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Context: This study explores the interaction between particles in microplastic semi-coke water slurry at the molecular level using molecular simulation methods, specifically DFT calculations and MD simulations. In addition, the experiment of slurry preparation was carried out to study the viscosity and stability of the slurry. The electrostatic potential analysis shows that the interaction between microplastics and dispersant molecules occurs on atoms with large electronegativity or oxygen-containing functional groups, and the energy gap of frontier molecular orbitals indicated that PVC interacts most easily with the dispersant (0.39 eV), followed by PS (1.08 eV) and PET (3.65 eV). In addition, it is also noted that due to the steric hindrance effect, the adsorption energy was opposite to the DFT calculation results: PET was − 213.338 kcal/mol (NNO) which was highest, followed by PS (− 107.603 kcal/mol, NNO), and PVC (NNO) was lowest which was − 94.808 kcal/mol. And RDF shows similar results, which the probability of water molecules in the PET system was the highest, followed by PS, and finally, PVC. The MD results are consistent with the viscosity and stability characterization results of the slurry which PET has the lowest viscosity of 87.3 mPa·s. Finally, this study provides new ideas for the treatment of microplastics and the improvement of the performance of semi-coke water slurry and reveals the interaction mechanism between microplastics and semi-coke water slurry. Methods: All calculations were performed using Materials Studio (MS) version 2020 software, BIOVIA Corporation. The DFT calculation was carried out through the DMol3 module. The DFT calculations include electron density, electrostatics, orbitals, and population analysis. In DMol3 module, the GGA-PBE function was selected to consider gradient changes in density in the simulated calculation. The DFT-D correction was selected, and all electrons were calculated by DNP for accurate core potentials and the DNP file was 4.4. MD simulation was performed through the Forcite module. MD simulation mainly focuses on relative concentration distribution analysis, radial distribution function, and adsorption energy calculation. All molecular geometry optimizations are performed in the Forcite module. In the molecular dynamic part, all simulations used PCFF forcefield. The NVT ensemble was adopted and using the Nosé thermostat. [ABSTRACT FROM AUTHOR]

Coal water slurries (CWSs) are considered to be a new form of fuel that can alleviate the environmental and safety issues associated with use of bulk solid fuel. However, CWSs does not always fit into existing solid fuel supply and storage chain. In this study, a novel method to control CWSs viscosity using pH-responsive thickener was proposed, offering the advantages of improved storage stability and on-demand viscosity control, thus allowing CWSs to be used as a c for a variety of applications. This study investigates the effects of additives and pH on the viscosity and storage stability of CWSs. Poloxamer 407, polynaphthalene sulfonate formaldehyde (PNSF), and a copolymer containing pigment-affinic (PA) groups were used as dispersants to lower CWSs viscosity. Xanthan gum, a modified acrylic polymer (MAP), and carbomer were used as thickeners for assessing the storage stability and fluidity of CWSs based on viscosity changes. Optimal viscosity reduction was achieved by the addition of PA. A viscosity of 7000 cP was achieved by the use of carbomer, with small amount comparable to 27.3 wt% of MAP and 22.7 wt% of Xanthan gum. Moreover, the carbomer-containing CWSs exhibited high storage stability in a 360-h stability test, retaining 84.3% of the original baseline coal content. pH-dependent viscosity changes were observed only in carbomer-containing samples. [ABSTRACT FROM AUTHOR]

The primary objective of this investigation was to explore the electrochemical oxidation behavior of Sorbitan monolaurate (Span 20) under high-voltage environments. We designed and prepared working electrodes using a mixture containing Span 20 and conductive carbon black as an electron transport material. Linear sweep voltammetry (LSV) served as the technique to monitor the reactions undergone by Span 20. The oxidative products were subjected to analysis using X-ray photoelectron spectroscopy (XPS) and nuclear magnetic resonance hydrogen spectrum (1H NMR). LSV reveals the decomposition of Span 20 occurring at voltages exceeding 4.2 V, involving two distinct reactions. Further insights from XPS and 1H NMR demonstrated that Span 20 underwent a two-electron-two-proton electrochemical reaction, producing triketone and 1, 3-diketone with a hydroxyl group positioned at the 2 position. To elucidate these results, a reasoning mechanism was proposed. [ABSTRACT FROM AUTHOR]

The industrial production of fuel ethanol is carried out by a fermentation process with yeast Saccharomyces cerevisiae commercial cell recycling resulting in excess foam formation. The present work aims to evaluate the performance of a commercial enzymatic preparation (FermaxTM) as a defoaming agent in industrial bioethanol process. The enzymatic preparation was applied concomitant with traditional chemicals. The application was carried out by pumping the enzymatic preparation into the fermentation tanks. Assay 1, in continuous mode in the treated yeast dilution tank, while assay 2, was conducted in batch mode, after sending the yeast to the fermentation tanks. The monitoring of the process was carried out by quantifying the indicators of a fermentation process. Assays 1 and 2 showed average reductions in the consumption of defoamer and dispersant of 26% and 37%, respectively. In the assay 1, the strategy of reducing the mix of ethanol production was adopted, resulting in reductions in wort flow, ethanol production, and rate of occupation of tanks. Assay 1 resulted in similar values to the traditional process without the addition of enzyme. However, in assay 2, the strategy to reduce the ethanol production mix was not adopted. In this condition, there were no significant differences in the indicators of the fermentation process between the control and enzyme periods. Assay 1 presented a net cost reduction of 15%, while assay 2 presented a net cost increase of 9%, with resources for the acquisition of chemical inputs, which totaled savings of R$ 0.40 in assay 1 and a loss of R$ 0.18 in assay 2 per cubic meter of ethanol. The decrease in the ethanol production mix was the most appropriate moment for the application of the enzyme preparation. [ABSTRACT FROM AUTHOR]

The stability and dispersion of Copper (Cu) powders in an aqueous medium impacts their performances. Thus the Cu powder suspensions were prepared by adding different stabilizers—sodium dodecyl sulfate (SDS), sodium dodecylbenzene sulfonate (SDBS), polyvinyl pyrrolidone (PVP), and hexadecyl trimethyl ammonium bromide (CTAB); the best surfactant was selected and its stability and dispersion were studied. The study systematically examined the effect of the stability of suspensions via sedimentation analysis, including solid–liquid ratio, the concentration of stabilizer, and dispersion time. The particle size, the stability of suspensions, phase composition, and microstructure of Cu powders were characterized by laser particle size analyzer, zeta potential, X-ray diffraction (XRD), transmission electron microscope (TEM), and scanning electron microscope (SEM). The results indicate that the stability of the suspension is improved with the addition of PVP due to the steric hindrance of PVP, and the growth and agglomeration of particles are retarded by the formation of a thick hydration layer with the optimizing concentrations, dispersion time, and solid–liquid ratio 10 g/L, 30 min, and 1:25, respectively. [ABSTRACT FROM AUTHOR]

