Pub Date : 2023-05-10DOI: 10.18524/2304-0947.2023.1(84).277052
T. Koksharova, Y. Slyvka, O. A. Savchenko, T. Mandzii
The new 5-sulfosalicylato cobalt coordination compound [Co(Bhz)3]3(HSSal)3×7.5Н2О (where Bhz – benzohydrazide, HSSal2– – 5-sulfosalicylate anion) has been synthesized and studied by elemental analysis, IR and diffuse reflectance spectroscopy and single-crystal X‑ray diffraction.
{"title":"SYNTHESIS AND STRUCTURE OF COORDINATION COMPOUND OF COBALT(II) 5-SULFOSALICYLATE WITH BENZOHYDRAZIDE","authors":"T. Koksharova, Y. Slyvka, O. A. Savchenko, T. Mandzii","doi":"10.18524/2304-0947.2023.1(84).277052","DOIUrl":"https://doi.org/10.18524/2304-0947.2023.1(84).277052","url":null,"abstract":"The new 5-sulfosalicylato cobalt coordination compound [Co(Bhz)3]3(HSSal)3×7.5Н2О (where Bhz – benzohydrazide, HSSal2– – 5-sulfosalicylate anion) has been synthesized and studied by elemental analysis, IR and diffuse reflectance spectroscopy and single-crystal X‑ray diffraction.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83321162","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 : 2023-05-10DOI: 10.18524/2304-0947.2023.1(84).277064
A. Tymchuk, O. Streltsova, A. D. Purich
The modern technologies of the adsorption processes are searching of the new, ecologically friendly adsorbents as natural polymers – chitin and chitosan. Chitin and chitosan adsorbents have high adsorption ability in relation to mineral oils, dyes, alcohols, phenols and heavy metals. The basic natural sources of chitin are the shells of crustacean and the biomass of fungus` mycelium. Chitin provides the mechanical strength of the structure without rigid bonds between microfibrilles, that allows to keep the certain elasticity of a cellular wall. The submitted researches are devoted to studying adsorption activity of chitosan and chitin received from the shells of crustacean in relation to of organic polutants. It was shown that the use of chitin and chitosan polymers of natural origin as sorbents is a worthy alternative to synthetic sorbents. Natural sorbents have advantages due to environmental friendliness, safety and biodegradability. It has been experimentally proven that the investigated natural polymers absorb organic pollutants with an efficiency of up to 98%. The nature of the polymer and the method of its introduction affect the effectiveness of the sorption process. Sorption can be described using the Langmuir and Freundlich sorption equations. In order to clarify the sorption mechanism, the temperature dependence of the process was studied. In all cases, the sorption of vaseline oil decreases with increasing temperature, which suggests a physical mechanism of sorption. Sorption occurs due to dispersion interaction. Hydrophobic interactions between molecules of organic substances and non-polar regions of chitosan macromolecules make a certain contribution to the mechanism of sorption of the studied substances. The effective sorption capacity of chitosan is explained not only by its physical and chemical properties, the developed structure of micropores, but also by the method of adding the sorbent. Apolar liquids are sorbed due to hydrophobic interaction, chitosan forms hydrogen bonds that can bind polar components in the composition. The high sorption activity of chitosan in relation to organic pollutants, surface-active substances, heavy metals, dyes, its renewability and ability to biological decomposition allow it to be considered a sufficiently effective and practically universal sorbent.
