Theoretical Foundations of Chemical Engineering最新文献

{"title":"Direct Numerical Simulation of Turbulent Thermal Diffusivity","authors":"Yu. G. Chesnokov","doi":"10.1134/S0040579525600226","DOIUrl":"10.1134/S0040579525600226","url":null,"abstract":"<p>The influence of the Reynolds and Prandtl numbers on the turbulent thermal diffusivity in a flat channel was studied. The data obtained by various research groups by direct numerical simulation were used. It was shown that the ratio of the turbulent thermal diffusivity to the molecular thermal diffusivity and to the Reynolds number calculated from the dynamic velocity is not a universal function of the dimensionless distance to the wall, as follows from the logarithmic formula for the temperature profile and the temperature defect law, but depends on the Reynolds and Prandtl numbers. Relationships were obtained that allow one to estimate this value at relatively large values of these parameters.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 4","pages":"1105 - 1111"},"PeriodicalIF":0.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extraction of Li(I), Al(III), and Fe(III) from Hydrochloric Solutions with Hydrophobic Eutectic Solvent TIBPS/Menthol","authors":"I. V. Zinov’eva,&nbsp;A. M. Salomatin,&nbsp;Yu. A. Zakhodyaeva,&nbsp;A. A. Voshkin","doi":"10.1134/S0040579525600263","DOIUrl":"10.1134/S0040579525600263","url":null,"abstract":"<p>A new hydrophobic eutectic solvent based on triisobutylphosphine sulfide (TIBPS) and menthol is proposed, its main physicochemical properties are studied, and its extraction capacity for Fe(III), Al(III), and Li(I) ions is assessed. For the TIBPS/menthol system, a solid–liquid phase diagram is constructed and the interaction between the components in the eutectic solvent is established using IR and NMR spectroscopy. The temperature dependences of the dynamic viscosity, density, and refractive index of the proposed eutectic solvent are established. The extraction of Fe(III), Al(III), and Li(I) ions from hydrochloric acid solutions using TIBPS/menthol is studied depending on the concentration of HCl and NaCl, the volume ratio of the phases, and the initial concentration of the metal. The temperature dependences of the degree of extraction of metal ions are obtained and an assessment of the thermodynamic parameters of extraction is carried out. The indices of re-extraction of Fe(III) ions from the organic phase with distilled water are determined and the degree of its extraction with repeated use of the eutectic solvent is established. The potential of using the proposed hydrophobic eutectic solvent for the extraction of metals from aqueous solutions is shown.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 4","pages":"1143 - 1154"},"PeriodicalIF":0.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of Clinoptilolite Zeolite and Investigation the Influence of Various Factors on the Crystallization Process in Natural System Obsidian-Halloysite","authors":"A. D. Abbasov,&nbsp;G. A. Mamedova","doi":"10.1134/S0040579524600347","DOIUrl":"10.1134/S0040579524600347","url":null,"abstract":"<p>The crystallization process of a practically important zeolite of clinoptilolite has been studied, which can be used as an adsorbent, catalyst. The influence of various factors on the speed and selectivity of synthesis using natural minerals obsidian and halloysite of Nakhchivan has been investigated. The starting material was a natural mineral of Nakhchivan—volcanic glass obsidian from the peak of Gapydzhik of Ordubad district and halloysite of Pirigel deposits. The influence of temperature of 100–250°C, the mass ratio of the initial components of halloysite (H) and obsidian (O) H : O equal to 1 : 1, 1 : 2, 1 : 3, 2 : 1 and 3 : 1, a concentration of a thermal solution of NaOH of 10–30%, the duration of the process is in the range of 10–50 h and the “aging” process on the crystallization of clinoptilolite were studied. It has been established that the optimal conditions for the synthesis of clinoptilolite with 100% crystallinity and phase purity is as follows: temperature 150 ± 2°C, concentration of thermal solution of NaOH of 15–20%, quantitative ratio of the initial components of halloysite (H) and obsidian (O) H : O, equal to 1 : 2, processing time—20 h. The synthesis of zeolite of clinoptilolite using natural minerals from the Nakhchivan Autonomous Republic was carried out in the presence of tetramethylammonium hydroxide (TMAOH). The effect of temperature, concentration of thermal alkali solution, ratio of initial components, process time, duration of “aging” on crystallization of clinoptilolite was studied. It has been shown that violation of optimal synthesis conditions leads to a decrease in the selectivity of the process and the formation of other zeolites (phillipsite, gismondine), aluminosilicates (anortithe, albite) or mixtures thereof, as well as quartz and cristobalite. The “aging” process was studied in the duration range from 1 to 3 days. It has been established that an increase in the duration of “aging” leads to an increase in the linear rate of crystallization of clinoptilolite zeolite.