Article
Nanoscience & Nanotechnology
Zhongwen Dong, Chuanyu Yang, Dongpu Zhao, Yanan Wang, Weifeng Chu, Zhaochi Feng, Xiangxue Zhu, Wenjie Xin, Yongchen Shang, Shenglin Liu, Longya Xu
Summary: A new interzeolite transformation method has been developed for the quick synthesis of nanoaggregate catalyst CDM-5, where the formation process of ordered aluminosilicate aggregate species was revealed through UV-Raman spectra and HRTEM, SEM images.
ACS APPLIED NANO MATERIALS
(2021)
Article
Chemistry, Physical
Margarita Popova, Manuela Oykova, Momtchil Dimitrov, Daniela Karashanova, Daniela Kovacheva, Genoveva Atanasova, Agnes Szegedi
Summary: Mono- and bimetallic Ni- and Ru-modified micro-mesoporous ZSM-5 catalysts were prepared and their physicochemical properties were studied. The results showed that the zeolite structure and modification procedure influenced the formation, dispersion, and reducibility of metal oxides. Nickel dispersion was higher and more reducible in the presence of ruthenium in bimetallic catalysts. In CO2 hydrogenation to methane, 10Ni5RuZSM-5 material exhibited the highest activity and selectivity.
Article
Engineering, Chemical
Yuyan Gan, Qian Lv, Yanru Li, Hua Yang, Kaiyang Xu, Lizhi Wu, Yu Tang, Li Tan
Summary: This study investigates the relationship between acid site control and the methane dehydroaromatization (MDA) reaction performance, and tunes the acid sites of the ZSM-5 zeolite by introducing promoters. The results show that appropriate strong Brønsted acid sites are favorable for aromatic formation, while excessive acid sites lead to coke deposition. The stability and aromatic selectivity of the MDA catalyst are further improved by passivating partial Brønsted acid sites using a Silicalite-1 coating.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Environmental
T. A. Palankoev, K. Dement'ev, D. Kuznetsova, R. S. Borisov, A. L. Maximov, S. N. Khadzhiev
Summary: In this research, isotope labeling experiments were used to study the reaction pathways of acetone conversion in hydrocarbon medium in the presence of Y and ZSM-5 zeolites. The results showed that the deuterium labels introduced with acetone were mainly distributed in specific olefins and pentanes, supporting the previously proposed assumption.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Anton A. Gabrienko, Sergei S. Arzumanov, Zoya N. Lashchinskaya, Alexander V. Toktarev, Igor P. Prosvirin, Alexander G. Stepanov
Summary: In this study, the mechanism of n-butane transformation on InO+ modified H-ZSM-5 zeolite was investigated using 13C MAS NMR and FTIR spectroscopy. It was found that n-butane conversion occurred through two parallel pathways: dehydrogenation to n-butene followed by aromatization, and direct oxidation to carboxylate surface species. The activation of n-butane was confirmed to occur through C-H bond dissociation on the In=O bond of the InO+ site. The formed oligomers were converted to aromatics on Bronsted acid sites.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Analytical
Wei Wang, Qinyi Zhang, Ruonan Lv, Dong Wu, Shunping Zhang
Summary: This study successfully enhanced the selectivity to formaldehyde by modifying the surface of metal oxide semiconductors with a zeolite layer, and controlled the thickness of the layer to achieve outstanding performance.
Article
Chemistry, Physical
Alexander A. Kolganov, Anton A. Gabrienko, Alexander G. Stepanov
Summary: Three types of methoxy-like intermediates were generated on Cu-loaded ZSM-5 zeolite, with different forms of copper (Cu2+ cations or [Cu3(mu-O)3]2+ oxo-clusters). The methoxy species on CuO/H-ZSM-5 easily reacted with benzene to form toluene, while those on Cu2+/H-ZSM-5 were less effective for benzene methylation. The methoxy species on Cu2+/H-ZSM-5 could interact with CO to form surface acetate species, whereas CO adsorption by [Cu3(mu-O)3]2+ oxo-clusters on CuO/H-ZSM-5 inhibited the reaction.
