Pub Date : 2022-09-26DOI: 10.33609/2708-129x.88.08.2022.79-96
Mykola Koshel, Sergiy Koshel, S. Korpach
A new method of differential itn-metry has been developed for accurate determination of ion transfer numbers in materials with ion-exchange properties. Such materials include ion exchange membranes, liquid phase ion exchangers and ionic liquids, industrial ion exchange resins. The method is intended as an alternative simplified assessment of the functional properties of ion-exchange resins used in industrial technologies of water purification, water treatment, and extraction at enterprises of various industries. Such accurate information is obtained in special laboratories at enterprises by long-term and expensive physical and chemical methods. Transfer numbers give an indirect assessment of the quality of ion exchangers, but the method of differential itn-metry gives a result in a short 30-minute experiment on the electrolysis of a NaOH or NaCl solution in a three-chamber electrolyzer reactor. The electrolyzer-reactor contains an electrolyte volume of up to 40 cm3. The middle chamber of the electrolyzer-reactor has a variable width from 0.05 to 0.2 cm and an area of 10 cm2 perpendicular to the direction of the electric current. The primary result of each experiment was the functions of the electrolyte concentration dynamics C(τ) in the extreme cathode and anode chambers of the electrolyzer- reactor, where the dynamics of the readings of the flow resistometric sensor developed by us were recorded during the electrolysis process. The effective transfer number itn* was determined by mathematical data processing using a system of approximation functions. The method of differential itn-metry will be effective for other resins with amphoteric properties. The use of such a method could be used in works for the study of a wide range of problems in environmental monitoring and management of environmental projects.
{"title":"METHOD OF EVALUATION OF TRANSFER NUMBERS IN ION-EXCHANGE MATERIALS","authors":"Mykola Koshel, Sergiy Koshel, S. Korpach","doi":"10.33609/2708-129x.88.08.2022.79-96","DOIUrl":"https://doi.org/10.33609/2708-129x.88.08.2022.79-96","url":null,"abstract":"A new method of differential itn-metry has been developed for accurate determination of ion transfer numbers in materials with ion-exchange properties. Such materials include ion exchange membranes, liquid phase ion exchangers and ionic liquids, industrial ion exchange resins. The method is intended as an alternative simplified assessment of the functional properties of ion-exchange resins used in industrial technologies of water purification, water treatment, and extraction at enterprises of various industries. Such accurate information is obtained in special laboratories at enterprises by long-term and expensive physical and chemical methods. Transfer numbers give an indirect assessment of the quality of ion exchangers, but the method of differential itn-metry gives a result in a short 30-minute experiment on the electrolysis of a NaOH or NaCl solution in a three-chamber electrolyzer reactor. The electrolyzer-reactor contains an electrolyte volume of up to 40 cm3. The middle chamber of the electrolyzer-reactor has a variable width from 0.05 to 0.2 cm and an area of 10 cm2 perpendicular to the direction of the electric current. \u0000The primary result of each experiment was the functions of the electrolyte concentration dynamics C(τ) in the extreme cathode and anode chambers of the electrolyzer- reactor, where the dynamics of the readings of the flow resistometric sensor developed by us were recorded during the electrolysis process. The effective transfer number itn* was determined by mathematical data processing using a system of approximation functions. \u0000The method of differential itn-metry will be effective for other resins with amphoteric properties. The use of such a method could be used in works for the study of a wide range of problems in environmental monitoring and management of environmental projects.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80267884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-26DOI: 10.33609/2708-129x.88.07.2022.16-28
T. Plutenko, O. V’yunov, O. Fedorchuk, S. Solopan, M. Plutenko, B. Khomenko
Solid solutions of nickel-zinc ferrites ZnxNi1-xFe2O4 were synthesized by two different methods: synthesis in microemulsions and by stepwise precipitation. The properties of the resulted nano-sized particles synthesized by two different methods were compared. It was found that the increase in zinc content leads to an increase in the lattice parameters. During the synthesis by the method of microemulsions, the temperature of a single-phase product formation is 400 °C, while by the method of precipitation, a single-phase product formation begins at 600 °C. It was shown that the materials synthesized by both methods have similar unit cell parameters. The average size of ferrite nanoparticles synthesized in microemulsions is smaller, lattice strain is higher compared to ferrites synthesized by stepwise precipitation. Also, lower treatment temperatures provide higher stoichiometry, and homogeneity of materials while magnetization difference is negligible. The particles of the obtained powders have high saturation magnetization Ms = 45.6 Am2/kg for synthesis from microemulsions and Ms = 44.8 Am2/kg for co-precipitated samples, the low coercive force Hc = 1.3 kA/m and Hc = 3 kA/m, respectively. Changes made make synthesized particles more applicable in film deposition, and manufacturing of high-quality magnetic coatings.
