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Thermal degradation of primary coal tar distillate in the presence of iron nanopowder 纳米铁粉存在下初级煤焦油馏分的热降解
IF 0.3 Pub Date : 2022-09-20 DOI: 10.15328/cb1278
Sergey Kim, M. Baikenov, D. Aitbekova, K. Ibishev, M. Meiramov, Fengyun Ma
Impact of the nanosized iron powder on the process of thermal degradation of coal tar distillate was determined by the thermogravimetric analysis. Coal tar distillate was obtained by simple distillation up to 350°C of primary coal tar from the Shubarkol deposit. Iron powder was obtained by electrochemical reduction of iron from sulfate electrolytes at simultaneous impact of high-voltage electric discharge on cathodic zone. Scanning electron microscopy showed that iron powder consists of nanosized particles (30-124 nm) forming aggregates. X-ray diffraction analysis revealed the presence of α-Fe and FeO(OH) phases. The average crystallite size determination was made using Scherrer equation and amounted to 31.7 nm. Obtained iron powder was added to the coal tar distillate in amount of 1% of distillate weight and this mixture was subjected to thermal degradation at heating rate 5°C/min in an inert atmosphere. Processing of the data obtained was carried out using the model-fitting Coats-Redfern method. The values of activation energy were calculated from the linear approximation constructed as a result of processing thermoanalytical data. It was found that the addition of iron powder in amount of 1% to the coal tar distillate reduces the activation energy from 153.98 kJ/mol to 84.48 kJ/mol.
通过热重分析测定了纳米铁粉对煤焦油馏分热降解过程的影响。通过对Shubarkol矿床的初级煤焦油进行高达350°C的简单蒸馏,获得了煤焦油馏分。在高压放电对阴极区的同时冲击下,通过电化学还原硫酸盐电解质中的铁来获得铁粉。扫描电子显微镜显示铁粉由形成聚集体的纳米颗粒(30-124nm)组成。X射线衍射分析显示存在α-Fe和FeO(OH)相。使用Scherrer方程进行平均晶粒尺寸测定,其大小为31.7nm。将获得的铁粉以馏出物重量的1%的量添加到煤焦油馏出物中,并在惰性气氛中以5°C/分钟的加热速率对该混合物进行热降解。使用模型拟合Coats-Redfern方法对所获得的数据进行处理。活化能的值是根据作为处理热分析数据的结果而构建的线性近似来计算的。研究发现,在煤焦油馏分中加入1%的铁粉,活化能从153.98kJ/mol降低到84.48kJ/mol。
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引用次数: 0
Evaluation of the effectiveness of commercial demulsifiers based on polyoxyalkylated compounds in relation to oil and water emulsions of the Sarybulak oilfield 基于聚氧化烷基化合物的商业破乳剂对Sarybulak油田油水乳液的有效性评价
IF 0.3 Pub Date : 2022-09-20 DOI: 10.15328/cb1282
A. Adilbekova, Saidulla Faizullayev, W. Kujawski
Water and oil emulsion formation is a natural process that takes place during oil recovery and processing. Heavy oils of Kazakhstan form highly stable oil emulsions mostly stabilized by a high content of asphaltenes, resins, and other surface-active components. Oil-in-water emulsions initiate the corrosion of equipment and cause transportation issues. Dewatering of oil emulsions is economically reasonable and requires universal techniques which could be applied to any sort of oil. In this study, the chemical composition of crude oil from the Sarybulak oilfield was determined, and commercial demulsifiers of Basorol brand were applied to these water-in-oil emulsions. The natural stabilizers content (asphaltenes and resins) was determined and correlated with IR-spectrum data. Finally, the effectiveness of demulsifiers is compared and explained according to their structures. It has been found that the higher the relative solubility number of the demulsifier, the better water-in-oil emulsion separation efficiency and dewatering mechanism was assumed. Results of water separation showed that Basorol PE-10400 and PE-10500 are the most effective, with DE of 96% and 91%, respectively, for 30% (vol.) water-in-oil emulsion at 60°C during 1-hour treatment.
