Pub Date : 2022-06-24DOI: 10.33609/2708-129x.88.05.2022.3-14
N. Ivakha, O. Berezhnytska, O. Rohovtsov, O. Trunova, S. Smola
The metal polymers based on mono- and heteroligand β-diketonate complexes of Yb(III) with 2,7-dimethyl-octen-1-dione-3,5, 2,6-dimethyl-heptene-1-dione-3, 5 and with phenanthroline was synthesized. It has been defined that the coordination environment of the central ion remains unchanged during radical polymerization. The shape and position of the bands in the electronic absorption spectra are similar to the corresponding monomeric β-diketonate metal complexes, and slight shifts indicate deformation of the elementary unit of the metal polymer during the formation of the polymer chain. It is shown that the polymerization process lead to an increasing in the thermal stability of polymer complexes in comparison with monomeric analogues. An increase in the emission of metal polymers in comparison with monomeric complexes was established by the method of luminescent spectroscopy, which is due to energy, steric, and structural-mechanical factors.
{"title":"INVESTIGATION OF NEW POLYMER COMPLEXES BASED ON Yb(III) β-DIKETONATES","authors":"N. Ivakha, O. Berezhnytska, O. Rohovtsov, O. Trunova, S. Smola","doi":"10.33609/2708-129x.88.05.2022.3-14","DOIUrl":"https://doi.org/10.33609/2708-129x.88.05.2022.3-14","url":null,"abstract":"The metal polymers based on mono- and heteroligand β-diketonate complexes of Yb(III) with 2,7-dimethyl-octen-1-dione-3,5, 2,6-dimethyl-heptene-1-dione-3, 5 and with phenanthroline was synthesized. It has been defined that the coordination environment of the central ion remains unchanged during radical polymerization. The shape and position of the bands in the electronic absorption spectra are similar to the corresponding monomeric β-diketonate metal complexes, and slight shifts indicate deformation of the elementary unit of the metal polymer during the formation of the polymer chain. It is shown that the polymerization process lead to an increasing in the thermal stability of polymer complexes in comparison with monomeric analogues. An increase in the emission of metal polymers in comparison with monomeric complexes was established by the method of luminescent spectroscopy, which is due to energy, steric, and structural-mechanical factors.","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":"79429428","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.88.05.2022.25-36
M. Moroz, P. Demchenko, Myroslava Prohorenko, Ludmila Soliak, Serhii Prohorenko, O. Reshetnyak
The synthesis of thermodynamically stable phases of the Ag9GaSe6–Ag8GeSe6 (І) system at T<600 K were performed in the electrochemical cells (ECCs): (−) С | Ag | SЕ | R(Ag+) | PЕ | С (+), where C is graphite, Ag is the left (negative) electrode, SE is the purely Ag+ ion conducting solid electrolyte (Ag2GeS3-glass), PE is the right (positive) electrode, and R(Ag+) is the region of PE that contact with SE. PEs of ECCs were prepared from finely ground non-equilibrium mixtures of the compounds (Ag9GaSe6)1–х and (Ag8GeSe6)х, х=0.05, 0.1, 0.2, … , 0.9. Shifted from the left electrode to the R(Ag+) region for thermodynamic reasons Ag+ ions acted as the nucleation centers for the equilibrium phases of the x compositions, that is as the catalysts for reconstruction of the metastable mixtures of ternary compounds. The reproducibility of the EMF vs T dependences in the heating-cooling cycles is a result of the completion of reconstruction in the R(Ag+) region. Experimental dependences EMF vs T of ECCs with PE of mixtures of compounds indicated x, ECCs with PE of the Ag9GaSe6 and Ag8GeSe6 compounds are characterized by several discrete linear regions with different temperature intervals and functional dependences on temperature. The equations of the temperature dependences of the partial Gibbs energies of Ag-component in alloys for each discrete section of the specific x=0, 0.3, 0.5, 0.7, 1.0 were established for the first time and values of the standard partial functions were calculated. The bypass lines drawn through the points of EMF values of the cells at T=const for arbitrarily selected temperatures 298 K, 341 K, 395 K, 445 K, and 495 K in the range 280-500 K determine the phase composition of the equilibrium T-x space of (I) as: a solid solution based on compound Ag17GaGeSe12 in the range of 0.25≤x≤0.75, solid solutions based on the compounds (Ag9GaSe6)1–х for 0≤х≤0.15 and (Ag8GeSe6)х for 0.83≤х≤1, and two two-phase sections in the ranges 0.15≤x≤0.25 and 0.73≤x≤0.77. Some parameters of the crystal structure, the values of the total and ionic components of conductivity, the transfer numbers in the range of 290–380 K, and the integral values of the standard thermodynamic functions of the Ag17GaGeSe12 compound were established for the first time.
