Z. Muldakhmetov, A. Ordabaeva, M. Meiramov, A. Gazaliev, Zhadra Shaikenova, G.K. Mukusheva, T. Zhivotova
The paper presents the results of a physicochemical analysis of coke sample from “Euromet” LLP (Karaganda, Kazakhstan), which is a carbonaceous material with high carbon content, the absence of volatiles matter and low ash content. Carbon sorbents were obtained from low-value fractions of carbonized materials of the Karaganda region coke production by the steam-gas activation. An important advantage of using screenings (coke breeze class 0-10 mm, which was crushed and fractionated to a particle size of 2-5 mm.) is the exclusion of the energy-intensive carbonization stage from the technological process, which releases a large amount of environmentally harmful substances (phenols, cresols, gaseous emissions etc.). The optimal conditions for obtaining a sorbent from low-value coke breeze are a temperature of 850 °C and an activation time of 2 hours. The physicochemical properties (ash content, bulk density, sorption capacity for iodine and methylene blue, total pore volume for water) of carbon sorbents were determined
{"title":"Obtaining carbon sorbent from “Euromet” LLP coke breeze","authors":"Z. Muldakhmetov, A. Ordabaeva, M. Meiramov, A. Gazaliev, Zhadra Shaikenova, G.K. Mukusheva, T. Zhivotova","doi":"10.31489/2022ch2/2-22-6","DOIUrl":"https://doi.org/10.31489/2022ch2/2-22-6","url":null,"abstract":"The paper presents the results of a physicochemical analysis of coke sample from “Euromet” LLP (Karaganda, Kazakhstan), which is a carbonaceous material with high carbon content, the absence of volatiles matter and low ash content. Carbon sorbents were obtained from low-value fractions of carbonized materials of the Karaganda region coke production by the steam-gas activation. An important advantage of using screenings (coke breeze class 0-10 mm, which was crushed and fractionated to a particle size of 2-5 mm.) is the exclusion of the energy-intensive carbonization stage from the technological process, which releases a large amount of environmentally harmful substances (phenols, cresols, gaseous emissions etc.). The optimal conditions for obtaining a sorbent from low-value coke breeze are a temperature of 850 °C and an activation time of 2 hours. The physicochemical properties (ash content, bulk density, sorption capacity for iodine and methylene blue, total pore volume for water) of carbon sorbents were determined","PeriodicalId":9421,"journal":{"name":"Bulletin of the Karaganda University. \"Chemistry\" series","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79038659","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 : 2022-01-01DOI: 10.31489/2022ch2/2-22-12
V. Skachkov, L. Pasechnik, I.S. Mediankina, S. Bibanaeva, N. Sabirzyanov
High-purity gallium, not worse than 6N, with the concentration of controlled impurities (except H, C, N, O) of maximum 0.00007, including, wt.%·10–8: Fe — 2, Cu — 5, Pb — 4, Mn — 1, In — 2, and Sn — 2.5 was produced by electrolysis of preliminarily purified aluminate solutions of alumina production. An improved design of electrolyzer with increased efficiency has been developed for gallium electroextraction. It was proposed to divide the casing of the advanced-efficiency electrolyzer by longitudinal partitions into two parts, each of which was divided by transverse partitions into 8 sections. The width of these sections was by one third smaller than that of available electrolyzers. The dimensions of the sections and the arrangement of elec- trodes in them were reduced by half, from 140 to 70 mm — a distance covered by gallate and zincate ions from electrolyte depth to cathodes, which decreased the duration of electrolysis. The optimal current density of 7.5 kА/m3 at the calculated density 5.8 kА/m3 was proposed, which allowed electrical energy consumption to be reduced. The polarization component of voltage on the electrolyzer was decreased by lowering the average current density achieved by three-fold enhancement of the anode surface. The technological order of seven sequential operations of metallic gallium extraction from cycling aluminate solutions is shown: 1) purification of electrolyte by an air or vapor-air mixture; 2) purification of solution by lime; 3) galvanization of cathodes and dissolution of cathode precipitate; 4) purifying electrolysis; 5) basic electrolysis with precipitation of zinc-gallium alloy; 6) cementation of gallium by aluminum gallam; 7) removal of impurities. Preliminary purification of gallate-zincate alkaline solution allows decreasing the granular aluminum consumption to the weight ratio Al : Ga = 1 : 1 during gallium cementation