In this study, the effect of a polyisobutenyl succinimide (PIB) dispersant on the tribological performances of MoS2 nanoparticles used as lubricant additives in a PAO base oil was investigated. Friction tests were conducted in boundary lubrication regime, in a steel/steel sliding contact configuration, at room temperature and at 100 °C. The tribofilms formed on the rubbed surfaces were analyzed using X-ray Photoelectron Spectroscopy (XPS) and Transmission Electron Microscopy (TEM). The results show that the dispersant used in this work prevented the agglomeration/sedimentation of the nanoparticles and strongly improved their dispersion in the base oil. Its effect on the tribological performance of the nanoparticles was found to be temperature dependent. The best friction-reducing properties were obtained at elevated temperature. It was also found that the dispersant strongly affected the tribofilm's properties (chemical composition, thickness, MoS2 flake length) and that the best reducing friction properties were obtained when the tribofilm was composed of long and well-dispersed MoS2 flakes aligned in the sliding directions. [ABSTRACT FROM AUTHOR]

Polycarboxylic acid dispersant has the advantages of good dispersion performance and environmental protection, and has a good application prospect in oil well cement. However, the current polycarboxylic acid dispersant has poor temperature resistance, which limits its application in high-temperature formation cementing. In this study, a polycarboxylic acid dispersant (NLPC) that can be applied to high-temperature cementing was synthesized by free radical copolymerization of monomer isoprenol polyoxyethylene ether, maleic acid, 2-acrylamido-2-methylpropanesulfonic acid and N-vinyl-2-pyrrolidone. The structure of NLPC was characterized by Fourier transform infrared spectroscopy, gel permeation chromatography and 1H nuclear magnetic resonance spectroscopy. The effects of NLPC on the fluidity, rheological properties, thickening time and mechanical strength of cement slurry at different temperatures were tested, and compared with the traditional sulfonated acetone-formaldehyde polycondensate (SAF) dispersant. The mechanism of dispersant and its effect on cement hydration behavior were systematically studied by total organic carbon, Zeta potential, particle size analysis, thermogravimetric analysis and X-ray diffraction analysis. The effect of dispersant on the microstructure of hardened cement was analyzed by scanning electron microscopy. The results show that NLPC has excellent high temperature dispersion performance. At 150 °C, NLPC can significantly reduce the consistency coefficient of cement slurry, increase the fluidity index of cement slurry, significantly improve the rheological properties of cement slurry, and the paste has excellent thickening performance, and the initial consistency is lower than SAF. In addition, due to the good dispersion of cement particles by NLPC, the early mechanical strength of cement stone after solidification is also improved. The mechanism analysis shows that NLPC improves the dispersion performance of oil well cement slurry mainly through electrostatic repulsion and steric hindrance effect. In a word, NLPC overcomes the shortcomings of low efficiency and heavy pollution of SAF dispersant and the low applicable temperature of current polycarboxylic acid dispersant products, which is of great significance to ensure the smooth operation of high temperature deep well cementing and improve the cementing quality. Highlights: NLPC improves the temperature resistance of polycarboxylic dispersant. NLPC improves the rheological properties of oil well cement slurry at high temperature. The mechanism of NLPC is steric hindrance and electrostatic repulsion. NLPC has good compatibility with other oil well cement additives and has no adverse effect on the implementation of cementing engineering. [ABSTRACT FROM AUTHOR]

The current work focuses on experimental studies using Mesua Ferrea biodiesel (BD20) and Cr2O3 nanoparticles in a diesel engine. In different concentrations, 60, 80, and 100 mg/L Cr2O3 nanoparticles were mixed. In addition, the dispersant (QPAN80) and surfactant (CTAB) were used to change the surface of the Cr2O3 nanoparticle (at a 1:1 ratio). The compression ratios were varied such as; 16.5:1, 17.5:1, and 18.5:1, respectively. Using a mechanical agitator and a probe sonicator, the nanofuel was produced by inserting the surface modified Cr2O3 nanoparticles into BD20. The combustion characteristics of nanoparticles added to BD20, such as cylinder pressure (CP) and net heat release rate (NHRR) have improved greatly over normal diesel. However, nanofuels improved performance in terms of brake specific fuel consumption (BSFC) and brake thermal efficiency (BTE). Together with NOx, the emission characteristics (CO, UHC, and smoke) were reduced momentously. Eventually, a good trend in performance, combustion, and emissions were seen as the compression ratio increased. The dispersant added nanoparticles in BD20 has shown good outcomes than the surfactant added nanoparticles and base nanoparticles. The BD20 + Cr2O3 80 mg/L + DSP 80 mg/L had the best results of all the test samples. At CR 18.5:1, the BTE, BSFC, CP, and NHRR were 34.52%, 0.342 kg/kWh, 65.52 bar, and 88.79 J/oCA, respectively, whereas CO, UHC, smoke opacity, and NOx were, 0.092%, 35 ppm, 20.26%, and 1249 ppm, respectively. [ABSTRACT FROM AUTHOR]

This article describes a comparative evaluation of effectiveness of certain commercial dispersants (Finasol OSR 52 (France) and Slickgone NS and Slickgone EW (Great Britain)) for spill response of three crude oils produced in Russia and characterized by different physicochemical properties (extra light, heavy, and bituminous) in waters of various salinity. The evaluation has been based on an adapted version of ASTM F2059-17 "Standard Test Method for Laboratory Oil Spill Dispersant Effectiveness Using the Swirling Flask" (the so called SFT test). The conventional lower limits of dispersant effectiveness have been determined using a low energy procedure. Comparative tests of dispersant effectiveness have been performed at the highest dispersant-to-oil ratio of 1 : 10 allowed in the Russian Federation (according to STO 318.4.02-2005 "Rules of Dispersant Application for Oil Spill Response"), water temperature 20°C, and water salinity of 0, 5, 10, 20, and 35‰. It has been revealed that the considered dispersants have low effectiveness for dispersion of the tested oil samples at water salinity of 35‰. A general trend of increase in dispersant effectiveness with decrease in water salinity is demonstrated. It has been established that all considered dispersants are not suitable for application throughout the analyzed salinity range in the case of spill of bituminous oil with high content of asphaltenes and polar compounds. The limits of dispersant application have been determined for all dispersants as a function of water salinity. The effectiveness of 45%, legally validated in the United States and Mexico, has been selected as the threshold value. It has been proved that, as a consequence of nonuniversality of dispersant action, it is recommended to carry out preliminary experimental examination of their effectiveness using a sample of spilled oil under climatic and hydrochemical conditions corresponding to the potential region of application. [ABSTRACT FROM AUTHOR]

