Azizollah Khormali; Dmitry Gennadievich Petrakov; Georgy Yuryevich Shcherbakov
Abstract
A fundamental study of scale formation of calcium carbonate (CaCO3) for producing oil wells has been carried out. This article presents the study of the prediction of salt deposition in two different synthetic formation waters and investigates the effects of temperature and pressure on calcium carbonate ...
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A fundamental study of scale formation of calcium carbonate (CaCO3) for producing oil wells has been carried out. This article presents the study of the prediction of salt deposition in two different synthetic formation waters and investigates the effects of temperature and pressure on calcium carbonate precipitation. The dependence of the induction period of the precipitation of calcium carbonate on the concentration of calcium ions was studied. In order to study the chemical scale inhibition, the most effective inhibitors, which are based on the risk analysis of scaling and laboratory reagent selection, were examined for evaluating the performance of salt inhibition. In this work, a new multi-component inhibitor was made and its scale effectiveness was evaluated at different concentrations. The developed inhibitor was mixed with other inhibitors to prevent calcium carbonate precipitation. The observations showed the synergetic inhibition effect on the scale inhibition at different concentrations of scale inhibitors. The new inhibitor provided high scale effectiveness at specific concentrations and low corrosion activity.
Mehdi Afkhami Ardakani; Ehsan Mehrabanfar
Abstract
Organizational silence is defined as the lack of effective interactions among staff and it stands opposite to the concept of organizational voice. In the present research, the purpose is to measure the silence behavior among the Research Institute of Petroleum Industry (RIPI) staff before and after the ...
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Organizational silence is defined as the lack of effective interactions among staff and it stands opposite to the concept of organizational voice. In the present research, the purpose is to measure the silence behavior among the Research Institute of Petroleum Industry (RIPI) staff before and after the implementation of a comprehensive suggestion system. A suggestion system is an internal structure easily accessed by all the staff to state their suggestions in a pre-structured format. The roots of silence behavior are studied based on a deep literature review to find out possible solutions to improve organizational voice. To conduct the research, a self-structured questionnaire has been developed and distributed among all the staff. A quasi-experimental methodology has been adopted to compare pretest and post-test results of silence status before and after implementing the suggestion system. The results show that the silence behavior has been meaningfully reduced. This is based on a simple t-test performed by SPSS software, where there is a meaningful difference between the silence status of pre-test and post-test. In other words, a suggestion system could be a communication opportunity to encourage staff to provide suggestions and to cooperate for promoting the organization, which will finally reduce the organization silence. A major gap within the studies of Iranian scholars about organizational silence is the failure to introduce effective solutions to reduce it. However, this research is innovative in the sense that it fills the mentioned gap. This research shows that large scale organizations like RIPI need to consider methods like suggestion systems to break bureaucratic obstacles so that their staff can easily find open routes to share their ideas and suggestions in a prestructured format. This cooperating will lead to mutual benefits for both parts, since suggestions could be used to enhance organizational structure and performance and the staff could also witness their impact on organizational improvements.
Niloufar Bahramipanah; Iman Danaee; Maryam Kanani; Mohammad Hosein Maddahy
Abstract
As an alternative to chromate conversion coatings, rare-earth coatings especially cerium, because of the low toxicity, have attracted considerable attention. Using dip immersion method, cerium-based conversion coating was deposited on aluminum 2024. Corrosion resistance was studied in 3.5 wt.% NaCl solution ...
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As an alternative to chromate conversion coatings, rare-earth coatings especially cerium, because of the low toxicity, have attracted considerable attention. Using dip immersion method, cerium-based conversion coating was deposited on aluminum 2024. Corrosion resistance was studied in 3.5 wt.% NaCl solution using potentiodynamic polarization, electrochemical impedance spectroscopy, and surface methods. The coated samples revealed a considerable decrease in corrosion rate and with increasing immersion time up to 1200 s, the coating resistance increased. Electrochemical impedance data showed that the aluminum charge transfer resistance was increased in the existence of cerium oxide conversion coatings. Using energy dispersive spectroscopy (EDS) and scanning electron microscopy (SEM), the chemical composition and surface morphology were also evaluated.