水和油乳液的形成是在石油开采和加工过程中发生的一个自然过程。哈萨克斯坦的重油形成高度稳定的油乳液,主要由高含量的沥青质、树脂和其他表面活性成分稳定。水包油乳液会引发设备腐蚀并导致运输问题。油乳液的脱水在经济上是合理的,并且需要适用于任何类型油的通用技术。本研究测定了Sarybulak油田原油的化学成分,并将Basorol牌商业破乳剂应用于这些油包水乳液中。测定了天然稳定剂(沥青质和树脂)的含量,并将其与红外光谱数据相关联。最后,根据不同的破乳剂的结构,对其效果进行了比较和说明。研究发现,破乳剂的相对溶解度越高,则认为油包水乳液的分离效率和脱水机理越好。水分离结果表明,Basorol PE-10400和PE-10500是最有效的,在60°C下处理1小时时,对30%(体积)油包水乳液的DE分别为96%和91%。
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引用次数: 0
Synthesis, structure and features of formation of biphasic hybrid polymer compositions based on bentonite 基于膨润土的双相杂化聚合物组合物的合成、结构及形成特征
IF 0.3 Pub Date : 2022-09-20 DOI: 10.15328/cb1280
G. Mamytbekov, E. Zhakanbaev, Ernat Nurtazin, Victor Glushenko
The synthesis, structure and features of the formation of biphasic hybrid polymer compositions based on natural ionite (bentonite – BT), its intercalated complex (ICC) with a solid solution of copper ferrocyanide K4-хCux[Fe(CN)6] and a synthetic rare cross-linked acrylamide-acrylic acid copolymer were studied. The mechanism of formation of biphasic intercalated and percolated structures was analyzed by means of X-ray diffraction, X-ray fluorescence analysis, IR-Fourier spectroscopy and stress-strain curves. It is shown that the impregnation of the mineral bentonite filler into the polymer matrix, including its intercalated complex {BT:K4-xCux[Fe(CN)6]} is accompanied by an increase of non-uniformity of the structure of the hybrid composite material. It has been established that the main factor characterizing the deformation stability of the composite is the adhesive strength at the interface between the mineral filler and the polymer matrix. Under uniaxial tension of the P[AA-AA]{BT} composition and the percolated complex P[AA-AA]{BT:K4-xCux[Fe(CN)6]} their internal structure is rearranged resulting in stretching of agglomerates of solid fillers along polymer chains, which is determined by the adhesion force between polymer chains and mineral particles at the phase boundary. It is proposed to consider such biphasic hybrid composite materials as a promising class of interpenetrating networks with valuable applied properties.
研究了天然离子土(膨润土- BT)及其与亚铁氰化铜(K4-хCux[Fe(CN)6])固溶体的插层配合物(ICC)和合成的稀有交联丙烯酰胺-丙烯酸共聚物的合成、结构和形成特点。通过x射线衍射、x射线荧光分析、红外傅立叶光谱和应力-应变曲线分析了双相插层和渗透结构的形成机理。结果表明:矿物膨润土填料及其插层配合物{BT:K4-xCux[Fe(CN)6]}在聚合物基体中的浸渍,使杂化复合材料的结构不均匀性增加。确定了表征复合材料变形稳定性的主要因素是矿物填料与聚合物基体界面处的粘接强度。在P[AA-AA]{BT}组合物和P[AA-AA]{BT:K4-xCux[Fe(CN)6]}的单轴拉伸作用下,它们的内部结构发生重排,导致固体填料团块沿聚合物链伸展,这是由聚合物链与矿物颗粒在相界处的粘附力决定的。认为这种双相杂化复合材料是一种具有应用价值的互穿网络材料。
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引用次数: 0
Effect of the interaction of components in a nickel-molybdenum catalyst on its activity in decomposition of methane to hydrogen 镍钼催化剂组分相互作用对甲烷分解制氢活性的影响
IF 0.3 Pub Date : 2022-09-20 DOI: 10.15328/cb1281
N. Makayeva, G. Yergaziyeva, Moldir Anisova, Z. Shaimerden, K. Dossumov