PU foams are widely used in the automobile industry not only for their lightweight properties, but also as sound-absorbing and seat cushioning materials. The effects of particles on the sound absorption properties of PU composite foams were investigated. PU foams containing 3 wt% melamine particles showed excellent sound absorption properties. However, when the particle content exceeded 3 wt%, particle agglomeration occurred, leading to reduced sound absorption. A dispersant was added during the fabrication process to improve the interfacial compatibility between the PU matrix and melamine particles, resulting in a well-developed cavity and pore structure. The sound absorption characteristics of the PU composite foams were significantly improved in the frequency range below 2,000 Hz. Our study highlights the importance of adjusting the concentration of particles and optimizing the cavity and pore structure of the material for achieving better sound absorption properties in PU composite foams. [ABSTRACT FROM AUTHOR]

In this research, ZnFe2O4 absorbing materials were prepared via co-precipitation, employing different dispersants, namely, PEG20000, SDS, and CTAB, and using Na2CO3 as a precipitant. SEM, XRD, XPS, VSM, and VNA were employed to analyze the morphology, structure, absorption loss, and other properties of ZnFe2O4 absorbing materials. Then, the effects of different dispersants on the morphology and absorption performance of ZnFe2O4 materials were discussed. The results show that different dispersants can impose a great influence on the dispersion of the prepared ZnFe2O4 particles, which in turn show different attenuation degrees after the incidence of electromagnetic waves. To be specific, when SDS was selected as the dispersant for ZnFe2O4 material, the micelles formed by SDS exhibited better adsorption capacity for Zn2+ and Fe2+ in an aqueous solution, and the metal ions reacted with the precipitant to precipitate on the surface of the micelles. Thus, this facilitated the complete dispersion of the precipitate within the aqueous solution. The final prepared particles were spherical in terms of its shape, uniform particle size, about 20 nm, which demonstrated good dispersion performance with minimum reflection loss of −30.9 dB and effective absorption bandwidth of 5.66 GHz. [ABSTRACT FROM AUTHOR]

The influence of different dispersants on the dispersion of Y2O3 sintering aid in B4C powder and the microstructure and performance of the subsequently hot-pressed ceramics were studied in this paper. The results indicated that ammonium polycarboxylate (APC) could effectively enhance the distribution of Y2O3 in B4C powder, and further improve the distribution homogeneity of the formed second phase YB4 in the fabricated ceramics. Polyethyleneglycol (PEG) 600 was beneficial to breaking the Y2O3 agglomeration in B4C powder and improving the distribution of YB4. The remaining PEG 600 in the mixed powder would react with B4C and Y2O3 particles to form the dendritic-structure second phase in the sintering process, which comprised some whisker-like branches and a layer of film. The distribution of YB4 in the fabricated ceramics was slightly improved by adding sodium citrate (SC) dispersant. Y2O3 reacted with B4C to form the intergranular and intragranular YB4, and liquid phase was formed in the sintering process, facilitating the rearrangement of B4C grains and improving the densification. The dispersant APC could improve the homogeneity of YB4, promoting the densification and strength of the ceramics. [ABSTRACT FROM AUTHOR]

MgO-based cementitious material (MCM) is a potential green substitute for solidifying municipal solid waste incineration fly ash (MSWI FA). Sodium hexametaphosphate (SHMP), a commonly used dispersant, has a great influence on the hydration process of MCM-MSWI FA blends. In this study, the effect of different SHMP additions on the performance of the MCM-MSWI FA (3:7 in mass ratio) blends was investigated. The compressive strength and leaching toxicity of the blends were measured, and the structural evolution was analyzed by XRD, FTIR, TG/DTG, and SEM. These tests revealed that the addition of SHMP could significantly optimize the effect of MCM solidifying MSWI FA since SHMP could promote the dispersion of hydration products in the blends. The blends containing more than 1% SHMP exhibited immobilization efficiencies higher than 97.5% for heavy metals (Cd, Pb, and Zn) after curing for 28 days. Collectively, this work demonstrates the indispensable role of SHMP in the application of MCM solidifying MSWI FA, providing theoretical support for practical engineering. [ABSTRACT FROM AUTHOR]

The impact of operational conditions for carrying out methyl methacrylate suspension polymerization during stabilization of the system with dispersants of different chemical natures: poly-2-acrylamido-2-methylpropanesulfonic acid and Mg(OH)2, was studied. The role of the contribution of the chemical nature of the dispersant, which reduces the interfacial tension between the monomer and aqueous phases, to the particle size distribution of the polymer particles is shown. When polymerizing methyl methacrylate in the presence of water-insoluble Mg(OH)2, the interfacial tension diminishes, which brings about the formation of a highly dispersed polymer without the use of high-speed dispersion of the reaction mass. [ABSTRACT FROM AUTHOR]

In cold environments, the low temperature slows down microbial metabolisms, such as the biodegradation processes of hydrocarbons, which are often stimulated by the addition of dispersants in oil spill disasters. In this study, we investigated the effects of hydrocarbon water-accommodated fraction (WAF) prepared with and without dispersant on benthic microbial communities in a microcosm experiment in which hydrocarbon removal was observed. Both WAFs contained similar polycyclic aromatic hydrocarbon (PAH) content. The microcosm experiment, set up with either pristine or contaminated sediments, was conducted for 21 days at 4 °C under WAF and WAF + dispersant conditions. The behavior of bacterial communities in response to WAF and WAF + dispersant was examined at both DNA and RNA levels, revealing the effect of WAF and WAF + dispersant on the resident and active communities respectively. The contaminated sediment showed less taxa responsive to the addition of both WAF and WAF + dispersant than the pristine sediment, indicating the legacy effect by the presence hydrocarbon-degrading and dispersant-resistant taxa inhabiting the contaminated sediment. [ABSTRACT FROM AUTHOR]