Hamid Rahmati; Farzad Mahboobi
Abstract
In some engineering fields, wear resistance and a low friction coefficient are required at the sametime. In this research, PTFE nanoparticles and carbon nanotubes were co-deposited within Ni-Pmatrix to obtain an Ni-P-PTFE-CNT hybrid coating for wear resistance and a low friction coefficient.The tribological ...
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In some engineering fields, wear resistance and a low friction coefficient are required at the sametime. In this research, PTFE nanoparticles and carbon nanotubes were co-deposited within Ni-Pmatrix to obtain an Ni-P-PTFE-CNT hybrid coating for wear resistance and a low friction coefficient.The tribological properties of the deposits were evaluated by pin on disc tribometer. The morphologyof the coatings and worn surface was evaluated by scanning electron microscopy. However, theresults showed that the addition of PTFE nanoparticles to the Ni-P electroless coating caused thefriction coefficient to decrease to values lower than 0.2, which led to an improvement in frictionbehavior because of its self-lubricity properties; it, however, decreased the strength of coating due topolymeric and soft structure of the molecules. The simultaneous incorporation of PTFE nanoparticlesand carbon nanotubes can provide the properties of both molecules and increased the strength ofcoating with a low friction coefficient and self-lubricity properties. Therefore, the wear rate and thedegradation of surface were decreased during the wear process.
Petroleum Engineering – Drilling
Hossein Yavari; Mohammad Sabah; Rassoul Khosravanian; David. A Wood
Abstract
The rate of penetration (ROP) is one of the vital parameters which directly affects the drilling time and costs. There are various parameters that influence the drilling rate; they include weight on bit, rotational speed, mud weight, bit type, formation type, and bit hydraulic. Several approaches, including ...
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The rate of penetration (ROP) is one of the vital parameters which directly affects the drilling time and costs. There are various parameters that influence the drilling rate; they include weight on bit, rotational speed, mud weight, bit type, formation type, and bit hydraulic. Several approaches, including mathematical models and artificial intelligence have been proposed to predict the rate of penetration. Previous research has showed that artificial intelligence such as neural network and adaptive neuro-fuzzy inference system are superior to conventional methods in the prediction of drilling rate. On the other hand, many complicated analytical ROP models have also been developed during recent years that are able to predict drilling rate with a high degree of accuracy. Therefore, comparing different approaches to find the most accurate model and assess the conditions in which each model works well can be highly effective in reducing drilling time as well as drilling cost. In this study, Hareland-Rampersad (HR) model, Bourgoyne and Young (BY) model, and an adaptive-neuro-fuzzy inference system (ANFIS) are employed to predict the drilling rate in the South Pars gas field (SP) offshore of Iran, and their results are compared to find the best ROP-prediction model for each formation. A database covering the drilling parameters, sonic log data, and modular dynamic test data collected from several drilling sites in SP are used to construct the mentioned models for each formation. The results show that when a large amount of data is available, the ANFIS is more accurate than the other approaches in predicting drilling rate. In the case of ROP models, BY model works considerably better than HR model for the majority of the formations. However, in formations where some drilling parameters are constant, but formation strength is variable, HR model shows better prediction performance than BY model.
Petroleum Engineering
Mohammad Hossein Shabani; Arezou Jafari; Seyed Mohammad Mousavi
Abstract
Microbial enhanced oil recovery (MEOR) is an economical method used to improve the oil recovery from reservoirs. In the MEOR techniques, by applying different microorganisms, a variety of products such as bioacid, biogas, biosurfactant, and biopolymer are generated, among which biosurfactant, one of ...
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Microbial enhanced oil recovery (MEOR) is an economical method used to improve the oil recovery from reservoirs. In the MEOR techniques, by applying different microorganisms, a variety of products such as bioacid, biogas, biosurfactant, and biopolymer are generated, among which biosurfactant, one of the important metabolites, is produced by bacteria. It is worthy to note that bacteria are suitable candidates to enhance oil recovery due to their small size, rapid growth, capability of tolerating reservoir conditions, and production of different metabolites. Therefore, in this research, two bacteria, namely Enterobacter cloacae subsp with PTCC: 1798 isolated from oil-contaminated soil in south of Iran and Acinetobacter Calcoaceticus with PTCC: 1318, are used to produce biosurfactants. In order to evaluate the performance of generated biosurfactants, ex-situ flooding tests were performed in a glass micromodel to visualize the oil displacement and fluid front flow. In addition, water flooding is performed as a common EOR method for the better investigation of the produced biosurfactants. The results represented that injecting Enterobacter with a salinity concentration of 6% and Acinetobacter with a salinity concentration of 3% respectively increases the oil recovery factor by 27 and 35% compared to water flooding. In other words, the highest reduction in interfacial tension is achieved by the biosurfactant produced from Enterobacter and Acinetobacter at 6% and 3% salinity respectively, and the sequent changes in the interfacial tension are from 45 to 7 and 45 to 4 mN/m.
