Pub Date : 2024-01-13DOI: 10.1007/s11237-024-09789-6
N. L. Hes, A. M. Mylin, S. V. Prudius
The conversion of dihydroxyacetone solution in methanol to methyl lactate has been studied in flow regime using xSnO2/Al2O3-supported catalysts that have been characterized by XRD, low-temperature nitrogen (ad)desorption analysis, and UV-Vis spectroscopy. It is found that Lewis and Brønsted acid sites of the surface of SnO2-containing catalysts play a crucial role in the selective conversion of dihydroxyacetone to methyl lactate. The formation of methyl lactate with a selectivity of 90% is achieved on 5%SnO2/Al2O3 catalyst at 160°C, 1.0 MPa, and under feed rate of 4 mmol C3H6O3/(gcat·h).
{"title":"Catalytic Conversion of Dihydroxyacetone to Methyl Lactate Over SnO2/Al2O3 Catalysts","authors":"N. L. Hes, A. M. Mylin, S. V. Prudius","doi":"10.1007/s11237-024-09789-6","DOIUrl":"10.1007/s11237-024-09789-6","url":null,"abstract":"<p>The conversion of dihydroxyacetone solution in methanol to methyl lactate has been studied in flow regime using xSnO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub>-supported catalysts that have been characterized by XRD, low-temperature nitrogen (ad)desorption analysis, and UV-Vis spectroscopy. It is found that Lewis and Brønsted acid sites of the surface of SnO<sub>2</sub>-containing catalysts play a crucial role in the selective conversion of dihydroxyacetone to methyl lactate. The formation of methyl lactate with a selectivity of 90% is achieved on 5%SnO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> catalyst at 160°C, 1.0 MPa, and under feed rate of 4 mmol C<sub>3</sub>H<sub>6</sub>O<sub>3</sub>/(g<sub>cat</sub>·h).</p>","PeriodicalId":796,"journal":{"name":"Theoretical and Experimental Chemistry","volume":"59 4","pages":"302 - 306"},"PeriodicalIF":0.7,"publicationDate":"2024-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139459867","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}
Pub Date : 2024-01-13DOI: 10.1007/s11237-024-09788-7
A. I. Trypolskyi, N. I. Ermokhina, V. M. Grebennikov, D. O. Klymchuk, G. R. Kosmambetova, O. Z. Didenko, P. A. Manoryk
By using a fractal approach, it is found that the irregular structure of the surface of titanium dioxide-based catalyst has a significant effect on the values of the rate constants and activation energies of the reaction of dehydrogenation and dehydration of ethanol, n-propanol, and iso-propanol. Kinetics of ethyl and propyl alcohol conversions on titanium dioxide samples with different textures and morphologies is studied. Dependencies of activation energy and pre-exponential factor of the reaction rate on the alcohol conversions on the TiO2 samples on their structural characteristics, particularly a fractal dimension, are established.
{"title":"Influence of the Morphology of the Surface of Titanium Dioxide Nanocrystallites on Their Catalytic Properties in the Alcohol Conversion Reactions","authors":"A. I. Trypolskyi, N. I. Ermokhina, V. M. Grebennikov, D. O. Klymchuk, G. R. Kosmambetova, O. Z. Didenko, P. A. Manoryk","doi":"10.1007/s11237-024-09788-7","DOIUrl":"10.1007/s11237-024-09788-7","url":null,"abstract":"<p>By using a fractal approach, it is found that the irregular structure of the surface of titanium dioxide-based catalyst has a significant effect on the values of the rate constants and activation energies of the reaction of dehydrogenation and dehydration of ethanol, n-propanol, and iso-propanol. Kinetics of ethyl and propyl alcohol conversions on titanium dioxide samples with different textures and morphologies is studied. Dependencies of activation energy and pre-exponential factor of the reaction rate on the alcohol conversions on the TiO<sub>2</sub> samples on their structural characteristics, particularly a fractal dimension, are established.</p>","PeriodicalId":796,"journal":{"name":"Theoretical and Experimental Chemistry","volume":"59 4","pages":"293 - 301"},"PeriodicalIF":0.7,"publicationDate":"2024-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139459860","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}
Pub Date : 2024-01-13DOI: 10.1007/s11237-024-09784-x
N. I. Romanovska, G. V. Korzhak, V. M. Grebennikov, O. V. Shulzshenko, P. S. Yaremov, N. I. Ermokhina, P. A. Manoryk
Codoped C,S-TiO2 nanostructures with similar structural and dimensional characteristics and different surface acidity have been obtained using a hydrothermal sol–gel method in the presence thiourea or sulfuric acid. It is established that C,S-TiO2 obtained in the presence of H2SO4 are characterized with acidity of 0.45 mmol/g that results in a high photocatalytic activity in the process of ethanol oxidation. It is shown that C,S-TiO2 obtained in the presence of thiourea, exhibits photocatalytic activity in the reaction of hydrogen evolution under UV and visible light irradiation, which increases with surface acidity decreasing.