{"title":"THERMODYNAMICALLY STABLE PHASES OF THE Ag9GaSe6 – Ag8GeSe6 SYSTEM AT T<600 K AND THEIR PHYSICO-CHEMICAL PROPERTIES","authors":"M. Moroz, P. Demchenko, Myroslava Prohorenko, Ludmila Soliak, Serhii Prohorenko, O. Reshetnyak","doi":"10.33609/2708-129x.88.05.2022.25-36","DOIUrl":"https://doi.org/10.33609/2708-129x.88.05.2022.25-36","url":null,"abstract":"The synthesis of thermodynamically stable phases of the Ag9GaSe6–Ag8GeSe6 (І) system at T<600 K were performed in the electrochemical cells (ECCs): (−) С | Ag | SЕ | R(Ag+) | PЕ | С (+), where C is graphite, Ag is the left (negative) electrode, SE is the purely Ag+ ion conducting solid electrolyte (Ag2GeS3-glass), PE is the right (positive) electrode, and R(Ag+) is the region of PE that contact with SE. PEs of ECCs were prepared from finely ground non-equilibrium mixtures of the compounds (Ag9GaSe6)1–х and (Ag8GeSe6)х, х=0.05, 0.1, 0.2, … , 0.9. Shifted from the left electrode to the R(Ag+) region for thermodynamic reasons Ag+ ions acted as the nucleation centers for the equilibrium phases of the x compositions, that is as the catalysts for reconstruction of the metastable mixtures of ternary compounds. \u0000The reproducibility of the EMF vs T dependences in the heating-cooling cycles is a result of the completion of reconstruction in the R(Ag+) region. Experimental dependences EMF vs T of ECCs with PE of mixtures of compounds indicated x, ECCs with PE of the Ag9GaSe6 and Ag8GeSe6 compounds are characterized by several discrete linear regions with different temperature intervals and functional dependences on temperature. The equations of the temperature dependences of the partial Gibbs energies of Ag-component in alloys for each discrete section of the specific x=0, 0.3, 0.5, 0.7, 1.0 were established for the first time and values of the standard partial functions were calculated. The bypass lines drawn through the points of EMF values of the cells at T=const for arbitrarily selected temperatures 298 K, 341 K, 395 K, 445 K, and 495 K in the range 280-500 K determine the phase composition of the equilibrium T-x space of (I) as: a solid solution based on compound Ag17GaGeSe12 in the range of 0.25≤x≤0.75, solid solutions based on the compounds (Ag9GaSe6)1–х for 0≤х≤0.15 and (Ag8GeSe6)х for 0.83≤х≤1, and two two-phase sections in the ranges 0.15≤x≤0.25 and 0.73≤x≤0.77. Some parameters of the crystal structure, the values of the total and ionic components of conductivity, the transfer numbers in the range of 290–380 K, and the integral values of the standard thermodynamic functions of the Ag17GaGeSe12 compound were established for the first time.","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":"85584050","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 : 2022-05-25DOI: 10.33609/2708-129x.88.04.2022.113-122
V. Nikitenko, V. Kublanovsky, Yu. S. Yapontseva
In the work it is shown by the spectrophotometry method that depending on the concentration ratio of ligands [PPi4–]/[Cit3–] in the pyrophosphate-citrate electrolyte, cobalt (II) ions form not only citrate [Co(Cit)2]4– and pyrophosphate [Co(PPi)2]6–, but also polyligand complexes [Co(PPi)m(Cit)n]+2–(4m+3n). The composition of polyligand complexes [Co(PPi)Cit]5– was determined, and the equilibrium constant of the reaction of their formation and the constant of their stability were calculated (pβ=8.47). The dependence of the degree of formation of citrate, polyligand, and pyrophosphate complexes of cobalt (II) in the pyrophosphate-citrate electrolyte on the logarithm of the ratio of equilibrium concentrations of ligands is calculated.
