Kinetics and Catalysis最新文献_第10页

Chapter VIII. The Determining Role of Chain Combustion in Flame Propagation 第 VIII 章.链式燃烧在火焰传播中的决定性作用

IF 1.3 4区化学

Kinetics and Catalysis Pub Date : 2024-08-20 DOI: 10.1134/S0023158424601323

V. V. Azatyan

{"title":"Chapter VIII. The Determining Role of Chain Combustion in Flame Propagation","authors":"V. V. Azatyan","doi":"10.1134/S0023158424601323","DOIUrl":"10.1134/S0023158424601323","url":null,"abstract":"Until recently, it was attempted to explain the flame propagation without considering the chain nature of combustion, but the contradictions between theory and experiments failed to be explained. The difference in the roles of reaction chains and self-heating was not considered, as well as the role of heterogeneous chain termination. These issues are addressed in this chapter. Greater uncertainty in the quantitative interpretation of gas combustion is due to the limited information on heterogeneous reactions of active particles and the nonstationary state of the surface. Under these limitations, the propagation of flame of the 4H2 + O2 mixture was simulated. To reduce the role of the nonstationary state of the surface, conditions for the limiting role of diffusion of H atoms to the walls were chosen. A method for solving differential equations and conditions for replacing the Laplace operator with an averaging rate constant for the chemisorption of atomic hydrogen are described. The flat flame approximation is used. The flame characteristics for their comparison with the results of experiments conducted with the participation of the author were obtained. Experimental results showing the strong dependence of all characteristics of flame propagation on the changing properties of the surface are presented.","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"65 1 supplement","pages":"S80 - S89"},"PeriodicalIF":1.3,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199896","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}

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Chapter I. Some Information from Chemical Kinetics 第 I 章来自化学动力学的一些信息

IF 1.3 4区化学

Kinetics and Catalysis Pub Date : 2024-08-20 DOI: 10.1134/S0023158424601232

V. V. Azatyan

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Efficient Conversion of NO2 to NO over Mo2C/AC by Controlling Carbonization Time 通过控制碳化时间在 Mo2C/AC 上将 NO2 高效转化为 NO

IF 1.3 4区化学

Kinetics and Catalysis Pub Date : 2024-08-15 DOI: 10.1134/S0023158423601067

Shifang Mu, Yan Wang, Hongliang Wang, Yujing Weng, Qi Sun, Yulong Zhang

{"title":"Efficient Conversion of NO2 to NO over Mo2C/AC by Controlling Carbonization Time","authors":"Shifang Mu, Yan Wang, Hongliang Wang, Yujing Weng, Qi Sun, Yulong Zhang","doi":"10.1134/S0023158423601067","DOIUrl":"10.1134/S0023158423601067","url":null,"abstract":"Mo2C/AC-x converters were prepared using nitric acid pretreated activated carbon (AC) as a carrier, with x representing the carbonization time. The performance of the converter in converting NO2 to NO was evaluated in a fixed bed reactor. The Mo2C/AC-x converters were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 physisorption and desorption, H2 programmed temperature reduction (H2-TPR) and NO2 temperature-programmed desorption–mass spectrometry (NO2 TPD-MS). The NO2 to NO conversion rate decreases in the following order: Mo2C/AC-4 > Mo2C/AC-2 > Mo2C/AC-6 > Mo2C/AC-0.5. Short carbonization times, like 0.5 h, led to incomplete carbonization of MoO2 to β-Mo2C. Conversely, long carbonization times, like 6 h, resulted in the formation of carbon deposits that can block pores or cover active sites, leading to decreased catalytic performance. Mo2C/AC-4 has the highest specific surface area and pore volume. The NO2 conversion rate of Mo2C/AC-4 reached 98.9% at 150°C, demonstrating direct efficient conversion of NO2 to NO at a lower temperature.","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"65 3","pages":"271 - 279"},"PeriodicalIF":1.3,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199901","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}

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Catalytic Properties of Immobilized Imidazolium Phosphomolybdates in the Peroxide Oxidation of Sulfur- and Nitrogen-Containing Compounds: Influence of the Structure of the Cation 固定化咪唑磷钼酸盐在含硫和含氮化合物过氧化物氧化过程中的催化特性：阳离子结构的影响

IF 1.3 4区化学

Kinetics and Catalysis Pub Date : 2024-08-15 DOI: 10.1134/S0023158424601414

V. S. Gorbunov, V. M. Zelikman, I. A. Ivanin, V. G. Krasovsky, K. V. Oskolok, A. G. Popov, I. G. Tarkhanova

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Assessment of Physical and Chemical Effects of Ethanol Enrichment on the Autoignition of Biodiesel Surrogates 评估乙醇富集对生物柴油替代物自燃的物理和化学影响