Zahra Heidari; Mohsen Motevasel; Nemat Allah Jaafarzadeh
Abstract
Pentachlorophenol (PCP) is a very hazardous compound which enters into the environment by industries such as refineries and petrochemicals. As its biological degradation is very slow, this use may cause the pollution of soils and groundwater; with the recent emergence of pentachlorophenol contamination ...
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Pentachlorophenol (PCP) is a very hazardous compound which enters into the environment by industries such as refineries and petrochemicals. As its biological degradation is very slow, this use may cause the pollution of soils and groundwater; with the recent emergence of pentachlorophenol contamination as an important drinking water quality issue, finding an easy, economical, and useful method to remove it has been attracted interest. In this study, the performance of an electro-Fenton process (EFP) for the elimination of PCP from an aquatic environment was evaluated. The effects of important operational variables such as reaction time, pH, the applied voltage, and the distance between the electrodes on the degradation of solution were investigated. The maximum PCP removal was obtained at a distance of 3 cm, a pH of 3, a voltage of 24 volt, and the treatment time of 40 min. This study demonstrated that the distance between the electrodes, pH, the applied voltage, and the treatment time have significant effects on the electron-Fenton process and this process is suitable for the treatment of PCP-polluted waste waters.
Seyyed Mohsen Hosseini; Khalil Shahbazi; Mohammad Reza Khosravi Nikou
Abstract
Among the all parameters affecting the performance of a downhole de-oiling hydrocyclone, the investigation of internal flow field deserves more attempts especially in the petroleum industry. In this study, the effects of inlet flow rate, inlet oil volume fraction, and oil droplet diameter on the separation ...
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Among the all parameters affecting the performance of a downhole de-oiling hydrocyclone, the investigation of internal flow field deserves more attempts especially in the petroleum industry. In this study, the effects of inlet flow rate, inlet oil volume fraction, and oil droplet diameter on the separation efficiency and pressure drop ratio have been investigated along the hydrocyclone body. All the simulations were performed using computational fluid dynamics (CFD) techniques, in which the Eulerian multiphase model and the Reynolds stress turbulent model were employed for the prediction of multiphase and turbulent flow parameters through the hydrocyclone. The velocity component profiles, separation efficiency, pressure drop, and volume fraction are also other parameters which have been considered in this work. The results of the simulations illustrate good agreement with the reported experimental data. Furthermore, the simulations indicate that the separation efficiency almost increases twofold, when the droplet diameter increases from 25 to 50 micron. The effect of inlet flow rate on the separation efficiency is so significant that an increase in inlet flow rate from 5 to 25 l/min causes a sharp increase in the separation efficiency and raises it 2.5 times the initial value. However, the inlet oil volume fraction showed a minor effect on the hydrodynamic flow behavior in the hydrocyclone body compared to the other investigated parameters.
Hamidreza Mousavi; Mehdi Shahbazian; Nosrat Moradi
Abstract
Recently different approaches have been developed in the field of sensor fault diagnostics based on Auto-Associative Neural Network (AANN). In this paper we present a novel algorithm called Self reconstructing Auto-Associative Neural Network (S-AANN) which is able to detect and isolate single faulty ...
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Recently different approaches have been developed in the field of sensor fault diagnostics based on Auto-Associative Neural Network (AANN). In this paper we present a novel algorithm called Self reconstructing Auto-Associative Neural Network (S-AANN) which is able to detect and isolate single faulty sensor via reconstruction. We have also extended the algorithm to be applicable in multiple fault conditions. The algorithm uses a calibration model based on AANN. AANN can reconstruct the faulty sensor using non-faulty sensors due to correlation between the process variables, and mean of the difference between reconstructed and original data determines which sensors are faulty. The algorithms are tested on a Dimerization process. The simulation results show that the S-AANN can isolate multiple faulty sensors with low computational time that make the algorithm appropriate candidate for online applications.