Stereolithography-based additive manufacturing (AM) makes it possible to realize high-quality ceramic parts with various shapes. However, preparation of ceramic slurry with high solid loading, low viscosity, long-term stability, and desirable cure depth for stereolithography is still challenging. In this paper, research is carried out for revealing the effects of dispersant, solid loading, and mixing method on the stability and viscosity of the slurry. Under optimized conditions, a highly stable yttria-stabilized zirconia ceramic slurry with high solid loading (45 vol.%) was prepared by grinding with a three-roller mill. With layer thickness of 30 μm and exposure dose of 10 mJ/cm2 (10 mW/cm2 for 1 s), ceramic green bodies with complex shape were successfully fabricated. After sintering, the final ceramic parts showed well-defined shapes with high level of densification. [ABSTRACT FROM AUTHOR]

The application of chemical dispersants aims to stimulate microbial oil degradation by increasing the bioavailability of oil compounds. Overall, nine microcosms were prepared (three for each treatment) using treated sediment with (i) dispersant (d: 25 ppm), (ii) oil (500 ppm), and (iii) with oil + dispersant (500: 25 ppm), respectively. There are also three control microcosms containing only water and sediment without petroleum. Then, we analyzed bacterial abundance, total hydrocarbon, biological oxygen demand (BOD5), and chemical oxygen demand (COD) in each microcosm. Bacterial response density was significantly affected after 40 days of exposure; it was higher in the control microcosm and d (> 24.103 cell/l) than in the other treatments. The index of total hydrocarbons was equal to 53 mg/kg dw in oil and 56 mg/kg dw in oil + dispersant. The higher BOD5 found in oil and in oil + d shows the increased amount of oxygen consumed, which indicates enhanced bacterial activity. Microcosms treated with dispersant had higher COD than the others, but the dispersant did not stimulate microbial hydrocarbon degradation. [ABSTRACT FROM AUTHOR]

The market situation for depressant-dispersant additives for diesel fuel is discussed, the principal grades are listed, and methods for production of the depressant and dispersant components are presented. Information on a multipurpose depressant-dispersant additive designed at the Rosneft research and development RD Center, which improves the low-temperature, antiwear, and electrical behavior of diesel fuels is presented. [ABSTRACT FROM AUTHOR]

Oily sludge is a significant hazardous waste generated in the petroleum industry, and oily sludge reinjection and plugging is a new treatment technology developed in recent years, which is to reinjection oily sludge into the reservoir to plug channeling and improve the distribution of displacement front (profile conformance). However, there are many problems during oily sludge injection, such as high injection pressure or pump-block, due to the complex composition and poor suspension of oily sludge. Therefore, this paper proposes a dispersed oily sludge system, which can improve the stability and injectivity of the oily sludge by adding appropriate dispersants. The dispersants, a kind of interfacial active agent with strong lipophilicity and hydrophilicity, can greatly reduce the solid particle size and greatly improve the stability of the oily sludge by demulsifying the W/O emulsion and dispersing the solid particles. Through experiments, the optimal dispersant for oily sludge produced in Liaohe oilfield is AA/AMPS (Acrylic Acid and 2-Acrylamido-2-Methylpropane Sulfonic Acid Copolymer), and the optimal concentration of AA/AMPS is 1wt %. The oily sludge plugging experiments indicate that the raw and dispersed oily sludge have strong plugging ability, with the plugging rate exceeding 90% for the sandpack with permeability of 10000 mD. The dispersed oily sludge can greatly improve the injectivity of oily sludge, reduce the accidents in the injection process, and realize deep profile control, which is a potential in-situ treatment and application technology of oily sludge. [ABSTRACT FROM AUTHOR]

Oil pollution is today one of the main factors of the technogenic impact on the environment. Emergency oil spills are the main source of the oil pollution. The causes, scales, and environmental consequences of emergency spills are considered. The advantages and drawbacks of methods for eliminating the spills of crude oil and petroleum products on the surface of water bodies are discussed. The features of the sorption method for oil collection from the water surface, which is the most widely used method, are described in detail. Requirements to petroleum sorbents are analyzed, and classes of the sorbents are described. Synthetic polymer sorbents have a set of advantages over other types of oil-absorbing materials. Fighting emergency oil spills should include the activity aimed at their prevention. This is particularly topical for Russia, which starts active operation of the Northern Sea Route and of shelf deposits of fossil fuels in seas of the Russian Arctic. [ABSTRACT FROM AUTHOR]

The effect of the polyacrylate dispersant (AN-103P) on the electrical properties of ZnO varistors was investigated. With the increase of the dispersant content, the voltage gradient of the ZnO varistors increased, the leakage current decreased, the non-ohmic property first improved and then decreased, and the ratio of residual voltage under surge current to breakdown voltage (residual voltage ratio) gradually increased. To reduce the residual voltage ratio of the ZnO varistors, three different experiments were carried out to adjust the content of Sb2O3, the sintering temperature, and the content of Al3+, respectively. The results showed that increasing the content of Al3+ decreased the residual voltage ratio of the ZnO varistors most effectively. When the Al3+ content increased to 0.013 mol%, the ZnO varistors have the optimal comprehensive electrical performance with a voltage gradient of 321 V mm−1, and a residual voltage ratio of 1.76. This current capacity is higher than that of other reported varistors with similar gradients. [ABSTRACT FROM AUTHOR]

The colloidal silica is used as the abrasive for the copper Chemical Mechanical Polishing slurry in integrated circuit multilayer copper wiring. The aggregation of colloidal silica in the slurries tends to aggregate spontaneously, resulting in the continuous changes of the polishing effect, such as scratch defects, removal rate, etc. This situation can lead to the potential instability of the polishing slurry, which should be avoided in industrial production. In this paper, the aggregation and dispersion properties of polishing slurries were systematically studied, and an scheme was proposed to improve the dispersion of slurries to prevent agglomeration. These affecting factors including slurries' pH, Potassium nitrate and Sodium Polyacrylate were assessed with Large particle counts, Zeta potential and Particle size. Slurry's pH at 9.6 had a lower Zeta potential which meant a higher dispersion colloidal silica compared to other pH of slurries. And the dissolution of colloidal silica was verified by UV-vis experiment. Sodium dodecyl sulfate, Dodecyl trimethyl ammonium chloride and Primary Alcobol Ethoxylate-15 were analyzed for their dispersion in slurries from the point of view of static electricity and steric hindrance, and the synergistic mechanism of mixed Sodium dodecyl sulfate and Primary Alcobol Ethoxylate-15 on slurries dispersion was highlighted. In addition, the effect of the improvement of slurry dispersion on reducing scratching defects on the surface of polished copper blanket was also tested in this paper. [ABSTRACT FROM AUTHOR]