{"title":"DETERMINATION OF POLYLIGAND COMPLEXES OF COBALT (II) WITH CITRATE AND PYROPHOSPHATE IONS","authors":"V. Nikitenko, V. Kublanovsky, Yu. S. Yapontseva","doi":"10.33609/2708-129x.88.04.2022.113-122","DOIUrl":"https://doi.org/10.33609/2708-129x.88.04.2022.113-122","url":null,"abstract":"In the work it is shown by the spectrophotometry method that depending on the concentration ratio of ligands [PPi4–]/[Cit3–] in the pyrophosphate-citrate electrolyte, cobalt (II) ions form not only citrate [Co(Cit)2]4– and pyrophosphate [Co(PPi)2]6–, but also polyligand complexes [Co(PPi)m(Cit)n]+2–(4m+3n). The composition of polyligand complexes [Co(PPi)Cit]5– was determined, and the equilibrium constant of the reaction of their formation and the constant of their stability were calculated (pβ=8.47). The dependence of the degree of formation of citrate, polyligand, and pyrophosphate complexes of cobalt (II) in the pyrophosphate-citrate electrolyte on the logarithm of the ratio of equilibrium concentrations of ligands is calculated.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91152923","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 : 2022-05-25DOI: 10.33609/2708-129x.88.04.2022.94-112
N. Ermokhina, A. Korzhak, D. Klymchuk, Alexander M Puziy, V. Grebennikov, N. Romanovska, Olexandr Shulzhenko, P. Manorik
Samples of mesoporous nanocrystalline titanium dioxide (anatase with a crystallite size of about 10 nm) were obtained by a modified sol-gel method in the presence of a template of dibenzo-18-crown-6 and small additives of surfactant (dodecylmethylethylammonium bromide) or ions of lanthanum (III) in butyl alcohol in combination with hydrothermal treatment at 175 °C for 24 hours followed by calcination in air at 500 °C for 4 hours. The photocatalytic activity of the obtained TiO2 samples was investigated in a model reaction of the photocatalytic release of H2 from an aqueous-ethanol mixture. It was found that in all cases the use of hydrothermal treatment significantly increases the photoactivity of the obtained sample, which in some cases is more than 3-4 times higher than the corresponding characteristic for commercial photocatalyst Evonik P25. The key effect of hydrothermal treatment on the increase of photoactivity of the samples is probably the consequence of a drastic increase in the treated samples of pore volume and diameter, as well as a decrease in the size of anatase crystallites. These changes (along with a significant increase in the specific surface area) are greater for samples obtained in the presence of La3+ ions. It is shown that samples of TiO2 microspheres obtained at the same concentrations of reagents in the reaction mixture show slightly higher photocatalytic activity than the corresponding lanthanum-stabilized samples of mesoporous TiO2 powders (micrometer-scale particles are not formed in the presence of lanthanum (III) ions). However, with an increasing concentration of reagents in the reaction mixture, the photocatalytic activity has the sample containing lanthanum. Probably, this can be explained by the high textural characteristics of the TiO2 sample in combination with the peculiarities of its morphology - the formation of secondary nanoparticles of agglomerated formations and the influence of La3+ ions. It is worth noting that the photocatalytic activity of TiO2 samples prepared in the presence of La3+ ions reduces as their specific surface area decreases.
