Russian Journal of Applied Chemistry最新文献

{"title":"Surface Acidity Effect of Alumina in a Catalytic 1-Phenylethanol Dehydration Reaction under Excess Water","authors":"E. A. Karalin,&nbsp;G. G. Elimanova,&nbsp;I. V. Soldatov,&nbsp;A. G. Abramov,&nbsp;V. A. Vasilev,&nbsp;Kh. E. Kharlampidi,&nbsp;O. V. Zhdaneev","doi":"10.1134/S1070427224050033","DOIUrl":"10.1134/S1070427224050033","url":null,"abstract":"<p> In the propylene oxide and styrene coproduction (PO/SM) process, styrene is produced by the catalytic dehydration of 1-phenylethanol in the presence of alumina. In addition to hydrocarbon flow, direct steam is supplied to the reactor to regulate the thermal regime and reduce the rate of side reactions and the rate of catalyst deactivation. In this work, the contribution of acid sites of different natures and strengths to the activity of catalysts based on alumina in the dehydration of 1-phenylethanol, which occurs in the presence of excess water in the temperature range of 230-300°C, was assessed. A series of catalysts were prepared using the impregnation method from aqueous solutions of sodium carbonate, ammonium molybdate, ammonium metavanadate and ammonium tungstate. The acidity of the catalysts was studied using low-temperature adsorption of carbon monoxide. The dehydration reaction is not associated with Brønsted acid sites present on the surface of alumina (frequency range of CO absorption bands ν_CO = 2155-2165 cm^–1). In the presence of Lewis acid sites of varying strength on the surface of the catalyst (ν_CO = 2238–2240, 2203–2210, and 2189–2195 cm^–1) in the temperature range up to ~250°С, the contribution to the integral dehydration of the weakest Lewis acid sites (ν_CO = 2189–2195 cm^–1) did not exceed 20%. All transition metals increase the concentration of Lewis acid sites (ν_CO = 2238–2240, 2203–2210 cm^–1), which leads to an increase in the dehydration activity of catalysts toward 1-phenylethanol.</p>","PeriodicalId":757,"journal":{"name":"Russian Journal of Applied Chemistry","volume":"97 5","pages":"507 - 514"},"PeriodicalIF":0.6,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142844875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance Investigation of Electrochemical Micro Machining Process Using Salt Free Composite Electrolytes","authors":"Benjamin Lazarus Simon,&nbsp;Kumaravel Paramasivam,&nbsp;Sudhagar Manickam,&nbsp;Soundarrajan Madesh","doi":"10.1134/S107042722405001X","DOIUrl":"10.1134/S107042722405001X","url":null,"abstract":"<p>The micro holes produced using electrochemical micro machining (ECMM) process emphasis the accuracy and surface finish of micro hole due to its nature of machining. Hence, this paper attempt with different salt free electrolytes and its results are compared with normal electrolyte. The electrolyte such as sodium nitrate mixed electrolyte (SONE), copper mixed electrolyte (CUME), sulfuric acid mixed electrolyte (SFAE) and mixer of these entire materials in equal ratio considered as composite electrolyte (COME) are used for experiments. The optimization techniques such as Weighted Aggregated Sum Product Assessment (WASPAS) and Multi-Objective Optimization on the basis of Ratio Analysis (MOORA) are used to determine the best machining combination. The results obtained with experiments noted that maximum MRR, i.e., 1.8887 µm/s is obtained in COME with the parameter combination of 7 V machining voltage, 90% duty cycle and 38°C electrolyte temperature which is 98.23% higher than the SONE. Furthermore, field emission scanning electron micro scope (FESEM) image analysis and energy dispersive X-ray spectroscopy (EDX) are carried out on the micro holes to know the clarity over the effect of electrolyte on surface quality of micro hole.