A. V. Panfilov, A. V. Korobkov, V. V. Buzmakov, V. V. Tereshin
{"title":"Absorption of Zirconium Tetrachloride by a KCl–AlCl3 Melt as Applied to the Extractive Distillation of Zirconium and Hafnium Tetrachlorides","authors":"A. V. Panfilov, A. V. Korobkov, V. V. Buzmakov, V. V. Tereshin","doi":"10.1134/S0040579525700381","DOIUrl":"10.1134/S0040579525700381","url":null,"abstract":"<div><p>The process of ZrCl<sub>4</sub> vapor absorption by a KCl–AlCl<sub>3</sub>–ZrCl<sub>4</sub> melt is studied on a pilot setup within a temperature range of 324–424°C in columns of different types. The dependence of the equilibrium ZrCl<sub>4</sub> concentration on temperature is established within the studied range of temperatures and pressures. The number of trays required to attain the equilibrium concentration is determined. Some recommendations on the reflux condenser operation regimes in the process of extractive ZrCl<sub>4</sub> and HfCl<sub>4</sub> distillation are given.</p></div>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"59 1","pages":"219 - 224"},"PeriodicalIF":0.6,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145145209","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}
G. G. Vinokurov, N. F. Struchkov, A. K. Kyichkin, M. P. Lebedev
{"title":"Use of Cluster Theory on a Square Lattice to Describe the Formation of Porous Structure on the Surface of Flat Basalt–Polymer Composite Materials During Their Climatic Degradation","authors":"G. G. Vinokurov, N. F. Struchkov, A. K. Kyichkin, M. P. Lebedev","doi":"10.1134/S0040579525700162","DOIUrl":"10.1134/S0040579525700162","url":null,"abstract":"<p>A statistical model for the formation of the porous structure of the outer surface of flat basalt–plastic composite materials during their climatic degradation is proposed. The distribution of the porous structure is considered as a two-dimensional cluster structure on a square lattice, and its quantitative characteristics are used to describe porosity during climatic degradation. In the statistical model, an increase in the probability of filling the square lattice corresponds to the duration of climatic degradation of basalt plastic materials.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"59 1","pages":"83 - 89"},"PeriodicalIF":0.6,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145145491","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}
A. S. Gnedenkov, S. L. Sinebryukhov, V. S. Filonina, A. N. Minaev, S. V. Gnedenkov
{"title":"Multifunctional Coatings with Self-Healing Effect on Magnesium Alloy MA8","authors":"A. S. Gnedenkov, S. L. Sinebryukhov, V. S. Filonina, A. N. Minaev, S. V. Gnedenkov","doi":"10.1134/S0040579525700034","DOIUrl":"10.1134/S0040579525700034","url":null,"abstract":"<div><p>An increase in the corrosion resistance of magnesium and its alloys is achieved by forming hybrid smart coatings. The introduction of a corrosion inhibitor makes it possible to control the degradation rate of the material due to the self-healing effect of the coating. Additional polymer treatment significantly increases the corrosion resistance and wear resistance of the material. The inhibitor efficiency and the mechanism of anti-corrosion protection of the alloy are established.</p></div>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"59 1","pages":"9 - 19"},"PeriodicalIF":0.6,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145145540","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":"Heat Exchange Equipment with Swirling Coolant Flows","authors":"A. E. Sokolov, A. A. Sidyagin, V. M. Kosyrev","doi":"10.1134/S0040579525700356","DOIUrl":"10.1134/S0040579525700356","url":null,"abstract":"<p>The paper explores methods for enhancing heat transfer through swirling flows and presents an overview of relevant designs. It examines key principles underlying the use of swirling flows, assessing their advantages and limitations. Specifically, the study analyzes heat exchangers with rotating flows, identifies their benefits and challenges, and discusses the design solutions employed to achieve optimal technical performance.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"59 1","pages":"203 - 207"},"PeriodicalIF":0.6,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145145072","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}
M. A. Medkov, G. F. Krysenko, D. G. Epov, E. E. Dmitrieva, S. I. Ivannikov, E. I. Shamrai