{"title":"PHOTOCATALYTIC ACTIVITY OF MESOPOROUS TiO2 (ANATAS) IN THE REACTION OF HYDROGEN RELEASE FROM AQUEOUS-ETHANOLIC MIXTURE","authors":"N. Ermokhina, A. Korzhak, D. Klymchuk, Alexander M Puziy, V. Grebennikov, N. Romanovska, Olexandr Shulzhenko, P. Manorik","doi":"10.33609/2708-129x.88.04.2022.94-112","DOIUrl":"https://doi.org/10.33609/2708-129x.88.04.2022.94-112","url":null,"abstract":"Samples of mesoporous nanocrystalline titanium dioxide (anatase with a crystallite size of about 10 nm) were obtained by a modified sol-gel method in the presence of a template of dibenzo-18-crown-6 and small additives of surfactant (dodecylmethylethylammonium bromide) or ions of lanthanum (III) in butyl alcohol in combination with hydrothermal treatment at 175 °C for 24 hours followed by calcination in air at 500 °C for 4 hours. The photocatalytic activity of the obtained TiO2 samples was investigated in a model reaction of the photocatalytic release of H2 from an aqueous-ethanol mixture. It was found that in all cases the use of hydrothermal treatment significantly increases the photoactivity of the obtained sample, which in some cases is more than 3-4 times higher than the corresponding characteristic for commercial photocatalyst Evonik P25. The key effect of hydrothermal treatment on the increase of photoactivity of the samples is probably the consequence of a drastic increase in the treated samples of pore volume and diameter, as well as a decrease in the size of anatase crystallites. These changes (along with a significant increase in the specific surface area) are greater for samples obtained in the presence of La3+ ions. It is shown that samples of TiO2 microspheres obtained at the same concentrations of reagents in the reaction mixture show slightly higher photocatalytic activity than the corresponding lanthanum-stabilized samples of mesoporous TiO2 powders (micrometer-scale particles are not formed in the presence of lanthanum (III) ions). However, with an increasing concentration of reagents in the reaction mixture, the photocatalytic activity has the sample containing lanthanum. Probably, this can be explained by the high textural characteristics of the TiO2 sample in combination with the peculiarities of its morphology - the formation of secondary nanoparticles of agglomerated formations and the influence of La3+ ions. It is worth noting that the photocatalytic activity of TiO2 samples prepared in the presence of La3+ ions reduces as their specific surface area decreases.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88896664","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 : 2022-05-25DOI: 10.33609/2708-129x.88.04.2022.63-78
O. Bezdorozhev, I. Solodkyi, A. Ostroverkh, I. Morozov, Y. Ostroverkh, Y. Solonin
This work reports on the preparation and characterization of Sr2+-doped Ba7Nb4MoO20 powders prepared by a solid-state synthesis as promising materials for solid oxide fuel cells. The influence of synthesis parameters and strontium content (x = 0; 0.05; 0.10; 0.15; 0.20) on the phase composition and properties of (Ba1-xSrx)7Nb4MoO20 powders was studied. The results of the phase analysis show that (Ba1-xSrx)7Nb4MoO20 (x = 0; 0.05; 0.10) powders with a minimum amount of secondary phases can be obtained after at least three repeated synthesis cycles at 1060–1080 оС for 10 h. According to the laser diffraction analysis, the synthesized powders comprise particles with a polydisperse size distribution spreading from 0.05 μm to 12 μm and average particle size of 2.1 μm. Electron microscopy observations support these findings and demonstrate that the particles and their aggregates have rounded irregular shape. Moreover, it was found that the morphology and particle size of the powder does not depend on the strontium content. Doping (Ba1-xSrx)7Nb4MoO20 with 15 mol.% and 20 mol.% Sr2+ leads to the formation of a significant amount of secondary phases due to exceeding the solubility limit of strontium, thus making these compositions unsuitable for use in solid oxide fuel cells.
{"title":"SYNTHESIS AND CHARACTERIZATION OF (Ba1-хSrx)7Nb4MoO20 POWDERS FOR PROTON-CONDUCTING SOLID OXIDE FUEL CELLS","authors":"O. Bezdorozhev, I. Solodkyi, A. Ostroverkh, I. Morozov, Y. Ostroverkh, Y. Solonin","doi":"10.33609/2708-129x.88.04.2022.63-78","DOIUrl":"https://doi.org/10.33609/2708-129x.88.04.2022.63-78","url":null,"abstract":"This work reports on the preparation and characterization of Sr2+-doped Ba7Nb4MoO20 powders prepared by a solid-state synthesis as promising materials for solid oxide fuel cells. The influence of synthesis parameters and strontium content (x = 0; 0.05; 0.10; 0.15; 0.20) on the phase composition and properties of (Ba1-xSrx)7Nb4MoO20 powders was studied. The results of the phase analysis show that (Ba1-xSrx)7Nb4MoO20 (x = 0; 0.05; 0.10) powders with a minimum amount of secondary phases can be obtained after at least three repeated synthesis cycles at 1060–1080 оС for 10 h. According to the laser diffraction analysis, the synthesized powders comprise particles with a polydisperse size distribution spreading from 0.05 μm to 12 μm and average particle size of 2.1 μm. Electron microscopy observations support these findings and demonstrate that the particles and their aggregates have rounded irregular shape. Moreover, it was found that the morphology and particle size of the powder does not depend on the strontium content. Doping (Ba1-xSrx)7Nb4MoO20 with 15 mol.% and 20 mol.% Sr2+ leads to the formation of a significant amount of secondary phases due to exceeding the solubility limit of strontium, thus making these compositions unsuitable for use in solid oxide fuel cells.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86343296","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 : 2022-05-25DOI: 10.33609/2708-129x.88.04.2022.79-93
P. Torchyniuk, O. V’yunov, V. Vlasyuk, V. Kostylyov, A. Belous
The peculiarities of formation and properties of organiс-inorganic MAPbI3 perovskite films, obtained from solutions with different ratios of starting reagents (PbI2:MAI = 1:1,1:2, and 1:3), in the DMF and DMSO solvents, studied. As the PbI2:MAI ratio increases, the temperature of the formation of a single-phase MAPbI3 perovskite film also increases. The slight changes in the structural and electrophysical characteristics for perovskite films obtained at the different ratios of PbI2:MAI in DMF and DMSO were found. These changes are related to the solvent that is included in the crystalline structure of perovskite. In the same ratios of starting reagents, DMF is included in the structure of perovskite in a greater amount than DMSO.
