Kinetics and Catalysis最新文献

{"title":"Carbon Foam as a Support for Palladium Catalysts for Selective Hydrogenation of 2-Butyne-1,4-diol","authors":"O. B. Belskaya,&nbsp;M. V. Trenikhin,&nbsp;V. A. Likholobov","doi":"10.1134/S0023158425600750","DOIUrl":"10.1134/S0023158425600750","url":null,"abstract":"<p>The feasibility of using a new carbon material—open-cell carbon foam synthesized from hydrocarbon gas pyrolysis products—as a catalyst support was demonstrated. Modifying the cellular carbon foam by depositing pyrolytic carbon layers on its surface reduced surface defects and increased the material’s strength while maintaining its open-cell structure. Dispersed palladium particles uniformly distributed over the carbon support surface were obtained using the method of depositing palladium polyhydroxo complexes. The prepared catalyst was found to be promising for the selective hydrogenation of 2-butyne-1,4-diol to 2-butene-1,4-diol.</p>","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"66 6","pages":"708 - 716"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Eco-Friendly Fischer Esterification Using Cation-Exchanged Montmorillonite as a Natural Heterogeneous Catalyst","authors":"Khawla Bouafina,&nbsp;Fatiha Belferdi,&nbsp;Farida Bouremmad,&nbsp;Ines Makhlouf,&nbsp;Houda Yennoune","doi":"10.1134/S0023158424602754","DOIUrl":"10.1134/S0023158424602754","url":null,"abstract":"<p>This study presents a simple, effective, inexpensive, and environmentally friendly method for synthesizing methyl salicylate via Fischer esterification using cation-exchanged montmorillonite (Mt) as a natural heterogeneous catalyst. Montmorillonite was modified with different cations to produce Mt–Co²⁺, Mt–Fe³⁺, Mt–Cr³⁺, and Mt–Fe²⁺. Characterization by X-ray powder diffraction (XRD) and scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM–EDX) revealed that the cation-exchange process preserved the clay’s fundamental structure. The modified montmorillonite achieved higher conversions faster at milder temperatures, suggesting industrial catalytic potential. Methyl salicylate yields varied with the cation: Fe³⁺ (78%) and Cr³⁺ (77%) provided the highest yields, likely due to their stronger Lewis acidity, which enhances carbonyl group activation during esterification. These findings indicate that cation-exchanged montmorillonite holds promise as an industrial catalyst.</p>","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"66 6","pages":"633 - 638"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"White Poplar Leaf-Derived Solid Acid Catalysts for Efficient Catalytic Synthesis of Dihydropyrimidinones","authors":"Jixia Wang,&nbsp;Guangwu Zhang,&nbsp;Huize Zhang,&nbsp;Peilan Chen,&nbsp;Wenyan Li,&nbsp;Qiang Hu,&nbsp;Yaqiong Wang,&nbsp;Xinyu Bai,&nbsp;Miao He,&nbsp;Quanlu Yang,&nbsp;Shang Wu","doi":"10.1134/S0023158425600154","DOIUrl":"10.1134/S0023158425600154","url":null,"abstract":"<p>A carbon-based solid acid catalyst was successful prepared from white poplar leaves and <i>p</i>-toluenesulfonic acid in one-step proces. It could be used as catalyst for the coupling reaction of di-carbonyl compounds with urea and fatty aldehydes at 101°C in 4 h. The products of 3,4-dihydropyridine-2(1<i>H</i>)-ones (DHPMs) were isolated in good yields due to the high density of sulfonic acid groups (0.53 mmol/g). More importantly, the catalyst LP can be recycled at least eight times without significant decrease of catalytic activity. Facile operation, short reaction time, high activity and yields make the protocol to be a robust path to obtain dihydropyrimidinones.