{"title":"Effect of Surface Acidity of Codoped C,S-TiO2 on Their Photocatalytic Properties in the Hydrogen Evolution and Ethanol Oxidation Processes","authors":"N. I. Romanovska, G. V. Korzhak, V. M. Grebennikov, O. V. Shulzshenko, P. S. Yaremov, N. I. Ermokhina, P. A. Manoryk","doi":"10.1007/s11237-024-09784-x","DOIUrl":"10.1007/s11237-024-09784-x","url":null,"abstract":"<p>Codoped C,S-TiO<sub>2</sub> nanostructures with similar structural and dimensional characteristics and different surface acidity have been obtained using a hydrothermal sol–gel method in the presence thiourea or sulfuric acid. It is established that C,S-TiO<sub>2</sub> obtained in the presence of H<sub>2</sub>SO<sub>4</sub> are characterized with acidity of 0.45 mmol/g that results in a high photocatalytic activity in the process of ethanol oxidation. It is shown that C,S-TiO<sub>2</sub> obtained in the presence of thiourea, exhibits photocatalytic activity in the reaction of hydrogen evolution under UV and visible light irradiation, which increases with surface acidity decreasing.</p>","PeriodicalId":796,"journal":{"name":"Theoretical and Experimental Chemistry","volume":"59 4","pages":"260 - 267"},"PeriodicalIF":0.7,"publicationDate":"2024-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139459776","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}
Pub Date : 2024-01-13DOI: 10.1007/s11237-024-09786-9
M. L. Ovcharov, P. I. Glukhova, A. M. Mishura, V. M. Granchak
Strontium and barium titanates with a perovskite structure have been obtained using a sol–gel method. It is shown that these materials are characterized by high values of a band gap (3.1 and 3.2 eV for SrTiO3 and BaTiO3, respectively). Morphological characteristics of the obtained titanates are considered, the presence of micrometer aggregates, consisting of nanosticks (diameter of 20-40 nm, length of 100-200 nm) and nanocrystals with size of 20-70 nm, is established. The photocatalytic properties of the samples in the process of NO2 decomposition to N2 and O2 under UV irradiation (λ = 365 nm) are studied, a possible mechanism of nitrogen dioxide conversion is discussed.
{"title":"Photocatalytic Activity of SrTiO3 and BaTiO3 Nanostructures, Formed by the Sol-Gel Method, in the Process of Nitrogen Dioxide Decomposition","authors":"M. L. Ovcharov, P. I. Glukhova, A. M. Mishura, V. M. Granchak","doi":"10.1007/s11237-024-09786-9","DOIUrl":"10.1007/s11237-024-09786-9","url":null,"abstract":"<p>Strontium and barium titanates with a perovskite structure have been obtained using a sol–gel method. It is shown that these materials are characterized by high values of a band gap (3.1 and 3.2 eV for SrTiO<sub>3</sub> and BaTiO<sub>3</sub>, respectively). Morphological characteristics of the obtained titanates are considered, the presence of micrometer aggregates, consisting of nanosticks (diameter of 20-40 nm, length of 100-200 nm) and nanocrystals with size of 20-70 nm, is established. The photocatalytic properties of the samples in the process of NO<sub>2</sub> decomposition to N<sub>2</sub> and O<sub>2</sub> under UV irradiation (λ = 365 nm) are studied, a possible mechanism of nitrogen dioxide conversion is discussed.</p>","PeriodicalId":796,"journal":{"name":"Theoretical and Experimental Chemistry","volume":"59 4","pages":"276 - 284"},"PeriodicalIF":0.7,"publicationDate":"2024-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139459777","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}
Pub Date : 2024-01-12DOI: 10.1007/s11237-024-09787-8
O. V. Shevchenko, K. V. Burenkova, S. A. Kurta
Complexation of a copolymer of styrene and 5-methyl-5-hexene-2,4-dione with cobalt chloride in dimethylformamide occurs with the formation of metallopolymers of two types, namely with intra- and extramolecular binding of β-diketone groups, the ratio of which depends on the concentration of the initial macromolecular ligand. It has been established that the polymer metal complexes differ in the geometry of the coordination unit, molecular weights, and metal content resulting in the different reactivity to initiation of graft radical polymerization of methyl methacrylate.