{"title":"Improvement of extraction technology and electrotechnological equipment for obtaining gallium from alumina production solutions","authors":"V. Skachkov, L. Pasechnik, I.S. Mediankina, S. Bibanaeva, N. Sabirzyanov","doi":"10.31489/2022ch2/2-22-12","DOIUrl":"https://doi.org/10.31489/2022ch2/2-22-12","url":null,"abstract":"High-purity gallium, not worse than 6N, with the concentration of controlled impurities (except H, C, N, O) of maximum 0.00007, including, wt.%·10–8: Fe — 2, Cu — 5, Pb — 4, Mn — 1, In — 2, and Sn — 2.5 was produced by electrolysis of preliminarily purified aluminate solutions of alumina production. An improved design of electrolyzer with increased efficiency has been developed for gallium electroextraction. It was proposed to divide the casing of the advanced-efficiency electrolyzer by longitudinal partitions into two parts, each of which was divided by transverse partitions into 8 sections. The width of these sections was by one third smaller than that of available electrolyzers. The dimensions of the sections and the arrangement of elec- trodes in them were reduced by half, from 140 to 70 mm — a distance covered by gallate and zincate ions from electrolyte depth to cathodes, which decreased the duration of electrolysis. The optimal current density of 7.5 kА/m3 at the calculated density 5.8 kА/m3 was proposed, which allowed electrical energy consumption to be reduced. The polarization component of voltage on the electrolyzer was decreased by lowering the average current density achieved by three-fold enhancement of the anode surface. The technological order of seven sequential operations of metallic gallium extraction from cycling aluminate solutions is shown: 1) purification of electrolyte by an air or vapor-air mixture; 2) purification of solution by lime; 3) galvanization of cathodes and dissolution of cathode precipitate; 4) purifying electrolysis; 5) basic electrolysis with precipitation of zinc-gallium alloy; 6) cementation of gallium by aluminum gallam; 7) removal of impurities. Preliminary purification of gallate-zincate alkaline solution allows decreasing the granular aluminum consumption to the weight ratio Al : Ga = 1 : 1 during gallium cementation","PeriodicalId":9421,"journal":{"name":"Bulletin of the Karaganda University. \"Chemistry\" series","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84938463","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 : 2022-01-01DOI: 10.31489/2022ch4/4-22-13
L. Chekanova, V. Vaulina, Yulia B. Elchischeva, E.S. Bardina, P. T. Pavlov
A series of new ligands — N-acyl-N'-mesylhydrazines (MSH) — of the general formula RC(O)NHNHSO2CH3 has been obtained and considered as reagents for ionic flotation (IF) of non-ferrous metals (M(II). Reagents with a radical length of C6H13 and above form hardly soluble complexes with M(II) so it is possible to implement a kind of the ionic flotation techniques — “precipitate flotation”. The ranges of pH values of the most complete precipitation of cations from solutions have been determined. Precipitates of the metal complexes were isolated; their composition was confirmed by IR spectroscopy and elemental anal-ysis. The conditional values of the solubility product (SP) of the complexes [M(HL)2] were calculated. The dependence –lg SP = 11.8 + 0.61N is fulfilled for the MSH series and Cu(II) ions. The surface-active proper-ties of compounds with R > C6H13 were established. The reagents with optimal radical length for ionic flota-tion were selected. The ionic flotation of non-ferrous metals with N-nonanoyl-N'-mesylhydrazine was carried out. The up to 95–99 % recovery of metal ions, separation of copper and associated metal ions in diapason of pH 5–6.5 was shown to be possible.