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 4","pages":"1206 - 1217"},"PeriodicalIF":0.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Electrodynamic Separation of Conducting Materials Using Inductors with a Variable Pole Pair Number","authors":"Yu. V. Afanas’ev,&nbsp;A. Yu. Demin,&nbsp;D. Yu. Pashali,&nbsp;O. A. Yushkova,&nbsp;A. I. Shaikhlislamov","doi":"10.1134/S0040579524601900","DOIUrl":"10.1134/S0040579524601900","url":null,"abstract":"<p>Systems for the automatic sorting of solid household waste and their disadvantages are analyzed. The work considers an original method for the electrodynamic separation of electrically conductive materials with the use of one or more inductors with a variable number of pole pairs to generate a traveling electromagnetic field that affects electrically conductive fragments (ECFs) of solid household wastes (SHW). In the course of separation, the inductor windings are switched in such a way that the pole division discretely changes from the maximum value to the minimum one, or vice versa, within a certain switching time range determined by the maximum inertia of electrically conductive fragments having a size close to the pole division value. The method for electrodynamic separation, as well as the control unit for the electrodynamic separation system, are described. The proposed method should make it possible to extend the functionality of automatic systems for sorting and processing electrically conductive solid household waste and may provide an increase in separation productivity.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 4","pages":"1218 - 1222"},"PeriodicalIF":0.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of Pump Stations for Contaminated and Aggressive Liquid Media Based on Digital Information Models","authors":"A. I. Repnikov,&nbsp;A. A. Yakovlev,&nbsp;M. P. Kukhtik","doi":"10.1134/S004057952460195X","DOIUrl":"10.1134/S004057952460195X","url":null,"abstract":"<p>An informational description of a pump station for contaminated and aggressive liquid media is given. The stages of design of stations using a digital information model and a scheme for using the model in design are presented. An algorithm for designing pump stations for contaminated and aggressive liquid media is developed.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 4","pages":"1307 - 1310"},"PeriodicalIF":0.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultrasonic Liquid Extraction Using Advanced Cavitation in the Process of Disposal of Spent Lithium-Ion Batteries","authors":"O. M. Gradov,&nbsp;I. V. Zinov’eva,&nbsp;Yu. A. Zakhodyaeva,&nbsp;A. A. Voshkin","doi":"10.1134/S0040579525600329","DOIUrl":"10.1134/S0040579525600329","url":null,"abstract":"<p>The ultrasonic cavitation extraction scheme uses dissolution of waste material in deep eutectic solvent to remove it from the substrate and then extract the valuable element with help of the ultrasonic liquid membrane method. A detailed description of this method is given for the case of using high-power ultrasound under typical conditions of cavitation caused by standing ultrasonic waves when its threshold is significantly exceeded and the extraction process is determined by cavitation parameters and limitations. An expression is obtained for the behavior over time of the amount of the extracted element and the dependence of this parameter on the magnitude of the acoustic pressure. The spatial distribution of the velocity of acoustic flow caused by cavitation is found in the one-dimensional case.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 4","pages":"973 - 979"},"PeriodicalIF":0.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Injection of Superheated Water Vapor into a Porous Reservoir Saturated in the Initial State with Methane and Its Hydrate","authors":"M. K. Khasanov,&nbsp;M. V. Stolpovskii","doi":"10.1134/S0040579524601985","DOIUrl":"10.1134/S0040579524601985","url":null,"abstract":"<p>The work presents a mathematical model of the process of pumping of superheated water vapor into a semi-infinite natural porous reservoir, which in its initial state is saturated with a gas (methane) and its gas hydrate, in a flat-one-dimensional approximation. The most general case is considered, when four zones of different composition of the saturating phases and three moving boundary surfaces separating these zones appear in a natural reservoir: between the first and second zones, on which condensation of superheated water vapor occurs; between the second and third zones, where