field/facility constraints. An effective algorithm translates the completion lengths to connections number in the dynamic simulation model. In this approach, a genetic algorithm (GA), an adaptive version of simulated annealing (ASA) and a particle swarm optimization (PSO) hybridized with polytope technique are applied to maximize NPV. A comparison is given for their performances in a strong water-drive reservoir where the combinatorial effects of wells’ completion lengths (decision variables) should be addressed. Optimizing the lengths of completions leads to an increased production period, total oil production, retarding water breakthrough, reducing total water production, and finally increasing ultimate recovery. The results showed that total oil production by GA, ASA and PSO algorithm is increased by 11.0%, 2.40% and 2.22%, respectively, related to the initial case. Total water productions are decreased by GA, 9.82%, by ASA 2.11%, and by PSO 1.82% relative to the initial schedule. The best performance belongs to the GA algorithm. Moreover, the average watercut of all wells is decreased through the optimization process. Besides, based on the numerical simulation, closing the worst connections with high watercut decreases total water production, and improves oil recovery, maximum well productivity, and NPV (oil–water ratio is increased 18.2%). Most connections are placed in the layers where water coning can occur later (considering near-well-bore permeability) and slightly far from full water zone.

Purification mechanism of corona discharge coupled with dimethyl sulfoxide microemulsion for simultaneous desulfurization and denitrification

In this study, a new absorbent dimethyl sulfoxide (DMSO) microemulsion is used, and corona discharge coupled with dimethyl sulfoxide microemulsion is proposed for simultaneous desulfurization and denitrification. This study solves the problem of low efficiency of simultaneous SO2 and NO purification and avoids the problem of easy poisoning of catalysts for simultaneous desulfurization and denitrification. In addition, it makes up for the defects of low efficiency and complex products of desulfurization and denitrification by plasma alone. In this study, the effects of different corona discharge voltages, DMSO microemulsion oil–water ratio and oxygen concentration on the simultaneous removal of SO2 and NO were investigated in detail. The study showed that increasing the voltage and oxygen concentration had a significant promotion effect on the degradation of NO, but the high oxygen concentration would release part of the captured SO2. Under the best experimental conditions, the SO2 removal efficiency could reach 93.4 % and the NO removal efficiency was 84.9 %. In addition, the adsorption energy calculations combined with different initial concentrations and different DMSO microemulsion temperatures illustrate that SO2 and NO react competitively with SO bonds in DMSO and OH bonds in isoamyl alcohol in DMSO microemulsions, with SO2 being preferentially adsorbed. Finally, this study explains in detail the mechanism of simultaneous SO2 and NO degradation, showing that the reactive species generated during corona discharge can excite microemulsions to produce more reactive radicals and active substances to further improve the removal of SO2 and NO.

Shaly detritus embedded epoxy-resin coated proppants

Proppant plays a significant role in the hydraulic fracturing process, which can affect the production of oil and gas wells. Due to the high density and low adhesion force, the settling speed of traditional proppants is fast, which will lead to the blockage of a crack channel. In this study, a proppant with double layer structure is fabricated by coating epoxy-resin and shaly detritus on ceramic proppants for the first time, respectively. The epoxy-resin enables the shaly detritus to be coated on the proppant successfully, which can provide a new method for shaly detritus treatment. The adhesive ability of shaly detritus and epoxy-resin coated proppants (SEPs) is improved by 10.4% under the load force of 500 nN, which prolongs the time for the fracture to close. At the same time, the suspending ability of SEPs is two times higher than the uncoated proppants. Once the guar gum solution concentration is 0.3 wt%, the settling time of SEPs is 36.7% longer than that of the uncoated proppants, which can effectively reduce the settlement of proppants in the crack. In addition, the hydrophobicity of the SEPs is enhanced, which reduces the water-oil ratio of crude oil and increases the liquid conductivity tested by deionized water. In summary, this new proppant is expected to promote the development of unconventional oil and gas resources.