{"title":"INFLUENCE OF THE SOLVENT AND THE RATIO OF STARTING REAGENTS ON THE PROPERTIES OF ORGANIC-INORGANIC PEROVSKITE MAPbI3","authors":"P. Torchyniuk, O. V’yunov, V. Vlasyuk, V. Kostylyov, A. Belous","doi":"10.33609/2708-129x.88.04.2022.79-93","DOIUrl":"https://doi.org/10.33609/2708-129x.88.04.2022.79-93","url":null,"abstract":"The peculiarities of formation and properties of organiс-inorganic MAPbI3 perovskite films, obtained from solutions with different ratios of starting reagents (PbI2:MAI = 1:1,1:2, and 1:3), in the DMF and DMSO solvents, studied. As the PbI2:MAI ratio increases, the temperature of the formation of a single-phase MAPbI3 perovskite film also increases. The slight changes in the structural and electrophysical characteristics for perovskite films obtained at the different ratios of PbI2:MAI in DMF and DMSO were found. These changes are related to the solvent that is included in the crystalline structure of perovskite. In the same ratios of starting reagents, DMF is included in the structure of perovskite in a greater amount than DMSO.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86886350","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 : 2022-04-28DOI: 10.33609/2708-129x.88.03.2022.28-39
Y. Dzyazko, L. Rozhdestvenska, A. Palchik, K. Kudelko, T. Yatsenko, L. Ponomarova
The theoretical approach, which allows us to control the formation of aggregates incorporated into porous matrixes has been developed and verified. It was established that the important parameter is the pH of a precipitator: the higher this value, the larger aggregates are formed. Based on the approach, a method of obtaining the composite based on naturalclinoptilolite-based zeolite containing nanoparticles of hydrated iron oxide has been developed. The porous structure of composite sorbents has been studied. The sorbents were investigated using XRD, TEM, SEM methods. Weakly basic precipitator has been recommended in order to obtain the nanosized aggregates of the modifier. During the synthesis, porous structure of the zeolite substrate is transformed. Acid activation promotes the development of the sorbent surface, which leads to the dissolution of the elements present in clinoptilolite. The increase in the surface of the modified sorbents is due to highly ordered pores in the range of 1-2 nm, as the microporosity decreases after acid activation. Impurities block ordered pores, and activation opens them. But after modification, these pores are partially blocked. This is probably caused by the precipitation of oxide dissolution products in alkaline media. Despite this fact, all the obtained samples of composite sorbents are mostly mesoporous. Sorption of di- and trivalent cations from multicomponent solution was studied. It was found that the presence of a nanoscale modifier accelerates ion absorption. The modified zeolite improves sorption of metals, which are not related to d-elements. The removal degree of Pb2+ ions reaches 97%. The isotherms of Pb2+sorption are fitted with Freundlich model. In addition to the lead extraction from aqueous solutions, the sorbent could be also recommended for water softening.