{"title":"MICROEMULSION-BASED METHOD OF SYNTHESIS OF ZINC-NICKEL FERRITE AND THEIR MAGNETIC PROPERTIES","authors":"T. Plutenko, O. V’yunov, O. Fedorchuk, S. Solopan, M. Plutenko, B. Khomenko","doi":"10.33609/2708-129x.88.07.2022.16-28","DOIUrl":"https://doi.org/10.33609/2708-129x.88.07.2022.16-28","url":null,"abstract":"Solid solutions of nickel-zinc ferrites ZnxNi1-xFe2O4 were synthesized by two different methods: synthesis in microemulsions and by stepwise precipitation. The properties of the resulted nano-sized particles synthesized by two different methods were compared. It was found that the increase in zinc content leads to an increase in the lattice parameters. During the synthesis by the method of microemulsions, the temperature of a single-phase product formation is 400 °C, while by the method of precipitation, a single-phase product formation begins at 600 °C. It was shown that the materials synthesized by both methods have similar unit cell parameters. The average size of ferrite nanoparticles synthesized in microemulsions is smaller, lattice strain is higher compared to ferrites synthesized by stepwise precipitation. Also, lower treatment temperatures provide higher stoichiometry, and homogeneity of materials while magnetization difference is negligible. The particles of the obtained powders have high saturation magnetization Ms = 45.6 Am2/kg for synthesis from microemulsions and Ms = 44.8 Am2/kg for co-precipitated samples, the low coercive force Hc = 1.3 kA/m and Hc = 3 kA/m, respectively. Changes made make synthesized particles more applicable in film deposition, and manufacturing of high-quality magnetic coatings.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90435198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-26DOI: 10.33609/2708-129x.88.07.2022.45-55
V. Demchenko, L. Matkovska, О. Matkovska
Kinetic methods for analyzing the curing process of thermosetting polymer systems are an important area for controlling the formation conditions for viscosity, which depends on the temperature and chemical composition of the composite. The curing reactions determine the morphology and structure of the system, affecting the properties of the final material. This work analyzes the curing process of polymer composites based on epoxy oligomer - polyethylene glycol diglycidyl ether (DEG), polyethylene polyamine hardener (PEPA) and lithium perchlorate salt LiClO4. The initial components, the mixture of DEG/PEPA composition and the DEG/PEPA/LiClO4 system supplemented with salt were investigated. Using the methods of Fourier-transform infrared spectroscopy and rheological analysis in dynamic mode the curing conditions of the systems were established. It was shown that the nature of the distribution of vibration bands in the IR spectra of the DEG/PEPA and DEG/PEPA/LiClO4 systems is a superposition of the IR spectra of the initial components. Lithium perchlorate in the salt-doped initial system is in an undissociated state and dissociates in the polymer matrix over time during the curing of the system. In particular, the time dependences of the concentration of epoxide groups in the DEG/PEPA system calculated using the integral intensity ratios were analyzed by IR spectroscopy data. To study the curing process with increased segmental mobility of the reacting macromolecules, rheokinetic measurements were performed at 50°C. Analysis of the nature of changes in the elastic and viscosity moduli over time allowed us to estimate the gel time of the initial and doped systems. Differences in the IR spectra for both systems before the formation of the three-dimensional structure and at the gel point, as well as the IR spectra of these systems after the curing reaction, were analyzed. Attention was also paid to the nature of the influence of dopant on the curing process and its state in the mixture/composite of DEG/PEPA/LiClO4 composition. Lithium perchlorate LiClO4 is an effective catalyst for the aminolysis of the oxirane ring, which explains the acceleration of the curing reaction of the system in the presence of salt.