{"title":"SORPTION OF APOLAR LIQUIDS BY NATURAL HIGH MOLECULAR COMPOUNDS","authors":"A. Tymchuk, O. Streltsova, A. D. Purich","doi":"10.18524/2304-0947.2023.1(84).277064","DOIUrl":"https://doi.org/10.18524/2304-0947.2023.1(84).277064","url":null,"abstract":"The modern technologies of the adsorption processes are searching of the new, ecologically friendly adsorbents as natural polymers – chitin and chitosan. Chitin and chitosan adsorbents have high adsorption ability in relation to mineral oils, dyes, alcohols, phenols and heavy metals. The basic natural sources of chitin are the shells of crustacean and the biomass of fungus` mycelium. Chitin provides the mechanical strength of the structure without rigid bonds between microfibrilles, that allows to keep the certain elasticity of a cellular wall.\u0000The submitted researches are devoted to studying adsorption activity of chitosan and chitin received from the shells of crustacean in relation to of organic polutants.\u0000It was shown that the use of chitin and chitosan polymers of natural origin as sorbents is a worthy alternative to synthetic sorbents. Natural sorbents have advantages due to environmental friendliness, safety and biodegradability. It has been experimentally proven that the investigated natural polymers absorb organic pollutants with an efficiency of up to 98%. The nature of the polymer and the method of its introduction affect the effectiveness of the sorption process. Sorption can be described using the Langmuir and Freundlich sorption equations.\u0000In order to clarify the sorption mechanism, the temperature dependence of the process was studied. In all cases, the sorption of vaseline oil decreases with increasing temperature, which suggests a physical mechanism of sorption. Sorption occurs due to dispersion interaction. Hydrophobic interactions between molecules of organic substances and non-polar regions of chitosan macromolecules make a certain contribution to the mechanism of sorption of the studied substances.\u0000The effective sorption capacity of chitosan is explained not only by its physical and chemical properties, the developed structure of micropores, but also by the method of adding the sorbent. Apolar liquids are sorbed due to hydrophobic interaction, chitosan forms hydrogen bonds that can bind polar components in the composition. The high sorption activity of chitosan in relation to organic pollutants, surface-active substances, heavy metals, dyes, its renewability and ability to biological decomposition allow it to be considered a sufficiently effective and practically universal sorbent.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80955424","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 : 2023-05-10DOI: 10.18524/2304-0947.2023.1(84).277056
E. Streltsova, O. Voliuvach, A. Tymchuk, V. V. Menchuk
A colloid-chemical approach was used to describe the process of surface concentration of Tweens (Tw-60, Tw-80), sodium dodecylsulfate (SDDS), chloride dodecylammonium (HDDA) from multicomponent aqueous solutions. The possibility of increasing the degree of flotation isolation of SDDS and HDDA when they are together in a solution with Tweens in the presence of polyvinyl alcohol (PVA) has been confirmed. During the flotation treatment of binary solutions of ionic (HDDA, SDDS) and nonionic (Tw-60, Tw-80) surfactants of different composition, the degree of flotation isolation increases be 10–25% on average when compared with their isolation from individual solutions. The addition of PVA, which is used as high molecular weight reagent, in the form of a 0.15–1.0% aqueous solution in the amount of 0.5–2.0 cm3 per 25–50 cm3 of a mixed surfactants solution lead to increase the degree of isolation of Tweens and SDDS. According to Rosen’s model, the composition of mixed adsorption layers at the boundary between the solution and air phases was calculated, as well as the parameters of intermolecular interaction in adsorption layers. For all mixtures of surfactants at any ratio of components, adsorption layers are formed, most of which are enriched with more surface-active Tw-60 and Tw-80. With the composition of the mixture of SDDS-Tw-60 n(SDDS): n(Tw-60)=0.7:0.3, almost equimolar adsorption layers are formed. At different mole rations of surfactants in mixed systems in solution, the molar fraction of Tw-60 in the adsorption layers of the HDDA-Tw-60 mixtures is greater than that of the SDDS-Tw-60 mixtures. The value βσ depends on the type and composition of the mixture, the nature of the surfactant. This effect is most pronounced at a high content n(Tween) = 0.7 in the solution (here the maximum values (by absolute value) of the intermolecular interaction parameter are observed. The expediency of using the parameter of surfactants in mixed adsorption layers to predict their surface concentration during isolation from multicomponent aqueous solutions and wastewater is shown.
{"title":"INFLUENCE OF POLYVINIL ALCOHOL ON THE SURFACE PROPERTIES OF IONOGENIC SURFACTANT – TWEEN MIXTURES","authors":"E. Streltsova, O. Voliuvach, A. Tymchuk, V. V. Menchuk","doi":"10.18524/2304-0947.2023.1(84).277056","DOIUrl":"https://doi.org/10.18524/2304-0947.2023.1(84).277056","url":null,"abstract":"A colloid-chemical approach was used to describe the process of surface concentration of Tweens (Tw-60, Tw-80), sodium dodecylsulfate (SDDS), chloride dodecylammonium (HDDA) from multicomponent aqueous solutions. The possibility of increasing the degree of flotation isolation of SDDS and HDDA when they are together in a solution with Tweens in the presence of polyvinyl alcohol (PVA) has been confirmed. During the flotation treatment of binary solutions of ionic (HDDA, SDDS) and nonionic (Tw-60, Tw-80) surfactants of different composition, the degree of flotation isolation increases be 10–25% on average when compared with their isolation from individual solutions. The addition of PVA, which is used as high molecular weight reagent, in the form of a 0.15–1.0% aqueous solution in the amount of 0.5–2.0 cm3 per 25–50 cm3 of a mixed surfactants solution lead to increase the degree of isolation of Tweens and SDDS.