displacement of condensed methane water takes place; and between the third and fourth zones, where the dissociation of the gas hydrate occurs. In the considered formulation of the problem, the first zone of the porous reservoir is saturated with superheated water vapor, the second zone is saturated with condensed water, the third zone is saturated with methane and still water (released during the dissociation of gas hydrate), and the fourth zone of the reservoir is saturated with methane and its gas hydrate. On the basis of a numerical solution, the hydrodynamic and temperature fields that arise in the porous reservoir are studied. It is shown that solutions with the indicated areas and boundaries exist only at relatively low values of injection pressure and reservoir permeability. It is established that an increase in both the injection pressure and the reservoir permeability leads to a noticeable increase only in the coordinates of the boundary separating the second and third regions; in this case, the coordinate of the methane hydrate decomposition front is practically independent of the indicated parameters. An increase in the values of these parameters leads to the confluence of the boundaries of methane displacement and gas hydrate decomposition. The dependence of the limiting value of the injection pressure on the permeability at which these boundaries merge is obtained.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 4","pages":"1272 - 1278"},"PeriodicalIF":0.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methodical Approach to Studies of Magnetic Interaction of Fine Particles in an Aqueous Suspension Using Computer Simulation","authors":"S. P. Ostapenko,&nbsp;A. S. Opalev","doi":"10.1134/S0040579524602012","DOIUrl":"10.1134/S0040579524602012","url":null,"abstract":"<p>The need to increase the efficiency of mining operations determines the relevance of studying the properties of fine mineral particles for their extraction and reduction of environmental pollution. The development of approaches to studying the magnetic interaction of fine particles is of scientific and practical importance and is associated with complexity of calculating the superposition of their fields when solving the problem of controlling the magnetic properties of the suspension. The work describes a computer model of the dynamics of magnetic particle interaction developed with account for their aggregation under the impact of the magnetic dipole–dipole interaction and the destruction of aggregates during thermal (Brownian) motion in order to predict the magnetic properties of the suspension using the example of magnetite from deposits of the Zaimandrovskii iron ore region. The calculation shows that the electrostatic and dispersion interactions do not have a significant effect on the interaction dynamics of micron and submicron particles of magnetite with account for the experimentally measured zeta potential and the Hamaker’s constant. A procedure is developed for calibrating the computer model of the interaction dynamics of magnetic particles using the temperature dependence of the coefficient of translational diffusion of magnetite particles and the concentration dependence of the magnetic susceptibility of the suspension. An array of calculated values of the diffusion coefficient of the model particles and the initial magnetic susceptibility of their system is formed in a wide range of computer model parameters. A procedure is developed for linking the calculated and experimental data by varying the normalization parameters of the particle size, viscosity of the medium, and thermal energy in order to minimize the maximum discrepancy between the values. The necessity is established of taking into account the change in magnetic properties with a decrease in the size of magnetite particles during the calibration of the magnetic susceptibility of the model system. The developed methodological approach ensures good convergence of the calculated and experimental data and makes it possible to visualize the aggregation of the model particles as the result of dipole–dipole interactions. The developed computer model of the interaction dynamics of magnetic particles can be used to study the effect of an external magnetic field on the aggregation ability of fine magnetite particles in order to control their extraction in separation processes.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 4","pages":"1293 - 1299"},"PeriodicalIF":0.