CHEMICAL PHYSICS LETTERS
(2023)
Article
Engineering, Chemical
Huahua Fan, Xiaowa Nie, Chunshan Song, Xinwen Guo
Summary: Using density functional theory calculations, this study investigates the reaction networks and key steps in propane aromatization over Zn/ZSM-5 catalyst. The results show that Zn-Lewis acid sites play a crucial role in propane dehydrogenation, while propene aromatization proceeds under the combined action of Bronsted and Zn-Lewis acid sites. Moreover, introducing a second metal component can promote the removal of carbon deposits, leading to enhanced catalyst stability and more active sites for aromatization.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Biochemistry & Molecular Biology
Izabela Kurzydym, Alberto Garbujo, Pierdomenico Biasi, Izabela Czekaj
Summary: Transition-metal-modified zeolites have attracted great interest among scientists recently. Ab initio calculations based on density functional theory were conducted using the Perdew-Burke-Ernzerhof (PBE) functional for exchange and correlation. Cluster models of ZSM-5 zeolites with adsorbed Fe particles on aluminum were used. The adsorption of three iron adsorbates (Fe, FeO, and FeOH) within the pores of the zeolite was investigated with different aluminum arrangements. The analysis of DOS diagram and molecular orbitals revealed the insulating or conducting nature of the systems, which significantly affects their catalytic activity.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Chemistry, Multidisciplinary
Bingyu Liu, Yongchao Wang, Ying Xie, Linfei Xiao, Wei Wang, Wei Wu
Summary: CO2 conversion to aromatics with high selectivity is of great significance but faces challenges due to the chemical inertness of CO2 and high energy barriers. A tandem catalyst combining In2O3-ZnZrOx and hierarchical nanosized ZSM-5 modified by alkali desilication was developed for efficient CO2 conversion. The catalyst demonstrated enhanced adsorption and activation ability of CO2, improved diffusion properties, and achieved high aromatics selectivity with reduced CO selectivity.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Agricultural Engineering
Xinyu Yang, Zezhi Chen, Lu Chen, Huiqiang Yu, Huijuan Gong
Summary: Upgrading landfill gas (LFG) to bio-methane is a feasible solution to utilize its energy and address environmental pollution caused by its emissions. This study developed Cu/H-ZSM-5 zeolites with different copper content and demonstrated their excellent catalytic activity in removing oxygen from simulated LFG. The findings provide valuable insights for the development of cost-effective and high-performance LFG deoxygenation catalysts.
BIOMASS & BIOENERGY
(2023)
Article
Energy & Fuels
Yong Hyun Lim, Hae Won Ryu, Wonho Jung, Kihun Nam, Yeseul Hwang, Do Heui Kim
Summary: The energy efficiency of conventional shale gas processing is hindered by multiple gas fractionation steps, which often require cryogenic conditions. Direct non-oxidative shale gas aromatization eliminates the need for such gas separation processes by converting the majority of the higher hydrocarbons, excluding methane, to yield aromatics. Investigations on the reaction temperature and metal loading found that 700 degrees C reaction over 6 wt% Mo led to maximized benzene, toluene, and xylene (BTX) generation. Though methane conversion over Mo/ZSM-5 was greatly negative, the presence of methane as a reactant was beneficial for BTX production.
Article
Chemistry, Physical
Yanfeng Shen, Zhengxing Qin, Shunsuke Asahina, Natsuko Asano, Guanqun Zhang, Shuya Qian, Yanhang Ma, Zifeng Yan, Xinmei Liu, Svetlana Mintova
Summary: This study reveals the defect-zoning and Al-zoning in pseudo-single ZSM-5 crystals through unbiased NH4F etching, describing the formation process of these zones and establishing the correlation between Al zoning and the spatial distribution of C and Na. The distinct inner heterogeneity in the ZSM-5 crystals sheds light on the crystal growth process, providing insights for developing novel framework structures with targeted properties.
JOURNAL OF MATERIALS CHEMISTRY A
(2021)
Article
Chemistry, Applied
Zoya N. Lashchinskaya, Anton A. Gabrienko, Alexander G. Stepanov
Summary: The transformation of propene on copper-modified ZSM-5 zeolite has been investigated using 13C MAS NMR and FTIR spectroscopy. Two major reaction pathways, namely aromatization to benzene and toluene, and oxidation to acrolein, have been identified. Copper-allyl species are found to be key intermediates in both processes. The role of different active sites, including Cu2+-O2- Lewis acid-base pairs and [Cu3(mu-O)3]2+ oxo-clusters, in the formation of allylic species and the oxidation of copper-allyls has been established. The obtained results are important for the development of zeolite-based catalysts for propene aromatization to simple aromatic compounds and the partial oxidation to acrolein.
MICROPOROUS AND MESOPOROUS MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
A. Rashidvand, M. Kheirmand, B. Roozbehani, S. H. Hosseini
Summary: The purpose of this study was to modify the structure of ZSM-5 zeolite in order to enhance its performance in the cracking process for converting petroleum waste into higher-value products. The findings revealed that modifying the structure of ZSM-5 zeolite with silver led to an increase in propylene yield and improved reaction rates.