\u0000According to Rosen’s model, the composition of mixed adsorption layers at the boundary between the solution and air phases was calculated, as well as the parameters of intermolecular interaction in adsorption layers. For all mixtures of surfactants at any ratio of components, adsorption layers are formed, most of which are enriched with more surface-active Tw-60 and Tw-80. With the composition of the mixture of SDDS-Tw-60 n(SDDS): n(Tw-60)=0.7:0.3, almost equimolar adsorption layers are formed. At different mole rations of surfactants in mixed systems in solution, the molar fraction of Tw-60 in the adsorption layers of the HDDA-Tw-60 mixtures is greater than that of the SDDS-Tw-60 mixtures. The value βσ depends on the type and composition of the mixture, the nature of the surfactant. This effect is most pronounced at a high content n(Tween) = 0.7 in the solution (here the maximum values (by absolute value) of the intermolecular interaction parameter are observed. The expediency of using the parameter of surfactants in mixed adsorption layers to predict their surface concentration during isolation from multicomponent aqueous solutions and wastewater is shown.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"103 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85874964","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 : 2023-05-10DOI: 10.18524/2304-0947.2023.1(84).278141
R. Y. Khoma
In memory of Valentyna Fedorivna Sazonova (1943–2021)
{"title":"IN MEMORY OF VALENTYNA FEDORIVNA SAZONOVA (1943–2021)","authors":"R. Y. Khoma","doi":"10.18524/2304-0947.2023.1(84).278141","DOIUrl":"https://doi.org/10.18524/2304-0947.2023.1(84).278141","url":null,"abstract":"In memory of Valentyna Fedorivna Sazonova (1943–2021)","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"63 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80729696","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 : 2023-05-10DOI: 10.18524/2304-0947.2023.1(84).277055
V. Zinchenko, V. V. Menchuk, P. H. Doha
A correlation between acid-base properties and volatility parameters (temperature and enthalpy of vaporization) of fluorides of s-, p-, and d-metals was revealed. As a characteristic of acid-base properties, the basicity parameter proposed in the work, based on the size-charge characteristics of the ions that make up the compound, is taken. The value of the basicity parameter naturally decreases from fluorides of low-valent metals (I–III) to fluorides of highvalent metals (IV–VII). The indicated cation substitution results in a significant increase in the volatility of compounds, which is explained by a change in the type of crystal structure from ionic-covalent to molecular one typical for acid-type fluorides. Metal fluorides with intermediate values of the basicity parameter (Zr(IV), Hf(IV), Al(III)) are characterized by significantly higher values of temperature and evaporation enthalpy, that is, lower volatility compared to metal fluorides with a molecular type of structure, which indicates the manifestation of ionic-covalent type of structure. The entropy of evaporation of metal fluorides with a molecular type of structure, as well as with an ionic-covalent type, is characterized by low values (80 ÷ 140 J/mol∙K), which indicates minor changes in the structure of the molecules during evaporation. On the other hand, in the case of compounds with intermediate basicity (ZrF4, AlF3), the values of the entropy of evaporation are significantly higher (over 180 J/mol∙K), which indicates significant structural changes. A method of experimental evaluation of the volatility of compounds by measuring the rate of the coating condensation on the substrate is proposed. It is shown the possibility of combining metal fluorides into complex compounds based on the principle of basicity and on the known values of the evaporation temperature and the conventional temperature. The nature of the influence of anionic substitution in Zirconium compounds with the same charge of ions (F– → Cl– → Br– → l–) and with a change in charge (F– → O2– → N3– → C4–) on the basicity and volatility of the compounds was established. If in the first case there are no significant changes in the nature of the compounds, then in the second there is a sharp increase in melting and evaporation temperatures due to an increase in basicity.
{"title":"ACID-BASE PROPERTIES AND VOLATILIITY OF FLUORIDES OF s-, p-, d-METALS","authors":"V. Zinchenko, V. V. Menchuk, P. H. Doha","doi":"10.18524/2304-0947.2023.1(84).277055","DOIUrl":"https://doi.org/10.18524/2304-0947.2023.1(84).277055","url":null,"abstract":"A correlation between acid-base properties and volatility parameters (temperature and enthalpy of vaporization) of fluorides of s-, p-, and d-metals was revealed. As a characteristic of acid-base properties, the basicity parameter proposed in the work, based on the size-charge characteristics of the ions that make up the compound, is taken. The value of the basicity parameter naturally decreases from fluorides of low-valent metals (I–III) to fluorides of highvalent metals (IV–VII). The indicated cation substitution results in a significant increase in the volatility of compounds, which is explained by a change in the type of crystal structure from ionic-covalent to molecular one typical for acid-type fluorides. Metal fluorides with intermediate values of the basicity parameter (Zr(IV), Hf(IV), Al(III)) are characterized by significantly higher values of temperature and evaporation enthalpy, that is, lower volatility compared to metal fluorides with a molecular type of structure, which indicates the manifestation of ionic-covalent type of structure.