{"title":"Cobalt(II) Metallopolymers with 5-methyl-5-hexene-2,4-dione Immobilized on a Polystyrene Matrix as Initiators of Radical Polymerization of Metyl Methacrylate","authors":"O. V. Shevchenko, K. V. Burenkova, S. A. Kurta","doi":"10.1007/s11237-024-09787-8","DOIUrl":"10.1007/s11237-024-09787-8","url":null,"abstract":"<p>Complexation of a copolymer of styrene and 5-methyl-5-hexene-2,4-dione with cobalt chloride in dimethylformamide occurs with the formation of metallopolymers of two types, namely with intra- and extramolecular binding of β-diketone groups, the ratio of which depends on the concentration of the initial macromolecular ligand. It has been established that the polymer metal complexes differ in the geometry of the coordination unit, molecular weights, and metal content resulting in the different reactivity to initiation of graft radical polymerization of methyl methacrylate.</p>","PeriodicalId":796,"journal":{"name":"Theoretical and Experimental Chemistry","volume":"59 4","pages":"285 - 292"},"PeriodicalIF":0.7,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139459726","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}
Pub Date : 2023-11-10DOI: 10.1007/s11237-023-09775-4
V. Sh. Saberov, G. F. Rayenko, A. S. Avksentiev, L. M. Vakhitova, N. I. Korotkikh
New catalytic methods for the hydrodehalogenation of haloarenes with hydrogen and hydrogen-containing reagents (metal and non-metal hydrids, organic hydrogen-containing compounds, etc.), which are essential for fine organic synthesis and neutralization of toxic production waste and persistent organic pollutants. The paper focuses on such catalysts as complexes of stable heterocyclic carbenes, transition metals, and nanosized metal particles and their composites, as the most promising for industrial chemistry. Catalysts with particularly high efficiency have been highlighted.
{"title":"Catalytic Hydrodehalogenation of Haloarenes with Hydrogen and Hydrogen-Containing Compounds: A Review","authors":"V. Sh. Saberov, G. F. Rayenko, A. S. Avksentiev, L. M. Vakhitova, N. I. Korotkikh","doi":"10.1007/s11237-023-09775-4","DOIUrl":"10.1007/s11237-023-09775-4","url":null,"abstract":"<div><div><p>New catalytic methods for the hydrodehalogenation of haloarenes with hydrogen and hydrogen-containing reagents (metal and non-metal hydrids, organic hydrogen-containing compounds, etc.), which are essential for fine organic synthesis and neutralization of toxic production waste and persistent organic pollutants. The paper focuses on such catalysts as complexes of stable heterocyclic carbenes, transition metals, and nanosized metal particles and their composites, as the most promising for industrial chemistry. Catalysts with particularly high efficiency have been highlighted.</p></div></div>","PeriodicalId":796,"journal":{"name":"Theoretical and Experimental Chemistry","volume":"59 3","pages":"151 - 177"},"PeriodicalIF":1.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134796050","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}
Pub Date : 2023-11-03DOI: 10.1007/s11237-023-09777-2
C. Sezgin, İ. Erden
It is shown that the derivatives of 4,5-diazafluorenone-9-hydrazone containing thiophene and aldehyde anchor groups, as well as mixed-ligand Ru(II) complexes with these dyes and bipyridine, have the properties of sensibilizers of TiO2-based photovoltaic cells. The power conversion efficiency (η) in such photovoltaic elements under simulated 100 mW/cm2 solar radiation is in the range of 0.25-0.48%. The value of η in the case of compounds, bearing thiophene-2,5-dicarbaldehyde fragment as an anchor, is almost two times higher compared to the analogues, containing non-substituted thiophene fragment.
{"title":"Photovoltaic Properties of Thiophene-Containing Derivatives of 4,5-Diazafluorene and Their Ruthenium(II) Complexes","authors":"C. Sezgin, İ. Erden","doi":"10.1007/s11237-023-09777-2","DOIUrl":"10.1007/s11237-023-09777-2","url":null,"abstract":"<div><div><p>It is shown that the derivatives of 4,5-diazafluorenone-9-hydrazone containing thiophene and aldehyde anchor groups, as well as mixed-ligand Ru(II) complexes with these dyes and bipyridine, have the properties of sensibilizers of TiO<sub>2</sub>-based photovoltaic cells. The power conversion efficiency (η) in such photovoltaic elements under simulated 100 mW/cm<sup>2</sup> solar radiation is in the range of 0.25-0.48%. The value of η in the case of compounds, bearing thiophene-2,5-dicarbaldehyde fragment as an anchor, is almost two times higher compared to the analogues, containing non-substituted thiophene fragment.</p></div></div>","PeriodicalId":796,"journal":{"name":"Theoretical and Experimental Chemistry","volume":"59 3","pages":"186 - 192"},"PeriodicalIF":1.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134878251","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}
Pub Date : 2023-10-31DOI: 10.1007/s11237-023-09780-7
M. M. Shorokhov, V. M. Olabin, M. Klevs, G. Zageris, V. Geža, V. S. Kharitonov
The influence of carbon dioxide concentration in biogas on the composition of its reforming products has been studied to achieve optimal methanol synthesis conditions. A model of the biogas reforming stage is proposed. An optimal concentration of carbon dioxide in biogas essential for maximizing methanol production has been found. The effect of geometric characteristics of the mixing device on the homogeneity of the reacting flow, which is a critical for the process performance, has been established.
