Chemical Industry最新文献_第4页

Effects of temperature on physicochemical properties of the lecithin based deep eutectic solvents and their use in the CaO-catalyzed transesterification 温度对卵磷脂基深度共晶溶剂理化性质的影响及其在cao催化酯交换反应中的应用

Chemical Industry Pub Date : 2022-01-01 DOI: 10.2298/hemind220527016t

Z. Todorović, Biljana Djordevic, Dragan Z. Troter, Ljiljana Veselinović, M. Zdujić, V. Veljković

{"title":"Effects of temperature on physicochemical properties of the lecithin based deep eutectic solvents and their use in the CaO-catalyzed transesterification","authors":"Z. Todorović, Biljana Djordevic, Dragan Z. Troter, Ljiljana Veselinović, M. Zdujić, V. Veljković","doi":"10.2298/hemind220527016t","DOIUrl":"https://doi.org/10.2298/hemind220527016t","url":null,"abstract":"Deep eutectic solvents (DESs) are called 'designer solvents' due to various structural variations and the benefit of tailoring their physicochemical properties. For industrial applications of DESs it is crucial to know their physical and thermodynamic properties such as density, viscosity, and refractive index. These properties were measured for three lecithin (LEC)-based DESs with glycerol (G), triethanolamine (TEOA), and oleic acid (OLA) as functions of temperature. The viscosity was fitted by both Arrhenius-type and Vogel-Tamman-Fulcher equations. The density, viscosity, and refractive index of tested DESs decreased with the increase in temperature. The LEC:G DES exhibited the lowest density at all tested temperatures. This DES was selected as a cosolvent in the ethanolysis of cold-pressed black mustard (Brassica nigra L.) seed oil catalyzed by either calcined or non-calcined CaO. The reaction was carried out in a batch stirred reactor under the following conditions: the temperature of 70?C, the ethanol-to-oil molar ratio of 12:1, and the amount of DES and CaO of 20 and 10 wt.% (to oil), respectively. The presence of DES accelerated the reaction, while the separation of the final reaction mixture phases was faster.","PeriodicalId":9933,"journal":{"name":"Chemical Industry","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88932347","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}

引用次数: 0

Low energy nanoemulsions as carriers for essential oils in topical formulations for antioxidant skin protection 低能量纳米乳液作为抗氧化皮肤保护外用配方中精油的载体

Chemical Industry Pub Date : 2022-01-01 DOI: 10.2298/hemind210509004g

Ana Gledovic, D. Bajuk-Bogdanović, S. Uskoković-Marković, Leposava Pavun, S. Savić, Aleksandra Janošević-Ležaić

{"title":"Low energy nanoemulsions as carriers for essential oils in topical formulations for antioxidant skin protection","authors":"Ana Gledovic, D. Bajuk-Bogdanović, S. Uskoković-Marković, Leposava Pavun, S. Savić, Aleksandra Janošević-Ležaić","doi":"10.2298/hemind210509004g","DOIUrl":"https://doi.org/10.2298/hemind210509004g","url":null,"abstract":"In this study several essential oils (EOs): basil - BA, lemon balm - LB and oregano - OR were incorporated into nanoemulsions (NEs) as prospective carriers for natural and sensitive bioactives. NEs were prepared via the phase inversion composition (PIC) method, which is an energy-efficient cold process. Physicochemical stability of NEs was confirmed by particle size distribution analysis, electrical conductivity and pH value measurements, as well as by optical microscopy observations. The type of EO and the surfactant and oil mix concentration were found to be crucial factors governing the NE properties and stability. Raman spectra of the EOs confirmed main active ingredients and provided detection of interactions with the nanocarrier, which is a novel application of this technique. The antioxidant activity towards DPPH radical in methanol was concentration-dependent with a similar trend for individual oils and oil-loaded NEs (OR> LB> BA). However, the ABTS test in an aqueous medium revealed notable change in the order of activity after EO nanonisation at higher EO concentrations. Overall, it was found that OR-NE was the most effective and stable system, since OR acted as a co-stabiliser in the NE formulation, and its remarkably high antioxidant activity was successfully preserved during 6 months of storage.","PeriodicalId":9933,"journal":{"name":"Chemical Industry","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90750163","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}

引用次数: 1

Determination of silicon dioxide content in bauxite: Comparing the ICP-OES method with the UV-VIS method 铝土矿中二氧化硅含量的测定:ICP-OES法与UV-VIS法的比较