</p>","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"66 6","pages":"700 - 707"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tailoring the Secondary Porous Structure and Acidic Properties of Micro-mesoporous SAPO-11 by the Silica Source for Efficient Hydroisomerization of n-hexadecane","authors":"D. O. Bagdanova,&nbsp;D. V. Serebrennikov,&nbsp;N. A. Filippova,&nbsp;D. Sh. Sabirov,&nbsp;A. I. Malunov,&nbsp;O. S. Travkina,&nbsp;R. Z. Kuvatova,&nbsp;M. R. Agliullin","doi":"10.1134/S0023158425601044","DOIUrl":"10.1134/S0023158425601044","url":null,"abstract":"<p>The efficiency of hydroisomerization catalysts for higher <i>n</i>-paraffins based on SAPO-11 molecular sieve is significantly affected by diffusion limitations in the micropores, which reduces their activity, selectivity, and operational stability. To address this issue, this study investigates the influence of silicon sources with different dispersity (3, 20, 200 nm) on the physicochemical and catalytic properties of SAPO-11 synthesized using aluminum isopropoxide. The research employs a suite of characterization techniques, including X-ray fluorescence analysis, X-ray diffraction, ²⁹Si magic-angle spinning nuclear magnetic resonance spectroscopy, scanning electron microscopy, nitrogen adsorption–desorption, ammonia temperature-programmed desorption, and infrared spectroscopy of adsorbed pyridine. It is demonstrated that a decrease in the size of the applied SiO₂ particles leads to an increase in the total concentration of acid sites, changes in morphology, a reduction in crystal size, and an alteration of the secondary porous structure properties. The SAPO-11 samples synthesized using a SiO₂ sol with an average particle size of 3 nm are characterized by the most developed hierarchical porous structure (<i>S</i>_BET = 269 m²/g, <i>S</i>_EX = 68 m²/g, <i>V</i>_meso = 0.14 cm³/g). The bifunctional catalysts based on the synthesized SAPO-11 materials were tested in the hydroisomerization of <i>n</i>-hexadecane. The silicoaluminophosphates synthesized using the SiO₂ sol with an average particle size of 3 nm provided the highest <i>n</i>-hexadecane conversion and C₁₆ isomer selectivity among the studied samples. This performance enabled a total yield of C₁₆ isomers exceeding 80%, which is attributed to a higher concentration and enhanced accessibility of strong acid sites. Thus, controlling the silicon source during the SAPO-11 synthesis is an effective strategy for the rational design of high-performance hydroisomerization catalysts for higher <i>n</i>-paraffins.</p>","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"66 6","pages":"778 - 789"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Promoting the Ignition of Methane–Air Mixtures by Hydrogen Atoms Adsorbed on Coal Dust","authors":"V. V. Azatyan,&nbsp;V. M. Prokopenko,&nbsp;S. K. Abramov","doi":"10.1134/S0023158425601196","DOIUrl":"10.1134/S0023158425601196","url":null,"abstract":"<p>It was established that atomic hydrogen absorbed on coal dust, when in contact with a methane–air mixture, expanded the range of methane flame propagation, which was manifested by a decrease in the lower concentration limit. Coal dust with adsorbed atomic hydrogen intensified combustion and flame propagation. Under the conditions of the present experiment, methane ignited first. The observed patterns confirmed the basic tenets of the theory of heterogeneous development of reaction chains.</p>","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"66 6","pages":"599 - 605"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural Features of Aluminates Ln(Ca)AlO3 (Ln = La, Ce, Pr) and Their Catalytic Properties in Methane Oxidation","authors":"P. R. Vasyutin,&nbsp;M. Yu. Sinev,&nbsp;E. Yu. Lyubimov,&nbsp;Yu. A. Gordienko,&nbsp;M. A. Panafidin,&nbsp;A. V. Bukhtiyarov,&nbsp;I. P. Prosvirin","doi":"10.1134/S0023158425601172","DOIUrl":"10.1134/S0023158425601172","url":null,"abstract":"<p>The structural features and some properties of aluminates of the composition LnAlO₃ (Ln = La, Ce, Pr) are studied. All three aluminates obtained at the final calcination temperature of 900°C have a cubic perovskite structure. In Ce-containing systems, along with it, a highly dispersed CeO₂ phase with a cubic fluorite structure is observed. The cubic perovskite structure is retained upon modification of La and Pr aluminates by substituting 10 at % of Ln³⁺ ions with Ca²⁺ ions; in this case, the