Pub Date : 2024-03-20DOI: 10.18412/1816-0387-2024-2-26-33
T. R. Karpova, A. V. Lavrenov, M. Moiseenko, E. A. Buluchevskii, T. Gulyaeva, A. Arbuzov
Polyfunctional Ni-containing catalysts supported on the B2O3-Al2O3 and MoO3-Al2O3 were prepared by a sequential impregnation. They were evaluated in ethylene conversion to C5+ alkenes or propylene. The catalysts were characterized by X-ray diffraction, Fourier transformed infrared spectroscopy, Fourier transformed infrared spectroscopy of adsorbed CO, UV-VIS diffuse reflectance spectroscopy, temperature programmed reduction and temperature-programmed desorption of NH3. NiO/B2O3-Al2O3 samples containing Ni2+ cations chemically bonded to the acid support are the most effective catalysts for ethylene oligomerization. The NiO/MoO3-Al2O3 catalyst activity in the ethylene conversion to propylene is related with the presence of ethylene dimerization active sites, i.e. Ni2+ cations bonded to the support acidic sites, and active sites of metathesis in the form of monomolybdate species.
通过顺序浸渍法制备了以 B2O3-Al2O3 和 MoO3-Al2O3 为载体的多官能团含镍催化剂。在乙烯转化为 C5+ 烯烃或丙烯的过程中对这些催化剂进行了评估。通过 X 射线衍射、傅立叶变换红外光谱、吸附 CO 的傅立叶变换红外光谱、紫外可见光漫反射光谱、NH3 的温度编程还原和温度编程解吸对催化剂进行了表征。含有与酸性载体化学键合的 Ni2+ 阳离子的 NiO/B2O3-Al2O3 样品是最有效的乙烯低聚催化剂。在乙烯转化为丙烯的过程中，NiO/MoO3-Al2O3 催化剂的活性与乙烯二聚化活性位点（即与载体酸性位点结合的 Ni2+ 阳离子）以及以单钼酸盐形式存在的偏聚活性位点有关。
{"title":"Nickel-containing catalysts for ethylene conversion to motor fuel components and light alkenes","authors":"T. R. Karpova, A. V. Lavrenov, M. Moiseenko, E. A. Buluchevskii, T. Gulyaeva, A. Arbuzov","doi":"10.18412/1816-0387-2024-2-26-33","DOIUrl":"https://doi.org/10.18412/1816-0387-2024-2-26-33","url":null,"abstract":"Polyfunctional Ni-containing catalysts supported on the B2O3-Al2O3 and MoO3-Al2O3 were prepared by a sequential impregnation. They were evaluated in ethylene conversion to C5+ alkenes or propylene. The catalysts were characterized by X-ray diffraction, Fourier transformed infrared spectroscopy, Fourier transformed infrared spectroscopy of adsorbed CO, UV-VIS diffuse reflectance spectroscopy, temperature programmed reduction and temperature-programmed desorption of NH3. NiO/B2O3-Al2O3 samples containing Ni2+ cations chemically bonded to the acid support are the most effective catalysts for ethylene oligomerization. The NiO/MoO3-Al2O3 catalyst activity in the ethylene conversion to propylene is related with the presence of ethylene dimerization active sites, i.e. Ni2+ cations bonded to the support acidic sites, and active sites of metathesis in the form of monomolybdate species.","PeriodicalId":17783,"journal":{"name":"Kataliz v promyshlennosti","volume":"68 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140225247","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 : 2024-03-20DOI: 10.18412/1816-0387-2024-2-34-42
I. Zubkov, O. D. Denisov, M. A. Timokhina, A. Savost’yanov, R. Yakovenko
The process of producing C5+ hydrocarbons, including unsaturated ones, on a zeolite-containing catalyst Сo-Al2O3 /SiO2 /ZSM-5/Al2O3 in flow and flow-circulation modes of operation at a temperature of 250 °C, a pressure of 2.0 MPa, GHSV 1000 h–1 has been studied , H2 /CO ratio = 1.70 in the source gas and circulation ratios of 4, 8 and 16. It was determined that the process indicators (selectivity and productivity for C5+ products) pass through a maximum at a circulation ratio of 8. The use of gas circulation in comparison with flow synthesis mode allows you to regulate the composition of products. An increase in the circulation ratio in the range of 4–16 leads to an increase in the proportion of formed olefins with a hydrocarbon chain length containing 5–20 carbon atoms, from 53.9 wt.% up to 65.7 wt.%. The use of a zeolite-containing catalyst intensifies the formation of C8–C12 alkenes in comparison with the Co-Al2O3 /SiO2 catalyst by 3,3 times – the content increases from 13,5 wt.% up to 44.2 wt.% at similar values of circulation ratio, pressure and H2 /CO ratio = 1.70 in the source gas. It was found that as the circulation ratio increases, the rate of deactivation of the zeolite-containing catalyst decreases, which may be caused by a decrease in the partial pressure of water in the reaction volume.
