AbstractChanges in the dispersion state of heavy fuel oil with dissolved hydrogen sulfide, occurring under the action of low-energy wave treatment, were studied. Treatment with ultrasound and constant magnetic field ensures the reduction of the hydrogen sulfide content of the fuel oil to less than 10 ppm, and even to 1 ppm when the treatment is combined with using absorbents. The optimum parameters of the wave treatment were determined. The mean particle diameter of the dispersed fuel oil phase passes through a maximum in the course of wave treatment. The mechanism of processes occurring in the course of hydrogen sulfide removal from heavy fuel oil, based on concepts of petroleum disperse systems, was suggested.

AbstractThe performance of polyalkyl acrylate additives of various compositions in low-temperature dewaxing of 11 oil fractions differing in the viscosity and content of waxes, aromatic hydrocarbons, and resins was studied. The dewaxing was performed in a methyl ethyl ketone–toluene mixed solvent. For polyalkyl acrylate with pendant C16–10 alkyl chains, the raffinates can be subdivided into three groups with respect to an increase in the yield of dewaxed oils (relative to the process without additives): increase by 12–13, 5–8, and 3–4%. In most cases, introduction into such polymer of 5–30% polar groups (amino ester, amino amide, amide, oligoethylene glycol) allowed the oil yield to be additionally increased.

AbstractThis review describes a process for methanation (selective hydrogenation) of carbon oxides with an emphasis on its importance for environmentally friendly and distributed energy generation. The drawbacks of oxide-supported catalysts and the advantages of carbon-based catalysts are assessed in terms of green chemistry principles. Catalysts based on carbon nanotubes, carbon nanofibers, and biomass derivatives are further discussed. Major research approaches are outlined for the implementation of carbon-based catalysts in selective hydrogenation of carbon oxides. This discussion suggests that the most promising catalysts for methanation are those based on biomass-derived carbon materials.

AbstractThe present study assessed the effects of the lithological composition of the Western Siberia permafrost zone on the concentrations of methane (and its homologs), olefins, and hydrogen. This permafrost zone is distinguished by inhomogeneous distribution of hydrocarbon and non-hydrocarbon components across the area and section. The conclusions are based on chromatographic analysis of 199 samples from six core holes located in a multilayer gas condensate field in the Nadym district of the Yamal-Nenets Autonomous Okrug, in the continuous permafrost zone. To minimize external impacts, the core from shallow core holes was used. The core samples were degassed and analyzed chromatographically for hydrocarbons (C1–C8) and non-hydrocarbon gases (H2, CO2, and He). Based on the lithological composition and the concentrations of individual components in the core holes, an interhole correlation was obtained with the distribution of parameters. The gas concentrations were shown to almost unavoidably decrease at lithological interfaces, and this decrease has no effect on the distribution of the components within individual beds, i.e. these components do not accumulate in significant amounts. Because this phenomenon cannot by described by the geochemical barrier concept, a new concept of “geochemical shield” is suggested.

AbstractThe influence of the phase composition of the dispersed molybdenum catalyst on the transformation of high-molecular-mass components (resins and asphaltenes) in the course of hydroconversion of heavy petroleum feedstock was studied. Suspensions of catalyst particles were prepared from inverse emulsions of aqueous solutions of the precursor, ammonium paramolybdate, directly in the feed in the course of hydroconversion (in situ), or the catalyst suspension was synthesized in advance (ex situ) and then was added to the feed. The vacuum residue from petroleum distillation and heavy crude were used as the feedstock. Experiments were performed in a flow-through reactor under the conditions of hydroconversion with the addition of a sulfur donor to the feed. Catalyst particles with different ratios of the Mo sulfide and oxide phases were prepared ex situ. With an increase in the МoS2 content of the dispersed catalyst, its activity in inhibition of chain reactions of thermal cracking, yielding resins, asphaltenes, and coke, increases. The conversion of the >500°С fraction in the presence of the catalyst decreases; this is probably due to saturation and neutralization with active hydrogen of primary radicals that are generated in the course of thermal degradation, initiate the chain reaction of thermal cracking, and favor its propagation.