This work is devoted to the study of the activity of monometallic (Fe/Al2O3) and bimetallic (Fe-Mo/Al2O3) catalysts supported to carrier γ- Al2O3. It has been discovered that the bimetallic catalyst is more active than the monometallic catalyst in the methane decomposition reaction. The results of the influence of molybdenum oxide on the activity of Fe/Al2O3 catalyst in the methane decomposition reaction in the temperature range 500-850°C have been obtained. It has been determined that the addition of molybdenum oxide in the amount of 5 wt. % of the iron catalyst composition leads to an increase in the catalytic activity of the sample in the reaction of methanedecomposition to hydrogen at relatively low temperatures. Compared to Fe/Al2O3 on the FeMo/Al2O3 catalyst at a reaction temperature of 750°C, methane conversionincreases from 8% to 98%, hydrogen yield from 5% to 57%.The increased field of activity Fe-Mo/Al2O3catalyst in the decomposition of methane to hydrogen compared to Fe/Al2O3 catalysts is due to an increase in the dispersity of the active phases of the catalyst, as well as the formation of an easily reduced Fe2(MоО4)3 phase, according to XRD, TPR-H2, and BET methods.
本工作致力于研究载体γ-Al2O3负载的单金属(Fe/Al2O3)和双金属(Fe-Mo/Al2O3)催化剂的活性。已经发现在甲烷分解反应中双金属催化剂比单金属催化剂更具活性。在500~850°C的温度范围内,研究了氧化钼对Fe/Al2O3催化剂在甲烷分解反应中活性的影响。已经确定,以铁催化剂组合物的5wt.%的量添加氧化钼导致样品在相对较低的温度下甲烷化组合物与氢气反应中的催化活性增加。在750°C的反应温度下,与FeMo/Al2O3催化剂上的Fe/Al2O3相比,甲烷转化率从8%提高到98%,氢气产率从5%提高到57%。根据XRD、TPR-H2和BET方法,与Fe/Al2O3催化剂相比,Fe-Mo/Al2O3催化剂在甲烷分解为氢气方面的活性场增加是由于催化剂活性相的分散性增加,以及容易还原的Fe2(MО4)3相的形成。
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引用次数: 0
Removal of Diclofenac-Na from aqueous solution onto H3PO4 modified composite clay H3PO4改性复合粘土去除水中双氯芬酸钠
IF 0.3 Pub Date : 2022-09-20 DOI: 10.15328/cb1274
A. Ajani, Ademola Toheeb Adeniji, Samson Shina Ayodabo, A. Alade, T. Afolabi, S. O. Ganiyu
Under batch experiment conditions, this work seeks to successfully remove Diclofenac-Na (DCF-Na) from an aqueous solution utilizing a composite sorbent made of Bentonite, Kaolinite clay, and Worm casting (BKW). This study investigated the structural modification of the H3PO4 Modified Clay by X-ray fluorescence and the effect of selected adsorption factors – DCF-Na concentration and modified BKW composite dosage. The concentration equilibrium data was used to study six isotherm models. Freundlich isotherm model better explained the adsorption of DCF-Na onto modified BKW composite with a correlation coefficient close to 1. Kinetics models were examined, and the Elovich model gave a better fit than other kinetic models studied. Mass diffusion mechanisms and thermodynamics studies were successfully carried out. The enthalpy change values evaluated were negative, which revealed the spontaneity of DCF-Na remediation onto modified BKW, and that DCF-Na adsorption is exothermic and occurred through a physisorption process.