IF 1.3 4区化学

Kinetics and Catalysis Pub Date : 2024-08-15 DOI: 10.1134/S0023158423600888

Y. Rezgui, M. Guemini, A. Tighezza

{"title":"Assessment of Physical and Chemical Effects of Ethanol Enrichment on the Autoignition of Biodiesel Surrogates","authors":"Y. Rezgui, M. Guemini, A. Tighezza","doi":"10.1134/S0023158423600888","DOIUrl":"10.1134/S0023158423600888","url":null,"abstract":"This study employed detailed chemistry in conjunction with a zero-dimentional model (senkin code) to numerically investigate the ignition delay times of ternary biodiesel surrogate fuels (comprising n-heptane/methyl-decanoate/methyl-9-decenoate in an 80/10/10% molar ratio) blended with ethanol at ratios of 5, 10, 15 and 20%. Equivalence ratios covered the lean (Φ = 0.5), stoichiometric (Φ = 1.0) and rich (Φ = 1.5) mixtures with temperatures ranging from 700 to 1000 K and pressures from 20 to 40 bar. The primary objective of this work was to assess and quantify the role of chemical and physical (dilution and thermal) effects resulting from ethanol enrichment on the ignition delay times of these blended fuels. The modeling results indicated that ethanol addition had a distinctly different effect on the biodiesel reactivity in the low- and intermediate-temperature regimes. Below 900 K, ethanol addition decreased reactivity, whereas the opposite trend was observed in the temperature range of 900–1000 K. Irrespective of the ethanol ratio, a significant reduction in ignition delay times occurred upon increasing chamber pressure and equivalence ratio, with this phenomenon being more pronounced at higher chamber temperatures. Finally, it was found that under all modeling conditions, the physical effect of ethanol enrichment was less pronounced than the chemical one.","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"65 3","pages":"219 - 228"},"PeriodicalIF":1.3,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199893","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}

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On the Michaelis–Menten Kinetics and its Modified Models: Solutions and Some Exact Identities 论 Michaelis-Menten 动力学及其修正模型：溶液和一些精确特性

IF 1.3 4区化学

Kinetics and Catalysis Pub Date : 2024-08-15 DOI: 10.1134/S0023158423601298

Alejandro Pérez Paz

{"title":"On the Michaelis–Menten Kinetics and its Modified Models: Solutions and Some Exact Identities","authors":"Alejandro Pérez Paz","doi":"10.1134/S0023158423601298","DOIUrl":"10.1134/S0023158423601298","url":null,"abstract":"Using the properties of the Lambert function we review the analytical solutions of the Michaelis–Menten (MM) kinetics and other related models. We derive several quantities of interest such as the half-life and the area under the curve (AUC). The effect of varying the parameters in the Beal–Schnell–Mendoza solution and its asymptotic time behavior were analyzed. The Maclaurin expansion of the time evolution of substrate concentration up to sixth order is presented. These expressions were tested on the well-known problem of ethanol elimination from the human body and excellent agreement was found. In addition, a closed-form solution for the derived problem that combines simultaneously MM and zeroth-order kinetics is derived. This problem was solved by a suitable transformation of variables that casts the original differential equation into a functionally equivalent MM problem with termination time. To finish, analytical solutions for the MM process in parallel with zeroth- and first-order kinetics are presented here as well. We checked all equations against the numerically exact solution of the corresponding differential equation and perfect agreement was found in all cases.","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"65 3","pages":"229 - 241"},"PeriodicalIF":1.3,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199894","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}

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Acid Modification Method for Preparation of Attapulgite/Cordierite Coating Honeycomb and its Environmental Applications 制备凹凸棒石/堇青石涂层蜂窝的酸性改性方法及其环境应用

IF 1.3 4区化学

Kinetics and Catalysis Pub Date : 2024-08-15 DOI: 10.1134/S0023158423600931

Wei Liu, Fengqin Wu, Jingwei Liu, Jie Meng, Bingying Gao, Shixiang Zuo, Chao Yao

{"title":"Acid Modification Method for Preparation of Attapulgite/Cordierite Coating Honeycomb and its Environmental Applications","authors":"Wei Liu, Fengqin Wu, Jingwei Liu, Jie Meng, Bingying Gao, Shixiang Zuo, Chao Yao","doi":"10.1134/S0023158423600931","DOIUrl":"10.1134/S0023158423600931","url":null,"abstract":"The specific surface area of attapulgite was significantly enhanced (from 128 to 212 m2/g) by its purification with sodium hexametaphosphate and nitric acid. Subsequently, an acid modification method was employed to prepare a coated attapulgite cordierite honeycomb with a specific surface area approximately 39 times larger than that of the bare cordierite honeycomb. SEM images showed that the surface of the cordierite was rough and uneven, with the attapulgite filling the large pores on its surface, forming a “nail-like” interaction between the coating and the carrier. After loading the catalyst, no significant mass loss was observed after 1 h of ultrasonic testing, indicating good adhesion stability of the coating. Furthermore, under test conditions of GHSV (Gas Hourly Space Velocity) = 10 000 h–1 and a toluene concentration of 1500 ppm, the prepared integrated catalyst exhibited excellent activity for the catalytic oxidation of toluene, with T50 and T90 values of 261 and 290°C, respectively, suggesting broad application prospects.","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"65 3","pages":"298 - 307"},"PeriodicalIF":1.3,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199902","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}