{"title":"KINETICS OF HARDENING OF EPOXY-AMINE SYSTEMS DOPED WITH LiClO4","authors":"V. Demchenko, L. Matkovska, О. Matkovska","doi":"10.33609/2708-129x.88.07.2022.45-55","DOIUrl":"https://doi.org/10.33609/2708-129x.88.07.2022.45-55","url":null,"abstract":"Kinetic methods for analyzing the curing process of thermosetting polymer systems are an important area for controlling the formation conditions for viscosity, which depends on the temperature and chemical composition of the composite. The curing reactions determine the morphology and structure of the system, affecting the properties of the final material. This work analyzes the curing process of polymer composites based on epoxy oligomer - polyethylene glycol diglycidyl ether (DEG), polyethylene polyamine hardener (PEPA) and lithium perchlorate salt LiClO4. The initial components, the mixture of DEG/PEPA composition and the DEG/PEPA/LiClO4 system supplemented with salt were investigated. Using the methods of Fourier-transform infrared spectroscopy and rheological analysis in dynamic mode the curing conditions of the systems were established. It was shown that the nature of the distribution of vibration bands in the IR spectra of the DEG/PEPA and DEG/PEPA/LiClO4 systems is a superposition of the IR spectra of the initial components. Lithium perchlorate in the salt-doped initial system is in an undissociated state and dissociates in the polymer matrix over time during the curing of the system. In particular, the time dependences of the concentration of epoxide groups in the DEG/PEPA system calculated using the integral intensity ratios were analyzed by IR spectroscopy data. To study the curing process with increased segmental mobility of the reacting macromolecules, rheokinetic measurements were performed at 50°C. Analysis of the nature of changes in the elastic and viscosity moduli over time allowed us to estimate the gel time of the initial and doped systems. Differences in the IR spectra for both systems before the formation of the three-dimensional structure and at the gel point, as well as the IR spectra of these systems after the curing reaction, were analyzed. Attention was also paid to the nature of the influence of dopant on the curing process and its state in the mixture/composite of DEG/PEPA/LiClO4 composition. Lithium perchlorate LiClO4 is an effective catalyst for the aminolysis of the oxirane ring, which explains the acceleration of the curing reaction of the system in the presence of salt.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88013347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-26DOI: 10.33609/2708-129x.88.07.2022.3-15
L. Sliusarchuk, L. Zheleznova, S. Kuleshov, O. Rohovtsov, O. Trunova, Borys Khomenko
New heterometallic complexes of Сo(II) and Nd(III) with carboxylic acids (succinic, oxalic) and acetylacetone in the presence of phenanthroline or α,α'-dipyridyl have been synthesized. Their thermal properties and the ability to form complex oxides during thermal degradation have been studied. In the process of thermolysis of heterocomplexes, neodymium cobaltate NdCoO3 was obtained, which is confirmed by the results of X-ray powder diffraction. The research has established that the X-ray powder diffraction patterns of the products obtained by thermolysis of heterocomplex [Сo2Nd2(C4Н4O4)5·2Phen]·4Н2О to 1000 °С exhibits peaks at (2θ): 23.40, 33.74, 41.42, 48.32, 54.52, 59.94, 70.58°. This corresponds to the neodymium cobaltate NdCoO3. Neodymium cobaltate crystallizes in the cubic crystal system. The sample was obtained without extraneous phases inclusions. For the samples obtained by the termolysis of heterocomplexes [Сo2Nd2(C2O4)5·2Phen]·4Н2О and NdCo(AA)5·2α,α'-dipy, in addition to the complex oxide NdCoO3, peaks of Nd2O3 were recorded, which crystallizes in the hexagonal crystal system. The X-ray powder diffraction patterns show peaks with 2θ values: 26.92, 29.75, 30.77, 40.54, 47.53, 53.63, 57.08°. The phase ratio of NdCoO3/Nd2O3 after termolysis for the sample of CoNd(AA)5·2α,α'-dipy is ~ 68.9/31.1%; for the sample of [Сo2Nd2(C2O4)5·2Phen]·4Н2О is ~ 50/50%; for the sample of [Сo2Nd2(C4Н4O4)5·2Phen]·4Н2О is NdCoO3 ~ 100%. The average crystallites size of complex oxides was calculated using the Scherer formula. It has been showed that neodymium cobaltate has an average particle size of ~33 nm, regardless of the complex precursor from which it was formed during thermolysis. The catalytic effect of neodymium cobaltates in the hydrogen peroxide decomposition reaction was studied. It was shown that all samples of complex oxides showed a quite high catalytic activity in the all of experiments in the hydrogen peroxide decomposition reactions.