AbstractSupported catalysts Mo/Al2O3 in which the support was modified with additions of (NH4)2SiF6 and H3BO3 were synthesized and tested in metathesis of propylene to ethylene and butylenes. The samples obtained were studied by low-temperature nitrogen adsorption–desorption, X-ray fluorescence analysis, energy-dispersive X-ray analysis, temperature-programmed NH3 desorption, and in situ Raman spectroscopy. The support modification with (NH4)2SiF6 does not alter the acid properties of the final catalyst, whereas the interaction of γ-Al2O3 with boric acid leads to an increase in the total acidity of the final catalyst. Modification of the support both with (NH4)2SiF6 and with H3BO3 appreciably enhances the catalyst activity but favors its faster deactivation.

AbstractThis study demonstrates the potential for computer-aided engineering and additive manufacturing techniques to fabricate protective layer materials with a novel design of filtration channels. Using computational fluid dynamics (CFD) simulation for channels of various geometries, potential locations of the capture of solid dust particles in ceramic filter pellets were identified. The filter pellets were fabricated from ceramic material using laser stereolithography. The printed samples were subjected to a filtration test. The CFD simulation of the pellet channels to identify potential filtration locations, followed by a comparative assessment of the simulation results and the post-test X-ray computed tomography (CT) scan of the 3D-printed pellets, demonstrated the feasibility of CFD models for the design of filter materials. The study findings are intended for the development of innovative protective materials with filtering capabilities to be implemented in specific industrial refining applications.

AbstractThe paper proposes a method for synthesizing a heterogeneous catalyst that contains single Pd sites on γ-Al2O3 surface. This method involves preliminary heterogenization of a Pd complex with a hydroxyquinone (e.g., alizarin) on the γ-Al2O3 surface, followed by hydrogenolysis of the Pd–alizarin bond, reduction of Pd(II) into Pd(0), and removal of alizarin. The catalyst was examined by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and tested in propane oxidation into key petrochemicals. During the test, the catalyst exhibited high activity (242 mol of the product per g-at Pd per hour).

AbstractTorrefaction and hydrothermal carbonization are low-temperature thermochemical procedures for the biomass conversion to biocoal, a carbon-neutral analog of fossil coal. Biocoals, compared to untreated biomass, exhibit hydrophobic properties, increased energy density, and calorific value similar to that of brown coals. The two processing methods differ essentially in that hydrothermal carbonization is performed in the presence of a large amount of water as reaction medium; hence, the biocoal formation mechanisms will be different for each process. Papers dealing with specific features of low-temperature heat treatment of biomass and with regular trends in conversion of biomass structural components (cellulose, hemicellulose, lignin) in the course of torrefaction and hydrothermal carbonization are considered in the review.

AbstractThe paper describes an investigation of lubricants synthesized by thickening a dispersion medium consisting of silicone oil (PES-5) and poly-α-olefin oil (PAOM-12) with diureas of different compositions. The study revealed the effects of the compositions both of the dispersion medium and urea thickener, as well as their ratio in the lubricating formulation, on the major physicochemical properties of resultant greases. Increasing the content of the hydrocarbon component of the grease was shown to improve the physicochemical properties. Finally, the optimum grease composition was identified: introducing a polyurea thickener that contained diphenylmethane-4,4'-diisocyanate resulted in the synthesis of greases that had adequate operating characteristics and an improved wear performance.

AbstractFlow assurance is one of the main challenges in the oil industry. Many factors can affect the oil fluidity, including the oil °API and the formation of water-in-oil (w/o) emulsions that increase the fluid viscosity. The demulsification process aims to decrease as much as possible the water content in the crude oil. Chemical products known as demulsifiers can be used to aid in this process. In laboratory, the chemicals can be evaluated under temperature and water content conditions similar to those in the oil field. In this work, the effect of demulsifier aging on its performance, simulating oil field storage, was evaluated using synthetic w/o emulsion prepared with a heavy crude oil and brine at 55 000 ppm. The crude oil was characterized and some demulsifier properties were measured along the time. The crude oil was identified as a heavy oil containing 11.6% of asphaltenes, contributing to the w/o emulsion stability. The demulsifier performance increased with aging time, and the results strongly suggested that a mere evaporation of the additive solvent occurs, concentrating its active matter.