The preparation of linseed oil loaded graphene/polyaniline microcapsule via emulsion template method for self-healing anticorrosion coatings

A novel kind of graphene/polyaniline hybrid microcapsules loaded with self-healing agent (linseed oil, LO) were synthesized by Pickering emulsion template method in this work. In our strategy, graphene oxide (GO) was used as Pickering emulsifier to stabilize emulsion droplet containing aniline and linseed oil. After the polymerization of aniline, graphene/polyaniline microcapsules loaded with linseed oil (LO@GO/PANI) were prepared. By adjusting GO concentration and oil-water ratio, the size of the emulsion droplet and LO@GO/PANI microcapsule can be controlled at about 15–20 µm. The successful synthesis of LO@GO/PANI microcapsules was proved by SEM, FT-IR and TGA. The unique GO/PANI hybrid shell combined the outstanding barrier property of GO and anti-corrosion function of PANI. The solvent resistance results showed that the as-prepared microcapsules possessed stronger resistance to organic solvents. A smart coating with dual functions of anti-corrosion and self-healing was prepared by dispersing the as-prepared LO@GO/PANI microcapsule in waterborne epoxy resin. As the contents of microcapsules was 10 wt%, the scratch of the coating was completely healed after 12 h observed from the microscope images. The electrochemical impedance spectroscopy (EIS) and salt spray test all verified that the incorporation of microcapsules could significantly improve the anti-corrosion performance of the water-borne coatings. After 40 days' immersion, the low frequency modulus of the composite coating was almost 2 orders of magnitude higher than that of pure epoxy coating, and no obvious corrosion product was observed after 500 h salt spray test.

Development of a Generalized Experimental Methodology for Investigating the Role of Steam Quality on Steamflooding Performance

Summary For steamflooding processes, steam quality plays a crucial role because it affects enhanced oil recovery mechanisms and production performance. Many numerical simulations have been performed on the role of steam quality. However, few studies have evaluated the role of steam quality on steamflooding performance by experimental measurements because of the lack of a generalized experimental methodology to accurately generate and measure steam with different qualities under reservoir conditions. The objective of this study is to propose a generalized experimental methodology for investigating the role of steam quality on steamflooding performance. A steam quality controlling box was newly designed and fabricated to generate steam with different qualities, and its reliability was verified by a novel steam quality measurement system together with a developed theoretical method. Then, a series of experiments were conducted by our designed 1D and 2D sandpack models to evaluate the steamflooding performance under different steam qualities. The results showed that the developed methodology could accurately generate and measure steam with different steam qualities. The maximum errors between desired, measured, and calculated steam qualities were 4.39% under the experimental conditions in this study. The steam quality substantially affected the steamflooding performance. A higher steam quality led to a lower water cut, a lower maximum pressure difference between the inlet and outlet of the sandpack model, a lower water/oil ratio (WOR), a lower steam/oil ratio (SOR), a higher oil recovery, and a higher oil production rate. However, there is an optimal value of steam quality from the view of heat efficiency in this study. The oil recoveries of 2D steamflooding experiments increased from 36.30 to 45.02% when the steam quality increased from 0 to 0.8. However, the optimal steam quality of 0.6 had the maximum heat efficiency at 3.16×10−5 kJ−1. This research contributes to a better understanding of steam quality on steamflooding performance and also provides a generalized methodology for other steam injection processes.

Preparation of ethyl cellulose–glycerol tribenzoate microcapsules in CO2/N2‐switchable hydrophilicity solvent and solvent recycling

AbstractIn this article, a novel method of microcapsule preparation was provided, that is, ethyl cellulose–glycerol tribenzoate microcapsule (EGM) was prepared using CO2/N2 switchable hydrophilicity solvent(N, N‐dimethylcyclohexylamine) combined with an emulsion method. Microcapsules were prepared and solvents were recovered by changing the properties of the solvent. The optimum preparation conditions of EGM were the materials ratio of 20%, the oil–water ratio of 4.5:5.5, emulsifier content of 2%, the Span80‐Tween80 ratio of 1:3, and the core‐shell ratio of 1. The morphology of EGM is spherical, and the particle size can be adjusted from 0.01 μm to 90 μm by controlling the agitation speed in the synthesis process. Surprisingly, the average yield(Y[%]) reached 95.36%, the effective content(W[%]) reached 41%, and the encapsulation rate(E[%]) reached 90.66% of EGM. The solvent recovery rate(SR[%]) of the first recovered is 96.37%. Significantly, this method not only provides a new idea for the preparation of microcapsules but also expands the application field of switchable hydrophilicity solvents, which makes it has great potential application value in the field of microcapsule preparation in the future.