{"title":"ZEOLITE-BASED NANOCOMPOSITE MODIFIED WITH HYDRATED IRON OXIDE (III) FOR REMOVAL OF HEAVY METALS","authors":"Y. Dzyazko, L. Rozhdestvenska, A. Palchik, K. Kudelko, T. Yatsenko, L. Ponomarova","doi":"10.33609/2708-129x.88.03.2022.28-39","DOIUrl":"https://doi.org/10.33609/2708-129x.88.03.2022.28-39","url":null,"abstract":"The theoretical approach, which allows us to control the formation of aggregates incorporated into porous matrixes has been developed and verified. It was established that the important parameter is the pH of a precipitator: the higher this value, the larger aggregates are formed. Based on the approach, a method of obtaining the composite based on naturalclinoptilolite-based zeolite containing nanoparticles of hydrated iron oxide has been developed. The porous structure of composite sorbents has been studied. The sorbents were investigated using XRD, TEM, SEM methods. Weakly basic precipitator has been recommended in order to obtain the nanosized aggregates of the modifier. During the synthesis, porous structure of the zeolite substrate is transformed. Acid activation promotes the development of the sorbent surface, which leads to the dissolution of the elements present in clinoptilolite. The increase in the surface of the modified sorbents is due to highly ordered pores in the range of 1-2 nm, as the microporosity decreases after acid activation. Impurities block ordered pores, and activation opens them. But after modification, these pores are partially blocked. This is probably caused by the precipitation of oxide dissolution products in alkaline media. Despite this fact, all the obtained samples of composite sorbents are mostly mesoporous. Sorption of di- and trivalent cations from multicomponent solution was studied. It was found that the presence of a nanoscale modifier accelerates ion absorption. The modified zeolite improves sorption of metals, which are not related to d-elements. The removal degree of Pb2+ ions reaches 97%. The isotherms of Pb2+sorption are fitted with Freundlich model. In addition to the lead extraction from aqueous solutions, the sorbent could be also recommended for water softening.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89844269","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 : 2022-04-28DOI: 10.33609/2708-129x.88.03.2022.3-27
S. Orysyk, V. Pekhnyo, V. Orysyk, Yu. L. Zborovskii, P. Borovyk, V. Mykhailo
In the second part of the analytical review, the influence of polydentate and N-allyl-substituted thiamides on the course of complexation reactions with platinum metal ions and Ag(I) was analyzed. The potential of the obtained coordination compounds for their application in medical and analytical chemistry is also demonstrated. The presented results are obtained on the basis of joint research performed in the Department of "Chemistry of Complex Compounds" of the V.I. Vernadsky Institute of General and Inorganic Chemistry NAS of Ukraine together with the staff of the Department of “Chemistry of Heterocyclic Compounds” of the Institute of Organic Chemistry NAS of Ukraine. The example of the reaction of polydentate thioureas with metal ions shows that the increase in functional groups does not always lead to their simultaneous coordination with metal ions. For example, the migration of double bonds, which is characteristic of H2 L5 thioureas, contributes to the stiffness of heterocycles, which in turn reduces the dentat capacity of these thioureas as ligands, despite the localization of donor atoms in a favorable position for metallocycle formation. In addition, an increase in the number of donor centers in the thioamide molecule can lead to their intramolecular rearrangement under conditions of complexation, and to the occurs of redox reactions. It has been shown that the formation of a π coordination bond involved in the formation of a six-membered chelated metalocycle occurs only when, together with the C=C allyl moiety, other donor atoms of the organic ligand are at an unfavorable geometric location for metalocycle formation. Otherwise, the allyl group does not participate in the coordination to the central metal ion. A characteristic indicator of the formation of the π coordination bond is the splitting of the C3 H2 signal of allylic group protons in 1 H NMR spectra into two doublets with the same spin-spin interaction constant, as well as high-frequency shift of absorption bands of valence vibrations νas(CH)allyl, νs (CH) allyl in the IR spectra of π,n-chelate complexes.It was found that regardless of the stoichiometry of the starting components, the reaction of N-allyl-substituted thioamides HL10-12 with platinum metal ions leads to the formation of complexes only in the ratio M:L=1:1, due to the strong "trans-effect" of the allylic fragment. It was found that a number of n,π-chelate complexes of palladium(II) and platinum(II) with general formula [Pd/Pt(HL10-12)Hal2 ] (Hal = Cl-, Br- , I- ), which are structurally analogous to the known antitumor agent cisplatin, show effective antitumor action: antiproliferative, cytotoxic, anti-metastatic, proapoptotic. However, unlike cisplatin, they have proven to be much more effective: they are stable over a wide pH range; have the ability to overcome the resistance of pathogenic cells to the action of antitumor agents and show a wider range of action. The method of molecular docking was used to study