在分批实验条件下,本工作试图利用膨润土、高岭土和蠕虫铸件(BKW)制成的复合吸附剂成功地从水溶液中去除双氯芬酸钠(DCF-Na)。本研究通过X射线荧光法研究了H3PO4改性粘土的结构改性,以及所选吸附因子——DCF-Na浓度和改性BKW复合剂量的影响。浓度平衡数据被用于研究六个等温线模型。Freundlich等温线模型较好地解释了DCF-Na在改性BKW复合材料上的吸附,相关系数接近1。对动力学模型进行了检验,Elovich模型比所研究的其他动力学模型拟合得更好。成功地进行了质量扩散机理和热力学研究。评估的焓变值为负值,这表明DCF-Na修复改性BKW的自发性,并且DCF-Na吸附是放热的,通过物理吸附过程发生。
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引用次数: 0
Ophthalmic drug delivery system based on the complex of gellan and ofloxacin 以结冷胶与氧氟沙星配合物为基础的眼科给药系统
IF 0.3 Pub Date : 2022-06-20 DOI: 10.15328/cb1239
G. Tatykhanova, V. Aseyev, M. Vamvakaki, V. Khutoryanskiy, S. Kudaibergenov
Complex formation between a natural polysaccharide – gellan and an antimicrobial drug – ofloxacin was studied in aqueous solution. Conductimetric and potentiometric titration curves revealed that gellan and ofloxacin forms a water-soluble complex of composition 2:1 mol/mol stabilized by ionic and hydrogen bonds. The formation of the gellan-ofloxacin complex was confirmed by FTIR spectroscopy, dynamic light scattering, zeta-potential and thermogravimetric analysis. The average hydrodynamic size of the complex was found 307±5 nm and its zeta-potential was negative and equal to -15 mV. Thin films of the gellan-ofloxacin complex, gelled in 0.3 wt.% of CaCl2, were used to study the release kinetics of ofloxacin in distilled water and phosphate buffer. The drug release kinetics evaluated by UV-Vis spectroscopy at λmax = 289 nm and calculated by the Ritger-Peppas model correspond to non-Fickian diffusion in distilled water and Case II transport (zero-order kinetics) in phosphate buffer. The cumulative release of ofloxacin from the gellan-ofloxacin films was equal to 96±2% and 36±2% in phosphate buffer and distilled water, respectively. It is expected that the gellan-ofloxacin complex is able to form in situ gel on the surface of the eye and to prolong the drug residence time in the tear fluid.
研究了天然多糖结冷胶与抗菌药物氧氟沙星在水溶液中形成的络合物。电导和电位滴定曲线表明,结冷胶与氧氟沙星形成了一种由离子键和氢键稳定的水溶性络合物,其组成为2:1 mol/mol。通过红外光谱、动态光散射、ζ电位和热重分析证实了胶凝-氧氟沙星配合物的形成。配合物的平均水动力尺寸为307±5 nm, ζ电位为负,为-15 mV。用0.3 wt.%的CaCl2凝胶化的凝胶-氧氟沙星配合物薄膜,研究了氧氟沙星在蒸馏水和磷酸盐缓冲液中的释放动力学。在λmax = 289 nm处用紫外可见光谱评价药物释放动力学,用Ritger-Peppas模型计算药物释放动力学符合蒸馏水中的非菲克扩散和磷酸盐缓冲液中的Case II转运(零级动力学)。凝胶-氧氟沙星膜在磷酸盐缓冲液和蒸馏水中的累积释放量分别为96±2%和36±2%。预计胶凝-氧氟沙星复合物能够在眼表面形成原位凝胶,并延长药物在泪液中的停留时间。
{"title":"Ophthalmic drug delivery system based on the complex of gellan and ofloxacin","authors":"G. Tatykhanova, V. Aseyev, M. Vamvakaki, V. Khutoryanskiy, S. Kudaibergenov","doi":"10.15328/cb1239","DOIUrl":"https://doi.org/10.15328/cb1239","url":null,"abstract":"Complex formation between a natural polysaccharide – gellan and an antimicrobial drug – ofloxacin was studied in aqueous solution. Conductimetric and potentiometric titration curves revealed that gellan and ofloxacin forms a water-soluble complex of composition 2:1 mol/mol stabilized by ionic and hydrogen bonds. The formation of the gellan-ofloxacin complex was confirmed by FTIR spectroscopy, dynamic light scattering, zeta-potential and thermogravimetric analysis. The average hydrodynamic size of the complex was found 307±5 nm and its zeta-potential was negative and equal to -15 mV. Thin films of the gellan-ofloxacin complex, gelled in 0.3 wt.