{"title":"The Selection of Reagents for Ionic Flotation of Non-Ferrous Metals in the Series of N-Acyl-N'-Mezylhydrazines","authors":"L. Chekanova, V. Vaulina, Yulia B. Elchischeva, E.S. Bardina, P. T. Pavlov","doi":"10.31489/2022ch4/4-22-13","DOIUrl":"https://doi.org/10.31489/2022ch4/4-22-13","url":null,"abstract":"A series of new ligands — N-acyl-N'-mesylhydrazines (MSH) — of the general formula RC(O)NHNHSO2CH3 has been obtained and considered as reagents for ionic flotation (IF) of non-ferrous metals (M(II). Reagents with a radical length of C6H13 and above form hardly soluble complexes with M(II) so it is possible to implement a kind of the ionic flotation techniques — “precipitate flotation”. The ranges of pH values of the most complete precipitation of cations from solutions have been determined. Precipitates of the metal complexes were isolated; their composition was confirmed by IR spectroscopy and elemental anal-ysis. The conditional values of the solubility product (SP) of the complexes [M(HL)2] were calculated. The dependence –lg SP = 11.8 + 0.61N is fulfilled for the MSH series and Cu(II) ions. The surface-active proper-ties of compounds with R > C6H13 were established. The reagents with optimal radical length for ionic flota-tion were selected. The ionic flotation of non-ferrous metals with N-nonanoyl-N'-mesylhydrazine was carried out. The up to 95–99 % recovery of metal ions, separation of copper and associated metal ions in diapason of pH 5–6.5 was shown to be possible.","PeriodicalId":9421,"journal":{"name":"Bulletin of the Karaganda University. \"Chemistry\" series","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91382744","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}
I. Korolkov, A. V. Zibert, L. Lisovskaya, K. Ludzik, M. Anisovich, M. Vasilyeva, A. Shumskaya, A. Usseinov, A. B. Yeszhanov, M. Zdorovets
Neutron capture therapy is a promising method for cancer treatment based on targeted delivery of specific isotopes into cancer cells and subsequent irradiation with epithermal neutrons. As a result, a large amount of energy is released at a distance comparable to the size of the cell, destroying it from the inside. For the targeted delivery of isotopes, magnetic iron oxide nanoparticles can be used. In this article, iron oxide nanoparticles (Fe3O4) were modified with silanes and polyelectrolyte complexes for simultaneous immobilization of gadolinium ions and carborane compounds through ionic interaction for potential application in targeted delivery into cancer cells for neutron capture therapy. Structure, size and element composition was elucidated by Fourier-transform infrared spectroscopy (FTIR), Energy-dispersive X-ray spectroscopy (EDA), dynamic light scattering (DLS) and X-ray diffraction (XRD) analysis. It was found that according EDA, resulting nanoparticles consist of 15.4 % boron and 1.5 % gadolinium, with average hydrodynamical size of 386 nm measured by DLS. An in vitro cytotoxicity test using HepG2 (a cancer cell line) and human skin fibroblasts (a normal cell line) showed minor cytotoxicity in concentration range from 0.05 to 1 mg/mL.
{"title":"Simultaneous immobilization of gadolinium ions and di(o-carborano-1,2-dimethyl)borate on Fe3O4 nanoparticles","authors":"I. Korolkov, A. V. Zibert, L. Lisovskaya, K. Ludzik, M. Anisovich, M. Vasilyeva, A. Shumskaya, A. Usseinov, A. B. Yeszhanov, M. Zdorovets","doi":"10.31489/2022ch2/2-22-3","DOIUrl":"https://doi.org/10.31489/2022ch2/2-22-3","url":null,"abstract":"Neutron capture therapy is a promising method for cancer treatment based on targeted delivery of specific isotopes into cancer cells and subsequent irradiation with epithermal neutrons. As a result, a large amount of energy is released at a distance comparable to the size of the cell, destroying it from the inside. For the targeted delivery of isotopes, magnetic iron oxide nanoparticles can be used. In this article, iron oxide nanoparticles (Fe3O4) were modified with silanes and polyelectrolyte complexes for simultaneous immobilization of gadolinium ions and carborane compounds through ionic interaction for potential application in targeted delivery into cancer cells for neutron capture therapy. Structure, size and element composition was elucidated by Fourier-transform infrared spectroscopy (FTIR), Energy-dispersive X-ray spectroscopy (EDA), dynamic light scattering (DLS) and X-ray diffraction (XRD) analysis. It was found that according EDA, resulting nanoparticles consist of 15.4 % boron and 1.5 % gadolinium, with average hydrodynamical size of 386 nm measured by DLS. An in vitro cytotoxicity test using HepG2 (a cancer cell line) and human skin fibroblasts (a normal cell line) showed minor cytotoxicity in concentration range from 0.05 to 1 mg/mL.","PeriodicalId":9421,"journal":{"name":"Bulletin of the Karaganda University. \"Chemistry\" series","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87360347","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 : 2022-01-01DOI: 10.31489/2022ch4/4-22-19