{"title":"FUNDAMENTAL ASPECTS OF COORDINATION CHEMISTRY OF TRANSITION METALS WITH FUNCTIONALLY SUBSTITUTED THIOAMIDES (PART 2)","authors":"S. Orysyk, V. Pekhnyo, V. Orysyk, Yu. L. Zborovskii, P. Borovyk, V. Mykhailo","doi":"10.33609/2708-129x.88.03.2022.3-27","DOIUrl":"https://doi.org/10.33609/2708-129x.88.03.2022.3-27","url":null,"abstract":"In the second part of the analytical review, the influence of polydentate and N-allyl-substituted thiamides on the course of complexation reactions with platinum metal ions and Ag(I) was analyzed. The potential of the obtained coordination compounds for their application in medical and analytical chemistry is also demonstrated. The presented results are obtained on the basis of joint research performed in the Department of \"Chemistry of Complex Compounds\" of the V.I. Vernadsky Institute of General and Inorganic Chemistry NAS of Ukraine together with the staff of the Department of “Chemistry of Heterocyclic Compounds” of the Institute of Organic Chemistry NAS of Ukraine. The example of the reaction of polydentate thioureas with metal ions shows that the increase in functional groups does not always lead to their simultaneous coordination with metal ions. For example, the migration of double bonds, which is characteristic of H2 L5 thioureas, contributes to the stiffness of heterocycles, which in turn reduces the dentat capacity of these thioureas as ligands, despite the localization of donor atoms in a favorable position for metallocycle formation. In addition, an increase in the number of donor centers in the thioamide molecule can lead to their intramolecular rearrangement under conditions of complexation, and to the occurs of redox reactions. It has been shown that the formation of a π coordination bond involved in the formation of a six-membered chelated metalocycle occurs only when, together with the C=C allyl moiety, other donor atoms of the organic ligand are at an unfavorable geometric location for metalocycle formation. Otherwise, the allyl group does not participate in the coordination to the central metal ion. A characteristic indicator of the formation of the π coordination bond is the splitting of the C3 H2 signal of allylic group protons in 1 H NMR spectra into two doublets with the same spin-spin interaction constant, as well as high-frequency shift of absorption bands of valence vibrations νas(CH)allyl, νs (CH) allyl in the IR spectra of π,n-chelate complexes.It was found that regardless of the stoichiometry of the starting components, the reaction of N-allyl-substituted thioamides HL10-12 with platinum metal ions leads to the formation of complexes only in the ratio M:L=1:1, due to the strong \"trans-effect\" of the allylic fragment. It was found that a number of n,π-chelate complexes of palladium(II) and platinum(II) with general formula [Pd/Pt(HL10-12)Hal2 ] (Hal = Cl-, Br- , I- ), which are structurally analogous to the known antitumor agent cisplatin, show effective antitumor action: antiproliferative, cytotoxic, anti-metastatic, proapoptotic. However, unlike cisplatin, they have proven to be much more effective: they are stable over a wide pH range; have the ability to overcome the resistance of pathogenic cells to the action of antitumor agents and show a wider range of action. The method of molecular docking was used to study","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79804048","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 : 2022-04-28DOI: 10.33609/2708-129x.88.03.2022.28-35
Yuriy Pirskyy, F. Manilevich, A. Kutsyi
Sodium borohydride hydrolysisis one of the most productive hydrogengeneration methods, which can be used, inparticular, to power fuel cells with a hydrogenanode. In alkaline solutions, the interaction of NaBH4 with water practically does not occur, which makes it possible to store such solutions for a longtime. However, in the presence of catalysts, the borohydride hydrolysis reaction actively proceeds at room temperature with the formation of hydrogenand sodium metaborate. More than 300 homogeneous and heterogeneous catalysts for the hydrolysis of sodium borohydride are known, among which the most active metal catalysts are nanodispersed rhodium, ruthenium, and platinum immobilized on various substrates. The activity of such catalysts depends on the conditions of the reduction and immobilization of metals, the nature of used precursors, the amount of active phase of the catalyst, and the type of substrate. In this work, platinum catalysts immobilized on several substrates are developed, and the regularities of hydrolysis of sodium borohydride in alkaline solution when using such catalysts in flowing flat and cylindrical reactors are investigated. Using various methods, platinum was deposited on carbon black and carbon cloth, onactivated granular carbon, on titanium crumb, and on synthetic cordierite of honey combstructure with surface, previously modified by alumina. It is shown that nanodisperse platinum catalysts immobilized on carbon black and carbon cloth and especially on synthetic cordierite of cellular structure with surface previously modified by Al2O3 layer are active and reliable. The average rate of hydrogen evolution during hydrolysis of NaBH4 on such catalysts increases with increasing flow rate of its solution through the reactor, but the degree of conversion of sodium borohydride decreases due to the reduced duration of contact of the solution with the catalyst. Nanodisperse platinum catalysts on surface-modified cordierite provide a highandstable rate of hydrogengeneration with moderate heating of NaBH4 solution (60±5°C). The use of hydrogen generators with such catalysts in combination with fuel cell batteries is promising for the creation of autonomous powers ources.