Chemical Industry Pub Date : 2022-01-01 DOI: 10.2298/hemind211223007o

G. Ostojic, D. Lazić, Saša Zeljković

{"title":"Determination of silicon dioxide content in bauxite: Comparing the ICP-OES method with the UV-VIS method","authors":"G. Ostojic, D. Lazić, Saša Zeljković","doi":"10.2298/hemind211223007o","DOIUrl":"https://doi.org/10.2298/hemind211223007o","url":null,"abstract":"In this paper, the ICP-OES method (induced coupled plasma optical emission spectrometry) was used to determine the content of silicon dioxide in bauxite, as an important impurity that affects the quality and application of bauxite in alumina production by the Bayer process. Twenty bauxite samples from seven different deposits were analysed. The results were compared with the reference spectrophotometric UV-VIS method. The mean relative difference between the silicon dioxide content determined by the ICP-OES method and the reference method is found to be 4.88 %. Statistical tests were used to assess the comparability of the two methods, followed by a scatter plot, the Bland Altman, Passing-Bablok, and the \"Mountain\" plot. Graphical comparisons generally do not show statistically significant differences between methods. The accuracy and precision of the ICP-OES method were verified by using the standard reference material SRM NIST 697, Dominican Bauxite. Recovery and repeatability values, expressed as relative standard deviation (RSD), are within the acceptance criteria. Based on the t-test, there is a statistically significant difference between the mean value of ICP-OES measurements and the certified value of silicon dioxide, which can be attributed to the effect of systematic error of ICP-OES analysis.","PeriodicalId":9933,"journal":{"name":"Chemical Industry","volume":"191 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72751877","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}

引用次数: 0

Corrigendum u clanku: Izazovi i dileme elektrohemijske konverzije i skladistenja energije, Hem. Ind. 76 (1) 43-54 (2022), https://doi.org/10.2298/HEMIND220201002D

Chemical Industry Pub Date : 2022-01-01 DOI: 10.2298/hemind220406006d

Aleksandar Dekanski

引用次数: 0

Physical simulation of finish rolling of microalloyed steels in isothermal conditions 微合金钢在等温条件下精轧机的物理模拟

Chemical Industry Pub Date : 2022-01-01 DOI: 10.2298/hemind220816018d

Stefan Dikic, D. Glišić, Abdunaser Fadel, G. Jovanović, N. Radović

{"title":"Physical simulation of finish rolling of microalloyed steels in isothermal conditions","authors":"Stefan Dikic, D. Glišić, Abdunaser Fadel, G. Jovanović, N. Radović","doi":"10.2298/hemind220816018d","DOIUrl":"https://doi.org/10.2298/hemind220816018d","url":null,"abstract":"The aim of this work was to establish a temperature of finish rolling stage of Nb/Ti microalloyed steel containing 0.06 wt.% C, 0.77 wt.% Mn, 0.039 wt.% Nb and 0.015 wt.% Ti, using physical simulation. Samples were subjected to laboratory simulation at a twist plastometer at high temperatures, i.e. between 825 and 950?C. Five pass deformation and interpass times were selected in accordance with a processing parameters at five stand finishing hot strip mill. Restoration (recovery and/or recrystallization) behavior was evaluated by calculation of Fraction Softening (FS) and Area Softening Parameter (ASP) values. At 950?C all individual pass stress-strain curves, FS and ASP show full recrystallization in all interpass intervals. On the other hand, with a decrease in temperature to the interval of 875-825?C, the extent of restoration is decreasing, leading to recovery as a sole softening mechanism at 825?C, which was confirmed by the stress-strain curve shape, and values of FS and ASP. It is assumed that, due to high supersaturation, strain-induced precipitation promoted pinning of grain and subgrain boundaries and suppressed recrystallization. Therefore, the critical temperature for finish rolling was estimated to be 825?C.","PeriodicalId":9933,"journal":{"name":"Chemical Industry","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89792047","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}

引用次数: 1

Sunflower oil methanolysis over modified CaO catalysts 改性CaO催化剂上葵花籽油的甲醇分解

Chemical Industry Pub Date : 2022-01-01 DOI: 10.2298/hemind211125009m

Marija Miladinovic, Milica Petkovic, Ivana Bankovic-Ilic, S. Konstantinović, V. Veljković

{"title":"Sunflower oil methanolysis over modified CaO catalysts","authors":"Marija Miladinovic, Milica Petkovic, Ivana Bankovic-Ilic, S. Konstantinović, V. Veljković","doi":"10.2298/hemind211125009m","DOIUrl":"https://doi.org/10.2298/hemind211125009m","url":null,"abstract":"Oil methanolysis over modified CaO catalysts was studied to assess the catalytic performance and to define an appropriate kinetic model. CaO was modified by commercial glycerol and a deep eutectic solvent (DES), choline chloride : glycerol (ChCl : Gly), to obtain catalytically active complexes of CaO and glycerol. The main goal was to investigate the effect of the obtained complexes on the reaction rate and fatty acid methyl ester (FAME) content and to describe the variation of the triacylglycerol (TAG) conversion degree during the reaction time. Fourier transform infrared spectroscopy (FTIR) was applied to confirm the formation of CaO complexes with glycerol or the glycerol-based DES. Different catalyst loadings (0.5, 1, and 5 % of oil weight) and methanol-to-oil molar ratios (6 : 1 and 12 : 1) were applied for investigation of the sunflower oil methanolysis at 60 oC. Two kinetic models were employed yielding the kinetic parameters, which depended on the catalyst loading and the methanol-to-oil molar ratio. Both models showed valid applicability for describing the kinetics of the reactions catalyzed by both complexes (the mean relative percent deviation was lower than 10 %).","PeriodicalId":9933,"journal":{"name":"Chemical Industry","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91351226","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}