S. Tyanakh, M. Baikenov, A.M. Gulmaliev, Fengyun Ma, G. Musina, T. Khamitova, A. Bolatbay
The thermal decomposition of low-temperature coal tar (LTCT) obtained from the coals of Shubarkol Komir JSC of the Republic of Qazaqstan in the presence of nanocatalysts with metal oxides (iron, cobalt and nickel) supported on microsilicate was studied for the first time. Microsilicate acts as a carrier and catalyst. Microsilicate is a product of the Karaganda silicon plant of “Tau-Ken.temir” LLP. The main chemical com-ponent of the original microsilicate is silicon oxide. The individual and chemical phase composition of the microsilicate was determined using X-ray spectral analysis. The particle size of the initial microsilicate and the mixture of microsilicate with metal oxide catalysts (nickel, cobalt, and iron) was determined using a nanosizer. Stages of thermal decomposition of LTCT and a mixture of LTCT with catalysts under conditions of programmed heating up to 640 °С in a nitrogen atmosphere have been established. On the basis of thermogravimetric analysis, the kinetic parameters (activation energy, mass loss rate, and pre-exponential fac-tor) of LTCT pyrolysis and mixture with added catalysts were determined. The modelless integral isoconversion Ozawa–Flynn–Wall method was used to determine the kinetic parameters. The values of the activation energy for the thermal destruction of the LTCT in the absence and presence of the nanocatalyst ranged from 54.04 to 297.5 kJ/mol. A kinetic compensation effect was revealed, probably due to the multi-component composition of the LTCT and the influence of added catalysts to the LTCT. The thermogravimetry method showed a high effect of the supported catalysts on the thermal degradation of LTCT. This method was used to determine the values of the activation energy and the pre-exponential degra-dation factor for the LTCT and the mixture with catalysts at different heating rates, which allows a detailed interpretation of the thermal analysis data. The obtained results of the kinetics of decomposition of LTCT can be used to create a database for mathematical modeling of the process of processing this type of raw material.
{"title":"Kinetics of Thermolysis of a Low-Temperature Tar in the Presence of a Catalyzer Agent with Deposited Metals","authors":"S. Tyanakh, M. Baikenov, A.M. Gulmaliev, Fengyun Ma, G. Musina, T. Khamitova, A. Bolatbay","doi":"10.31489/2022ch4/4-22-19","DOIUrl":"https://doi.org/10.31489/2022ch4/4-22-19","url":null,"abstract":"The thermal decomposition of low-temperature coal tar (LTCT) obtained from the coals of Shubarkol Komir JSC of the Republic of Qazaqstan in the presence of nanocatalysts with metal oxides (iron, cobalt and nickel) supported on microsilicate was studied for the first time. Microsilicate acts as a carrier and catalyst. Microsilicate is a product of the Karaganda silicon plant of “Tau-Ken.temir” LLP. The main chemical com-ponent of the original microsilicate is silicon oxide. The individual and chemical phase composition of the microsilicate was determined using X-ray spectral analysis. The particle size of the initial microsilicate and the mixture of microsilicate with metal oxide catalysts (nickel, cobalt, and iron) was determined using a nanosizer. Stages of thermal decomposition of LTCT and a mixture of LTCT with catalysts under conditions of programmed heating up to 640 °С in a nitrogen atmosphere have been established. On the basis of thermogravimetric analysis, the kinetic parameters (activation energy, mass loss rate, and pre-exponential fac-tor) of LTCT pyrolysis and mixture with added catalysts were determined. The modelless integral isoconversion Ozawa–Flynn–Wall method was used to determine the kinetic parameters. The values of the activation energy for the thermal destruction of the LTCT in the absence and presence of the nanocatalyst ranged from 54.04 to 297.5 kJ/mol. A kinetic compensation effect was revealed, probably due