{"title":"Study of the influence of the gas circulation ratio on the production of C5–C18 alkenes in the Fischer–Tropsch synthesis","authors":"I. Zubkov, O. D. Denisov, M. A. Timokhina, A. Savost’yanov, R. Yakovenko","doi":"10.18412/1816-0387-2024-2-34-42","DOIUrl":"https://doi.org/10.18412/1816-0387-2024-2-34-42","url":null,"abstract":"The process of producing C5+ hydrocarbons, including unsaturated ones, on a zeolite-containing catalyst Сo-Al2O3 /SiO2 /ZSM-5/Al2O3 in flow and flow-circulation modes of operation at a temperature of 250 °C, a pressure of 2.0 MPa, GHSV 1000 h–1 has been studied , H2 /CO ratio = 1.70 in the source gas and circulation ratios of 4, 8 and 16. It was determined that the process indicators (selectivity and productivity for C5+ products) pass through a maximum at a circulation ratio of 8. The use of gas circulation in comparison with flow synthesis mode allows you to regulate the composition of products. An increase in the circulation ratio in the range of 4–16 leads to an increase in the proportion of formed olefins with a hydrocarbon chain length containing 5–20 carbon atoms, from 53.9 wt.% up to 65.7 wt.%. The use of a zeolite-containing catalyst intensifies the formation of C8–C12 alkenes in comparison with the Co-Al2O3 /SiO2 catalyst by 3,3 times – the content increases from 13,5 wt.% up to 44.2 wt.% at similar values of circulation ratio, pressure and H2 /CO ratio = 1.70 in the source gas. It was found that as the circulation ratio increases, the rate of deactivation of the zeolite-containing catalyst decreases, which may be caused by a decrease in the partial pressure of water in the reaction volume.","PeriodicalId":17783,"journal":{"name":"Kataliz v promyshlennosti","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140225313","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 : 2024-03-20DOI: 10.18412/1816-0387-2024-2-51-58
S. Zazhigalov, V. A. Shilov, A. Zagoruiko, P. Snytnikov
In this work, mathematical modeling of the autothermal reforming of hexadecane, propane and methane on catalytic blocks of different geometric shapes was carried out. It was shown that the convex shape of the block towards the oncoming reaction flow can increase the maximum temperature in the frontal zone, while the concave shape contributes to a more uniform temperature distribution along the entire length of the catalytic layer. The work also investigated the effect of the reaction flow rate on the change in the temperature gradient, which can subsequently be used to prevent the formation of hot spots and catalyst deactivation. The results obtained can serve as the basis for future research in the field of autothermal reforming and optimization of the geometric parameters of catalysts for the conversion of hydrocarbon fuels into synthesis gas.
{"title":"Variation of the shapes of catalytic blocks in the autothermal reforming of hexadecane, propane and methane using mathematical modeling","authors":"S. Zazhigalov, V. A. Shilov, A. Zagoruiko, P. Snytnikov","doi":"10.18412/1816-0387-2024-2-51-58","DOIUrl":"https://doi.org/10.18412/1816-0387-2024-2-51-58","url":null,"abstract":"In this work, mathematical modeling of the autothermal reforming of hexadecane, propane and methane on catalytic blocks of different geometric shapes was carried out. It was shown that the convex shape of the block towards the oncoming reaction flow can increase the maximum temperature in the frontal zone, while the concave shape contributes to a more uniform temperature distribution along the entire length of the catalytic layer. The work also investigated the effect of the reaction flow rate on the change in the temperature gradient, which can subsequently be used to prevent the formation of hot spots and catalyst deactivation. The results obtained can serve as the basis for future research in the field of autothermal reforming and optimization of the geometric parameters of catalysts for the conversion of hydrocarbon fuels into synthesis gas.","PeriodicalId":17783,"journal":{"name":"Kataliz v promyshlennosti","volume":"9 17","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140225405","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 : 2024-03-20DOI: 10.18412/1816-0387-2024-2-76-84
Y. V. Samoylova, K. N. Sorokina, V. N. Parmon
This article is part of a series of reviews devoted to the using microalgae biomass to obtain widely used products. In this review, microalgae are considered as a potential and renewable feedstock for producing functional materials that have found their application in the polymer industry. Strong, stable and biodegradable bioplastics from microalgae are an alternative to traditional petroleumbased plastics. The ways of obtaining bioplastics from microalgae, using the biomass directly (polyhydroxyalkanoates, starch, cellulose, organic acids), as well as using it blending with other polymers, are considered. Data are presented on the prospects of using bioplastics from microalgae, including as a result of biomass biorefinery.