{"title":"SYNTHESIS OF COMPLEX OXIDES OF COBALT-NEODYMIUM FROM HETEROCOMPLEXES AND THEIR CATALYTIC ACTIVITY IN THE DECOMPOSITION OF HYDROGEN PEROXIDE","authors":"L. Sliusarchuk, L. Zheleznova, S. Kuleshov, O. Rohovtsov, O. Trunova, Borys Khomenko","doi":"10.33609/2708-129x.88.07.2022.3-15","DOIUrl":"https://doi.org/10.33609/2708-129x.88.07.2022.3-15","url":null,"abstract":"New heterometallic complexes of Сo(II) and Nd(III) with carboxylic acids (succinic, oxalic) and acetylacetone in the presence of phenanthroline or α,α'-dipyridyl have been synthesized. Their thermal properties and the ability to form complex oxides during thermal degradation have been studied. In the process of thermolysis of heterocomplexes, neodymium cobaltate NdCoO3 was obtained, which is confirmed by the results of X-ray powder diffraction. \u0000The research has established that the X-ray powder diffraction patterns of the products obtained by thermolysis of heterocomplex [Сo2Nd2(C4Н4O4)5·2Phen]·4Н2О to 1000 °С exhibits peaks at (2θ): 23.40, 33.74, 41.42, 48.32, 54.52, 59.94, 70.58°. This corresponds to the neodymium cobaltate NdCoO3. Neodymium cobaltate crystallizes in the cubic crystal system. The sample was obtained without extraneous phases inclusions. For the samples obtained by the termolysis of heterocomplexes [Сo2Nd2(C2O4)5·2Phen]·4Н2О and NdCo(AA)5·2α,α'-dipy, in addition to the complex oxide NdCoO3, peaks of Nd2O3 were recorded, which crystallizes in the hexagonal crystal system. The X-ray powder diffraction patterns show peaks with 2θ values: 26.92, 29.75, 30.77, 40.54, 47.53, 53.63, 57.08°. The phase ratio of NdCoO3/Nd2O3 after termolysis for the sample of CoNd(AA)5·2α,α'-dipy is ~ 68.9/31.1%; for the sample of [Сo2Nd2(C2O4)5·2Phen]·4Н2О is ~ 50/50%; for the sample of [Сo2Nd2(C4Н4O4)5·2Phen]·4Н2О is NdCoO3 ~ 100%. The average crystallites size of complex oxides was calculated using the Scherer formula. It has been showed that neodymium cobaltate has an average particle size of ~33 nm, regardless of the complex precursor from which it was formed during thermolysis. \u0000The catalytic effect of neodymium cobaltates in the hydrogen peroxide decomposition reaction was studied. It was shown that all samples of complex oxides showed a quite high catalytic activity in the all of experiments in the hydrogen peroxide decomposition reactions.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73643448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-26DOI: 10.33609/2708-129x.88.07.2022.29-44
R. Panteleimonov
A literature analysis of sources on synthesis methods and their influence on the structural-morphological, physico-chemical, and electrochemical properties of graphene and graphene-like structures was carried out. It was established that these properties have a clear dependence on the synthesis method, starting materials, and the composition of the synthesis medium. The main ways of changing graphene's structural-morphological, physico-chemical and electrical properties are changes in the synthesis method and conditions that affect the formation of σ-bonds and π-bonds. The presence of these bonds regulates the number of graphene layers and the formation of van der Waals interactions between them, as well as the formation of edge structural defects responsible for electrokinetic and catalytic properties. Changing the gas medium to a liquid one greatly simplifies the synthesis of graphene. Still, in the case of a liquid nitrogen medium, simultaneously with a 2-dimensional structure, it is possible to form 3-dimensional particles up to tens of nanometers in size. Aqueous medium and plasma-arc synthesis methods are the most attractive for obtaining materials with electron-donor conductivity, which have attractive electrochemical and catalytic properties for use in chemical current sources and fuel cells. Using an aqueous environment requires mandatory further heat treatment at temperatures above 250 0C to separate chemisorbed water from the structure, which complicates the synthesis procedure. The advantage of the plasma-arc method for the synthesis of graphene and other carbon nanostructures is its ability to shorten the stages of the synthesis of graphene, the possibility of modifying them directly during the synthesis process by changing the environment, easy management, and obtaining a clean final product. In the modern practice, this method is limited to obtaining coatings on a solid carrier.