\u0000The entropy of evaporation of metal fluorides with a molecular type of structure, as well as with an ionic-covalent type, is characterized by low values (80 ÷ 140 J/mol∙K), which indicates minor changes in the structure of the molecules during evaporation. On the other hand, in the case of compounds with intermediate basicity (ZrF4, AlF3), the values of the entropy of evaporation are significantly higher (over 180 J/mol∙K), which indicates significant structural changes. A method of experimental evaluation of the volatility of compounds by measuring the rate of the coating condensation on the substrate is proposed. It is shown the possibility of combining metal fluorides into complex compounds based on the principle of basicity and on the known values of the evaporation temperature and the conventional temperature.\u0000The nature of the influence of anionic substitution in Zirconium compounds with the same charge of ions (F– → Cl– → Br– → l–) and with a change in charge (F– → O2– → N3– → C4–) on the basicity and volatility of the compounds was established. If in the first case there are no significant changes in the nature of the compounds, then in the second there is a sharp increase in melting and evaporation temperatures due to an increase in basicity.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"109 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84765774","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 : 2023-05-10DOI: 10.18524/2304-0947.2023.1(84).277061
D. Snigur, A. Chebotarev, T. M. Shcherbakova, E. M. Rakhlytskaya, V. V. Shapovalenko
In this paper, the ionization constants (pKa) of some nitrogen-containing organic bases (monoethanolamine, diethanolamine and triethanolamine) in water-ethanol, water-acetone and water-acetonitrile solutions at various concentrations of organic solvent in the studied systems have been determined by the potentiometric titration method. It was found that the values of pKa of monoethanolamine, diethanolamine and triethanolamine in aqueous-organic solutions naturally decreases with increasing concentration of organic solvent in the system. It was shown that their nature and the physico-chemical properties of the medium are significantly influenced by the nature and degree of change in the electron donor ability of the studied nitrogen-containing organic bases. It should be noted that for the studied nitrogen-containing organic bases (monoethanolamine, diethanolamine and triethanolamine), when passing from an aqueous medium to an organic one (ethanol or acetone or acetonitrile), the pKa values naturally decrease with an increase in the content of the organic solvent in the system. In general, in the transition from an aqueous medium to an organic one (ethanol or acetone or acetonitrile), a change in pKa can reach 1.73 units. It was established that the dependence of the values of pKa of nitrogen-containing organic bases which were determinate via potentiometric titration method on the inverse of the dielectric constant of water-ethanol and water-acetone or water-acetonitrile solutions tends to be linear, consistent with Izmailov’s theory. Thus, we can conclude that the change in the ratio of the mixed solvent components and, as a result, in general, dielectric permeability of the medium does not lead to a significant change in the solvation characteristics of the studied nitrogen-containing organic bases.
{"title":"IONIZATION OF ETHANOLAMINES IN WATER- ORGANIC MEDIA","authors":"D. Snigur, A. Chebotarev, T. M. Shcherbakova, E. M. Rakhlytskaya, V. V. Shapovalenko","doi":"10.18524/2304-0947.2023.1(84).277061","DOIUrl":"https://doi.org/10.18524/2304-0947.2023.1(84).277061","url":null,"abstract":"In this paper, the ionization constants (pKa) of some nitrogen-containing organic bases (monoethanolamine, diethanolamine and triethanolamine) in water-ethanol, water-acetone and water-acetonitrile solutions at various concentrations of organic solvent in the studied systems have been determined by the potentiometric titration method. It was found that the values of pKa of monoethanolamine, diethanolamine and triethanolamine in aqueous-organic solutions naturally decreases with increasing concentration of organic solvent in the system. It was shown that their nature and the physico-chemical properties of the medium are significantly influenced by the nature and degree of change in the electron donor ability of the studied nitrogen-containing organic bases. It should be noted that for the studied nitrogen-containing organic bases (monoethanolamine, diethanolamine and triethanolamine), when passing from an aqueous medium to an organic one (ethanol or acetone or acetonitrile), the pKa values naturally decrease with an increase in the content of the organic solvent in the system. In general, in the transition from an aqueous medium to an organic one (ethanol or acetone or acetonitrile), a change in pKa can reach 1.73 units. It was established that the dependence of the values of pKa of nitrogen-containing organic bases which were determinate via potentiometric titration method on the inverse of the dielectric constant of water-ethanol and water-acetone or water-acetonitrile solutions tends to be linear, consistent with Izmailov’s theory. Thus, we can conclude that the change in the ratio of the mixed solvent components and, as a result, in general, dielectric permeability of the medium does not lead to a significant change in the solvation characteristics of the studied nitrogen-containing organic bases.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88444737","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 : 2023-05-10DOI: 10.18524/2304-0947.2023.1(84).277059
O. O. Kiose, S. M. Savin