{"title":"The use of microalgae biomass for the production of marketable products. Part 6: Bioplastic from microalgae","authors":"Y. V. Samoylova, K. N. Sorokina, V. N. Parmon","doi":"10.18412/1816-0387-2024-2-76-84","DOIUrl":"https://doi.org/10.18412/1816-0387-2024-2-76-84","url":null,"abstract":"This article is part of a series of reviews devoted to the using microalgae biomass to obtain widely used products. In this review, microalgae are considered as a potential and renewable feedstock for producing functional materials that have found their application in the polymer industry. Strong, stable and biodegradable bioplastics from microalgae are an alternative to traditional petroleumbased plastics. The ways of obtaining bioplastics from microalgae, using the biomass directly (polyhydroxyalkanoates, starch, cellulose, organic acids), as well as using it blending with other polymers, are considered. Data are presented on the prospects of using bioplastics from microalgae, including as a result of biomass biorefinery.","PeriodicalId":17783,"journal":{"name":"Kataliz v promyshlennosti","volume":"27 33","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140226739","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 : 2024-03-20DOI: 10.18412/1816-0387-2024-2-6-14
A. P. Bebyakina, M. I. Farid, A. Boretskaya, S. Egorova, A. Lamberov
The most common component in the design of heterogeneous catalysts for oil refining and petrochemistry are aluminum oxides. Each type of hydrocarbon raw materials and technological process corresponds to the optimal characteristics of aluminum oxide supports and catalysts: specific surface area, pore size, phase and impurity compositions. Due to the trend towards import substitution, the research of domestic producers of aluminum hydroxide used for the synthesis of aluminum oxides is becoming more relevant. In this work, domestic industrial samples of aluminum hydroxides were studied by methods of X-ray phase analysis, thermogravimetry combined with differential scanning calorimetry, low-temperature nitrogen adsorption and elemental analysis. It is established that the objects of research are most often phase-inhomogeneous, in which impurities of iron, silicon and calcium are present. The influence of the degree of crystallization and the size of the coherent scattering regions of aluminum hydroxides, mainly with the structure of boehmite and, in some cases, containing bayerite, on the textural characteristics of the resulting aluminum oxides is shown.