{"title":"WAYS OF CHANGING THE STRUCTURAL-MORPHOLOGICAL, PHYSICO-CHEMICAL AND ELECTRICAL PROPERTIES OF GRAPHENES","authors":"R. Panteleimonov","doi":"10.33609/2708-129x.88.07.2022.29-44","DOIUrl":"https://doi.org/10.33609/2708-129x.88.07.2022.29-44","url":null,"abstract":"A literature analysis of sources on synthesis methods and their influence on the structural-morphological, physico-chemical, and electrochemical properties of graphene and graphene-like structures was carried out. It was established that these properties have a clear dependence on the synthesis method, starting materials, and the composition of the synthesis medium. \u0000The main ways of changing graphene's structural-morphological, physico-chemical and electrical properties are changes in the synthesis method and conditions that affect the formation of σ-bonds and π-bonds. The presence of these bonds regulates the number of graphene layers and the formation of van der Waals interactions between them, as well as the formation of edge structural defects responsible for electrokinetic and catalytic properties. Changing the gas medium to a liquid one greatly simplifies the synthesis of graphene. Still, in the case of a liquid nitrogen medium, simultaneously with a 2-dimensional structure, it is possible to form 3-dimensional particles up to tens of nanometers in size. Aqueous medium and plasma-arc synthesis methods are the most attractive for obtaining materials with electron-donor conductivity, which have attractive electrochemical and catalytic properties for use in chemical current sources and fuel cells. Using an aqueous environment requires mandatory further heat treatment at temperatures above 250 0C to separate chemisorbed water from the structure, which complicates the synthesis procedure. The advantage of the plasma-arc method for the synthesis of graphene and other carbon nanostructures is its ability to shorten the stages of the synthesis of graphene, the possibility of modifying them directly during the synthesis process by changing the environment, easy management, and obtaining a clean final product. In the modern practice, this method is limited to obtaining coatings on a solid carrier.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84915440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-27DOI: 10.33609/2708-129x.88.06.2022.102-120
Leon Shteinberg
The catalytic preparation of substituted benzanilides by the reaction of substituted benzoic acids with aniline is an important model process that has been intensively developed recently, in the field of the «green chemistry» concept, direct catalytic amidation, and its study is an urgent scientific and practical task. Within the framework of solving this problem, the catalysis of the acylation of aniline by substituted benzoic acids with trivalent phosphorus compounds P(III) was studied. It was established that P(III) in the amount of only 2% mol. from substituted benzoic acid effectively catalyze this reaction, which proceeds in boiling low-polar solvents with intensive water distillation in an air atmosphere, which leads to obtaining anilides of substituted benzoic acids with a yield close to quantitative. The new catalysts, phosphorus trichloride and tribromide, phosphorous acid, successfully complement the catalytic system tetrabutoxytitanate/polybutoxytitanate, previously used for these purposes, allowing to obtain anilides of aminobenzoic acids with greater selectivity, as well as anilides of oxybenzoic acids. The study of the kinetic regularities of the reaction catalyzed by phosphorus trichloride showed a weak effect of substituents: |ρ| ≤ 0.61. Hammett dependences are represented by curves with a maximum, straight line segments are characteristic only for certain groups of substituents, both for meta- and para-substituted and for orthosubstituted benzoic acids. One of the possible mechanisms of acylation is the formation in situ in the first minutes of the reaction of aniline phosphite, which can act as an oxygen-nucleophilic catalyst, and, upon interaction with substituted benzoic acid, forms the corresponding benzoyl phosphite, which is then attacked by a free aniline molecule to obtain substituted benzanilide. The ortho effect for P(III) catalysis is absent or very weak, in the case of aminobenzoic acids. At the same time, anthranilic acid can form a phosphite with phosphorous acid, which directly participates in catalysis.
{"title":"CATALYSIS OF TRIVALENT PHOSPHORUS COMPOUNDS OF THE REACTIONS OF SUBSTITUTED BENZOIC ACIDS WITH ANILINE","authors":"Leon Shteinberg","doi":"10.33609/2708-129x.88.06.2022.102-120","DOIUrl":"https://doi.org/10.33609/2708-129x.88.06.2022.102-120","url":null,"abstract":"The catalytic preparation of substituted benzanilides by the reaction of substituted benzoic acids with aniline is an important model process that has been intensively developed recently, in the field of the «green chemistry» concept, direct catalytic amidation, and its study is an urgent scientific and practical task. \u0000 Within the framework of solving this problem, the catalysis of the acylation of aniline by substituted benzoic acids with trivalent phosphorus compounds P(III) was studied. It was established that P(III) in the amount of only 2% mol. from substituted benzoic acid effectively catalyze this reaction, which proceeds in boiling low-polar solvents with intensive water distillation in an air atmosphere, which leads to obtaining anilides of substituted benzoic acids with a yield close to quantitative. The new catalysts, phosphorus trichloride and tribromide, phosphorous acid, successfully complement the catalytic system tetrabutoxytitanate/polybutoxytitanate, previously used for these purposes, allowing to obtain anilides of aminobenzoic acids with greater selectivity, as well as anilides of oxybenzoic acids. \u0000The study of the kinetic regularities of the reaction catalyzed by phosphorus trichloride showed a weak effect of substituents: |ρ| ≤ 0.61. Hammett dependences are represented by curves with a maximum, straight line segments are characteristic only for certain groups of substituents, both for meta- and para-substituted and for orthosubstituted benzoic acids. \u0000 One of the possible mechanisms of acylation is the formation in situ in the first minutes of the reaction of aniline phosphite, which can act as an oxygen-nucleophilic catalyst, and, upon interaction with substituted benzoic acid, forms the corresponding benzoyl phosphite, which is then attacked by a free aniline molecule to obtain substituted benzanilide. \u0000 The ortho effect for P(III) catalysis is absent or very weak, in the case of aminobenzoic acids. At the same time, anthranilic acid can form a phosphite with phosphorous acid, which directly participates in catalysis.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86995688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-27DOI: 10.33609/2708-129x.88.06.2022.71-101