to the multi-component composition of the LTCT and the influence of added catalysts to the LTCT. The thermogravimetry method showed a high effect of the supported catalysts on the thermal degradation of LTCT. This method was used to determine the values of the activation energy and the pre-exponential degra-dation factor for the LTCT and the mixture with catalysts at different heating rates, which allows a detailed interpretation of the thermal analysis data. The obtained results of the kinetics of decomposition of LTCT can be used to create a database for mathematical modeling of the process of processing this type of raw material.","PeriodicalId":9421,"journal":{"name":"Bulletin of the Karaganda University. \"Chemistry\" series","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88189351","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}
A. Houbi, A. Zharmenov, Yomen Atassi, Z. Bagasharova, S. Mirzalieva, B. Karibayev
Ternary composites of polyaniline/Ni0.5Zn0.5Fe2O4/carbonyl iron (PANI/F/CI) are prepared via two stages: Firstly, Ni0.5Zn0.5Fe2O4 is prepared using a sol-gel method. After that, PANI/F/CI composites are prepared us-ing an in-situ polymerization technique of PANI in the existence of the Ni0.5Zn0.5Fe2O4 and CI. X-ray diffrac-tometry (XRD), Fourier transform infrared (FTIR) spectroscopy, Ultraviolet-visible (UV-vis) spectroscopy, and Thermogravimetric analysis (TGA) are utilized in order to characterize samples. The morphology of the powders is investigated by Scanning electron microscope (SEM). The electromagnetic interference (EMI) shielding and microwave absorption (MA) properties are measured in the frequency band of 8.8–12 GHz to investigate the microwave characterization. The results refer those microwave absorption properties are relat-ed to the absorber thickness and the loading ratio of the absorber within a paraffin matrix. Minimal reflection loss of –30.8 dB at the matching frequency (fm) of 10.3 GHz and the absorption bandwidth under –10 dB (BW–10dB) of 2.8 GHz for 3.4 mm thickness with a surface density (SD) of 3.38 kg/m2 are noticed for the PANI/F/CI composite sample. The maximum shielding efficiency (SE) of 30.12 dB at 11.0 GHz for 3.2 mm thickness is observed for the PANI/F/CI composite sample.
{"title":"Synthesis and Microwave Absorption Properties of Ni0.5Zn0.5Fe2O4/CI Composite Coated with Polyaniline within Paraffin Wax Matrix","authors":"A. Houbi, A. Zharmenov, Yomen Atassi, Z. Bagasharova, S. Mirzalieva, B. Karibayev","doi":"10.31489/2022ch3/3-22-8","DOIUrl":"https://doi.org/10.31489/2022ch3/3-22-8","url":null,"abstract":"Ternary composites of polyaniline/Ni0.5Zn0.5Fe2O4/carbonyl iron (PANI/F/CI) are prepared via two stages: Firstly, Ni0.5Zn0.5Fe2O4 is prepared using a sol-gel method. After that, PANI/F/CI composites are prepared us-ing an in-situ polymerization technique of PANI in the existence of the Ni0.5Zn0.5Fe2O4 and CI. X-ray diffrac-tometry (XRD), Fourier transform infrared (FTIR) spectroscopy, Ultraviolet-visible (UV-vis) spectroscopy, and Thermogravimetric analysis (TGA) are utilized in order to characterize samples. The morphology of the powders is investigated by Scanning electron microscope (SEM). The electromagnetic interference (EMI) shielding and microwave absorption (MA) properties are measured in the frequency band of 8.8–12 GHz to investigate the microwave characterization. The results refer those microwave absorption properties are relat-ed to the absorber thickness and the loading ratio of the absorber within a paraffin matrix. Minimal reflection loss of –30.8 dB at the matching frequency (fm) of 10.3 GHz and the absorption bandwidth under –10 dB (BW–10dB) of 2.8 GHz for 3.4 mm thickness with a surface density (SD) of 3.38 kg/m2 are noticed for the PANI/F/CI composite sample. The maximum shielding efficiency (SE) of 30.12 dB at 11.0 GHz for 3.2 mm thickness is observed for the PANI/F/CI composite sample.","PeriodicalId":9421,"journal":{"name":"Bulletin of the Karaganda University. \"Chemistry\" series","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86418224","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}
Aigerim Ayazbayeva, A. Shakhvorostov, T. Seilkhanov, V. Aseyev, S. Kudaibergenov