Mohammadreza Shishesaz; Mehdi Robat Sarpoushi; Mohammad Ali Golozar
Abstract
In this paper, the effect of cationic and anionic ion sizes on the charge storage capability of graphene nanosheets is investigated. The electrochemical properties of the produced electrode are studied using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques in 3M NaCl, ...
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In this paper, the effect of cationic and anionic ion sizes on the charge storage capability of graphene nanosheets is investigated. The electrochemical properties of the produced electrode are studied using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques in 3M NaCl, NaOH, and KOH electrolytes. Scanning electron microscopy (SEM) is used to characterize the microstructure and nature of the prepared electrode. The SEM images and X-ray diffraction (XRD) patterns confirm the layered structure (12 nm thickness) of the used graphene with an interlayer distance of 3.36 Å. The electrochemical results and the ratio of confirm good charge storage and charge delivering capability of the prepared electrode in the 3M NaCl electrolyte. Charge/discharge cycling tests show a good reversibility and confirm that the solution resistance will increase after 500 cycles.
In this paper, the effect of cationic and anionic ion sizes on the charge storage capability of graphene nanosheets, is investigated. Electrochemical properties of produced electrode are studied using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques, in 3M NaCl, NaOH and KOH electrolytes. Scanning electron microscopy (SEM) is used to characterize the microstructure and nature of prepared electrode. SEM images and XRD patterns confirm the layered structure (12 nm thickness) of the used graphene with an interlayer distance of 3.36 (Å). The electrochemical results and the ratio of q*O/q*T confirm a good charge storage and charge delivering capability of prepared electrode in 3M NaCl electrolyte. Charge/discharge cycling test shows a good reversibility and confirms that solution resistance will increase after 500 cycles.
Petroleum Engineering
Shahin Kord; Omid Ourahmadi; Arman Namaee-Ghasemi
Abstract
Production strategy from a hydrocarbon reservoir plays an important role in optimal field development in the sense of maximizing oil recovery and economic profits. To this end, self-adapting optimization algorithms are necessary due to the great number of variables and the excessive time required for ...
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Production strategy from a hydrocarbon reservoir plays an important role in optimal field development in the sense of maximizing oil recovery and economic profits. To this end, self-adapting optimization algorithms are necessary due to the great number of variables and the excessive time required for exhaustive simulation runs. Thus, this paper utilizes genetic algorithm (GA), and the objective function is defined as net present value (NPV). After developing a suitable program code and coupling it with a commercial simulator, the accuracy of the code was ensured using a synthetic reservoir. Afterward, the program was applied to an Iranian southwest oil reservoir in order to attain the optimum scenario for primary and secondary production. Different hybrid water/gas injection scenarios were studied, and the type of wells, the number of wells, well coordination/location, and the flow rate (production/injection) of each well were optimized. The results from these scenarios were compared, and simultaneous water and gas (SWAG) injection was found to have the highest overall profit representing an NPV of about 28.1 billion dollars. The application of automated optimization procedures gives rise to the possibility of including additional decision variables with less time consumption, and thus pushing the scopes of optimization projects even further.
Iman Moghri; Mansoor Farzam; Mohammadreza Shishesaz; Davood Zaarei
Abstract
In this study, nanocomposite coatings based on polyurethane cerium nitrate montmorillonite (MMT) were prepared, applied on carbon steel substrates, and investigated. The nanocomposite coatings were successfully prepared by the effective dispersing of nanoparticles in polyurethane resin by mechanical ...
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In this study, nanocomposite coatings based on polyurethane cerium nitrate montmorillonite (MMT) were prepared, applied on carbon steel substrates, and investigated. The nanocomposite coatings were successfully prepared by the effective dispersing of nanoparticles in polyurethane resin by mechanical and sonication processes. The state of dispersion, dissolution, and incorporation were characterized by optical microscopy, sedimentation tests, and transmission electron microscopy. The structure and properties of the nanocomposite coatings were investigated by X-ray diffraction and anticorrosive properties of the nanocomposites were studied by Tafel polarization measurements. The experimental results showed that the PU/MMT/Cerium nitrate nanocomposite coatings were superior to the neat PU in corrosion protection. In addition, it was observed that the corrosion protection of the nanocomposite coatings was improved as the clay and cerium nitrate loadings were increased to 4 wt.% to 2 wt.% respectively.