AbstractThe enzyme under study, namely β-galactosidase from Aspergillus oryzae fungi, adsorbed on the surface of BEA and MFI zeolites retained about 17–20% of its initial catalytic activity. The Michaelis constant increased by a factor of 1.5–2. When heated, the enzyme exhibited higher stability on zeolite surfaces than in solution. At 57°C the effective denaturation rate constants of the adsorbed enzyme ranged between 2.9×10–5 and 5.7×10–5 s–1, compared to 1.7×10–4 s–1 for the enzyme in a neutral aqueous solution and 3.5×10–4 in a buffer (pH 7.5). When heated to 60°C, the enzyme denaturation rate increased about threefold. The highest adsorption capacity was achieved on a fine-crystalline sample synthesized in an alkaline medium.

AbstractA series of experiments on interzeolite transformations of FAU into MFI was carried out. The study investigated the effects of various parameters, such as the chemical composition of parent zeolite, presence and type of seed crystals, and recrystallization method, on the physicochemical properties and catalytic performance of the MFI zeolites produced by interzeolite transformation from FAU. This enabled the researchers to optimize the transformation conditions and to propose highly efficient methods for targeted template-free synthesis of MFI zeolites with specific physicochemical properties and specific types of active sites. Based on a comprehensive analysis of the above-mentioned parameters governing the properties of target zeolites, a number of high-performance catalysts for methanol-to-hydrocarbon conversion were synthesized without templates, their catalytic performance being effectively controlled within a wide range.

Erratum

AbstractThe study investigates tert-butoxy alkanols (otherwise defined as polyol tert-butyl ethers) that have vicinal tert-butoxy and hydroxy groups in their molecules from the perspective of their usability as oxygenated additives for motor gasoline. A series of propylene glycol mono-tert-butyl ether (PTBE) and glycerol di-tert-butyl ether (di-GTBE) samples were prepared: PTBE by direct acid-catalytic alkylation of diols with tert-butanol, and di-GTBE by alkylation of epichlorohydrin. Adding PTBE and di-GTBE to base motor gasoline was found to improve its antiknock performance: the average blending research octane number to blending motor octane number ratios (bRON/bMON) equaled 120/111 and 124/104 for PTBE and di-GTBE, respectively. Furthermore, the effects of the ether additives on the properties of ethanol-blended base gasoline were characterized. Finally, the study describes the effect of polyol tert-butyl ether additives on the cloud point depression of ethanol-blended gasoline (low-temperature phase stabilization) and demonstrates a positive synergistic effect of adding the ethers mixed with ethanol.

AbstractIn this work, a multicomponent demulsifier package (named BDTXI) was developed for increasing the demulsification performance of the water-in-oil emulsions. Optimized demulsifier formulation consists of three active components (1-butyl-3-methylimidazolium bis (trifluoromethylsulfonyl)imide, dodecyltriemthylammonium chloride, trioctylmethylammonium chloride), xylene, and isopropanol. A positive synergistic effect was observed among the active components of BDTXI. The concentrations of the components of the developed demulsifier package are determined based on obtaining the best synergistic effect. The demulsification efficiency of BDTXI was higher than commercial reagents at any concentration, water content, and temperature. The optimal concentration of BDTXI was 50 ppm, at which its demulsification effectiveness was more than 97%. The developed demulsifier package could adsorb at the oil-water interface, promote the colloidal dissolution of the emulsion layers, and form a hydrophilic surface characterized by a weak structural strength. The demulsification mechanism of BDTXI was based on minimizing the interfacial tension in order to be able to break the film and increase the frequency of droplet collisions. The change in the temperature and water content of the emulsions did not affect the demulsification performance of BDTXI. Moreover, the average reduction in the asphaltene flocculation parameter with the use of BDTXI and commercial reagents was about 19 and 11%. The results of the analysis of the backscattering light intensity, turbiscan stability index, zeta potential, and shear rate of the emulsions in the presence of various demulsifiers showed that BDTXI could separate the water in the emulsions more efficiently and faster than the commercial reagents.