V. Pekhnyo, A. Omel’chuk, O. Linyucheva
An overview dedicates to the directions of scientific research and achieved results in the field of electrochemistry, initiated by scientific institutions and in higher educational institutions of Kyiv. Academician O.V. Plotnikov is the forerunner of the world- known Kyiv School of Electrochemistry, formed in the last century's twenties: M.I. Usanovych, V.O. Izbekov, Ya.A. Fialkov, Yu.K. Delimarskyi, I.A. Sheka, and many other scientists known to the general scientific community. O.V. Plotnikov and his followers are one of the first to attempt to combine the most progressive theoretical provisions on electrolytic dissociation, the chemical theory of solutions, and the chemistry of complex compounds for that time. World achievements of the Kyiv School of Electrochemistry were provided by the results of such fundamental research as the chemical theory of solutions, acid-base interactions (Usanovich's theory), the structure of the electric double layer (the Yesin-Markov effect, the reduced Antropov scale of potentials), physical chemistry and electrochemistry of molten electrolytes, kinetics electrode processes, electrometallurgy, electrochemical materials science, electrochemical power engineering. Representatives of our School significantly expanded the knowledge of mass transfer in electrochemical systems with molten electrolytes (the phenomenon of the transfer of metals from the anode to the cathode). New technological processes of obtaining and refining heavy non-ferrous metals (bismuth, lead, indium, etc.), finishing metal surfaces, extraction of radionuclides, electroplating technology, and environmental monitoring have been introduced into the practice of industrial production. Research in electrochemical materials science is closely connected to solving the problems of electrochemical energy, particularly, the creation of new sources of current, including solid-state, hydrogen generators, and converters of solar energy into electrical power. The studies of electrochemical aspects of the extraction of some refractory metals from natural raw materials, the creation of new materials with specified functional properties, catalysts, and electrocatalysts, the latest galvanic coatings, electrode and electrolyte materials for chemical current sources and supercapacitors, valuable inorganic compounds, metal and carbon nanophases, corrosion inhibitors are expanding the scientific direction of electrochemical materials science.
{"title":"SCIENTIFIC ELECTROCHEMICAL SCHOOL OF KYIV","authors":"V. Pekhnyo, A. Omel’chuk, O. Linyucheva","doi":"10.33609/2708-129x.88.06.2022.71-101","DOIUrl":"https://doi.org/10.33609/2708-129x.88.06.2022.71-101","url":null,"abstract":"An overview dedicates to the directions of scientific research and achieved results in the field of electrochemistry, initiated by scientific institutions and in higher educational institutions of Kyiv. Academician O.V. Plotnikov is the forerunner of the world- known Kyiv School of Electrochemistry, formed in the last century's twenties: M.I. Usanovych, V.O. Izbekov, Ya.A. Fialkov, Yu.K. Delimarskyi, I.A. Sheka, and many other scientists known to the general scientific community. O.V. Plotnikov and his followers are one of the first to attempt to combine the most progressive theoretical provisions on electrolytic dissociation, the chemical theory of solutions, and the chemistry of complex compounds for that time. World achievements of the Kyiv School of Electrochemistry were provided by the results of such fundamental research as the chemical theory of solutions, acid-base interactions (Usanovich's theory), the structure of the electric double layer (the Yesin-Markov effect, the reduced Antropov scale of potentials), physical chemistry and electrochemistry of molten electrolytes, kinetics electrode processes, electrometallurgy, electrochemical materials science, electrochemical power engineering. Representatives of our School significantly expanded the knowledge of mass transfer in electrochemical systems with molten electrolytes (the phenomenon of the transfer of metals from the anode to the cathode). New technological processes of obtaining and refining heavy non-ferrous metals (bismuth, lead, indium, etc.), finishing metal surfaces, extraction of radionuclides, electroplating technology, and environmental monitoring have been introduced into the practice of industrial production. Research in electrochemical materials science is closely connected to solving the problems of electrochemical energy, particularly, the creation of new sources of current, including solid-state, hydrogen generators, and converters of solar energy into electrical power. The studies of electrochemical aspects of the extraction of some refractory metals from natural raw materials, the creation of new materials with specified functional properties, catalysts, and electrocatalysts, the latest galvanic coatings, electrode and electrolyte materials for chemical current sources and supercapacitors, valuable inorganic compounds, metal and carbon nanophases, corrosion inhibitors are expanding the scientific direction of electrochemical materials science.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81980483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-27DOI: 10.33609/2708-129x.88.06.2022.121-126
B. Belan, M. Dzevenko, R. Gladyshevskii, M. Daszkiewicz
Сrystal structure of the TmNi5 compound has been investigated by means of X-ray single crystal method (Oxford Diffraction X’calibur four-circle diffractometer, MoKα radiation) for the first time: CaCu5-type structure, Pearson symbol hP6, space group P6/mmm, a = 4.8684(12), c = 3.9541(7) Å, R1 = 0.0529, wR2 = 0.1835 for 80 reflections. Similarly to intermetallic compounds with high transition metal content, atoms in the title structure have rather high coordination numbers: 20 for thulium and 12 for nickel.