In the present work, the kinetics of radical copolymerization in solution at the initial stages of polyglycol maleinate phthalates modified with nitrogen-containing compounds with methyl methacrylate in a ratio of 1:1 was studied. Cyclohexanone was used as a solvent, and benzoyl peroxide was used as an initiator. The study was carried out at temperatures of 50 and 60 °C by dilatometry using collapsible dilatometers and a centrifuge. 13 amine-containing compounds of different types were chosen as modifiers. Also, for comparison, the possibility of using amides and hydrazines as modifiers was checked. Polycondensation was carried out in an oil bath at 175 °C and with vigorous stirring with water withdrawal until a constant acid number was reached. It is shown that the addition of 0.1 mol/l modifier during the polycondensation of a mixture of maleic and phthalic anhydrides with ethylene glycol makes it possible to obtain an unsaturated oligoester, for which the temperature coefficient of the reaction of its copolymerization with methyl methacrylate is significantly reduced. This allows for non-isothermal curing to increase the volume of the copolymer block without the risk of overheating and destruction. Of the studied amines, para-aminoacetophenone turned out to be the most effective; its use as a modifier makes it possible to reduce the temperature coefficient of the reaction from 2.1 to 1.7. The rate of copolymerization at the initial stages for the studied modified systems decreases from 2 to 20 times. The results of the work allow us to propose a technology for the production of polymeric materials by molding them in blocks of much larger sizes than with the use of traditional unsaturated oligomers. Also, calculations were carried out according to a special technique and the maximum size of a copolymer block in the form of a cylinder was determined, in which the height is equal to the radius, which can be obtained by forming it in a non-isothermal mode in a thin layer form with convection air cooling and the maximum allowable temperature in the system is 90 °C. It is shown that the volume of such a block, when using some modified oligomers, increases significantly. Some physical and mechanical characteristics of the obtained copolymers with methyl methacrylate were determined, and it was shown that modification with nitrogen-containing compounds does not improve or worsen the studied characteristics.
{"title":"COPOLYMERIZATION OF UNSATURATED OLIGOESTERS MODIFIED WITH NITROGEN-CONTAINING COMPOUNDS WITH METHYL METHACRYLATE","authors":"O. O. Kiose, S. M. Savin","doi":"10.18524/2304-0947.2023.1(84).277059","DOIUrl":"https://doi.org/10.18524/2304-0947.2023.1(84).277059","url":null,"abstract":"In the present work, the kinetics of radical copolymerization in solution at the initial stages of polyglycol maleinate phthalates modified with nitrogen-containing compounds with methyl methacrylate in a ratio of 1:1 was studied. Cyclohexanone was used as a solvent, and benzoyl peroxide was used as an initiator. The study was carried out at temperatures of 50 and 60 °C by dilatometry using collapsible dilatometers and a centrifuge. 13 amine-containing compounds of different types were chosen as modifiers. Also, for comparison, the possibility of using amides and hydrazines as modifiers was checked. Polycondensation was carried out in an oil bath at 175 °C and with vigorous stirring with water withdrawal until a constant acid number was reached. It is shown that the addition of 0.1 mol/l modifier during the polycondensation of a mixture of maleic and phthalic anhydrides with ethylene glycol makes it possible to obtain an unsaturated oligoester, for which the temperature coefficient of the reaction of its copolymerization with methyl methacrylate is significantly reduced. This allows for non-isothermal curing to increase the volume of the copolymer block without the risk of overheating and destruction. Of the studied amines, para-aminoacetophenone turned out to be the most effective; its use as a modifier makes it possible to reduce the temperature coefficient of the reaction from 2.1 to 1.7. The rate of copolymerization at the initial stages for the studied modified systems decreases from 2 to 20 times. The results of the work allow us to propose a technology for the production of polymeric materials by molding them in blocks of much larger sizes than with the use of traditional unsaturated oligomers. Also, calculations were carried out according to a special technique and the maximum size of a copolymer block in the form of a cylinder was determined, in which the height is equal to the radius, which can be obtained by forming it in a non-isothermal mode in a thin layer form with convection air cooling and the maximum allowable temperature in the system is 90 °C. It is shown that the volume of such a block, when using some modified oligomers, increases significantly. Some physical and mechanical characteristics of the obtained copolymers with methyl methacrylate were determined, and it was shown that modification with nitrogen-containing compounds does not improve or worsen the studied characteristics.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83345807","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 : 2023-05-10DOI: 10.18524/2304-0947.2023.1(84).277069
V. Larionov, A. O. Tsisak, S. S. Bieniet
Phenolic compounds are the most numerous and the most studied group of plant biology activity compounds. Phenolic compounds participate in various metabolic processes, which cause their biological activity. All natural phenolic compounds are low toxicity and show a wide range of effects on the human body. The most promising area of applied research is the study of the antioxidant, antibacterial, cytotoxic properties of phenolic compounds in order to obtain safe drugs of natural origin for the pharmaceutical industry. The search for new sources of plant phenolic compounds can be an effective, environmentally and economically advantageous alternative to their synthetic analogues. Compounds of polyphenolic nature are almost the most numerous class of biologically active substances that exhibit a high antioxidant status and, as a result, have a wide range of pharmacotherapeutic activity. For the analysis, an alcohol-water extract of thyme herb obtained by infusing for 7 days was used. The content of flavonoids, hydroxycinnamic acids and the amount of polyphenolic compounds were determined spectrophotometrically in terms of rutin, chlorogenic acid and gallic acid, respectively. It was shown that the content of flavonoids, hydroxycinnamic acids and the sum of polyphenolic compounds in terms of rutin, chlorogenic acid and gallic acid in the investigated samples of thyme herb is 1.531, 0.505 and 5.478%, respectively. Antioxidant activity was determined in vitro. A 0.1% solution of adrenaline hydrochloride was used as a system that produces the superoxide radical, taking the autoxidation of adrenaline into adrenochrome in an alkaline environment. During the study of antioxidant activity, a sufficiently high level of it was found in the thyme herb extract, the indicators were 50% at the beginning of exposure, increased to 57,45% after 15 seconds and, gradually decreasing further, still remained sufficiently pronounced. It was calculated that the rate of the autoxidation reaction of adrenaline in the experimental sample with the addition of creeping thyme extract was 0.0310 ou/min, against the control sample – 0.0446 ou/min, where pure adrenaline was used, while the indicator of the percentage of reaction inhibition when using the tested extract was 30.33%.