ARABIAN JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Physical
Anton A. Gabrienko, Zoya N. Lashchinskaya, Sergei S. Arzumanov, Alexander Toktarev, Dieter Freude, Juergen Haase, Alexander G. Stepanov
Summary: Different Zn species and zeolite topology have varying effects on alkane aromatization reactions, with Zn2+ species showing greater efficiency. The presence of more Bronsted acid sites in ZnO/H-BEA promotes the hydrogenolysis pathway.
Article
Chemistry, Multidisciplinary
Alexander E. Khudozhitkov, Masaki Donoshita, Alexander G. Stepanov, Frederik Philippi, Daniel Rauber, Rolf Hempelmann, Hiroshi Kitagawa, Daniil Kolokolov, Ralf Ludwig
Summary: The complex phase behavior of the glass forming protic ionic liquid has been reported using solid-state NMR spectroscopy, revealing evidence of tunneling driven mobility of hydrogen bonded moieties at high temperatures.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Physical
Alexander E. Khudozhitkov, Peter Stange, Alexander G. Stepanov, Daniil Kolokolov, Ralf Ludwig
Summary: We demonstrate that solid-state NMR spectroscopy is an effective tool for studying the structure, hydrogen bond dynamics, and phase transition behavior of protic ionic liquids (PILs). By analyzing the deuteron line shape and spin relaxation time, we obtain information about the structural and dynamical heterogeneity of the model PIL triethyl ammonium bis(trifluoromethanesulfonyl)amide [TEA][NTf2] in the solid state. The presence of different quadrupole coupling constants for the ND bond of the TEA cation indicates varying hydrogen bond strengths to the nitrogen and oxygen atoms of the NTf2 anion. We also provide insights into the transition processes and energetics of the solid and liquid states of the PIL.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Alexander E. E. Khudozhitkov, Sergei S. S. Arzumanov, Daniil I. I. Kolokolov, Alexander G. G. Stepanov
Summary: UiO-66 (Zr) is a metal-organic framework (MOF) with thermal and chemical stability that is widely used for adsorption-based applications. In this study, H-2 solid-state NMR was used to characterize the dynamics of UiO-66 in hydroxylated and dehydroxylated forms. The results showed that the dehydroxylated form had higher pi-flipping rate and phenylene ring plane librations. The diffusivity of butane isomers was also higher in the dehydroxylated form, which can be explained by the larger effective diameter of the window between cages in this form.
SOLID STATE NUCLEAR MAGNETIC RESONANCE
(2022)
Article
Chemistry, Physical
Ekaterina Sadovskaya, Larisa Pinaeva, Valerii Skazka, Igor Prosvirin
Summary: The performance of MeOx/CeO2 (Me = Fe, Co, Ni) samples in O-18(2) temperature-programmed isotope exchange and N2O decomposition (deN(2)O) was examined. The rate of deN(2)O decreased in the presence of oxygen, suggesting the competitive adsorption of N2O and O-2 on the same sites. Dissociative oxygen adsorption with the subsequent formation of surface oxygen species was observed during isotope oxygen exchange. The same species were likely formed from N2O adsorption and subsequent N-2 evolution to the gas phase.
Article
Chemistry, Physical
S. I. Moseenkov, V. L. Kuznetsov, N. A. Zolotarev, B. A. Kolesov, I. P. Prosvirin, A. V. Ishchenko, A. V. Zavorin
Summary: A comparative study was conducted to investigate the effect of heat treatment on the structure and content of amorphous carbon in deposited AC film, nanodiamonds, carbon black and multiwalled carbon nanotube samples. The use of the 7-peak model for fitting the Raman spectra proved effective in isolating the contribution of amorphous carbon and improving the accuracy of fitting. This model showed validity and efficacy in investigating amorphous carbon in various carbon systems and for comparative studies.
Article
Chemistry, Physical
Lyudmila Okhlopkova, Igor Prosvirin, Mikhail Kerzhentsev, Zinfer Ismagilov
Summary: This study developed thin-film nanosized bimetallic catalysts for use in microreactors, addressing environmental problems in fine organic synthesis. The zinc-doped coating exhibited the highest selectivity and stability in the microcapillary reactor.
Article
Chemistry, Physical
Vladimir V. Chesnokov, Igor P. Prosvirin, Evgeny Yu Gerasimov, Aleksandra S. Chichkan
Summary: A new method for synthesizing boron-doped carbon nanomaterial (B-carbon nanomaterial) is developed, involving the synthesis of graphene via the template method and the deposition of an additional boron-doped graphene layer. The properties of B-carbon nanomaterial, such as thickness and specific surface area, were studied using various techniques. The boron concentration in B-carbon nanomaterial was determined to be approximately 4 wt.%.