This paper reported a combination of powerful mechanical dispersion and chemical dispersion to solve the agglomeration of lithium iron phosphate (LiFePO4) fine powder in pulping process. The effect of the addition of dispersant fatty alcohol-polyoxyethylene ether (AEO-7) on the dispersibility of LiFePO4 slurry was compared, and the slurry prepared by traditional pulping process was also been compared. The dispersion uniformity of LiFePO4 particles and the rheological properties of the slurry were significantly improved with the addition of the dispersant AEO-7. The surface of the prepared electrode was regular, and the corresponding electrode showed a high compaction density. The LiFePO4 sample prepared with AEO-7 demonstrated excellent electrochemical performance of initial discharge capacities at 0.2, 0.5, 1, 2, and 5 C are 163.3, 160.9, 155.1, 146.2, and 126.5 mAh g−1, respectively. Furthermore, the14500 type steel shell battery prepared with different electrodes has also been studied. [ABSTRACT FROM AUTHOR]

The present work investigates the influence of surface-modified ferric chloride (FeCl3) nanoparticles mixed Cassia Fistula oil biodiesel blend (B20) for assessing combustion, performance, and emission parameters of diesel engine. FeCl3 nanoparticles were dispersed in three different concentrations as 50 ppm, 75 ppm, and 100 ppm. QPAN 80 dispersant was used as a dispersant to modify the surface of FeCl3 nanoparticles. The stability study of the prepared fuel dispersions was carried out for a period of one month using UV spectroscopy. B20 blend dispersed with FeCl3 nanoparticles has shown good stability. A tremendous improvement in engine operating parameters was seen with nanofuel and the injection pressure (IP) together. At higher IP of 220 bar, the brake thermal efficiency (BTE), cylinder pressure (CP), and net heat release rate (NHRR) were found to have improved by 3.14%, 5.81%, and 22.92% whereas the brake-specific fuel consumption (BSFC) was lowered by 3.89%. The emissions in terms of carbon monoxide (CO), unburnt hydrocarbons (UHC), nitrogen oxide (NOx), and smoke were noticed to have lowered by 42.68%, 9.73%, 14.68%, and 23.02%, respectively, for B20 + 75 ppm FeCl3 + 75 ppm dispersant as compared to regular diesel. [ABSTRACT FROM AUTHOR]

The fast hydration rate of aluminate makes the slurry of CaO–Al2O3-based mold flux coagulates fast, which hinders the production and large-scale application in steel plants. This study selected four dispersants and investigated their mechanism and influence on the dispersibility of CaO–Al2O3-based mold powder slurry. Main results showed that the stability of CaO–Al2O3-based mold powder slurry was poorer than CaO–SiO2-based mold powder slurry. The addition of non-ionic dispersant, OP-10 or glycerol, could make the viscosity of the CaO–Al2O3-based slurry become larger, and the macromolecule dispersant, Poly Vinyl Pyrrolidone, resulted in unstable variation of the viscosity of the mold powder slurry. The anionic dispersant, tannic acid, performed well, as it was able to release negative charges covering the powder particles, and the electrostatic repulsion made the aggregation among particles difficult to occur. The 5 wt% addition of tannic acid was found to effectively improve the dispersion of the CaO–Al2O3-based slurry. [ABSTRACT FROM AUTHOR]

The heat release kinetics in thermally initiated polymerization of 1,4-diethynylbenzene suggested as fuel dispersant in gas generator engines was studied under isothermal conditions in the temperature interval 90–150°С in the melt–vapor two-phase closed system. The enthalpies and entropies of melting, vaporization, and sublimation of 1,4-diethynylbenzene and the kinetics of a decrease in its vapor pressure in the course of polymerization in the melt were determined. Specific features of pressure and temperature variation in the course of propagation of the 1,4-diethynylbenzene combustion front in a cylindrical specimen in a Crawford bomb at the initial pressure of 2 MPa were studied. [ABSTRACT FROM AUTHOR]

The present work intends to know the nanoparticle stability in biodiesel blend (B20) and the combustion analysis of direct injection, single-cylinder, diesel engine. The aluminum oxide (Al2O3) nanoparticle additive with QPAN 80 dispersant (DSP) was mixed in B20. The nanoparticle was added in B20 at a proportion of 50 ppm together with 100 ppm dispersant. The test fuels considered were as follows: D100 (pure diesel), B20, B20Al2O350, and B20Al2O350DSP100. The combustion parameters, namely, cylinder pressure, net heat release rate, and mean gas temperature, were assessed. The fine improvement in the combustion characteristics was observed upon nanoparticle (50 ppm) addition to B20. However, the dispersant (QPAN 80)-mixed nanoparticle in B20 revealed tremendous enhancement than base nanoparticle addition. The maximum improvement of cylinder pressure, net heat release rate, and mean gas temperature was noticed as 15.16 %, 17.87 %, and 21.5 %, respectively, for B20Al2O350DSP100. [ABSTRACT FROM AUTHOR]

The features governing the high-rate thermal transformation (combustion without air access) of several dispersants (high-enthalpy N-heterocyclic compounds) were experimentally studied. The quantitative regularities of the combustion of both individual dispersants and their mixtures with isoprene rubber and ammonium perchlorate were examined. The dependences of consumption of individual dispersants on the nitrogen pressure, enthalpy of formation of the dispersants, and oxygen supply coefficient of the dispersant were determined. The dependences of the combustion rate on the contents of isoprene rubber and ammonium perchlorate were experimentally determined for the fuel compositions based on each dispersant. The results of the study can be used for the formation of optimal gas-generating fuel compositions. [ABSTRACT FROM AUTHOR]