</p>","PeriodicalId":757,"journal":{"name":"Russian Journal of Applied Chemistry","volume":"97 5","pages":"463 - 475"},"PeriodicalIF":0.6,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142844876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structure and Properties of Hybrid Composites Based on Dressed Aluminosilicate Microspheres and Polypropylene Graft Copolymer with Methacrylic Acid","authors":"N. T. Kakhramanov,&nbsp;R. V. Kurbanova","doi":"10.1134/S1070427224050057","DOIUrl":"10.1134/S1070427224050057","url":null,"abstract":"<p>The paper presents the results of a study of the influence of the dressing process of a hollow aluminosilicate microsphere on the structural features and regulaties of changes in the main physical and mechanical characteristics of composites based on polypropylene graft copolymer with methacrylic acid. Organosilicon compound АГМ-9 (γ-aminopropyltriethoxysilane) was used as a dressing size. The mechanism of the sol-gel reaction in the process of dressing the surface of microspheres is given. The introduction of dressed microspheres into the composition of the graft copolymer made it possible to obtain hybrid composites with improved physical and mechanical properties. The most probable mechanism for the formation of the structure of hybrid composites with the formation of a three-level cross-linked spatial structure - “interpenetrating networks” is considered. The use of the method of thermomechanical studies of dressed and undressed composites confirmed the assumption of the formation of interpenetrating networks.</p>","PeriodicalId":757,"journal":{"name":"Russian Journal of Applied Chemistry","volume":"97 5","pages":"484 - 492"},"PeriodicalIF":0.6,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142844878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chitosan–Glucan Complex from Fruiting Bodies of Higher Fungi as a Base for Functional Film Hybrid Biocomposites","authors":"D. V. Chashchilov,&nbsp;D. V. Minakov,&nbsp;A. A. Minakova,&nbsp;N. V. Bychin","doi":"10.1134/S1070427224040049","DOIUrl":"10.1134/S1070427224040049","url":null,"abstract":"<p>The use of fungal raw materials for preparing various biocomposites is a promising research direction. Data on using fungal raw materials for preparing chitosan, in particular, films based on the chitosan–glucan complex, are insufficient, which determined the goal of this study. Chitin from fungal biomass, converted to chitosan by deacetylation, shows promise for preparing functional film hybrid polymer biocomposite materials. This study deals with film samples based on the chitosan–glucan complex obtained from the biomass of fruiting bodies of higher fungi. The study was aimed at preparing film materials based on the chitosan–glucan complex and at determining their structure and mechanical and physicochemical properties. The chitosan–glucan complex (CtsGC) was prepared by base hydrolysis of the chitin–glucan complex, and film materials, by wet forming onto a support. The mechanical and physicochemical properties were studied using thermogravimetric analysis, differential scanning calorimetry, and thermomechanical analysis. The film microstructure was examined using scanning electron microscopy. The forming resulted in significant texturing of the external surface relief: (1) interwoven fibrous thickenings consisting of residues of incompletely dissolved CtsGC particles are clearly seen; (2) there are closed micropores with the transverse size from 100 to 1000 nm; (3) there are local flat druses of lamellar crystals. The tensile strength of the film is up to 2.9 MPa, the elastic modulus is up 70 MPa, and the relative elongation at break is up to 14%. The water content of the film reaches 15 wt %. The product is thermally stable up to 200℃ and then gradually degrades in several steps. The results can be used for (1) preparing experimental samples of hybrid biocomposite films with various fillers, (2) assessing the possibilities of using biocomposite films, and (3) developing a future integrated technology for processing the readily renewable non-food vegetable resources into products demanded by the Russian economy.</p>","PeriodicalId":757,"journal":{"name":"Russian Journal of Applied Chemistry","volume":"97 4","pages":"414 - 421"},"PeriodicalIF":0.6,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142844734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Formation of Polymer Materials with Increased Thermal Stability","authors":"I. N. Vikhareva","doi":"10.1134/S1070427224050045","DOIUrl":"10.1134/S1070427224050045","url":null,"abstract":"<p>The paper shows the potential possibility of using vermiculite and eggshell as fillers for polymers of increased thermal stability. Formulations of PVC compositions with the content of the studied fillers have been compiled. The synergism of the effect of these additives on the thermoanalytical characteristics of PVC compositions has been studied. The joint effect on the rheology of compounds with their contents has been determined.