Hybrid optimization approach using evolutionary neural network & genetic algorithm in a real-world waterflood development

The hybrid optimization method of using evolutionary neural network (EvoNN) and NSGA-II algorithms is applied in two case studies. The first optimization study is applied in a benchmark model of the Brugge field consisting of 20 oil producers and 10 water injectors. The two objective functions are defined as maximizing short-term net present value (NPVS) and maximizing long-term NPV (NPVL). The second study is applied to a sector model of a Middle Eastern oil field developed by waterflooding to maximize cumulative oil production and minimize cumulative water production. The real field sector model consists of four producers and three injectors and it is run for ten years with 20 time steps. Bottom-hole pressure (BHP) for producers and water injection rates (qwi) for injectors are the decision variables used in the two studies. EvoNN data-driven model is based on the predator-prey genetic algorithm used in the training and optimization of the data. The optimization results obtained by the EvoNN algorithm are then used as guiding input in the NSGA-II optimization to re-initialize the population. Overall, the Pareto optimal solution obtained by the EvoNN guided NSGA-II has a more optimal solution with better convergence and diversity compared to the NSGA-II solution. The hybrid approach of using EvoNN guided NSGA-II resulted in a 70% improvement in the convergence and the computation demand for the Brugge field model. For the real field sector model, EvoNN guided NSGA-II algorithm resulted in a better convergence obtained at all generations compared to the NSGA-II algorithm solution. The maximum total oil production determined by EvoNN guided NSGA-II is 550.6 Mm3 compared to 522 Mm3 by NSGA-II. Water oil ratio (WOR) is reduced with lower water production obtained by the EvoNN guided NSGA-II algorithm compared to the NSGA-II algorithm. The best optimal solution from the EvoNN guided NSGA-II optimization for the real field sector is determined by the net flow method (NFM) at 521.25 Mm3 oil and 5208.6 Mm3water. The Pareto optimal solutions obtained by the EvoNN guided NSGA-II algorithm provide multiple optimum solutions for the decision-maker to manage the production and injection of the wells in the waterflood development based on the requirements and operational conditions.

Investigation on aquathermolysis desulfurization by cutting off C-S bond in thiophene over Fe-Zr-Al catalyst facilitated by surfactants

ABSTRACT This study aimed to apply aquathermolysis technology to remove thiophene sulfur in vacuum residue to obtain qualified petroleum coke products based on a well-designed Fe-Zr-Al catalyst. A coprecipitation method was first developed to synthesize Fe-Zr-Al composite metal oxide catalyst. The thiophene model oil was selected as the reaction system to investigate the process conditions. By adding surfactants into the reaction system to strengthen the mass transfer process of oil–water two-phase, the desulfurization rate of aquathermolysis was improved. It was shown in this study that under the conditions of oil–water ratio of 3:7, temperature of 280°C, pressure of 4 MPa and reaction duration of 60 h, the desulfurization rate could reach 44.39%. The further introduction of 2.4% Sorbitan oleate into the above reaction system could significantly enhance the desulfurization rate to 60.20%. Under the action of Fe2O3 lattice oxygen, thiophene was oxidized and C-S bond was broken, so as to achieve the purpose of desulfurization. The decomposition of water generated active oxygen to continuously replenish lattice oxygen of Fe2O3. The current founding can provide a new way for the effective desulfurization of vacuum residue to produce qualified petroleum coke products.

Precise Fabrication of Porous Microspheres by Iso-Density Emulsion Combined with Microfluidics

Polymer porous microspheres with large specific surface areas and good fluidity have promising important applications in the biomedical field. However, controllable fabrication of porous microspheres with precise size, morphology, and pore structure is still a challenge, and phase separation caused by the instability of the emulsion is the main factor affecting the precise preparation of porous microspheres. Herein, a method combining the iso-density emulsion (IDE) template and microfluidics was proposed to realize the controllable preparation of polymer porous microspheres. The IDE exhibited excellent stability with minimal phase separation within 4 h, thus showing potential advantages in the large-scale preparation of porous microspheres. With the IDE template combined microfluidics technique and the use of a customized amphoteric copolymer, PEG-b-polycaprolactone, polycaprolactone (PCL) porous microspheres with porosity higher than 90% were successfully prepared. Afterwards, the main factors, including polymer concentration, water–oil ratio and homogenization time were investigated to regulate the pore structure of microspheres, and microspheres with different pore sizes (1–30 μm) were obtained. PCL porous microspheres exhibited comparable cell viability relative to the control group and good potential as cell microcarriers after surface modification with polydopamine. The modified PCL porous microspheres implanted subcutaneously in rats underwent rapid in vivo degradation and tissue ingrowth. Overall, this study demonstrated an efficient strategy for the precise preparation of porous microspheres and investigated the potential of the as-prepared PCL porous microspheres as cell microcarriers and micro-scaffolds.