% of CaCl2, were used to study the release kinetics of ofloxacin in distilled water and phosphate buffer. The drug release kinetics evaluated by UV-Vis spectroscopy at λmax = 289 nm and calculated by the Ritger-Peppas model correspond to non-Fickian diffusion in distilled water and Case II transport (zero-order kinetics) in phosphate buffer. The cumulative release of ofloxacin from the gellan-ofloxacin films was equal to 96±2% and 36±2% in phosphate buffer and distilled water, respectively. It is expected that the gellan-ofloxacin complex is able to form in situ gel on the surface of the eye and to prolong the drug residence time in the tear fluid.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44048683","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
Kinetic parameters of thermal destruction of the copolymer of polyethylene glycol fumarate with acrylic acid in inert medium 聚乙二醇-富马酸酯-丙烯酸共聚物在惰性介质中的热破坏动力学参数
IF 0.3 Pub Date : 2022-06-20 DOI: 10.15328/cb1260
M. Burkeev, A. Bolatbay, D. Havlícek, Y. Tazhbayev, S. Davrenbekov, L. Zhaparova
Thermal decomposition of the copolymer of polyethylene glycol fumarate with acrylic acid (p-EGF:AA) of two different compositions synthesized earlier was studied in the present work. TG and DTG curves prove that decomposition takes place in several stages. According to thermogravimetric curves it has been found out that for the copolymer with higher content of acrylic acid the decomposition of the copolymer’s sample is started at higher temperatures. It has been shown the shift of the temperature of decomposition’s start to the higher area with the increase of heating rate which is necessary for the detorsion of macromolecular coil. Experimental data processed using graphical methods of Kissinger–Akahira–Sunose and Friedman allowed us to calculate the activation energy of the thermal decomposition process. It has been established that the copolymer with the composition of 21.03:78.97 mass.% has lower meaning of activation energy than the one with the composition of 68.96:31.04 mass.%. As a result of calculation one can see that the meanings found out using these methods depend slightly on conversion. Using Achar-Brindley-Sharp method and the method of invariant kinetic parameters the kinetic triplet of the decomposition process has been found which was used to build the calculated curve. The dependences of g(α) on α using these parameters showed a satisfactory agreement of calculated curves with the experimental ones. One can conclude that the decomposition process of the copolymer of polyethylene glycol fumarate with acrylic acid is well described with of D3 (three-dimensional diffusion) model.