{"title":"Integrated Processing of Gold-Containing Raw Materials Using a Mixture of Ammonium Bifluoride and Ammonium Sulfate","authors":"M. A. Medkov, G. F. Krysenko, D. G. Epov, E. E. Dmitrieva, S. I. Ivannikov, E. I. Shamrai","doi":"10.1134/S0040579525700307","DOIUrl":"10.1134/S0040579525700307","url":null,"abstract":"<div><p><b>Abstract</b>—The possibility of processing tungsten- and gold-containing mineral raw materials using a mixture of NH<sub>4</sub>HF<sub>2</sub> and (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub> was studied. It was determined that heating of these raw materials with these reagents in the temperature range up to 200°C leads to fluorination of the components of the raw materials to form simple and complex fluorides, and a further increase in temperature is accompanied by the formation of ammonium bisulfate NH<sub>4</sub>HSO<sub>4</sub>, which leads to the conversion of fluorides into double sulfates. The effect of NH<sub>4</sub>HF<sub>2</sub> content in the reaction mixture on the degree of primary processing of the mineral raw materials was demonstrated. Ways of isolating the components of the ore raw materials in the form of commercial products were proposed.</p></div>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"59 1","pages":"168 - 173"},"PeriodicalIF":0.6,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145145074","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}
E. M. Nazaryan, A. G. Arustamyan, A. A. Akopyan, E. S. Agamyan, A. M. Arakelyan
{"title":"Recovery of Copper and Molybdenum from Waste Generated by Copper-Molybdenum Plants","authors":"E. M. Nazaryan, A. G. Arustamyan, A. A. Akopyan, E. S. Agamyan, A. M. Arakelyan","doi":"10.1134/S0040579525700253","DOIUrl":"10.1134/S0040579525700253","url":null,"abstract":"<p>The sequential extraction of molybdenum and copper into solution from copper-molybdenum production tailings by leaching was studied. Molybdenum was extracted from the tailings using sodium hypochlorite, followed by copper extraction from the remaining residue with a diluted sulfuric acid solution. The processes were carried out at low temperatures and atmospheric pressure.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"59 1","pages":"139 - 141"},"PeriodicalIF":0.6,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145145542","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}
S. I. Dvoretskii, D. S. Dvoretskii, E. I. Akulinin, K. I. Meronyuk, V. B. Usachev
{"title":"Modern Approaches to Development of Flexible Pressure Swing Adsorption Units for Separation of Hydrogen-Containing Gaseous Mixtures","authors":"S. I. Dvoretskii, D. S. Dvoretskii, E. I. Akulinin, K. I. Meronyuk, V. B. Usachev","doi":"10.1134/S0040579525601013","DOIUrl":"10.1134/S0040579525601013","url":null,"abstract":"<p>A new approach to the development of a methodology for the integrated design of cyclic adsorption processes and installations for separating multicomponent gas mixtures (in the presence of uncertainty in some of the initial data during design) is presented, forming the prerequisites for effective control and automation. The article describes the composition of a problem-oriented hardware and software complex intended for conducting pre-project scientific research and preparing initial data for design and substantiation of the adoption of design solutions in the hardware and technological design of cyclic adsorption processes and installations (for separating hydrogen-containing gas mixtures and concentrating high-purity hydrogen gas, widely used in various industries and the social sphere). The problem statements for one- and two-stage optimal design of flexible multi-adsorber pressure swing adsorption (PSA) units are formulated, and engineering algorithms are developed that allow optimal design decisions to be made to ensure safe and optimal (in terms of minimum reduced costs, cost price of manufactured products, and other performance indicators) operation of pressure swing adsorption units.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 6","pages":"1957 - 1979"},"PeriodicalIF":0.7,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143676374","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":"Navier–Stokes and Darcy–Brinkmann Models for Synthesis of Micron Particles of Magnesium–Zinc Ferrite","authors":"A. A. Markov","doi":"10.1134/S0040579525600676","DOIUrl":"10.1134/S0040579525600676","url":null,"abstract":"<p>The processes of heat and mass transfer in a direct-flow reactor during the synthesis of micron particles of magnesium–zinc ferrite (MCF) are numerically investigated. A new formulation of the problem of synthesis of MCF by the method of carbon combustion is proposed, taking into account the variability of the permeability and porosity of the mixture of the reactant and product particles. The results of calculations using the Navier–Stokes equations with distributed resistance to gas movement in the pores (NS model) and the Darcy–Brinkman equations (DB model) with the same initial parameters are compared. The differences in the calculations of the indicated