unit cell parameter decreases due to the smaller radius of the Ca²⁺ ion compared to Ln³⁺, which indicates isomorphic substitution of Ln³⁺ → Ca²⁺. The catalytic properties of the obtained systems in high-temperature oxidation of methane were studied. The analysis of the relationship between the surface properties studied by X-ray photoelectron spectroscopy and the catalytic properties of La and Pr aluminates allows us to conclude that point defects (presumably O^– oxygen radical ions) participate in the production of C₂ hydrocarbons, a process called oxidative coupling of methane (OCM). In the case of praseodymium aluminate, this mechanism is supplemented by a redox cycle occurring due to the oxidation-reduction of praseodymium ions (Pr³⁺ ⇌ Pr⁴⁺) on the surface of the samples. As a result, samples of similar composition (not modified and equally modified with calcium) based on praseodymium aluminate are significantly more effective as catalysts for the OCM process. Ce-containing samples are unstable under methane oxidation conditions; they decompose with the release of the CeO₂ phase and have very low selectivity for C₂ hydrocarbons. The conditions for a correct comparison of the efficiency of oxide catalysts for the OCM process are determined.</p>","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"66 6","pages":"682 - 699"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nature of Nickel(II) Compounds Formed upon Interaction of an Amine–Imine Ni(II) Complex with MAO and AlMe3 According to In Situ NMR Data","authors":"I. E. Soshnikov,&nbsp;E. P. Talsi","doi":"10.1134/S0023158425600701","DOIUrl":"10.1134/S0023158425600701","url":null,"abstract":"<p>The mechanism of catalytic action of α-diimine nickel complexes, one of the most widely used post-metallocene catalysts for ethylene polymerization, remains the subject of extensive discussion. It is generally recognized that so-called “cationic” Ni(II) complexes play a key role in the catalytic cycle, serving as the sites where chain initiation, branching, and chain growth occur. However, most of these highly unstable complexes have been detected in model systems, whereas very limited information is available on nickel(II) complexes present in real catalytic systems. In this work, the nature of intermediates formed during the activation of nickel(II) complexes bearing neutral N,N'-donor amine–imine ligands, related to classical α-diimine complexes, by commonly used cocatalysts was studied using in situ NMR spectroscopy. It was established that unstable “cationic” Ni(II) complexes are also formed in these systems and act as direct precursors of the active catalytic sites.</p>","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"66 6","pages":"744 - 752"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and Numerical Investigation of Ignition of Ammonia–Hydrocarbon Mixtures in Shock Tube Conditions","authors":"A. V. Drakon,&nbsp;A. V. Eremin","doi":"10.1134/S002315842560052X","DOIUrl":"10.1134/S002315842560052X","url":null,"abstract":"<p>The article is devoted to the experimental measurement of ignition delay times of ammonia with additives of CH₄, C₂H₂, C₂H₄, and C₂H₆ behind shock waves and their comparison with the results of numerical simulation using modern kinetic models. A significant discrepancy between the predictions of kinetic mechanisms and the experimental data is demonstrated. The analysis of the sensitivity of the ignition delay time to the rate constants of individual reactions indicates the key role of insufficiently studied reactions of interaction of HO₂ and NH₂ radicals, as well as reactions involving N₂H_<i>x</i> compounds, in the ignition of ammonia at elevated temperatures.</p>","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"66 6","pages":"606 - 617"},"PeriodicalIF":1.