{"title":"POLYPHENOLIC STATUS AND ANTIOXIDANT ACTIVITY OF THE HERB THYMUS SERPYLLUM L.","authors":"V. Larionov, A. O. Tsisak, S. S. Bieniet","doi":"10.18524/2304-0947.2023.1(84).277069","DOIUrl":"https://doi.org/10.18524/2304-0947.2023.1(84).277069","url":null,"abstract":"Phenolic compounds are the most numerous and the most studied group of plant biology activity compounds. Phenolic compounds participate in various metabolic processes, which cause their biological activity. All natural phenolic compounds are low toxicity and show a wide range of effects on the human body. The most promising area of applied research is the study of the antioxidant, antibacterial, cytotoxic properties of phenolic compounds in order to obtain safe drugs of natural origin for the pharmaceutical industry. The search for new sources of plant phenolic compounds can be an effective, environmentally and economically advantageous alternative to their synthetic analogues.\u0000Compounds of polyphenolic nature are almost the most numerous class of biologically active substances that exhibit a high antioxidant status and, as a result, have a wide range of pharmacotherapeutic activity.\u0000For the analysis, an alcohol-water extract of thyme herb obtained by infusing for 7 days was used.\u0000The content of flavonoids, hydroxycinnamic acids and the amount of polyphenolic compounds were determined spectrophotometrically in terms of rutin, chlorogenic acid and gallic acid, respectively.\u0000It was shown that the content of flavonoids, hydroxycinnamic acids and the sum of polyphenolic compounds in terms of rutin, chlorogenic acid and gallic acid in the investigated samples of thyme herb is 1.531, 0.505 and 5.478%, respectively.\u0000Antioxidant activity was determined in vitro. A 0.1% solution of adrenaline hydrochloride was used as a system that produces the superoxide radical, taking the autoxidation of adrenaline into adrenochrome in an alkaline environment.\u0000During the study of antioxidant activity, a sufficiently high level of it was found in the thyme herb extract, the indicators were 50% at the beginning of exposure, increased to 57,45% after 15 seconds and, gradually decreasing further, still remained sufficiently pronounced.\u0000It was calculated that the rate of the autoxidation reaction of adrenaline in the experimental sample with the addition of creeping thyme extract was 0.0310 ou/min, against the control sample – 0.0446 ou/min, where pure adrenaline was used, while the indicator of the percentage of reaction inhibition when using the tested extract was 30.33%.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84460119","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 : 2023-05-10DOI: 10.18524/2304-0947.2023.1(84).277057
T. Kiose, A. Nazar, L. Raskola
It is known that a large amount of sulfur dioxide is released into the atmosphere during the production of sulfuric acid, the combustion of metal sulfides at non-ferrous metallurgy enterprises, during the burning of coal containing sulfur, at thermal power plants, and in many other industries. In the air of industrial companies, its concentrations often significantly exceed the maximum allowable concentration (10 mg/m3 for the working area), despite the use of equipment for the sanitary treatment of exhaust gases. Therefore, there is a need to develop highly effective personal protection equipment of workers’ respiratory organs against sulfur dioxide in the form of respirators or gas masks. For their production, it is necessary to create cheap, affordable and reliable sorbents. A large number of methods for cleaning air and exhaust gases from sulfur dioxide are known. Among them, a special place is occupied by methods based on the use of nitrogen-containing bases, for example, urea, mono-, di- and triethanolamines, hydrazine, hydroxylamine, and hexamethylene tetramine (HMTA). Therefore, the use of aqueous solutions of nitrogen-containing bases as active components of sulfur dioxide chemosorbents is quite promising. However, their use in respiratory personal protection equipment, which would work according to the principle of using the absorption process, is quite difficult. Therefore, we made an attempt to impregnate a porous medium, as natural flagopite, with aqueous solutions of HMTA and NaOH. It was determined using X-ray phase analysis, that natural phlogopite, in addition to the main phlogopite phase, contains various impurities, such as diopside, vermiculite, clinochlore, and cordierite. To establish the type of adsorption, the adsorption and desorption of sulfur dioxide by natural phlogopite was studied. It has been proven that sulfur dioxide is weakly bound to the surface of natural phlogopite, that is, its physical adsorption mainly occurs. The perspective of using natural and chemically modified phlogopite for chemisorption neutralization of sulfur dioxide, provided its low concentration (150 mg/m3) in the air, is shown. It was established that monocomponent compositions based on NaOH and HMTA fixed on natural phlogopite absorb sulfur dioxide, but under the condition of their combined action at a certain ratio of components, a synergistic effect is observed, which is manifested in an increase in the time of the protective effect and adsorption capacity of the compositions.