研究了合成的两种不同组分的富马酸聚乙二醇与丙烯酸共聚物(p-EGF:AA)的热分解反应。TG和DTG曲线证明分解分几个阶段进行。根据热重曲线,已经发现对于具有较高丙烯酸含量的共聚物,共聚物样品的分解在较高温度下开始。研究表明,随着加热速率的增加,分解起始温度向较高区域移动,这是大分子线圈还原所必需的。使用Kissinger–Akahira–Sunose和Friedman的图解方法处理的实验数据使我们能够计算热分解过程的活化能。已经确定,组成为21.03:78.97质量%的共聚物比组成为68.96:31.04质量%的聚合物具有更低的活化能含义。计算结果表明,使用这些方法得出的含义略微取决于转化率。利用Achar-Brindley-Sharp方法和动力学参数不变方法,得到了分解过程的动力学三重态,并用它建立了计算曲线。使用这些参数的g(α)与α的依赖关系表明,计算曲线与实验曲线吻合良好。可以得出结论,用D3(三维扩散)模型很好地描述了富马酸聚乙二醇与丙烯酸共聚物的分解过程。
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引用次数: 0
Synthesis of 1-propargyl-1-(2-methyl-3-oxo-3-(p-tolyl)propyl)-piperidin-1-ium bromide and its plant growth-stimulating activity assessment 1-丙炔-1-(2-甲基-3-氧-3-(对甲基)丙基)-胡椒碱-1-溴化ium的合成及其植物促生长活性评价
IF 0.3 Pub Date : 2022-06-20 DOI: 10.15328/cb1259
Y. Belyankova, A. Dauletbakov, B. Anapiyayev, A. Ten, M. Aydemir, A. Zazybin
The aim of this study was to synthesize novel ionic compound – 1-propargyl-1-(2-methyl-3-oxo-3-(p-tolyl)propyl)-piperidin-1-ium bromide – via the N-alkylation (in conventional conditions and using ultrasound activation), and investigate its influence on the plant growth-stimulating activity using of sweet sorghum seeds. The synthesized compound was fully characterized by infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy. Regardless of the type of synthesis’ methods, the isolated yield of the produced ionic compound is showed 79-81%, however, the reaction rate was significantly increased by using ultrasonic activation. For the assessment of the growth-stimulating activity of the synthesized ionic compound, parameters such as root length, shoot length, seed energy germination rate, and germination capacity were determined on 10 genotypes of sweet sorghum seeds. The results of samples with low concentration (0.001% vol. solution) were demonstrated the higher intensity for tested genotypes than control samples, especially for process of gemmogenesis and intensity of rhizogenesis. The results of this study can be used as basis for the further development of plant growth stimulants based on ionic compounds.
本研究以甜高粱种子为原料,在常规条件和超声活化下,通过n-烷基化反应合成了新型离子化合物-1-丙炔-1-(2-甲基-3-氧-3-(对甲基)丙基)-胡椒碱-1-溴化ium -,并研究了其对植物促生长活性的影响。通过红外光谱和核磁共振光谱对合成的化合物进行了表征。无论何种合成方法,所制备的离子化合物的分离率均为79-81%,而采用超声活化的反应速率明显提高。为了评价所合成的离子化合物的促生长活性,对10个基因型甜高粱种子进行了根长、茎长、种子能量发芽率和发芽量等参数的测定。结果表明,低浓度(0.001%溶液体积)样品的基因型强度高于对照样品,特别是在胚发生过程和根发生强度方面。本研究结果可为进一步开发基于离子化合物的植物生长刺激剂提供依据。
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引用次数: 0
Effect of food processing method on heavy metals 食品加工方法对重金属的影响
IF 0.3 Pub Date : 2022-06-20 DOI: 10.15328/cb1247
Alan Diyarov, N. Nursapina, I. Matveyeva, O. Ponomarenko
The problem of high content of heavy metals in food has spread broadly over the world. The presented study suggests the minimization of heavy metal content in processed food due to different applied techniques such as the frying, boiling, steaming and sous-vide. Three main food products were chosen for investigation – Daucus carota subsp. Sativus (carrot), Solanum tuberosum (potato) and Allium cepa (onion). The concentration of heavy metals (Zn, Pb, Mn, Cd, Cu) was determined in samples investigated by atomic-absorption spectrometer. The health risk index (HRI) was calculated based on obtained data. In all investigated samples, high concentration of lead was identified among the heavy metals. The highest concentration of zinc, lead and manganese was determined in boiled Daucus carota subsp. Sativus, cadmium – in sous - vide Daucus carota subsp. Sativus, copper – in steamed Daucus carota subsp. Sativus. HRI values of cadmium for Solanum tuberosum samples were ranged from 6.8 to 7.1 and for lead are ranged between 3.4 and 4.9.