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Role of Rh and Mg Oxides in the Etching of Industrial Pt–Pd–Rh–Ru Gauze in the Course of Catalytic Oxidation of Ammonia with Air at 1133 K","authors":"A. N. Salanov,&nbsp;A. N. Serkova,&nbsp;A. S. Zhirnova,&nbsp;L. A. Isupova,&nbsp;V. N. Parmon","doi":"10.1134/S0023158425600865","DOIUrl":"10.1134/S0023158425600865","url":null,"abstract":"<p>Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) at microscope probe electron energies (<i>E</i>₀) of 5 and 20 keV in a range of magnification factors from ×50 to ×100 k were used to characterize the morphology, microstructure and chemical compositions of surface and subsurface regions of etching structures in the industrial Pt−Pd−Rh−Ru gauze with concentrations of 81, 15, 3.5, and 0.5 wt %, respectively, which was used in the oxidation of NH₃ with air at a pressure of 3.6 bar and a temperature of 1133 K. After NH₃ oxidation on the Pt−Pd−Rh−Ru gauze, we observed the microgranular etching structure with grains about 10 µm in size, oxide particles with a diameter of ~80 nm on grain boundaries, and crystal facets 25−50 nm in height on the grain surfaces in the region of weak etching. The oxide particles consisted of 25−50 nm cores with the MgRh₂O₄ spinel composition and 25−50 nm thick SiO₂ shells. These particles were formed during the diffusion of Rh atoms along grain boundaries from the alloy bulk to the surface, the formation of Rh₂O₃ particles, and their reactions with MgO_<i>х</i> and SiO_<i>х</i> impurities from the gas flow of reagents. These processes led to the formation of etch pits, increased the intensity of NH₃ oxidation and temperature, and accelerated the evaporation of volatile oxides PtO₂(gas), RhO₂(gas), etc., into the gas phase, which resulted in the catalyst etching. In the region of strong etching, the etching layer of porous crystal cauliflower agglomerates with different shapes and a size of ~10 µm was observed. The agglomerates had a close phase composition and a low concentration of defects up to a depth of ~500 nm. During the NH₃ oxidation on Pt–Pd–Rh–Ru gauzes, etching structures were formed upon evaporation of volatile oxides PtO₂(gas), RhO₂(gas), etc., on hot regions of the surface and their subsequent condensation on cold fragments of the catalyst.</p>","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"66 5","pages":"563 - 583"},"PeriodicalIF":1.4,"publicationDate":"2025-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145730170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Kinetics of the Oxidation of Tetrahydrofuran in Aqueous Solution Initiated by 2,2'-Azobis(2-amidinopropane) Dihydrochloride","authors":"L. R. Yakupova,&nbsp;A. R. Migranov,&nbsp;R. L. Safiullin","doi":"10.1134/S0023158425600233","DOIUrl":"10.1134/S0023158425600233","url":null,"abstract":"<p>The kinetics of tetrahydrofuran oxidation in aqueous solution initiated by 2,2'-azobis(2-amidinopropane) dihydrochloride were studied. The reaction rate was monitored by oxygen uptake using the manometric method. The initiation rate constant of water-soluble 2,2'-azobis(2-amidinopropane) dihydrochloride was determined within the range 303–323 K: log <i>k</i>_i = (11.9 ± 0.6) – (104.8 ± 4.3)/θ [s^–1], θ = 2.303<i>RT</i> kJ/mol. The rate of tetrahydrofuran oxidation (w) was found to depend linearly on its concentration. A quadratic dependence of w on the initiator concentration was observed. The values of <i>k</i>₂(2<i>k</i>₆)^–0.5 (oxidation parameter) for tetrahydrofuran oxidation were obtained. In Arrhenius coordinates, this parameter is expressed as log (<i>k</i>₂(2<i>k</i>₆)^–0.5) = (2.8 ± 0.1) – (36.1 ± 0.7)/θ [L^0.5 mol^–0.5 s^–0.5], θ = 2.303<i>RT</i> kJ/mol. The rate constants for the reactions of tetrahydrofuran peroxyl radicals with α-tocopherol and with 2,2,5,7,8-pentamethyl-6-chromanol in aqueous medium were determined as (2.0 ± 0.3) × 10⁵ L mol^–1 s^–1 (303–318 K) and (2.8 ± 0.5) × 10⁵ L mol^–1 s^–1 (309 K), respectively.</p>","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"66 5","pages":"489 - 495"},"PeriodicalIF":1.4,"publicationDate":"2025-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145730175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}