{"title":"CHEMOSORPTION COMPOSITIONS BASED ON PHLOGOPITE FOR LOW-TEMPERATURE AIR PURIFICATION FROM SULFUR DIOXIDE","authors":"T. Kiose, A. Nazar, L. Raskola","doi":"10.18524/2304-0947.2023.1(84).277057","DOIUrl":"https://doi.org/10.18524/2304-0947.2023.1(84).277057","url":null,"abstract":"It is known that a large amount of sulfur dioxide is released into the atmosphere during the production of sulfuric acid, the combustion of metal sulfides at non-ferrous metallurgy enterprises, during the burning of coal containing sulfur, at thermal power plants, and in many other industries. In the air of industrial companies, its concentrations often significantly exceed the maximum allowable concentration (10 mg/m3 for the working area), despite the use of equipment for the sanitary treatment of exhaust gases. Therefore, there is a need to develop highly effective personal protection equipment of workers’ respiratory organs against sulfur dioxide in the form of respirators or gas masks. For their production, it is necessary to create cheap, affordable and reliable sorbents. A large number of methods for cleaning air and exhaust gases from sulfur dioxide are known. Among them, a special place is occupied by methods based on the use of nitrogen-containing bases, for example, urea, mono-, di- and triethanolamines, hydrazine, hydroxylamine, and hexamethylene tetramine (HMTA). Therefore, the use of aqueous solutions of nitrogen-containing bases as active components of sulfur dioxide chemosorbents is quite promising. However, their use in respiratory personal protection equipment, which would work according to the principle of using the absorption process, is quite difficult. Therefore, we made an attempt to impregnate a porous medium, as natural flagopite, with aqueous solutions of HMTA and NaOH. It was determined using X-ray phase analysis, that natural phlogopite, in addition to the main phlogopite phase, contains various impurities, such as diopside, vermiculite, clinochlore, and cordierite. To establish the type of adsorption, the adsorption and desorption of sulfur dioxide by natural phlogopite was studied. It has been proven that sulfur dioxide is weakly bound to the surface of natural phlogopite, that is, its physical adsorption mainly occurs. The perspective of using natural and chemically modified phlogopite for chemisorption neutralization of sulfur dioxide, provided its low concentration (150 mg/m3) in the air, is shown. It was established that monocomponent compositions based on NaOH and HMTA fixed on natural phlogopite absorb sulfur dioxide, but under the condition of their combined action at a certain ratio of components, a synergistic effect is observed, which is manifested in an increase in the time of the protective effect and adsorption capacity of the compositions.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"96 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75979996","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 : 2023-01-19DOI: 10.18524/2304-0947.2022.3(83).268605
I. Stoianova, V. Zinchenko, N. Chivireva, P. Doga, G. Volchak
As part of the study of the solubility of lanthanide fluorides in salt melts, a study of the EuF3-NaCl-KCl system (upper and bottom parts) was carried out. This system is of particular interest due to the fact that Europium has two oxidation states (+2 and +3), and chloride ions are weak reducing agents. The studies were carried out by chemical and nondestructive spectroscopic methods. As for the latter, solid-phase luminescence (SPL), diffusereflectance spectroscopy (DRS), and X‑ray diffraction phase analysis (XRD) were used. The total content of lanthanides in the upper and bottom parts of the samples was determined spectrophotometrically and complexonometrically, respectively, and the content of Eu2+ was determined spectrophotometrically by the weakening of the KMnO4 color using redox reactions between Eu2+–V(V) and V(IV) (the content is equivalent to Eu2+) – KMnO4. The system (upper part) LaF3-NaCl-KCl was also studied (for Lanthanum the only oxidation state is +3) for the comparison. It was shown that during the dissolution of Europium fluoride in the NaCl-KCl melt, a partial reduction of Eu3+ to Eu2+ occurs. The data of SFL, DRS and chemical analysis showed that Eu2+ is the dominant form of europium in the upper part of the sample, and the content of EuF2 found by the chemical method (2.54% wt.) is close to the sum of the contents of EuF3 and EuF2 found by quantitative XRD (2,5% wt.). At the same time, the data of chemical and X‑ray diffraction phase