在炼油和石油化学的异相催化剂设计中，最常见的成分是氧化铝。每种类型的碳氢化合物原料和技术工艺都对应着氧化铝载体和催化剂的最佳特性：比表面积、孔径、相和杂质成分。由于进口替代的趋势，对国内用于合成氧化铝的氢氧化铝生产商的研究变得越来越重要。本研究采用 X 射线相分析法、热重法结合差示扫描量热法、低温氮吸附法和元素分析法对国内氢氧化铝工业样品进行了研究。研究结果表明，研究对象多为均相物，其中存在铁、硅和钙等杂质。结晶程度和铝氢氧化物相干散射区的大小（主要是波来石结构，在某些情况下含有贝叶石）对所得铝氧化物纹理特征的影响显而易见。
{"title":"Industrial aluminum hydroxides: Part 1. Phase composition and textural characteristics of industrial aluminum hydroxides/oxides","authors":"A. P. Bebyakina, M. I. Farid, A. Boretskaya, S. Egorova, A. Lamberov","doi":"10.18412/1816-0387-2024-2-6-14","DOIUrl":"https://doi.org/10.18412/1816-0387-2024-2-6-14","url":null,"abstract":"The most common component in the design of heterogeneous catalysts for oil refining and petrochemistry are aluminum oxides. Each type of hydrocarbon raw materials and technological process corresponds to the optimal characteristics of aluminum oxide supports and catalysts: specific surface area, pore size, phase and impurity compositions. Due to the trend towards import substitution, the research of domestic producers of aluminum hydroxide used for the synthesis of aluminum oxides is becoming more relevant. In this work, domestic industrial samples of aluminum hydroxides were studied by methods of X-ray phase analysis, thermogravimetry combined with differential scanning calorimetry, low-temperature nitrogen adsorption and elemental analysis. It is established that the objects of research are most often phase-inhomogeneous, in which impurities of iron, silicon and calcium are present. The influence of the degree of crystallization and the size of the coherent scattering regions of aluminum hydroxides, mainly with the structure of boehmite and, in some cases, containing bayerite, on the textural characteristics of the resulting aluminum oxides is shown.","PeriodicalId":17783,"journal":{"name":"Kataliz v promyshlennosti","volume":"27 32","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140226740","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 : 2024-03-20DOI: 10.18412/1816-0387-2024-2-59-65
K. K. Urazov, N. Sviridenko, N. S. Sergeev, A. S. Akimov, V. D. Ogorodnikov
The study deals with the products of thermal processing of heavy oil in the presence of Ni- and Co-containing catalysts that are formed in situ from the mixture of corresponding salts with ethanol. In comparison with thermal cracking, in the catalytic process the yield of bright fractions increases from 51 to 63 % and the yield of coke decreases from 3 to 2 wt.%. In the case of mixed Ni and Сo catalyst, the least yields of gas (5 wt.%) and coke (0.1 wt.%) are observed. A decrease in the sulfur content occurs in the products of both thermal (by 17 %) and catalytic cracking (from 12 to 32 rel.%) predominantly due to its removal as gaseous products. The structuralgroup characteristics of the averaged asphaltene molecules were studied before and after heavy oil cracking. XRD of solid cracking products was used to identify Ni0.96S, Ni9S8 and Co9S8 phases.
{"title":"Co and Ni-containing catalysts for heavy oil refining: the effect of ethanol on the composition and structure of catalytic cracking products","authors":"K. K. Urazov, N. Sviridenko, N. S. Sergeev, A. S. Akimov, V. D. Ogorodnikov","doi":"10.18412/1816-0387-2024-2-59-65","DOIUrl":"https://doi.org/10.18412/1816-0387-2024-2-59-65","url":null,"abstract":"The study deals with the products of thermal processing of heavy oil in the presence of Ni- and Co-containing catalysts that are formed in situ from the mixture of corresponding salts with ethanol. In comparison with thermal cracking, in the catalytic process the yield of bright fractions increases from 51 to 63 % and the yield of coke decreases from 3 to 2 wt.%. In the case of mixed Ni and Сo catalyst, the least yields of gas (5 wt.%) and coke (0.1 wt.%) are observed. A decrease in the sulfur content occurs in the products of both thermal (by 17 %) and catalytic cracking (from 12 to 32 rel.%) predominantly due to its removal as gaseous products. The structuralgroup characteristics of the averaged asphaltene molecules were studied before and after heavy oil cracking. XRD of solid cracking products was used to identify Ni0.96S, Ni9S8 and Co9S8 phases.","PeriodicalId":17783,"journal":{"name":"Kataliz v promyshlennosti","volume":"6 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140226474","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 : 2024-03-20DOI: 10.18412/1816-0387-2024-2-43-50
V. A. Shilov, S. Zazhigalov, M. A. Burmatova, A. Zagoruiko, P. Snytnikov
In this work, steam reforming and autothermal reforming of methyl oleate (a model compound of biodiesel fuel) into synthesis gas on a structured Rh-containing catalyst were investigated. It has been shown that the conversion of methyl oleate proceeds through the stage of thermal cracking followed by the conversion of the resulting organic compounds with a shorter carbon skeleton. Based on the experimental results, a mathematical model was developed that takes into account the radial temperature gradient and represents an effective tool for quantitatively describing and optimizing the biodiesel conversion process.