</p>","PeriodicalId":757,"journal":{"name":"Russian Journal of Applied Chemistry","volume":"97 5","pages":"476 - 483"},"PeriodicalIF":0.6,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142844877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis and Luminescence Properties of a New Complex of Divalent Europium with Cinnamic Acid, Eu(L)2(THF)4 (L = Cinnamate Anion, С6H5СH=СHCOO–)","authors":"D. I. Galimov,&nbsp;K. S. Vasilyuk,&nbsp;S. M. Yakupova,&nbsp;R. G. Bulgakov","doi":"10.1134/S1070427224040037","DOIUrl":"10.1134/S1070427224040037","url":null,"abstract":"<p>A previously unknown luminescent complex of divalent europium, Eu(L)₂(THF)₄ (L = cinnamate anion, С₆H₅СH=СHCOO^–), was prepared by the reaction of europium(III) cinnamate crystal hydrate Eu(L)₃∙H₂O with diisobutylaluminum hydride (<i>iso-</i>C₄H₉)₂AlH in tetrahydrofuran at room temperature and atmospheric pressure. The complex Eu(L)₂(THF)₄ was isolated in the solid state and was characterized by complexometric titration (Eu²⁺) and elemental analysis (C, H, O). The yield of the complex Eu(L)₂(THF)₄ was 68%. The quantum yield of the photoluminescence (PL) of the complex (φ_PL = 0.05), the PL and PL excitation spectra, and the lifetime (τ = 377 ns) of the europium excited state, Eu²⁺*, in the complex were measured. The PL of the complex Eu(L)₂(THF)₄ is due to the interconfigurational transition 4<i>f</i>⁶5<i>d</i>¹ → 4f⁷ and is manifested as a broad diffuse band in the green part of the spectrum (λ_PL = 515 nm) with the nanosecond lifetime of the excited Eu²⁺* ions. The complex Eu(L)₂(THF)₄ exhibiting bright PL visible by naked eye can be used as a phosphor in the development of new materials with preset photophysical properties.</p>","PeriodicalId":757,"journal":{"name":"Russian Journal of Applied Chemistry","volume":"97 4","pages":"409 - 413"},"PeriodicalIF":0.6,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142844799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of the Gas Medium Composition on the Thermal Decomposition of Ammonium, Sodium, Potassium, and Calcium Hypophosphites","authors":"A. L. Vereshchagin,&nbsp;E. D. Minin,&nbsp;N. V. Bychin,&nbsp;E. A. Morozova","doi":"10.1134/S1070427224040074","DOIUrl":"10.1134/S1070427224040074","url":null,"abstract":"<p>The key step of the thermal decomposition of hypophosphites is disproportionation determining the phase composition and morphology of the final products. The distinctive features of the thermal decomposition of hypophosphites are the formation of polyphosphoric acid from ammonium hypophosphite and of red phosphorus from the metal hypophosphites. The thermal decomposition of hypophosphites in air is accompanied by large heat release.</p>","PeriodicalId":757,"journal":{"name":"Russian Journal of Applied Chemistry","volume":"97 4","pages":"395 - 401"},"PeriodicalIF":0.6,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142844729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Liquid Phase Peroxide Oxidation of Phenol in the Presence of Catalysts Based on Mixed Oxides of Transition Metals and Cellulose","authors":"A. A. Perebeinos,&nbsp;T. I. Mishchenko,&nbsp;V. V. Gurovskii,&nbsp;T. B. Medvedeva,&nbsp;D. A. Yatsenko,&nbsp;N.V. Gromov","doi":"10.1134/S1070427224050021","DOIUrl":"10.1134/S1070427224050021","url":null,"abstract":"<p>The work is devoted to the study of the process of water purification from phenol, which was oxidized in the process of liquid-phase peroxide oxidation in the presence of catalysts of composite materials based on MeFe₂O₄ (Me = Mn, Co, Mg, Cu) and cellulose. The textural and acidic properties of the catalysts were studied. It was shown that the main phase of the catalysts is MeFe₂O₄, acidity of aqueous suspensions of catalysts are neutral and slightly alkaline. Among the tested catalysts, the CuFe₂O₄/CMC (microcrystalline cellulose) sample had the greatest efficiency, in the presence of which the phenol conversion was achieved 100% for 20 min of reaction time. Copper and manganese had the greatest effectiveness as Me in the MeFe₂O₄/CMC system.