{"title":"REGULARITIES OF HYDROGEN GENERATION BY HYDROLYSIS OF SODIUM BOROHYDRIDE ON IMMOBILIZED PLATINUM CATALYSTS","authors":"Yuriy Pirskyy, F. Manilevich, A. Kutsyi","doi":"10.33609/2708-129x.88.03.2022.28-35","DOIUrl":"https://doi.org/10.33609/2708-129x.88.03.2022.28-35","url":null,"abstract":"Sodium borohydride hydrolysisis one of the most productive hydrogengeneration methods, which can be used, inparticular, to power fuel cells with a hydrogenanode. In alkaline solutions, the interaction of NaBH4 with water practically does not occur, which makes it possible to store such solutions for a longtime. However, in the presence of catalysts, the borohydride hydrolysis reaction actively proceeds at room temperature with the formation of hydrogenand sodium metaborate. More than 300 homogeneous and heterogeneous catalysts for the hydrolysis of sodium borohydride are known, among which the most active metal catalysts are nanodispersed rhodium, ruthenium, and platinum immobilized on various substrates. The activity of such catalysts depends on the conditions of the reduction and immobilization of metals, the nature of used precursors, the amount of active phase of the catalyst, and the type of substrate. In this work, platinum catalysts immobilized on several substrates are developed, and the regularities of hydrolysis of sodium borohydride in alkaline solution when using such catalysts in flowing flat and cylindrical reactors are investigated. Using various methods, platinum was deposited on carbon black and carbon cloth, onactivated granular carbon, on titanium crumb, and on synthetic cordierite of honey combstructure with surface, previously modified by alumina. It is shown that nanodisperse platinum catalysts immobilized on carbon black and carbon cloth and especially on synthetic cordierite of cellular structure with surface previously modified by Al2O3 layer are active and reliable. The average rate of hydrogen evolution during hydrolysis of NaBH4 on such catalysts increases with increasing flow rate of its solution through the reactor, but the degree of conversion of sodium borohydride decreases due to the reduced duration of contact of the solution with the catalyst. Nanodisperse platinum catalysts on surface-modified cordierite provide a highandstable rate of hydrogengeneration with moderate heating of NaBH4 solution (60±5°C). The use of hydrogen generators with such catalysts in combination with fuel cell batteries is promising for the creation of autonomous powers ources.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84870984","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 : 2022-04-28DOI: 10.33609/2708-129x.88.03.2022.48-60
K. Pershina
The impact of warfare in one region on other regions is shown using the base fundamental thermodynamics laws and trends of decreasing entropy. The physical sense of the negentropy is described use of the principles of chemical thermodynamics. A phenomenological model for the description impact of warfare on the ecological part of the region is proposed. According to this model, a system without plants, with destroyed soils, can't be alive without external factors. Based on thermodynamic differences between turbulent and laminar flows, the capability of the zones formation with an absence of the ability to any own functioning outside zone with military actions is shown. With the rising number of influencing factors, especially in large areas, the probability of narrowing and loss of zones with a stable state as in the region with military action but in neighboring regions increases.
{"title":"WHAT IS NEGATIVE ENTROPY AND HOW DOES IT AFFECT THE SUSTAINABILITY OF REGIONS DURING THE WARFARE","authors":"K. Pershina","doi":"10.33609/2708-129x.88.03.2022.48-60","DOIUrl":"https://doi.org/10.33609/2708-129x.88.03.2022.48-60","url":null,"abstract":"The impact of warfare in one region on other regions is shown using the base fundamental thermodynamics laws and trends of decreasing entropy. The physical sense of the negentropy is described use of the principles of chemical thermodynamics. A phenomenological model for the description impact of warfare on the ecological part of the region is proposed. According to this model, a system without plants, with destroyed soils, can't be alive without external factors. Based on thermodynamic differences between turbulent and laminar flows, the capability of the zones formation with an absence of the ability to any own functioning outside zone with military actions is shown. With the rising number of influencing factors, especially in large areas, the probability of narrowing and loss of zones with a stable state as in the region with military action but in neighboring regions increases.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74102779","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：