首次用X射线单晶法(牛津衍射X’口径四圆衍射仪，MoKα辐射)研究了TmNi5化合物的Сrystal结构:cacu5型结构，Pearson符号hP6，空间群P6/mmm, a = 4.8684(12)， c = 3.9541(7) Å， R1 = 0.0529, wR2 = 0.1835。与过渡金属含量高的金属间化合物类似，标题结构中的原子具有相当高的配位数:铥为20，镍为12。
{"title":"CRYSTAL STRUCTURE OF THE TmNi5","authors":"B. Belan, M. Dzevenko, R. Gladyshevskii, M. Daszkiewicz","doi":"10.33609/2708-129x.88.06.2022.121-126","DOIUrl":"https://doi.org/10.33609/2708-129x.88.06.2022.121-126","url":null,"abstract":"Сrystal structure of the TmNi5 compound has been investigated by means of X-ray single crystal method (Oxford Diffraction X’calibur four-circle diffractometer, MoKα radiation) for the first time: CaCu5-type structure, Pearson symbol hP6, space group P6/mmm, a = 4.8684(12), c = 3.9541(7) Å, R1 = 0.0529, wR2 = 0.1835 for 80 reflections. Similarly to intermetallic compounds with high transition metal content, atoms in the title structure have rather high coordination numbers: 20 for thulium and 12 for nickel.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83344152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-27DOI: 10.33609/2708-129x.88.06.2022.127-136
Y. Davydenko, V. Pavlenko, I. Fritsky, O. Vynohradov
The synthesis and characterization of mononuclear Co(II) complex based on 3,5-dimethyl-4-amino-1H-pyrazole are reported. IR and UV/Vis spectroscopy characterization of the complex are described. The synthesis, results of IR, NMR spectroscopy and elemental analysis of 3,5-dimethyl-4-amino-1H-pyrazole are also reported. X-ray analysis of [Co(C5H9N3)2Cl2] complex reveals that the cobalt atom has a tetrahedral coordination environment formed by two nitrogen atoms belonging to the two 3,5-dimethyl-4-amino-1H-pyrazole ligands [Co1–N1 = 2.005(3) and Co1–N5 = 2.006(3)Å] and two chlorine atoms [Co1–Cl2 = 2.2400(11) and Co1–Cl1 2.2863(12) Å]. In the crystal structure the molecules are linked through intermolecular (N–H···N, N–H···Cl) and intramolecular non-classical (С–H···Cl) hydrogen bonds. Hirshfeld surface analysis of the intermolecular contacts reveals that the most important contributions for the crystal packing are from H···H (47.1%) and H···Cl/Cl···H (28.5%) contacts.