食品中重金属含量高的问题已在世界各地广泛存在。本研究表明,由于不同的应用技术,如油炸、煮沸、蒸和真空,加工食品中的重金属含量应降至最低。选择了三种主要的食品进行调查——胡萝卜豆亚种。Sativus(胡萝卜)、Solanum tuberosum(土豆)和Allium cepa(洋葱)。用原子吸收光谱法测定了样品中重金属(Zn、Pb、Mn、Cd、Cu)的含量。健康风险指数(HRI)是根据获得的数据计算的。在所有调查的样品中,重金属中都发现了高浓度的铅。测定了水煮胡萝卜中锌、铅和锰的最高浓度。Sativus,镉-在胡萝卜亚种中。Sativus,铜-在蒸胡萝卜亚种中。Sativus。茄样品中镉的HRI值在6.8到7.1之间,铅的HRI在3.4到4.9之间。
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引用次数: 0
The use of natural zeolite and chamotte clay-based sorbents for the extraction of sodium and potassium ions from saline water: a preliminary study 利用天然沸石和灰泥基吸附剂从盐水中提取钠离子和钾离子的初步研究
IF 0.3 Pub Date : 2022-06-20 DOI: 10.15328/cb1276
G. Seilkhanova, A. Rakhym, Anastasiya Kan, A. Kenessova, Y. Mastai
In this work, sorbents based on natural zeolite (Z) and chamotte clay (ChC) treated with NaCl and HNO3 solutions were obtained to extract Na+ and K+ ions from saline water. The physicochemical characteristics of the obtained sorbents were studied by SEM, EDAX, and BET methods. It was found that successive treatment with NaCl and HNO3 solutions has a positive effect on the sorption properties of the studied materials. The maximum increase in the specific surface area from 4.5 m2/g to 39.3 m2/g is observed for acid-treated Z, and the specific surface area of ChC also increases almost 2-fold from 8.4 m2/g to 15.3 m2/g. Na+ and K+ ions are extracted from water due to ion exchange with Z and ChC cations. As a result of determining the cation exchange capacity (CEC) of the studied sorbents, it was found that treatment with a NaCl solution improves the ion exchange properties of the sorbent and leads to the formation of a “homoionic” form of aluminosilicates. Due to that the sorbents more easily enter ion exchange reactions. The authors established the sorption activity of the obtained materials based on natural Z and ChC with respect to Na+ and K+ cations. The maximum recovery rate is 28.45% for Na+ ions with the ChC-Na-H sorbent and 76.28% for K+ ions with the ChC-Na sorbent. Among Z-based sorbents, the most effective forms are Z-Na-H (15.44% Na+ recovery) and Z-Na (60.47% K+ recovery).
本研究以天然沸石(Z)和色粘土(ChC)为吸附剂,分别经NaCl和HNO3溶液处理,获得了从盐水中提取Na+和K+离子的吸附剂。采用扫描电镜(SEM)、电子能谱(EDAX)和BET等方法对所得吸附剂的物理化学特性进行了研究。结果表明,NaCl和HNO3溶液连续处理对材料的吸附性能有积极的影响。经酸处理的Z的比表面积从4.5 m2/g增加到39.3 m2/g, ChC的比表面积也从8.4 m2/g增加到15.3 m2/g,几乎增加了2倍。由于离子与Z和ChC阳离子交换,Na+和K+离子从水中被提取出来。通过测定所研究的吸附剂的阳离子交换容量(CEC),发现NaCl溶液处理提高了吸附剂的离子交换性能,并导致“同离子”形式的铝硅酸盐的形成。因此吸附剂更容易进入离子交换反应。作者建立了基于天然Z和ChC的材料对Na+和K+阳离子的吸附活性。ChC-Na- h吸附剂对Na+离子的最大回收率为28.45%,对K+离子的最大回收率为76.28%。在z基吸附剂中,Z-Na- h (Na+回收率15.44%)和Z-Na (K+回收率60.47%)是最有效的形式。
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引用次数: 0
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Chemical Bulletin of Kazakh National University
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