{"title":"Experimental studies and mathematical modeling of the catalytic conversion of biodiesel fuel into synthesis gas","authors":"V. A. Shilov, S. Zazhigalov, M. A. Burmatova, A. Zagoruiko, P. Snytnikov","doi":"10.18412/1816-0387-2024-2-43-50","DOIUrl":"https://doi.org/10.18412/1816-0387-2024-2-43-50","url":null,"abstract":"In this work, steam reforming and autothermal reforming of methyl oleate (a model compound of biodiesel fuel) into synthesis gas on a structured Rh-containing catalyst were investigated. It has been shown that the conversion of methyl oleate proceeds through the stage of thermal cracking followed by the conversion of the resulting organic compounds with a shorter carbon skeleton. Based on the experimental results, a mathematical model was developed that takes into account the radial temperature gradient and represents an effective tool for quantitatively describing and optimizing the biodiesel conversion process.","PeriodicalId":17783,"journal":{"name":"Kataliz v promyshlennosti","volume":"107 S2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140224554","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 : 2024-01-23DOI: 10.18412/1816-0387-2024-1-5-33
M. Flid
The review paper considers main regularities of the hydrogen chloride oxidation (the Deacon reaction) and oxidative chlorination of methane and ethane. The most efficient catalysts for these processes were shown to be the copper chloride systems on various supports, which contain also chlorides of alkaline and rare-earth metals that decrease the carry-over of the active phase from the catalyst surface and increase the activity. The main kinetic and technological regularities of the oxychlorination processes were considered. The conditions that promote an increase in the yield of target products – lower chloromethanes at oxychlorination of methane and vinyl chloride at oxychlorination of ethane – were revealed. Variants of technological schemes for the oxychlorination processes were proposed.
{"title":"Oxidative chlorination of hydrocarbons. Part 1. The Deacon reaction. Oxidative chlorination of saturated hydrocarbons C1 and C2","authors":"M. Flid","doi":"10.18412/1816-0387-2024-1-5-33","DOIUrl":"https://doi.org/10.18412/1816-0387-2024-1-5-33","url":null,"abstract":"The review paper considers main regularities of the hydrogen chloride oxidation (the Deacon reaction) and oxidative chlorination of methane and ethane. The most efficient catalysts for these processes were shown to be the copper chloride systems on various supports, which contain also chlorides of alkaline and rare-earth metals that decrease the carry-over of the active phase from the catalyst surface and increase the activity. The main kinetic and technological regularities of the oxychlorination processes were considered. The conditions that promote an increase in the yield of target products – lower chloromethanes at oxychlorination of methane and vinyl chloride at oxychlorination of ethane – were revealed. Variants of technological schemes for the oxychlorination processes were proposed.","PeriodicalId":17783,"journal":{"name":"Kataliz v promyshlennosti","volume":"130 29","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139605183","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 : 2024-01-23DOI: 10.18412/1816-0387-2024-1-69-82
A. V. Zaitsev, V. P. Shesterkin, E. A. Kirichenko, M. S. Kruglov
The influence of the concentration of Na+, NO2–, NO3– ions on the rate of photocatalytic oxidation of model organic dyes was studied in the article: cationic – methylene blue (MB); anionic – methyl orange (MO). Based on studies of hydrochemical indicators of polluted rivers in urban areas (Khabarovsk, Russia) in the period from 1999 to 2019, it was shown that the concentration of ions varies in the ranges: 0.005–0.7 mg/l for NO2–; 0.05–15 mg/l for NO3–; 13–180 mg/l for Na+. Optical spectrophotometry was used to study the kinetics of photooxidation of MC and MO in the concentration ranges of the studied ions: 0–1–10–100–1000–10000 mg/l using P25 titanium oxide as a photocatalyst. The photooxidation time (t) was estimated at various values of the degree of transformation (α) of dyes at: initial – 10 %t; medium – 50 %t; final – 90 %t stages of the photocatalytic process. The effect of absorption of light quanta with wavelengths of 200–350 nm by Na+/NO2– and Na+/NO3– ions is shown depending on the concentrations of these ions in the photocatalytic solution. Recommendations for practical applications of the method of photocatalytic water purification of real polluted waters are given, showing the need to take into account the concentration of the studied ions. A description of the observed effect of ions on the rate of photocatalytic oxidation of model organic dyes is proposed from the point of view of the band structure of semiconductors, elements of the theory of electrolytic dissociation and recombination of free radicals in photocatalytic processes.