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Kinetics of Hydrogen and Toluene Production from Methylcyclohexane in the Presence of a PtSn/Al2O3 Catalyst 在 PtSn/Al2O3 催化剂作用下从甲基环己烷制取氢气和甲苯的动力学研究

IF 1.3 4区化学

Kinetics and Catalysis Pub Date : 2024-08-15 DOI: 10.1134/S0023158424601426

A. D. Lozhkin, L. D. Iskhakova, F. O. Milovich, E. A. Katsman, L. G. Bruk

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Effect of K and Ni Promoters on Mo2C/Al2O3 Catalyst for Higher Alcohols Synthesis from Syngas K 和 Ni 促进剂对以合成气为原料合成高级醇的 Mo2C/Al2O3 催化剂的影响

IF 1.3 4区化学

Kinetics and Catalysis Pub Date : 2024-08-15 DOI: 10.1134/S0023158424601189

Zhi Yang, Mingsheng Luo, Qinglong Liu, Chenmeng Li, Yatao Wang, Hongjuan Li, Lifei Yao

{"title":"Effect of K and Ni Promoters on Mo2C/Al2O3 Catalyst for Higher Alcohols Synthesis from Syngas","authors":"Zhi Yang, Mingsheng Luo, Qinglong Liu, Chenmeng Li, Yatao Wang, Hongjuan Li, Lifei Yao","doi":"10.1134/S0023158424601189","DOIUrl":"10.1134/S0023158424601189","url":null,"abstract":"The direct production of higher alcohols from syngas in a single step remains a great challenge. In this work, a series of K and Ni promoted Mo2C/Al2O3 catalysts were prepared by impregnation method to enhance the selectivity of Mo2C-based catalysts for the one-step conversion of syngas to higher alcohols. The catalysts were continuously tested under the following conditions: 300°C, 3.0 MPa, velocity—11.50 ({text{Lg}}_{{{text{Mo}}}}^{{ - 1}}) h–1, H2/CO ratio of 2. The catalysts promoted with K and Ni demonstrated the highest total alcohol selectivity of 67.7%. Moreover, the selectivity for total C2+ alcohols reached as high as 56%, with 37% being ethanol. X-ray diffraction (XRD), hydrogen temperature-programmed reduction (H2-TPR) and X-ray photoelectron spectroscopy (XPS) characterization data reveal that K can promote the crystallinity of β-Mo2C, lower the catalyst reduction temperature and increase the proportion of high-valent Mo on the catalyst surface. In addition, adding Ni as a promoter to the KMo2C/Al2O3 catalyst can generate a synergistic effect to further enhance the catalytic activity and the selectivity of higher alcohols.","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"65 3","pages":"251 - 260"},"PeriodicalIF":1.3,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199904","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}

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Low-Temperature and High-Efficiency Catalytic Conversion N2O to N2 in the Presence of CO over Nonnoble Metal Cu–Fe Catalyst 在非贵金属 Cu-Fe 催化剂上低温高效催化将一氧化氮转化为 N2

IF 1.3 4区化学

Kinetics and Catalysis Pub Date : 2024-08-15 DOI: 10.1134/S0023158423600955

Jianqiang Zhang, Yanyan Li, Lifang Cai, Yakun Li, Xuzhao Yang, Yingying Zhang, Jingli Han, Shide Wu

{"title":"Low-Temperature and High-Efficiency Catalytic Conversion N2O to N2 in the Presence of CO over Nonnoble Metal Cu–Fe Catalyst","authors":"Jianqiang Zhang, Yanyan Li, Lifang Cai, Yakun Li, Xuzhao Yang, Yingying Zhang, Jingli Han, Shide Wu","doi":"10.1134/S0023158423600955","DOIUrl":"10.1134/S0023158423600955","url":null,"abstract":"Nitrous oxide (N2O) is a long-lived stratospheric ozone-depleting substance with an atmospheric lifetime of 116 years. It is also a greenhouse gas with a global warming potential value of about 310. Due to its high kinetic stability and thermal decomposition temperature exceeding 1000°C, the treatment and recovery of nitrous oxide pose significant engineering and climate challenges. In this study, we introduce a Cu–Fe oxide catalyst that demonstrates efficient and low-temperature conversion of N2O to N2 using readily available reductant CO. The oxide catalyst was synthesized by a solvothermal method and a “from bottom to top” technique. Characterizations by X-ray diffraction (XRD), CO temperature-programmed desorption (C-O‑TPD), scanning electron microscopy (SEM), and BET indicate that the catalyst with weaker CO adsorption sites, fewer strong CO adsorption sites, suitable particle size, good dispersion and high specific surface area performs excellent reaction activity in the reduction of N2O to N2 by CO. The active site of Cu is stronger, and the addition of Fe can promote dispersion of the Cu active site and increase the exposure to the active site. A new approach has been proposed to address nitrous oxide emissions, a greenhouse gas with high thermodynamic stability, in the chemical industrial process that generates nitrous oxide as a byproduct.","PeriodicalId":682,"journal":{"name":"Kinetics and Catalysis","volume":"65 3","pages":"261 - 270"},"PeriodicalIF":1.3,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199900","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}

引用次数: 0