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computer Simulation of the Flow of Non-Newtonian Two-Phase media in Areas of Complex Geometry","authors":"R. I. Ibyatov,&nbsp;F. G. Akhmadiev,&nbsp;R. A. Galimov,&nbsp;D. M. Galiev","doi":"10.1134/S0040579524602000","DOIUrl":"10.1134/S0040579524602000","url":null,"abstract":"&lt;p&gt;Computer modeling of the flow of two-phase non-Newtonian media in areas of complex geometry, which often applies to the elements of various technological equipment, is considered. The basis of the computer modeling is a mathematical model of the flow of non-Newtonian two-phase media in channels and pipes with various curved walls. To construct a mathematical model of the flow of non-Newtonian two-phase media, the equations of conservation of mass and momentum of the mechanics of heterogeneous media are used with the corresponding closing relations for the force of interphase interaction and the rheological law of the state of the medium. Simplified equations taking into account flow features close to one-dimensional, written in an orthogonal coordinate system associated with the flow area, are solved numerically using a modified method of equal flow surfaces. An algorithm for numerical flow calculations is constructed for computer simulation of the process. In the numerical calculations, the location and number of surfaces of equal flow rates varies in a wide range, taking into account the characteristics of the flow, and reasonable input (initial) values of the longitudinal velocity on the streamlines are specified. Numerical calculations are carried out for areas of parabolic and conical shapes, taking into account the inlet section of the flow and the influence of the centrifugal force field. A computational experiment is performed for various values of the channel parameters, the rheological law of the state of the medium, and the flow regimes of the two-phase medium. As a result, it is found that in the initial section the flow is transformed from an initial flat profile to a parabolic one. The flow velocities slow down near the channel walls and accelerate in the center of the flow region. Because of this, in the initial section of the flow region, the streamlines are bent. Knowledge of the velocity field of the carrier phase makes it possible to determine the trajectories of motion of the dispersed phase, which is a determining factor for many technological processes. The constructed mathematical model that describes the hydrodynamic situation in the flow region allows us to conduct a computational experiment to calculate the flow of two-phase non-Newtonian media in curved channels and pipes of complex geometry using the modified method of equal flow surfaces. In this case, specific shapes of the flow region are specified by specifying the corresponding Lame coefficients for the flow region. Based on computer modeling, various flow regimes and the influence of various geometric characteristics of the channel, mass forces, and parameters of the rheological law of the state of the medium on the hydrodynamic flow conditions are studied. At different values of the nonlinearity parameters in the power law of state, the centrifugal force, with its increase, has a stronger influence on the hydrodynamic situation in the channel. The results of ","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 4","pages":"1265 - 1271"},"PeriodicalIF":0.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Conditions of Microreactor Mixing of Reagent Solutions on the Formation and Photocatalytic Properties of BiVO4","authors":"D. P. Elovikov,&nbsp;I. V. Makusheva,&nbsp;S. M. Tikhanova,&nbsp;M. V. Tomkovich,&nbsp;O. V. Proskurina,&nbsp;R. Sh. Abiev,&nbsp;V. V. Gusarov","doi":"10.1134/S0040579525600238","DOIUrl":"10.1134/S0040579525600238","url":null,"abstract":"<p>Microreactor synthesis of bismuth vanadate is carried out with variations in the solution flow rates and reagent concentrations in the solutions. With an increase in the concentration of reagents from 0.01 to 0.03 mol/L (at solution flow rates of 1.5 L/min), an increase in the crystallite size is observed from ~37 to ~76 nm. With an increase in flow rates from 1.5 to 3.2 L/min, the crystallite size and the proportions of monoclinic and tetragonal phases of bismuth vanadate for concentrations of 0.01 and 0.02 mol/L differ insignificantly (within the error limits). This means that a flow rate of 1.5 L/min is sufficient to ensure the required micro-mixing quality. An increase in the flow rate of the reagents during microreactor mixing leads to an increase in the rate of photocatalytic decomposition of the dye. For the same flow rate, the best photocatalytic characteristics are demonstrated by samples obtained with a lower concentration of the initial reagents, which provides a larger proportion of the monoclinic phase of BiVO₄ and a smaller crystallite size of this phase. The possibility of controlled microreactor synthesis of bismuth vanadate with a given phase composition, morphology, and crystallite sizes is shown.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 4","pages":"1112 - 1122"},"PeriodicalIF":0.7,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}