{"title":"Photocatalytic oxidation of model organic dyes in the presence of Na+, NO2–, NO3– ions: theoretical and applied aspects","authors":"A. V. Zaitsev, V. P. Shesterkin, E. A. Kirichenko, M. S. Kruglov","doi":"10.18412/1816-0387-2024-1-69-82","DOIUrl":"https://doi.org/10.18412/1816-0387-2024-1-69-82","url":null,"abstract":"The influence of the concentration of Na+, NO2–, NO3– ions on the rate of photocatalytic oxidation of model organic dyes was studied in the article: cationic – methylene blue (MB); anionic – methyl orange (MO). Based on studies of hydrochemical indicators of polluted rivers in urban areas (Khabarovsk, Russia) in the period from 1999 to 2019, it was shown that the concentration of ions varies in the ranges: 0.005–0.7 mg/l for NO2–; 0.05–15 mg/l for NO3–; 13–180 mg/l for Na+. Optical spectrophotometry was used to study the kinetics of photooxidation of MC and MO in the concentration ranges of the studied ions: 0–1–10–100–1000–10000 mg/l using P25 titanium oxide as a photocatalyst. The photooxidation time (t) was estimated at various values of the degree of transformation (α) of dyes at: initial – 10 %t; medium – 50 %t; final – 90 %t stages of the photocatalytic process. The effect of absorption of light quanta with wavelengths of 200–350 nm by Na+/NO2– and Na+/NO3– ions is shown depending on the concentrations of these ions in the photocatalytic solution. Recommendations for practical applications of the method of photocatalytic water purification of real polluted waters are given, showing the need to take into account the concentration of the studied ions. A description of the observed effect of ions on the rate of photocatalytic oxidation of model organic dyes is proposed from the point of view of the band structure of semiconductors, elements of the theory of electrolytic dissociation and recombination of free radicals in photocatalytic processes.","PeriodicalId":17783,"journal":{"name":"Kataliz v promyshlennosti","volume":"118 31","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139605393","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 : 2024-01-23DOI: 10.18412/1816-0387-2024-1-60-68
V. A. Bolotov, A. E. Kibilyuk, V. N. Parmon, V. N. Panchenko, M. Timofeeva
Herein, microwave-assisted synthesis of solketal from glycerol and acetone in the presence of montmorillonite modified with aqueous solution of 0.25 mol/l HCl (0.25M HCl/MM) was demonstrated. The reaction was studied in a methanol solution at an acetone/glycerol molar ratio of 2.45–7.53, a catalyst concentration of 1.2–2.8 wt.% (based on the mass of loaded glycerol), and 30–56 °C. Solketal was shown to be the major product with 96.1–99.2 % selectivity. The maximum solketal yield of 91.3 % with 98.6 % selectivity was obtained in 15 min of the reaction at an acetone/glycerol molar ratio of 7.53, a catalyst loading of 2.3 wt.% and 56 °C. The catalytic properties of 0.25M HCl/MM in the reaction under MW heating and thermal conventional heating were compared. It was found that the yield of solketal in the MW-assisted synthesis is 2 times higher compared to the process with conventional heating.
{"title":"Microwave-assisted synthesis of solketal from glycerol and acetone","authors":"V. A. Bolotov, A. E. Kibilyuk, V. N. Parmon, V. N. Panchenko, M. Timofeeva","doi":"10.18412/1816-0387-2024-1-60-68","DOIUrl":"https://doi.org/10.18412/1816-0387-2024-1-60-68","url":null,"abstract":"Herein, microwave-assisted synthesis of solketal from glycerol and acetone in the presence of montmorillonite modified with aqueous solution of 0.25 mol/l HCl (0.25M HCl/MM) was demonstrated. The reaction was studied in a methanol solution at an acetone/glycerol molar ratio of 2.45–7.53, a catalyst concentration of 1.2–2.8 wt.% (based on the mass of loaded glycerol), and 30–56 °C. Solketal was shown to be the major product with 96.1–99.2 % selectivity. The maximum solketal yield of 91.3 % with 98.6 % selectivity was obtained in 15 min of the reaction at an acetone/glycerol molar ratio of 7.53, a catalyst loading of 2.3 wt.% and 56 °C. The catalytic properties of 0.25M HCl/MM in the reaction under MW heating and thermal conventional heating were compared. It was found that the yield of solketal in the MW-assisted synthesis is 2 times higher compared to the process with conventional heating.","PeriodicalId":17783,"journal":{"name":"Kataliz v promyshlennosti","volume":"32 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139603723","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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