This paper examines the effect of dispersant and anti-wear additives on fretting wear in lubricated bearing steel contacts. Reciprocating sliding ball-on-flat fretting tests with a stroke length of 50 μm have been carried out on steel-to-steel contacts in both dry and lubricated conditions. Wear and friction coefficient have been measured, and surface characterisation has been carried out using optical techniques to investigate fretting wear. The presence of base oil reduces fretting wear markedly compared to dry conditions, but fretting damage is still observed at low reciprocation frequencies. As frequency is increased, there is a transition from oxidative to adhesive/scuffing damage. The anti-wear additive ZDDP is effective in forming a tribofilm on the surfaces and reducing visible oxidation and wear. A succinimide dispersant also reduces the accumulation of solid debris but does not alleviate wear damage. The combination of both ZDDP anti-wear additive and dispersant in base oil appears to provide significant protection against fretting wear. [ABSTRACT FROM AUTHOR]

The efficiency of using seven cubane derivatives as dispersing components of solid generator propellants was studied. With cubane, bicubyl, or 1,4-dicubylbenzene used as a propellant dispersant, the aerial vehicle range can be increased to the level considerably exceeding the range reached with other compounds considered for this purpose previously. The use of nitro derivatives of cubane such as 1,4-dinitrocubane, 1,3,5,7-tetranitrocubane, 1,2,3,5,7-pentanitrocubane, and 4-bis(nitroxymethyl)cubane ensures somewhat shorter range than that reached with cubane, bicubyl, or 1,4-dicubylbenzene, but this range is still somewhat longer than when using furazan derivatives as dispersants. [ABSTRACT FROM AUTHOR]

In this study, a novel preparation route of shells for investment casting was proposed. To this end, hydroxypropyl methylcellulose (HPMC) was used as fiber dispersant, and its influences on rheological behaviors of slurry and strength of shell were studied. The addition of carbon fibers with different lengths and concentrations was also explored. The results suggested that suspension and viscosity of the slurries with HPMC were higher than those prepared without HPMC due to dispersion and tackily effects of HPMC on fibers and slurries. The fibers were found uniformly dispersed in the slurry, and fracture shell was uniformly distributed in the shell thanks to the presence of the dispersant, leading to enhanced shell strength. In addition, higher firing temperatures led to denser shell and superior strength. [ABSTRACT FROM AUTHOR]

Nowadays, although dispersants have been widely applied for emergency response to oil spills, they are potentially hazardous to the marine ecosystem. Therefore, it is necessary to evaluate dispersants' toxicity in a practical and integrated way before their large-scale application. Here, we compared the acute toxicity of five chemical dispersants (concentrate RS-I, conventional RS-I, HLD-501, Fuken-2, and Weipu) to three species (a microalgae Platymonas helgolandica, a mollusk Ruditapes philippinarum, and a luminescent bacterium Acinetobacter sp. Tox2) which represent different trophic levels. Our results showed that (1) conventional RS-I was slightly toxic to all the three test organisms; (2) concentrate RS-I and Weipu were slightly toxic to R. philippinarum, but were not toxic to the other two test species; (3) Fuken-2 and HLD-501 exhibited no acute toxicity to the three test organisms. Our results could provide information on toxicity data derived from multiple test organisms for the use of these five dispersants in the future. [ABSTRACT FROM AUTHOR]

The polyol method was implemented to prepare stable V–ZrSiO4 suspensions as ceramic ink. It was shown how the rheology, surface tension, viscosity, and particle size of suspensions were affected by the length of polyol solvent and dispersants. The effect of ethylene glycols, diethylene glycol (DEG), triethylene glycol, and tetraethylene glycol as solvents, as well as polyvinylpyrrolidone (PVP) and cetyltrimethylammonium bromide as dispersants on the ink properties was investigated. The X-ray diffraction, Fourier-transform infrared (FTIR), electron microscopy (FESEM/TEM) and dynamic light scattering analyses were performed to characterize the features of nanopigments. Crystalline V–ZrSiO4 nanopigment was obtained at 1100°C by DEG solvent in the presence of PVP. The sizes of the resulting nanoparticles were in the range of 10–50 nm. The achieved suspensions were tested as ceramic inks on a tile, and the colorimetric CIELAB parameters were measured. The CIE L*a*b* values confirmed the blue color. The surface tension and viscosity of prepared ceramic ink, as well as microstructure of the annealed nanopigments, were in the range required for drop-on-demand inkjet printers. [ABSTRACT FROM AUTHOR]

The baffled flasks were used to simulate regular wave and breaking wave at different oscillation intensities to study the effects of wave strength, reaction time, and dispersant on the submergence of oil spill. It was found that the wave strength has the greatest impact on submerging rate and submergence stability of Liaohe crude oil and Fuel 180. The characteristics of the impacts of the wave strength and dispersant content are that there are thresholds, below which the impacts are not obvious; their coupling effects are obvious only when both the wave strength and the dispersant content exceed their threshold; the impacts can accumulate over time and have the maximum value; the submerging rate reaches maximum at 30 min for Liaohe crude oil and 60 min for Fuel 180; the submerging rate will decrease after the time of the maximum impact. Based on the experimental results, it is proposed that the submerging model should have different forms based on the thresholds of conditions and different phases of the time, which need more work to be determined for different oils. [ABSTRACT FROM AUTHOR]

About 50 fuel formulations based on boron, hydrocarbon binder, and high-enthalpy polynitrogen dispersant were considered. The quantitative dependence of the reachable aircraft range with the optimized fuels on the elemental composition of the dispersant, its enthalpy of formation, and density was examined. The quantitative dependences of the aircraft range on the content of each element constituting the dispersant were obtained, and differences in these quantities were accounted for. Empirical formulas relating the flight range to the above characteristics of the dispersant were obtained; they allow prediction of the ballistic performance of the dispersants (including compounds that have not been synthesized by now) with an error no higher than 1%. [ABSTRACT FROM AUTHOR]

Dispersants including Tween 20, Tween 40, Tween 60, and polyacrylic acid (PAA) were used to modify nanoscale zero-valent iron (nZVI). All dispersants dispersed nZVI effectively. PAA-modified nZVI was more stable than nZVI that was modified with Tween surfactant. Iron nanoparticles that were prepared using 0.5–5.0% (vol%) of PAA remained in suspension for more than 2 h. nZVI that was modified using Tween surfactant remained in suspension for 30–60 min, and there was complete sedimentation of bare iron in 10 min. When 2.0–5.0% (vol%) of Tween surfactant was used, the stability of the nZVI that was modified using Tween 20 was much better than that for nZVI that was modified using Tween 40 or Tween 60. The results for the transportation test show that nZVI that was prepared using 2% (vol%) of Tween 20 exhibited the best mobility in porous media. Approximately 83–90% of TCE was degraded by bare, PAA-modified, and Tween 20-modified nZVI, and about 63–67% of TCE was removed by nZVI that was modified using Tween 40 and Tween 60 during 20 days of reaction. The production of cis-dichloroethene (DCE) and 1,1-DCE demonstrates that TCE is removed via reductive dechlorination. The results of this study show that PAA- and Tween 20-modified nZVI are more practical for in situ remediation because they exhibit good mobility and degrade TCE effectively. [ABSTRACT FROM AUTHOR]