Petroleum Engineering
Hojatallah Koraee; Hadi Eskandari; Iman Danaee
Abstract
Corrosion results in hazardous and expensive damage to pipelines, vehicles, water and wastewater systems, and even home appliances. One of the most extensively practical methods for protecting metals and alloys against corrosion is to use organic inhibitors. The inhibition capability of 2-Mercaptobenzothiazole ...
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Corrosion results in hazardous and expensive damage to pipelines, vehicles, water and wastewater systems, and even home appliances. One of the most extensively practical methods for protecting metals and alloys against corrosion is to use organic inhibitors. The inhibition capability of 2-Mercaptobenzothiazole (2-MBT) against the corrosion of carbon steel in a 2 M NaCl solution was examined by Tafel polarization. By using 2-Mercaptobenzothiazole both the cathodic and anodic reactions are delayed through chemical and physical adsorption and blocking the active corrosion sites. Based on the polarization curves, it was indicated that by increasing the inhibitor concentration, the inhibition efficiency increases up to 70% at room temperature, and it improves at higher temperatures. The adsorption of 2-Mercaptobenzothiazole was based on the Langmuir adsorption isotherm. The enthalpies of activation were determined to be around +50 kJ.mol-1. The endothermic nature of the steel dissolution procedure is reflected by the positive symbols of the enthalpies (ΔH) of activation process. The determined values range from -32.69 to -35.81 kJ.mol-1, which shows both electrostatic adsorption and the chemisorption of the adsorption mechanism. The calculated entropy of adsorption was 78 J.mol-1.K-1 indicating the increment in the solvent entropy and a more positive water desorption entropy.
Energy Systems Engineering
Mehdi Mahmoodi; Mofid Gorji Bandpy
Abstract
When a natural gas pipeline ruptures, the adjacent upstream and downstream automatic control valves (ACV) should close quickly to prevent leakage or explosion. The differential pressure set point (DPS) at each valve location is the main criteria for value setting in ACV actions. If the DPS is not properly ...
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When a natural gas pipeline ruptures, the adjacent upstream and downstream automatic control valves (ACV) should close quickly to prevent leakage or explosion. The differential pressure set point (DPS) at each valve location is the main criteria for value setting in ACV actions. If the DPS is not properly adjusted, the ACV may mistakenly close or it may not take any actions at a proper time. In this study, the effect of characteristic parameters such as pipeline operational pressure (POP) and pipeline pressure drop rate (ROD) due to rupture or a major leak was experimentally investigated on DPS. 25 different conditions with the double set of the mentioned typical characteristic parameters were chosen. In each condition, the differential pressure (DP) was measured over a period of 180 s by statistically analyzing the experimental results, so 25 maximum DP values (DPSs) were obtained. The DPS rises by an increase in ROD or a decrease in POP. Because of using nitrogen gas instead of natural gas for safety reasons and the uncertainties, the DPS results can be practically applied by adding a safety factor of 15%. Finally, the diagram of DPS with respect to ROD and that of non-dimensional DPS (DOP) versus non-dimensional ROD (RTP) were provided for different POP’s.
Chemical Engineering – Gas Processing and Transmission
Cyrus Fallahi; Sadegh Moradi; Reza Masayebi Behbahani
Abstract
In the present study, the permeabilities of CO2 and CH4 in terms of ideal and actual CO2/CH4 selectivity were investigated through the synthesized membranes of poly (ether-block-amide) (Pebax 1657) accompanied with poly (ethylene glycol) (PEG 400) and NH2-MIL125 nanoparticles. NH2-MIL125 nanofillers ...