AbstractA series of tubular porous ceramic converters modified with mono- and bimetallic catalytic systems based on rhenium and tungsten were prepared by a combination of self-propagating high-temperature synthesis and the sol–gel method. These converters were tested in dehydrogenation of ethylbenzene to styrene. Among the tested samples, a monometallic tungsten-containing converter exhibited the optimal properties as it achieved the highest target product production performance. Within the temperature range of 550–600°C, this converter provided a yield of styrene up to about 15 wt % and styrene productivity up to about 22 g h–1 dm–3, with the carbonization of the sample not exceeding 5 wt % over about 6 h of reaction.

AbstractS Zorb process is one of the main technologies for deep desulfurization of gasoline from fluid catalytic cracking (FCC) process, which by the process will also cause some research octane number (RON) loss of gasoline. Establishing a data-driven model with data mining technologies to optimize production is one of the development directions in petrochemical field. Based on the industrial data from a 1.20 Mt/a S Zorb unit in China in recent three years, 422 modeling samples and 22 modeling variables were screened out and then three data-driven models were established by back propagation neural network (BPNN), radial basis function neural network (RBFNN) and generalized regression neural network (GRNN) to predict RON of refined gasoline (r-RON). The results show that the BPNN model has the best prediction effect and generalization ability. Genetic algorithm (GA), particle swarm optimization algorithm (PSO) and simulated annealing algorithm (SA) in combination with the BPNN model respectively were used to optimize the operation variables to reduce the r-RON loss. The results indicate that the optimized performance of PSO-BPNN model is best because of its largest reduction in r-RON loss at 48.55%. The validity of the PSO-BPNN model was verified in the S Zorb unit and the research methods to establish a data-driven model for reducing r-RON loss are also worthy of reference for other S Zorb units.

AbstractThree types of heterogeneous Fenton catalysts based on Fe-silicalite-1 were synthesized: (1) microcrystals with an average size of 5 μm (m-FeZ); (2) a hierarchical porous sample consisting of 100–200 nm nanocrystals prepared using a dry polystyrene latex template (h-FeZ); and (3) three hierarchical porous samples consisting of 30–50 nm nanocrystals prepared by steam-assisted crystallization (n-FeZ-1,2,3). The synthesis procedure for n-FeZ-1 and n-FeZ-2 included gel pretreatment at 90°C for 72 h. This pretreatment specifically involved introducing Fe into the reaction mixture after (for n-FeZ-1) and before (for n-FeZ-2) the gel aging. The samples were tested as heterogeneous Fenton catalysts in H2O2-mediated total oxidation of ethanol. The performance of the heterogeneous catalysts was compared with a conventional homogeneous Fenton catalyst.

AbstractThe paper describes a specifically developed novel samarium cobaltate/silicon carbide composite that transforms into a high-performance carbon-resistant catalyst for dry reforming of methane into syngas (DRM). This 30%SmCoO3/70%SiC composite without hydrogen prereduction was tested in DRM at atmospheric pressure and GHSV 15 L g–1 h–1 (of an equimolar CH4–CO2 mixture). During the test, the yields of hydrogen and carbon monoxide reached 92 and 91 mol %, respectively, at 900°C, and 20 and 28 mol % at 700°C. Using XRD, TGA, and SEM examination, zero carbonization of the catalyst surface was demonstrated. It was found that, in the course of DRM, the initial composite transformed into a material that contained silicon carbide, samarium silicate, and samarium oxide, as well as metallic cobalt nanoparticles (<20 nm).