The energy of combustion ΔH°c of 4H,8H-bis(furazano)[3,4-b:3′,4′-e]pyrazine (BFP) was measured by calorimetry in the oxygen atmosphere and the standard enthalpy of formation ΔH°f was calculated. The real ΔH°f value was found to be 33 kJ mol−1 higher than reported before. The obtained results were used for correction of the evaluated efficiency of using BFP as a solid fuel dispersant for rocket ramjet engines, which showed high BFP performance. [ABSTRACT FROM AUTHOR]

The possibility of replacing the currently widely used ammonium perchlorate as an oxidizing agent (dispersant) in the composition of solid boron-containing fuels for aircraft with rocket ramjet engine was considered by dispersants with reduced nitrogen and oxygen content with a high enthalpy of formation (more than 2 MJ kg−1) and capable of gasifying solid fuels. The efficiency of fuels with high enthalpy dispersants was evaluated in an optimization setting according to the flight range criterion of the aircraft taking into account the complete combustion of fuel in the afterburner chamber. A number of the most effective dispersants were recommended for further study. [ABSTRACT FROM AUTHOR]

Purpose: The present study evaluated the effects of Superdispersant-25 (SD25), a commercial dispersant stockpiled in the UK for oil spill response, on the sorption dynamics of two polyaromatic hydrocarbons, naphthalene (NAP) and phenanthrene (PHE), in sediment-seawater systems using three sediments near hydrocarbon exploration areas in the Faroe-Shetland Channel and North Sea.Materials and methods: Batch experiments were conducted to evaluate the effects of SD25 on the solubility (analysed by gas chromatography), distribution coefficients and desorption hysteresis of NAP and PHE separately as well as SD25 in the three sediments (analysed by UV-vis spectroscopy and surface tension measurements, respectively).Results and discussion: The results revealed that SD25 readily adsorbed to all sediment types but did not desorb from silty loam. SD25 application increased the solubility in seawater of PHE but not of NAP. Adsorbed SD25 increased the distribution coefficients of both polyaromatic hydrocarbons in sand but not silty loam and the solubilising effect of SD25 appeared to drive increased adsorption of PHE rather than sediment-adsorbed SD25 concentration.Conclusions: The findings highlight the influence of SD25 application on the sorption dynamics of NAP and PHE in marine sediments from areas near hydrocarbon exploration and production regions. An understanding of these interactions may aid responders in the decision-making process of dispersant application in the event of a spill as seabed characteristics affect oil-dispersant-sediment interactions. [ABSTRACT FROM AUTHOR]

In this study, pentlandite was selectively separated from serpentine using magnetic coating technology by adjusting and optimizing pH, stirring speeds, magnetic field intensities, and dosages of sodium hexametaphosphate (SHMP) and sodium oleate (SO). A magnetic concentrate with Ni grade of 20.8% and Ni recovery of 80.5% was attained under the optimized operating conditions. Considering the above, the adsorption behaviors of SHMP and SO and the surface properties of minerals after the magnetic coating were studied by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results show that magnetite was preferentially coated on the pentlandite surfaces and sparingly coated on the serpentine surfaces in the presence of SHMP and SO. Furthermore, calculations by Derjaguin-Landau-Verwey-Overbeek (DLVO) theory indicate that the preferential adsorption of magnetite on the pentlandite surfaces is due to the presence of a hydrophobic interaction between the magnetite and pentlandite, which is much stronger than the interaction between magnetite and serpentine. [ABSTRACT FROM AUTHOR]

Oil spills in the marine environment can cause ecosystem-level impacts. Dispersant application as an oil spill response measure leads to the widespread distribution of hydrocarbons in the water column and marine sediments. The North Sea is an area of intense hydrocarbon production and is at risk of oil spills, which are of concern to its benthic ecosystem due to its sediments’ high permeability. Here, entrainment of hydrocarbons via pore-water advection into permeable North Sea sands and the associated effect of Superdispersant-25, a commercial oil dispersant, were evaluated in a laboratory. Centrally stirred chambers that induce advective pore-water fluxes in sediments were filled with sediment, seawater and mixtures of oil and Superdispersant-25. Dispersant application had contrasting effects on hydrocarbon interactions with sediment: (1) it reduced accumulation of hydrocarbons in surface sediments and (2) facilitated the entrainment of hydrocarbons up to 8 cm deep into sediments by increasing hydrocarbon solubility in seawater and its subsequent washout or pumping into sediment by pore-water movement. Results here show that dispersant application can have counter-intuitive effects on hydrocarbon interactions with marine sediments and highlight the need for further research in this area to make better informed decision in an oil spill response scenario. [ABSTRACT FROM AUTHOR]

Various branched polymers with different functionalities and side chains were synthesized as dispersant and their molecular structures were characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance, and thermogravimetric analysis (TGA) methods. It was found that the amount of side chain and kind of acidic or ionic functions had influences on the properties of the dispersants. The effect of side chain density of the dispersants on the intercalation of sodium montmorillonite (Na-MMT) was also investigated. The results of X-ray diffraction, and FTIR and TGA analyses showed that the branched polymers with a higher amount of side chains and acidic functions were suitable to provide efficient intercalation and adsorption. In addition, a weak intercalation of dispersant with a lower side chain density and neutral functions into the Na-MMT interlayer was observed. The role of side chain density and acidic/neutralize functionalities of dispersants on both the yield stress and viscosity of reactive silica fume suspensions was investigated. It was found that the dispersant with acidic functionalities and low amount of side chains increased the yield stress and viscosity. A lower viscosity was also recorded for the suspensions in the presence of Na-MMT. Moreover, the suspension prepared by the dispersant with a high side chain density exhibited higher fluidity and lower viscosity. [ABSTRACT FROM AUTHOR]