A novel linear amphoteric terpolymers based on neutral monomer — N-isopropylacrylamide (NIPAM), ani- onic monomer — 2-acrylamido-2-methyl-1-propanesulfonic acid sodium salt (AMPS), and cationic mono- mer — (3-acrylamidopropyl) trimethylammonium chloride (APTAC) were synthesized by free-radical polymerization in aqueous solution and characterized by methods of 1H NMR and FTIR spectroscopy, TGA, GPC, Dynamic light scattering (DLS) and zeta-potential. The thermal and salt sensitivity of amphoteric ternary polymers of various compositions, particularly, [NIPAM]:[AMPS]:[APTAC] = 90:2.5:7.5; 90:5:5; 90:7.5:2.5 mol.% were studied in aqueous and aqueous-salt solutions in the temperature range from 25 to 60 C and at the NaCl ionic strength interval from 10–3 to 1M. It was found that due to hydrophobic/hydrophilic balance, the temperature dependent conformational and phase change of macromolecular chains becomes sensitive to salt addition and allows the fine-tuning of the phase transition. In aqueous and aqueous-salt solutions, the average hydrodynamic size of amphoteric terpolymers is varied from 8 to 300 nm exhibiting bimodal distribution at room temperature. The number average (Mn) and weight average (Mw) molecular weights, polydispersity index (PDI), and zeta-potentials of amphoteric terpolymers in aqueous solu- tions were determined
{"title":"Synthesis and characterization of novel thermo- and salt-sensitive amphoteric terpolymers based on acrylamide derivatives","authors":"Aigerim Ayazbayeva, A. Shakhvorostov, T. Seilkhanov, V. Aseyev, S. Kudaibergenov","doi":"10.31489/2021ch4/9-20","DOIUrl":"https://doi.org/10.31489/2021ch4/9-20","url":null,"abstract":"A novel linear amphoteric terpolymers based on neutral monomer — N-isopropylacrylamide (NIPAM), ani- onic monomer — 2-acrylamido-2-methyl-1-propanesulfonic acid sodium salt (AMPS), and cationic mono- mer — (3-acrylamidopropyl) trimethylammonium chloride (APTAC) were synthesized by free-radical polymerization in aqueous solution and characterized by methods of 1H NMR and FTIR spectroscopy, TGA, GPC, Dynamic light scattering (DLS) and zeta-potential. The thermal and salt sensitivity of amphoteric ternary polymers of various compositions, particularly, [NIPAM]:[AMPS]:[APTAC] = 90:2.5:7.5; 90:5:5; 90:7.5:2.5 mol.% were studied in aqueous and aqueous-salt solutions in the temperature range from 25 to 60 C and at the NaCl ionic strength interval from 10–3 to 1M. It was found that due to hydrophobic/hydrophilic balance, the temperature dependent conformational and phase change of macromolecular chains becomes sensitive to salt addition and allows the fine-tuning of the phase transition. In aqueous and aqueous-salt solutions, the average hydrodynamic size of amphoteric terpolymers is varied from 8 to 300 nm exhibiting bimodal distribution at room temperature. The number average (Mn) and weight average (Mw) molecular weights, polydispersity index (PDI), and zeta-potentials of amphoteric terpolymers in aqueous solu- tions were determined","PeriodicalId":9421,"journal":{"name":"Bulletin of the Karaganda University. \"Chemistry\" series","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77904361","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 : 2021-12-30DOI: 10.31489/2021ch4/104-116
A. Abildina, Kh. Avchukir, R. Dzhumanova, A. Beiseyeva, G. Rakhymbay, A. Argimbayeva
Anode on the basis of titanium dioxide powder was made. Its morphological characteristics were investigated using ellipsometry, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). Electrochemical properties were also investigated by cyclic voltammetry. Dispersing, mixing the initial reagents for obtaining homogenized paste and its coating to a substrate, drying and cutting the electrodes were main steps of anode production. The results of ellipsometry, SEM and EDS demonstrated a uniformly distributed layer of about 200 μm thickness with porous structure, particle diameter of 50–80 nm and titanium dioxide content (45.7 %). The XRD data confirmed the active anode matrix formation with a monoclinic crystal lattice corresponding to the modification of titanium dioxide (B) with small anatase inclusions. Electrochemical behavior of the electrode was examined in acetonitrile-based Mg(TFSI)2 solution. Diffusion coefficient (DMg) and the charge transfer rate constant (kct) were determined from cyclic voltammograms 1.54∙10–2 cm2/s and 1.29∙10–4 cm/s, respectively. A two-step electrochemical reaction was revealed by the ratio of the electricity amount consumed in the cathode and anode processes at varying the number of cycles. Small values of polarization resistance (Rp) calculated from cyclic voltammograms indicated rapid diffusion of magnesium ions during intercalation/deintercalation.