models for low and high permeability of a mixture of micron-sized reagent particles are discussed. The modes for which both models give similar results and the modes of significant differences in combustion and synthesis rates, caused by the convective mechanism of heat and momentum transfer in the case of variable porosity, are noted. It is shown that more intense heat transfer in the NS model accelerates the growth of the specific volume of the solid phase due to thermal expansion. The calculation results indicate the importance of non-stationary processes of gas momentum transfer in the pores of a flow reactor and confirm the advantages of the NS model in studying the synthesis of micron particles of complex oxides by the carbon combustion method. The studies were conducted for fast-flowing processes and were limited by the synthesis time interval, which was limited by the initial concentrations of the reagents.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 5","pages":"1594 - 1609"},"PeriodicalIF":0.7,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143676404","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":"Droplet Dynamics in the Rotating Layer of a Separator with a Tangent Swirler","authors":"V. V. Kharkov, O. S. Dmitrieva, A. N. Nikolaev","doi":"10.1134/S0040579525601153","DOIUrl":"10.1134/S0040579525601153","url":null,"abstract":"<p>The intensification of heat and mass transfer is associated with the swirling of the flow using swirlers and the influence of separation layers near it; therefore, the strong dependence of the intensification process on the peculiarities of the movement of droplets in a rotating layer inside the device is obvious. The efficiency of the two-phase flow separation process is determined by the design of the separator used, as well as the fluid dynamics of the interacting flows; therefore, there is a need for a deeper understanding of the physical mechanisms developing in such complex flow fields. The design and principle of operation of a separation device with a tangent swirler are considered. To determine the main parameters of the layer, a computation of the movement of liquid droplets separated from the blades of the swirler is performed. The analysis of the forces acting on the droplet is carried out. The results of a calculation of the trajectories of droplets based on the inlet velocity of the gas and their diameter are presented. The total residence time of the droplet in the contact zone with the swirler blades is very significant and, by an order of magnitude, exceeds the separation time of a drop of sprayed liquid of equal diameter. The dependences determining the time of the droplet flight, the departure of the droplet into the separation zone, the height of the droplet separation, the number of interactions of the droplet with the blades, and the residence time of the droplet in the rotating layer are presented. Numerical calculations have shown that, when the dispersed phase moves in the rotating layer, the number of droplet impacts on the blades of a tangent swirler increases with decreasing droplet diameter and gas flow velocity. The results allow us to quantify the refresh rates of the surface of the interphase contact in the separation device with the tangent swirler.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 5","pages":"1766 - 1770"},"PeriodicalIF":0.7,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143676407","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}
M. V. Maslova, P. E. Evstropova, N. V. Mudruk, Yu. P. Semushina
{"title":"Desorption Kinetics of Heavy-Metal Cations onto Titanium Phosphate","authors":"M. V. Maslova, P. E. Evstropova, N. V. Mudruk, Yu. P. Semushina","doi":"10.1134/S0040579525601086","DOIUrl":"10.1134/S0040579525601086","url":null,"abstract":"<p>The desorption kinetics of divalent ions (Cu<sup>2+</sup>, Mn<sup>2+</sup>, Co<sup>2+</sup>, Ni<sup>2+</sup>) onto amorphous titanium phosphate is studied. It is established that the desorption of heavy-metal cations onto titanium phosphate is realized by a mixed mechanism: external diffusion and internal diffusion. It is shown from the diffusion coefficients calculated that diffusion in the pores of the sorbent occurs without steric hindrance. For all of the ions studied, a pseudo-second-order model adequately describes the chemical interaction. It is shown that the rate and selectivity of desorption is markedly determined by the effective radius of the hydrated ions.</p>","PeriodicalId":798,"journal":{"name":"Theoretical Foundations of Chemical Engineering","volume":"58 6","pages":"2028 - 2033"},"PeriodicalIF":0.7,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143676429","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}