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In the present study, the permeabilities of CO2 and CH4 in terms of ideal and actual CO2/CH4 selectivity were investigated through the synthesized membranes of poly (ether-block-amide) (Pebax 1657) accompanied with poly (ethylene glycol) (PEG 400) and NH2-MIL125 nanoparticles. NH2-MIL125 nanofillers were added to the blend of PEG 400 and Pebax 1657 at various weight fractions to fabricate polymeric nanocomposite membranes. Several analyses such as the crystalline structure of the synthesized membranes, field emission scanning electron microscopy (FESEM) and X-ray diffraction analysis (XRD) were utilized to investigate the cross-sectional and surface morphology of the membranes; the formation of the chemical bonds was identified by Fourier transform infrared (FTIR). This study presents the permeation of both pure and mixed gases ofmethane and carbon dioxide through Pebax 1657, Pebax/PEG blend, and the Pebax/PEG/NH2-MIL125 nanocomposite membranes in a pressure range of 2-8 bar and at ambient temperature. The findings demonstrated that the synthesized nanocomposite membranes had a positive effect on the separation performance in comparison with the membranes made of neat polymer and polymer blends.
Petroleum Engineering – Reservoir
Vahid Karamnia; Siavash Ashoori
Volume 10, Issue 1 , January 2021, , Pages 107-126
Abstract
< p>One of the most important factors through the miscible gas injection process is to determine the Minimum Miscibility Pressure. According to the definition, the minimum miscibility pressure is the minimum pressure at which, at a constant temperature, the oil and gas injected can dissolve together ...
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< p>One of the most important factors through the miscible gas injection process is to determine the Minimum Miscibility Pressure. According to the definition, the minimum miscibility pressure is the minimum pressure at which, at a constant temperature, the oil and gas injected can dissolve together to form a single phase. This pressure is typically abbreviated as MMP. Among the available methods for determining the minimum miscibility pressure, laboratory methods including slim tube test and ascending bubble apparatus test are more widely utilized. Although the mentioned tests have high measurement accuracy, they are very time consuming and expensive. Therefore, the determination of the minimum miscibility pressure is usually done using computational and simulation approaches that also have high accuracy. Conducting PVT tests and determining their MMP using slim tube method was previously performed. In this study, the minimum miscibility pressure of reservoirs was determined by applying three methods of simulation with PVTi software, simulation with Eclipse 300 software and using Empirical Correlations. By comparing the obtained results and the laboratory results, it was revealed that the simulation by Eclipse 300 is regarded as the fastest and most accurate approach.
Technical Inspection Engineering
Zeinab Nassaj; Fatemeh Ravari; Iman Danaee
Abstract
In this paper, graphene oxide decorated with cerium oxide (CeO2) nanoparticles was prepared and used as anticorrosive pigments in epoxy nanocomposite coatings. The synthesized nanoparticle was characterized by FTIR, XRD, SEM, and EDX analyses. Graphene oxide decorated with CeO2 nanoparticles was dispersed ...
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In this paper, graphene oxide decorated with cerium oxide (CeO2) nanoparticles was prepared and used as anticorrosive pigments in epoxy nanocomposite coatings. The synthesized nanoparticle was characterized by FTIR, XRD, SEM, and EDX analyses. Graphene oxide decorated with CeO2 nanoparticles was dispersed in epoxy resin by sonication. The optimum nanoparticle content of the epoxy resin was studied by differential scanning calorimetry. The anticorrosive properties of these coatings were investigated using electrochemical impedance spectroscopy method and polarization in corrosive solution. Impedance parameters showed a decrease in the coating resistance over immersion time. The results indicated that the epoxy coatings containing nanoparticles could significantly increase the corrosion resistance of composite coatings compared to those of pure epoxy, and the highest value was obtained for 1% nanocomposite coatings after 270 days of immersion. Pull-off adhesion test showed that the highest value of adhesion was related to the coating containing 1% nanoparticles.
Volume 5, Issue 1 , January 2016, , Pages 73-78
Volume 3, Issue 3 , July 2014, , Pages 75-80
Volume 5, Issue 4 , October 2016, , Pages 77-82
Volume 3, Issue 4 , October 2014, , Pages 78-83
Volume 3, Issue 2 , April 2014, , Pages 79-84
Volume 5, Issue 3 , July 2016, , Pages 82-87
Volume 4, Issue 4 , October 2015, , Pages 88-94
Volume 6, Issue 2 , April 2017, , Pages 90-95