{"title":"Preparation and electrochemical characterization of TiO2 as an anode material for magnesium-ion batteries","authors":"A. Abildina, Kh. Avchukir, R. Dzhumanova, A. Beiseyeva, G. Rakhymbay, A. Argimbayeva","doi":"10.31489/2021ch4/104-116","DOIUrl":"https://doi.org/10.31489/2021ch4/104-116","url":null,"abstract":"Anode on the basis of titanium dioxide powder was made. Its morphological characteristics were investigated using ellipsometry, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). Electrochemical properties were also investigated by cyclic voltammetry. Dispersing, mixing the initial reagents for obtaining homogenized paste and its coating to a substrate, drying and cutting the electrodes were main steps of anode production. The results of ellipsometry, SEM and EDS demonstrated a uniformly distributed layer of about 200 μm thickness with porous structure, particle diameter of 50–80 nm and titanium dioxide content (45.7 %). The XRD data confirmed the active anode matrix formation with a monoclinic crystal lattice corresponding to the modification of titanium dioxide (B) with small anatase inclusions. Electrochemical behavior of the electrode was examined in acetonitrile-based Mg(TFSI)2 solution. Diffusion coefficient (DMg) and the charge transfer rate constant (kct) were determined from cyclic voltammograms 1.54∙10–2 cm2/s and 1.29∙10–4 cm/s, respectively. A two-step electrochemical reaction was revealed by the ratio of the electricity amount consumed in the cathode and anode processes at varying the number of cycles. Small values of polarization resistance (Rp) calculated from cyclic voltammograms indicated rapid diffusion of magnesium ions during intercalation/deintercalation.","PeriodicalId":9421,"journal":{"name":"Bulletin of the Karaganda University. \"Chemistry\" series","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81919949","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}
The separation of rare-earth elements (REE) from a neodymium magnet has been widely studied last year. During the research it was identified that the waste of computer hard disk contains 25.41 % neodymium, 64.09 % iron, and <<1 % boron. To further isolate rare-earth metals, the magnet was acidically dissolved in open and closed systems. In both methods of dissolution, concentrated nitric acid was used. The difference between these methods is the conditions of dissolution of magnet. The magnet was dissolved in a microwave sample preparation system at different temperatures and pressures in a closed system. In the open system, the acid dissolution of the magnet is conducted at room temperature. 0.2 g of the neodymium magnet sample was taken under two conditions, and the dissolution process in the closed system lasted 1 hour, and in the open system 30-40 minutes. The open system is a non-laborious, simple, and cheap method of dissolving the magnet by comparing both systems. Therefore, an open sample preparation system is used for further work. To remove the iron in the magnet, oxalic acid was used and REEs are precipitated as oxalates under both conditions. According to the result of the Inductively coupled plasma mass spectrometry (ICP-MS) method, it was identified that the neodymium and iron contents in the precipitate are 24.66 % and 0.06 %, respectively. This shows that the iron has almost completely passed to the filtrate
{"title":"Acid dissolution of neodymium magnet Nd-Fe-B in different conditions","authors":"A. Ismailova, G.Zh. Akanova, D. Kamysbayev","doi":"10.31489/2021ch4/79-86","DOIUrl":"https://doi.org/10.31489/2021ch4/79-86","url":null,"abstract":"The separation of rare-earth elements (REE) from a neodymium magnet has been widely studied last year. During the research it was identified that the waste of computer hard disk contains 25.41 % neodymium, 64.09 % iron, and <<1 % boron. To further isolate rare-earth metals, the magnet was acidically dissolved in open and closed systems. In both methods of dissolution, concentrated nitric acid was used. The difference between these methods is the conditions of dissolution of magnet. The magnet was dissolved in a microwave sample preparation system at different temperatures and pressures in a closed system. In the open system, the acid dissolution of the magnet is conducted at room temperature. 