Article
Chemistry, Physical
Daria V. V. Yurpalova, Tatyana N. N. Afonasenko, Igor P. P. Prosvirin, Andrey V. V. Bukhtiyarov, Maxim A. A. Panafidin, Zakhar S. S. Vinokurov, Mikhail V. V. Trenikhin, Evgeny Yu. Gerasimov, Tatyana I. I. Gulyaeva, Larisa M. M. Kovtunova, Dmitry A. A. Shlyapin
Summary: Novel bimetallic Pd-Co catalysts supported on Sibunit carbon material were synthesized and used for selective acetylene hydrogenation to produce ethylene. Increasing the Pd:Co molar ratio from 1:0 to 1:2 in 0.5%Pd-Co/C catalysts, treated at 500 degrees C under hydrogen, led to an increase in ethylene selectivity from 60 to 67% (T = 45 degrees C). The catalysts were characterized using various methods and it was found that the optimal catalytic properties were observed in catalysts with a Pd:Co molar ratio of 1:2-1:4.
Article
Computer Science, Information Systems
Ivan D. Yushkov, Liping Yin, Gennadiy N. Kamaev, Igor P. Prosvirin, Pavel V. Geydt, Michel Vergnat, Vladimir A. Volodin
Summary: Nonstoichiometric GeSixOy glass films and many-layer structures were obtained by high-vacuum electron beam vapor deposition. The deposited samples were studied using various techniques and the resistive switching behavior was observed in the fabricated memristor metal-insulator-semiconductor (MIS) structures. Intermediate resistance states were observed in many-layer structures, which could have potential applications in multi-bit memristors and neural network simulations.
Article
Chemistry, Inorganic & Nuclear
Ksenia A. Nadeina, Sergey V. Budukva, Yuliya V. Vatutina, Polina P. Mukhacheva, Evgeniy Yu. Gerasimov, Vera P. Pakharukova, Igor P. Prosvirin, Tatyana V. Larina, Oleg V. Klimov, Aleksandr S. Noskov, Victor V. Atuchin
Summary: Among the known synthesis procedures and reagents for unsupported Ni-Mo-W catalysts, there is no consensus about optimal preparation conditions. In this study, Ni-Mo-W precursors were prepared via three different techniques and characterized. The catalytic activity was found to be significantly higher when all active metals are available in a mixed phase. The catalyst prepared by the spray drying method showed the highest activity.
Article
Biochemistry & Molecular Biology
Nikolai S. Nesterov, Vera P. Pakharukova, Alexey A. Philippov, Igor P. Prosvirin, Anton S. Shalygin, Oleg N. Martyanov
Summary: The influence of reaction medium on the surface structure and properties of a Ni-based catalyst used in the reductive transformations of aromatic substrates has been studied. It was found that the conversion of certain substrates caused changes in the catalyst surface structure, while others did not. Additionally, after indole conversion, the catalyst surface remained enriched with nitrogen-containing compounds.
Article
Chemistry, Physical
Jing Niu, Yu-Ting Miao, Wei David Wang, Meng-Tong Ruan, Zhi-Peng Wang, Hua-Dong Xue, Si-Min Yu, Chong Liu, Jian-Feng Wu, Wei Wang
Summary: The crucial role of surface ethoxy species, i.e., equilibrium with ethene in the primary step and further alkylation to form the C-C bond, was confirmed for the first time through a selective C-13-labeling protocol and a multitechnique approach during the adsorption of ethene on zeolite H-Y.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Zixuan Chen, Scott R. Docherty, Pierre Florian, Agnieszka Kierzkowska, Ilia B. Moroz, Paula M. Abdala, Christophe Coperet, Christoph R. Mueller, Alexey Fedorov
Summary: Catalysts with well-defined isolated Ni(ii) surface sites have been prepared on three different silica-based supports. The Ni catalysts with a higher density of strong Bronsted acid sites (BAS) show higher initial activity and productivity in the ethene-to-propene conversion. Propene productivity is closely related to the concentration of C-8 aromatics, suggesting the formation of propene via a carbon-pool mechanism. Furthermore, the deactivation of catalysts with Ni(ii) sites on AlOx can be reversed by calcination, while catalysts with Ni silicate or aluminosilicate sites irreversibly deactivate by forming Ni nanoparticles.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Physical
Alexander A. Kolganov, Anton A. Gabrienko, Ivan Yu Chernyshov, Alexander G. Stepanov, Evgeny A. Pidko
Summary: We conducted a detailed computational study on the reactivity of Zn-modified BEA zeolite towards C-H bond activation of methane. The results highlight the importance of representing the active site as a whole reactive ensemble that includes extra-framework Zn-EF(2+) cations, framework oxygens (O-F(2-)), and zeolite pores. Our findings suggest that the acid properties of the localized extra-framework cations can only provide a rough assessment of the reactivity of cations in metal-containing zeolites. However, there is a correlation between the activation energy and pyrrole adsorption energy.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