{"title":"SYNTHESIS, X-RAY CRYSTAL STRUCTURE, SPECTROSCOPIC CHARACTERIZATION AND HIRSHFELD SURFACE ANALYSIS OF DICHLORO-BIS(3,5-DIMETHYL-4-AMINO-1H-PYRAZOLE) COBALT(II)","authors":"Y. Davydenko, V. Pavlenko, I. Fritsky, O. Vynohradov","doi":"10.33609/2708-129x.88.06.2022.127-136","DOIUrl":"https://doi.org/10.33609/2708-129x.88.06.2022.127-136","url":null,"abstract":"The synthesis and characterization of mononuclear Co(II) complex based on 3,5-dimethyl-4-amino-1H-pyrazole are reported. IR and UV/Vis spectroscopy characterization of the complex are described. The synthesis, results of IR, NMR spectroscopy and elemental analysis of 3,5-dimethyl-4-amino-1H-pyrazole are also reported. X-ray analysis of [Co(C5H9N3)2Cl2] complex reveals that the cobalt atom has a tetrahedral coordination environment formed by two nitrogen atoms belonging to the two 3,5-dimethyl-4-amino-1H-pyrazole ligands [Co1–N1 = 2.005(3) and Co1–N5 = 2.006(3)Å] and two chlorine atoms [Co1–Cl2 = 2.2400(11) and Co1–Cl1 2.2863(12) Å]. In the crystal structure the molecules are linked through intermolecular (N–H···N, N–H···Cl) and intramolecular non-classical (С–H···Cl) hydrogen bonds. Hirshfeld surface analysis of the intermolecular contacts reveals that the most important contributions for the crystal packing are from H···H (47.1%) and H···Cl/Cl···H (28.5%) contacts.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77024736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-24DOI: 10.33609/2708-129x.88.05.2022.37-68
Y. Dzyazko, Yevhen Kolomiiets
A literature analysis was conducted with sources that describe non-carbonized plant materials (in particular, cellulose from various plants and its derivatives) as sorbents for toxic ions (Cr3+, Cd2+, Cu2+, Pb2+, Ni2+, etc.) and organic compounds, including oil products. The advantage of plant-based non-carbonized raw materials and sorption materials based on them is the ease of obtaining them from cheap and available plant materials (often from agricultural waste), while the absorbed oil products can be separated from such sorbents by pressing, and the sorbents can be reused. The disadvantage is a different composition, depending on the region of growth. The use of inexpensive materials as a matrix for a composite sorbent makes it possible to widely use such material for post-cleaning and/or as the main method of cleaning aqueous solutions for consumer needs. In particular, the addition of finely dispersed inorganic compounds (in particular, graphene oxides) and organic modifiers to non-carbonized plant material for functionalization of its surface was analyzed. Surface modification gives the sorbent hydrophobic properties and/or results in a composite sorbent having a higher sorption capacity (compared to unmodified sorbents) in relation to target pollutants. The study authors suggest using fatty acids, zinc oxide, polysiloxanes, trimethylamine and other compounds as modifiers. The impact of the porous structure of cellulose on its properties as an element of a composite sorbent is also considered. The presence of functional groups in plant materials, in particular in biopolymers, allows them to be used as cheap anion exchangers. To increase the number of ion-exchange groups, the authors of the research suggest functionalizing the surface, which leads to an increase in the number, for example, of sulphatic groups, which in turn increases the ion-exchange capacity of such an ion-exchange material or a composite based on it. When using modified hydrophobic biosorbents to remove oil and oil products from water surfaces, it is possible to regenerate the sorbents mechanically, i.e. without reagents. This provides the possibility of multiple use of biosorbents on one side and the possible complete extraction of valuable products sorbed hydrocarbons.
{"title":"SORBENTS BASED ON NON-CARBONIZED VEGETABLE RAW MATERIALS","authors":"Y. Dzyazko, Yevhen Kolomiiets","doi":"10.33609/2708-129x.88.05.2022.37-68","DOIUrl":"https://doi.org/10.33609/2708-129x.88.05.2022.37-68","url":null,"abstract":"A literature analysis was conducted with sources that describe non-carbonized plant materials (in particular, cellulose from various plants and its derivatives) as sorbents for toxic ions (Cr3+, Cd2+, Cu2+, Pb2+, Ni2+, etc.) and organic compounds, including oil products. The advantage of plant-based non-carbonized raw materials and sorption materials based on them is the ease of obtaining them from cheap and available plant materials (often from agricultural waste), while the absorbed oil products can be separated from such sorbents by pressing, and the sorbents can be reused. The disadvantage is a different composition, depending on the region of growth. The use of inexpensive materials as a matrix for a composite sorbent makes it possible to widely use such material for post-cleaning and/or as the main method of cleaning aqueous solutions for consumer needs. In particular, the addition of finely dispersed inorganic compounds (in particular, graphene oxides) and organic modifiers to non-carbonized plant material for functionalization of its surface was analyzed. \u0000Surface modification gives the sorbent hydrophobic properties and/or results in a composite sorbent having a higher sorption capacity (compared to unmodified sorbents) in relation to target pollutants. The study authors suggest using fatty acids, zinc oxide, polysiloxanes, trimethylamine and other compounds as modifiers. The impact of the porous structure of cellulose on its properties as an element of a composite sorbent is also considered. The presence of functional groups in plant materials, in particular in biopolymers, allows them to be used as cheap anion exchangers. To increase the number of ion-exchange groups, the authors of the research suggest functionalizing the surface, which leads to an increase in the number, for example, of sulphatic groups, which in turn increases the ion-exchange capacity of such an ion-exchange material or a composite based on it. \u0000When using modified hydrophobic biosorbents to remove oil and oil products from water surfaces, it is possible to regenerate the sorbents mechanically, i.e. without reagents. This provides the possibility of multiple use of biosorbents on one side and the possible complete extraction of valuable products sorbed hydrocarbons.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75379712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：