analysis agree satisfactorily for the LaF3-NaCl-KCl sample. It has been suggested that the EuF3 phase detected by XRD could appear because of the oxidation of europium during the storage of the sample, and, possibly, due to the effect of ionizing radiation on the system at measuring. It has been established by spectroscopic methods that both valence forms of Europium are present in the bottom part of the sample, and the chemical analysis data (namely, the found content of fluoride ions) indicate the presence of other (except of Europium fluorides) fluorine-containing phases in this part. To identify the anionic forms of Eu3+, we used the dependence of the position of the diffuse reflection bands in the DR spectra change of variousinorganic compounds of trivalent europium form the reduced electronic polarizability of the ligand anions. According to the position of the reflection bands in the spectrum of the studied sample, it was found that the dominant form of Eu(III) in the bottom part is EuOCl∙25EuF3. Thus, using a combination of various physical and chemical methods, the presence of different valence and anionic forms of Europium in the EuF3-NaCl-KCl sample was shown and the dominant forms of Eu were established in the upper and bottom parts of the studied system.
{"title":"REVEALING AND DETERMINING THE FORMS OF COMPONENTS IN THE PRODUCT OF INTERACTION OF EUROPIUM (III) FLUORIDE WITH MELT OF NaCl-KCl","authors":"I. Stoianova, V. Zinchenko, N. Chivireva, P. Doga, G. Volchak","doi":"10.18524/2304-0947.2022.3(83).268605","DOIUrl":"https://doi.org/10.18524/2304-0947.2022.3(83).268605","url":null,"abstract":"As part of the study of the solubility of lanthanide fluorides in salt melts, a study of the EuF3-NaCl-KCl system (upper and bottom parts) was carried out. This system is of particular interest due to the fact that Europium has two oxidation states (+2 and +3), and chloride ions are weak reducing agents. The studies were carried out by chemical and nondestructive spectroscopic methods. As for the latter, solid-phase luminescence (SPL), diffusereflectance spectroscopy (DRS), and X‑ray diffraction phase analysis (XRD) were used. The total content of lanthanides in the upper and bottom parts of the samples was determined spectrophotometrically and complexonometrically, respectively, and the content of Eu2+ was determined spectrophotometrically by the weakening of the KMnO4 color using redox reactions between Eu2+–V(V) and V(IV) (the content is equivalent to Eu2+) – KMnO4. The system (upper part) LaF3-NaCl-KCl was also studied (for Lanthanum the only oxidation state is +3) for the comparison.\u0000It was shown that during the dissolution of Europium fluoride in the NaCl-KCl melt, a partial reduction of Eu3+ to Eu2+ occurs.\u0000The data of SFL, DRS and chemical analysis showed that Eu2+ is the dominant form of europium in the upper part of the sample, and the content of EuF2 found by the chemical method (2.54% wt.) is close to the sum of the contents of EuF3 and EuF2 found by quantitative XRD (2,5% wt.). At the same time, the data of chemical and X‑ray diffraction phase analysis agree satisfactorily for the LaF3-NaCl-KCl sample. It has been suggested that the EuF3 phase detected by XRD could appear because of the oxidation of europium during the storage of the sample, and, possibly, due to the effect of ionizing radiation on the system at measuring.\u0000It has been established by spectroscopic methods that both valence forms of Europium are present in the bottom part of the sample, and the chemical analysis data (namely, the found content of fluoride ions) indicate the presence of other (except of Europium fluorides) fluorine-containing phases in this part. To identify the anionic forms of Eu3+, we used the dependence of the position of the diffuse reflection bands in the DR spectra change of variousinorganic compounds of trivalent europium form the reduced electronic polarizability of the ligand anions. According to the position of the reflection bands in the spectrum of the studied sample, it was found that the dominant form of Eu(III) in the bottom part is EuOCl∙25EuF3.\u0000Thus, using a combination of various physical and chemical methods, the presence of different valence and anionic forms of Europium in the EuF3-NaCl-KCl sample was shown and the dominant forms of Eu were established in the upper and bottom parts of the studied system.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"50 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73046533","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：