0.2 g of the neodymium magnet sample was taken under two conditions, and the dissolution process in the closed system lasted 1 hour, and in the open system 30-40 minutes. The open system is a non-laborious, simple, and cheap method of dissolving the magnet by comparing both systems. Therefore, an open sample preparation system is used for further work. To remove the iron in the magnet, oxalic acid was used and REEs are precipitated as oxalates under both conditions. According to the result of the Inductively coupled plasma mass spectrometry (ICP-MS) method, it was identified that the neodymium and iron contents in the precipitate are 24.66 % and 0.06 %, respectively. This shows that the iron has almost completely passed to the filtrate","PeriodicalId":9421,"journal":{"name":"Bulletin of the Karaganda University. \"Chemistry\" series","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87434668","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}
This study reports for the first time about a stability indicating RP-HPLC method for analysis of darolutamide and its impurities 1, 2, and 3 in bulk and formulations. The separation was achieved on Phenomenex column with Luna C18 (250 mm × 4.6 mm, 5 μm) as stationary phase, and 50 mM ammonium acetate: methanol solution 15:80 (v/v) at pH 5.2 as mobile phase at 1.0 mL/min flow rate. UV detection was carried at wavelength of 239 nm. In these conditions the retention time of darolutamide and its impurities 1, 2, and 3 was 7.05, 8.90, 4.63 and 5.95 min, respectively. The method was validated for system suitability, range of analysis, precision, specificity, stability, and robustness. Forced degradation study was done through exposure of the analyte to five different stress conditions and the % degradation was small in all degradation condition. The proposed method can separate and estimate the drug and its impurities in pharmaceutical formulations. Hence, the developed method was suitable for the quantification of darolutamide and can separate and analyse impurities 1, 2, and 3
本研究首次建立了一种稳定性指示型RP-HPLC方法，用于分析达鲁他胺及其杂质1、2、3的原料药和制剂。采用Phenomenex色谱柱进行分离，固定相为Luna C18 (250 mm × 4.6 mm, 5 μm)，流动相为50 mm乙酸铵:甲醇溶液15:80 (v/v)， pH 5.2，流速1.0 mL/min。紫外检测波长为239 nm。在此条件下，达鲁他胺及其杂质1、2、3的保留时间分别为7.05、8.90、4.63、5.95 min。验证了该方法的系统适用性、分析范围、精密度、特异性、稳定性和鲁棒性。通过将分析物暴露于5种不同的应力条件下进行强制降解研究，在所有降解条件下，降解率都很小。所提出的方法可以分离和估计药物制剂中的药物及其杂质。因此，所建立的方法适用于达鲁他胺的定量分析，可以对杂质1、2、3进行分离分析
{"title":"Development and validation of a novel stability indicating HPLC method for the separation and determination of darolutamide and its impurities in pharmaceutical formulations","authors":"V. Kamani, M. Sujatha, G. Daddala","doi":"10.31489/2021ch4/57-68","DOIUrl":"https://doi.org/10.31489/2021ch4/57-68","url":null,"abstract":"This study reports for the first time about a stability indicating RP-HPLC method for analysis of darolutamide and its impurities 1, 2, and 3 in bulk and formulations. The separation was achieved on Phenomenex column with Luna C18 (250 mm × 4.6 mm, 5 μm) as stationary phase, and 50 mM ammonium acetate: methanol solution 15:80 (v/v) at pH 5.2 as mobile phase at 1.0 mL/min flow rate. UV detection was carried at wavelength of 239 nm. In these conditions the retention time of darolutamide and its impurities 1, 2, and 3 was 7.05, 8.90, 4.63 and 5.95 min, respectively. The method was validated for system suitability, range of analysis, precision, specificity, stability, and robustness. Forced degradation study was done through exposure of the analyte to five different stress conditions and the % degradation was small in all degradation condition. The proposed method can separate and estimate the drug and its impurities in pharmaceutical formulations. Hence, the developed method was suitable for the quantification of darolutamide and can separate and analyse impurities 1, 2, and 3","PeriodicalId":9421,"journal":{"name":"Bulletin of the Karaganda University. \"Chemistry\" series","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90839875","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}
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