{"title":"Effect of Co2 Content on Biogas-to-Syngas Conversion for Methanol Production","authors":"M. M. Shorokhov, V. M. Olabin, M. Klevs, G. Zageris, V. Geža, V. S. Kharitonov","doi":"10.1007/s11237-023-09780-7","DOIUrl":"10.1007/s11237-023-09780-7","url":null,"abstract":"<div><div><p>The influence of carbon dioxide concentration in biogas on the composition of its reforming products has been studied to achieve optimal methanol synthesis conditions. A model of the biogas reforming stage is proposed. An optimal concentration of carbon dioxide in biogas essential for maximizing methanol production has been found. The effect of geometric characteristics of the mixing device on the homogeneity of the reacting flow, which is a critical for the process performance, has been established.</p></div></div>","PeriodicalId":796,"journal":{"name":"Theoretical and Experimental Chemistry","volume":"59 3","pages":"207 - 213"},"PeriodicalIF":1.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134797912","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}
Pub Date : 2023-10-31DOI: 10.1007/s11237-023-09781-6
O. M. Gonchar, S. D. Nesin, Yu. V. Saveliev
A method of montmorillonite modification with polar oligourethane containing reactive amino groups has been developed. It is shown that functionalized montmorillonite is capable of adding aromatic and aliphatic diisocyanates, as well as sequential addition of aromatic diisocyanates and glycerol, which is essential for montmorillonite application as filler for polymer materials. According to wide-angle X-ray scattering, interlayer distance d001 of montmorillonite in the obtained samples varies depending on nature of oligomer macromolecules in the interlayer space that is explained with different conformation and orientation of aromatic and aliphatic oligourethane fragments.
{"title":"Functionalization of the Surface of Montmorillonite with Cationic Oligourethane Capable of Diisocyanate Addition","authors":"O. M. Gonchar, S. D. Nesin, Yu. V. Saveliev","doi":"10.1007/s11237-023-09781-6","DOIUrl":"10.1007/s11237-023-09781-6","url":null,"abstract":"<div><div><p>A method of montmorillonite modification with polar oligourethane containing reactive amino groups has been developed. It is shown that functionalized montmorillonite is capable of adding aromatic and aliphatic diisocyanates, as well as sequential addition of aromatic diisocyanates and glycerol, which is essential for montmorillonite application as filler for polymer materials. According to wide-angle X-ray scattering, interlayer distance d<sub>001</sub> of montmorillonite in the obtained samples varies depending on nature of oligomer macromolecules in the interlayer space that is explained with different conformation and orientation of aromatic and aliphatic oligourethane fragments.</p></div></div>","PeriodicalId":796,"journal":{"name":"Theoretical and Experimental Chemistry","volume":"59 3","pages":"214 - 221"},"PeriodicalIF":1.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134797913","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}
Pub Date : 2023-10-31DOI: 10.1007/s11237-023-09782-5
D. A. Krysenko, V. Ya. Demchenko
The effect of the zeolite framework composition on the selectivity and thermodynamic parameters of ion exchange is studied for the exchange reaction of Ca2+ cations on Na-forms of clinoptilolites from nine deposits of Central and Southeast Europe, Northeast Asia, and North America. An increase in the thermodynamic affinity of Na-forms towards Ca2+ cations is shown with a decrease in the Si/Al ratio in their zeolite framework.
{"title":"Effect of the Composition of the Zeolite Framework of Natural Clinoptilolites on the Exchange of Cations Na+ On Ca2+","authors":"D. A. Krysenko, V. Ya. Demchenko","doi":"10.1007/s11237-023-09782-5","DOIUrl":"10.1007/s11237-023-09782-5","url":null,"abstract":"<div><div><p>The effect of the zeolite framework composition on the selectivity and thermodynamic parameters of ion exchange is studied for the exchange reaction of Ca<sup>2+</sup> cations on Na-forms of clinoptilolites from nine deposits of Central and Southeast Europe, Northeast Asia, and North America. An increase in the thermodynamic affinity of Na-forms towards Ca<sup>2+</sup> cations is shown with a decrease in the Si/Al ratio in their zeolite framework.</p></div></div>","PeriodicalId":796,"journal":{"name":"Theoretical and Experimental Chemistry","volume":"59 3","pages":"222 - 230"},"PeriodicalIF":1.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134797914","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号