引用次数: 1

Urban chemistry as a new discipline exploring chemical and chemico-biological aspects of urban environment 城市化学是一门探索城市环境化学和化学生物学方面的新兴学科

Chemical Industry Pub Date : 2022-01-01 DOI: 10.2298/hemind221204020g

E. A. Gladkov, O. Gladkova

引用次数: 0

Effects of production conditions on the properties of limestone briquettes aimed for acid soil liming 生产条件对酸性土壤石灰型煤性能的影响

Chemical Industry Pub Date : 2022-01-01 DOI: 10.2298/hemind220211011j

V. Jovanović, D. Nišić, V. Milisavljevic, D. Todorović, D. Radulovic, Branislav Ivošević, Sonja Milićević

{"title":"Effects of production conditions on the properties of limestone briquettes aimed for acid soil liming","authors":"V. Jovanović, D. Nišić, V. Milisavljevic, D. Todorović, D. Radulovic, Branislav Ivošević, Sonja Milićević","doi":"10.2298/hemind220211011j","DOIUrl":"https://doi.org/10.2298/hemind220211011j","url":null,"abstract":"This paper presents the results of experiments performed to determine how the quantity of the binder (bentonite) and the parameters of the laboratory roll press affect the quality of the briquettes obtained from limestone powder. These experiments aim to examine the conditions in which limestone briquettes are formed and to determine their use for agricultural purposes. During the experiments various mass fractions of bentonite was added to limestone (from 1 to 10 %), while the force of roll press drums ranged from 2 to 25 kN. The briquettes have been tested by applying scanning electron microscopy (SEM), differential thermal and thermo-gravimetric (DTA/TG) analyses, X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). Bentonite distribution was found to be uniform within the compact briquette structure. Formation of new compounds was not evidenced. The experiments also demonstrated that during briquetting, limestone properties remain unchanged, the changes are only physical, water solubility is not reduced, mechanical properties (impact resistance, compressive strength and abrasion resistance) are satisfactory by the transport and storage terms if the binder mass fraction is over 5% and the briquetting force exceeds 10kN and finally there is no loss due to wind dispersal during application. The only downside of the ?green? briquettes obtained is the time required for their complete disintegration if totally immersed in water.","PeriodicalId":9933,"journal":{"name":"Chemical Industry","volume":"99 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89219021","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}

引用次数: 1

Application of impregnated biocarbon produced from soybean hulls in dye decolorization 大豆皮浸渍生物炭在染料脱色中的应用

Chemical Industry Pub Date : 2021-10-01 DOI: 10.2298/hemind210427023k

Aleksandra Kulic-Mandic, M. Bečelić-Tomin, Gordana Pucar-Milidrag, M. Rašeta, Djurdja Kerkez

{"title":"Application of impregnated biocarbon produced from soybean hulls in dye decolorization","authors":"Aleksandra Kulic-Mandic, M. Bečelić-Tomin, Gordana Pucar-Milidrag, M. Rašeta, Djurdja Kerkez","doi":"10.2298/hemind210427023k","DOIUrl":"https://doi.org/10.2298/hemind210427023k","url":null,"abstract":"Waste soybean hulls (WSH) were investigated as a Fe-support in two forms: raw\u0000 and carbonized (i.e. biocarbon, BC), as possible value-added materials.\u0000 Fe-impregnation was implemented in order to produce heterogeneous Fenton\u0000 catalysts for Reactive Blue 4 dye degradation. Materials characterization\u0000 demonstrated a rise in the specific surface area due to decomposition of WSH\u0000 constituents during carbonization (to obtain BC) and thermal activation (to\u0000 obtain Fe-WSH and Fe-BC), thus producing catalysts with high mesoporosity\u0000 and hematite as the active site for Fenton reaction. Among the investigated\u0000 materials, Fe-WSH showed the greatest ability for ?OH production in acidic\u0000 medium. Next, the heterogeneous Fenton process was optimized by using\u0000 response surface methodology, which resulted in selection of the following\u0000 reaction conditions: 3 mM H2O2, 100 mg Fe-WSH, reaction time of 180 min, at\u0000 a constant pH 3, RB4 concentration of 50 mg dm-3 and at room temperature.\u0000 The achieved dye removal and mineralization were 85.7 and 66.8 %,\u0000 respectively, while the catalyst showed high stability and the reaction\u0000 intermediates formed during the oxidation process had a low inhibitory\u0000 effect on Vibrio fischeri bacteria.","PeriodicalId":9933,"journal":{"name":"Chemical Industry","volume":"64 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83419543","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}

引用次数: 1

Experimental investigation of a one-level eight-channel cyclone-separator incorporating quarter-rings 含四分之一环的一级八通道旋风分离器的实验研究

Chemical Industry Pub Date : 2021-09-02 DOI: 10.2298/hemind210307024c

A. Chlebnikovas

引用次数: 1