This study focused on comparing the lethal and sublethal toxicity of water-accommodated fractions (WAF) and chemically enhanced WAF (CEWAF) of crude oil to zebrafish (Danio rerio) on early life stages (ELS). Results showed that the addition of GM-2 dispersant caused an increase in the levels of total petroleum hydrocarbons (TPHs) and total priority polycyclic aromatic hydrocarbons (ΣPAHs). Based on ΣPAHs, the LC20 estimates for WAF and CEWAF were 4.88 µg L−1 and 1.19 µg L−1, respectively, indicating that CEWAF was approximately four times more toxic. CEWAF exposure caused markedly lower hatching rates and higher malformation frequencies than WAF. Meanwhile, the general morphology score (GMS) values in CEWAF were about fourfold lower than that in WAF, indicating that CEWAF exposure induced more significant developmental delay. The results suggested that chemical dispersant enhanced the toxicity of crude oil to zebrafish on ELS and its application could increase the exposure of fishes to crude oil. [ABSTRACT FROM AUTHOR]

The possibility and feasibility of nanocrystalline cellulose (NCC) for dispersing hydrophobic graphene in aqueous solutions were studied in the present work. The dispersion properties of graphene particles in aqueous media as a function of various amounts of NCC were investigated. The rheological behavior of NCC-dispersed graphene suspensions was studied, and a polynomial model was proposed and employed to simulate the obtained shear flow of graphene suspensions. The results of UV-Vis analysis and sedimentation test suggested that the increased NCC addition significantly led to the improved dispersion properties of graphene suspensions. Rheological behavior measurements demonstrated that graphene suspensions exhibited a reduction trend in the shear viscosity, shear stress, and viscoelasticity with the increased amount of NCC addition. Meanwhile, the shear viscosity and shear stress of graphene suspensions were found to show a dependency on the process temperature. The above results supported the conclusion that NCC is a promising candidate for improving the dispersion and flowability of graphene in aqueous media. [ABSTRACT FROM AUTHOR]

In this study, shrimp waste was enzymatically hydrolyzed to generate a green dispersant and the product was tested for crude oil dispersion in seawater. The hydrolysis process was first optimized based on the dispersant effectiveness (DE) of the product. The functional properties of the product were identified including stability, critical micelle concentration, and emulsification activity. Water was confirmed as a good solvent for dispersant generation when compared with three chemical solvents. The effects of salinity, mixing energy, and temperature on the dispersion of the Alaska North Slope (ANS) crude oil were examined. Microtox acute toxicity test was also conducted to evaluate the toxicity of the produced dispersant. In addition, DE of the product on three different types of crude oil, including ANS crude oil, Prudhoe Bay crude oil (PBC), and Arabian Light crude oil (ALC) was compared with that of the Corexit 9500, respectively. The research output could lead to a promising green solution to the oil spill problem and might result in many other environmental applications. [ABSTRACT FROM AUTHOR]

Many attempts has been taken for further utilisation of the tailings and slimes through different routes i.e. beneficiation, agglomeration etc. Though the slimes and tailings contain huge ultra fines, conventional beneficiation methods many not be much effective for handling because of particle size limitations. Physicochemical method i.e. selective flocculation is a process for handling the ultrafine particles present in the tailings. Review shows that selective flocculation technique have very limited commercial application. Here the study focuses on the application of selective flocculation process for beneficiation of synthetic mixtures of iron ore and kaolinite as well as iron ore tailings. Results show that it is possible to achieve 65.78(%) of Fe, with 2.65% Al2O3, 3.66 SiO2 (%) in the concentrate using synthetic mixture feed and more than 60% of Fe is obtained from natural iron ore tailings. [ABSTRACT FROM AUTHOR]

To protect forest resources and increase the value of agro-industrial residues, it would be helpful to produce paper-based materials from non-woody or recycled fiber resources. This study investigated the reinforcement mechanism of bacterial cellulose (BC) on paper sheets made from different sources including softwood, hardwood, sugarcane bagasse, bamboo, wheat straw, and recycled fiber, which represent a selection of high quality, medium quality, and low quality fibers. The results showed that by maintaining BC addition at a low level of 0.5-1.5% (total paper dry weight), the paper sheets made from high and medium quality fibers have the maximum tensile index improvement, with 5-25%. The tensile index of low quality fiber including wheat straw pulp and recycled fiber pulp increased slightly and gradually with the level of BC addition; at 5% BC addition, the tensile indexes increased by 9 and 40%, respectively. To investigate the BC reinforcement mechanism, different fiber characteristics, SEM images of BC reinforced paper, BC retention rate on paper, and the effects of dispersant addition were evaluated. It was found that high BC addition or retention rate in paper sheets do not necessarily result in good BC reinforcement effects but that proper dispersion of BC is important. [ABSTRACT FROM AUTHOR]

The flow behavior of a filled suspension consisting of ferrite particles suspended in a polypropylene matrix with and without the addition of a commercial dispersant (Solplus DP310) was studied. The composites were filled with 10, 20, 30, and 40 vol.%. Both capillary and parallel disk rotational flows were employed. On the one hand, dynamic results confirm general trends found for highly concentrated systems. The higher is the filler level, the lower is the linear viscoelastic domain. When adding the dispersant agent, it was shown a larger linear viscoelastic domain, lower moduli values and thus, lower viscosity. Also, the critical strain, G′ and G′′ showed a power law dependency on the volume fraction. On the other hand, the capillary results showed no dependency of the flow properties on the die. Thus, no slip of the suspension at the wall was observed. Actually, this experimental finding elucidated that the significant decrease on viscosity produced by the addition of the dispersant agent at 40 vol.% is principally due to lubricant effects and not at all to slip contributions. The results also reveal three distinct flow regimes. Low, moderate, and high shear rates lead to different microstructure under flow. [ABSTRACT FROM AUTHOR]

Nanocarbon-coated graphite with high resin and water wettability characteristics can expand the application of refractories and carbon-carbon composites in different fields. Flaky graphite was made water wettable by coating nanocarbon on the surface of graphite by using suitable surfactants and dispersants. The coated graphite characteristics were confirmed by XRD, FESEM and HRTEM, which show that nanocarbon is coated on the graphite and it has the same nature as natural graphite. This developed coated graphite has wide applications in refractory brick, castables and masses for application in the steel industry. MgO-C bricks with lower (3 mass-%) carbon content, with nanocarbon-coated grains and coated graphite, have led to better properties than normal higher (10 mass-%) graphite containing bricks. Uniform distribution of graphite in the matrix is possible by using this developed graphite. [ABSTRACT FROM AUTHOR]