</p>","PeriodicalId":757,"journal":{"name":"Russian Journal of Applied Chemistry","volume":"97 5","pages":"493 - 506"},"PeriodicalIF":0.6,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142844736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation of Novel Pyrazole Cyclic Polymer/Montmorillonite Nanocomposites and Their Thermal Decomposition Kinetics","authors":"Adnan Kurt,&nbsp;Serap Avcı,&nbsp;Murat Koca","doi":"10.1134/S107042722404013X","DOIUrl":"10.1134/S107042722404013X","url":null,"abstract":"<p>In present work, a series of novel pyrazole cyclic polymer poly(1,3-diphenyl-1<i>H</i>-pyrazol-5-yl methacrylate)/montmorillonite based nanocomposites, [poly(DPMA/OMMT : 2-7wt%) were prepared by in situ polymerization technique. Organic-modifier was vinylbenzyldimethylhexadecyl ammonium chloride. The X-ray diffraction analysis (XRD) showed that the clay dispersion in the polymer matrix was exfoliated type for all nanocomposites. A positive change was observed between the reinforced clay ratio and the thermal stability of the nanocomposites from thermogravimetry (TGA). It was determined that the nanocomposite with 7 wt % clay content was approximately 34.9°C more thermally stable than the undoped polymer. Thermal kinetic analysis of the decomposition process of nanocomposites in a conversion range of 7–19% was evaluated from dynamic experiments by means of various kinetic models such Flynn–Wall–Ozawa, Kissinger, Coats–Redfern, Tang and Madhusudanan methods. Doping the organoclay into the pyrazole polymer increased the activation energy from 79.5 to 109.5 kJ/mol compared to pure polymer. The results obtained from kinetic methods showed that all nanocomposites proceed via the thermal decomposition mechanism, <i>D</i>₁, one-dimensional diffusion type deceleration mechanism.</p>","PeriodicalId":757,"journal":{"name":"Russian Journal of Applied Chemistry","volume":"97 4","pages":"429 - 440"},"PeriodicalIF":0.6,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142844731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Kinetics of Photooxidation of Dihydric Phenols in the Presence of Hydrogen Peroxide and Potassium Persulfate","authors":"M. A. Vetrova,&nbsp;N. A. Ivantsova,&nbsp;P. R. Karataeva","doi":"10.1134/S1070427224040062","DOIUrl":"10.1134/S1070427224040062","url":null,"abstract":"<p>Wastewater treatment to remove organic ecotoxicants is one the most important problems today. Scientists’ efforts throughout the world are focused on searching for effective and harmless technologies for the removal and/or complete degradation of organic pollutants. One of the solutions is the use of UV lamps in combination with various oxidants. UV irradiation is widely used in various branches of industry, especially in water treatment. Photolysis methods are environmentally clean and are included in handbooks of the best available technologies. Experiments performed in this study were aimed at revealing kinetic relationships of the photochemical degradation of dihydric phenols in aqueous solutions under the action of active species. All the processes were performed using a flow-through laboratory installation. A 9 W, 254 nm OSMAR special ozone-free bactericidal lamp (Finland) was chosen as a UV radiation source. The residence time of the model solution in the reactor was varied from 20 to 120 s. Quantitative determination of dihydric phenols was performed by the spectrophotometric method. Hydrogen peroxide (3% solution) and potassium persulfate were chosen as oxidizing additives. The potential of the UV radiation and oxidative treatment for efficient removal of dihydric phenols from water was evaluated. Photooxidation of pyrocatechol, resorcinol, and hydroquinone in aqueous solution in the presence of hydrogen peroxide and potassium persulfate was performed. The oxidants were taken in amount from stoichiometric to fivefold excess relative to the stoichiometry. The photochemical degradation of dihydric phenols can be performed with up to 99% efficiency. At the phenol : oxidant molar ratio of 1 : 5, the photooxidation rate increases by a factor of 3–5. The degradation involves the breakdown of the benzene ring, and the main degradation products of dihydric phenols are monobasic carboxylic acids and formaldehyde.</p>","PeriodicalId":757,"journal":{"name":"Russian Journal of Applied Chemistry","volume":"97 4","pages":"441 - 447"},"PeriodicalIF":0.6,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142844733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}