Pub Date : 2023-01-01DOI: 10.2298/hemind230921022s
Snezana Stankovic
Heat and mass transfer through textile fabrics play a crucial role in achieving optimal thermal comfort perception by a person. The governing properties of textile fabrics by which they influence heat and mass transfer from the human skin to the environment are thermal transport capacity, water vapor permeability, and air permeability. The transfer of liquid moisture through textiles is important for thermal comfort during frequent changes in physical activity or climate. Despite numerous studies on the transport properties of textile materials over the past years, investigation in this subject area is still needed. This special issue includes five articles that offer valuable information on the subject. Both commercial and specially designed textile structures were investigated within the presented studies with the ambitious goal of providing a new understanding of their transport properties. Within the first four papers presented, certain aspects of heat and mass transfer through textile materials were analyzed at the three scale levels: microscopic (fiber type), mesoscopic (yarn geometry and fineness), and macroscopic (fabric porosity) levels. The fifth article dealt with the influence of the seam type and the sewing thread fineness on the transport properties of the seamed structure.
{"title":"Transport properties and permeability of textile materials","authors":"Snezana Stankovic","doi":"10.2298/hemind230921022s","DOIUrl":"https://doi.org/10.2298/hemind230921022s","url":null,"abstract":"Heat and mass transfer through textile fabrics play a crucial role in achieving optimal thermal comfort perception by a person. The governing properties of textile fabrics by which they influence heat and mass transfer from the human skin to the environment are thermal transport capacity, water vapor permeability, and air permeability. The transfer of liquid moisture through textiles is important for thermal comfort during frequent changes in physical activity or climate. Despite numerous studies on the transport properties of textile materials over the past years, investigation in this subject area is still needed. This special issue includes five articles that offer valuable information on the subject. Both commercial and specially designed textile structures were investigated within the presented studies with the ambitious goal of providing a new understanding of their transport properties. Within the first four papers presented, certain aspects of heat and mass transfer through textile materials were analyzed at the three scale levels: microscopic (fiber type), mesoscopic (yarn geometry and fineness), and macroscopic (fabric porosity) levels. The fifth article dealt with the influence of the seam type and the sewing thread fineness on the transport properties of the seamed structure.","PeriodicalId":12913,"journal":{"name":"Hemijska Industrija","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135701172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.2298/hemind230103019t
Elena Tomovska, Lubos Hes, Koleta Zafirova
Comfort properties of clothing are one of the main indicators of clothing quality and have been widely investigated in the past decades. This research concentrates on the water vapour permeability of nylon pantyhose, by examining behaviours in the relaxed state, as well as under extension of knits of 100 %, comparative to wear conditions and above 100 %. Permetest apparatus was used to measure the water vapour permeability according to the standard ISO 11092. The results indicate that for very fine fabrics permeability stays constant under extension, while for fabrics above 44 dtex the water vapour permeability changes significantly with extension.
{"title":"Water vapour permeability of nylon pantyhose","authors":"Elena Tomovska, Lubos Hes, Koleta Zafirova","doi":"10.2298/hemind230103019t","DOIUrl":"https://doi.org/10.2298/hemind230103019t","url":null,"abstract":"Comfort properties of clothing are one of the main indicators of clothing quality and have been widely investigated in the past decades. This research concentrates on the water vapour permeability of nylon pantyhose, by examining behaviours in the relaxed state, as well as under extension of knits of 100 %, comparative to wear conditions and above 100 %. Permetest apparatus was used to measure the water vapour permeability according to the standard ISO 11092. The results indicate that for very fine fabrics permeability stays constant under extension, while for fabrics above 44 dtex the water vapour permeability changes significantly with extension.","PeriodicalId":12913,"journal":{"name":"Hemijska Industrija","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135784063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-02DOI: 10.2298/HEMIND201211008K
D. Korcok, Nada Trsic-Milanovic, M. Ilić, Bogdan Mitic, B. Djordjevic, N. Ivanovic
In recent decades, probiotic products have been increasingly used to prevent certain gastro-intestinal and urogenital disorders, to improve the general condition of the body and as a supplement to pharmacological therapy. They are most often registered as dietary supplements, and less often as drugs in the form of capsules, powders, and solutions. Optimization of technological processes of production and packaging of these products aims to maintain probiotic characteristics while adhering to all criteria during production that ensure quality, bioavailability and optimal therapeutic effects. In this paper, the importance of choosing primary and secondary packaging materials was explored with the aim of preserving the viability of probiotic cells in capsules for two years, i.e. during the shelf life. By comparing the applications of polyvinyl chloride (PVC) and PVC/polyvinylidene chloride/polyethylene blister foils, better protection of probiotic cells was observed by applying the multilayer foil. In addition, in this research, further improvements of probiotic cell protection were achieved by applying a secondary packing-flow pack bag with inert gas for storing multilayered blisters.
{"title":"Improving the viability and stability of a probiotic product with Saccharomyces boulardii DBVPG","authors":"D. Korcok, Nada Trsic-Milanovic, M. Ilić, Bogdan Mitic, B. Djordjevic, N. Ivanovic","doi":"10.2298/HEMIND201211008K","DOIUrl":"https://doi.org/10.2298/HEMIND201211008K","url":null,"abstract":"In recent decades, probiotic products have been increasingly used to prevent certain gastro-intestinal and urogenital disorders, to improve the general condition of the body and as a supplement to pharmacological therapy. They are most often registered as dietary supplements, and less often as drugs in the form of capsules, powders, and solutions. Optimization of technological processes of production and packaging of these products aims to maintain probiotic characteristics while adhering to all criteria during production that ensure quality, bioavailability and optimal therapeutic effects. In this paper, the importance of choosing primary and secondary packaging materials was explored with the aim of preserving the viability of probiotic cells in capsules for two years, i.e. during the shelf life. By comparing the applications of polyvinyl chloride (PVC) and PVC/polyvinylidene chloride/polyethylene blister foils, better protection of probiotic cells was observed by applying the multilayer foil. In addition, in this research, further improvements of probiotic cell protection were achieved by applying a secondary packing-flow pack bag with inert gas for storing multilayered blisters.","PeriodicalId":12913,"journal":{"name":"Hemijska Industrija","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68381718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-02DOI: 10.2298/HEMIND200807005S
M. Smiljanić, B. Radjenovic, Ž. Lazić, M. Radmilović-Radjenović, Milena Rasljic-Rafajilovic, Katarina Cvetanovic-Zobenica, E. Milinković, Ana Filipović
In this paper, fabrication of silicon microchannels with integrated obstacles by using 25 wt % tetramethylammonium hydroxide (TMAH) aqueous solution at the temperature of 80 o C is presented and analysed. We studied basic island patterns, which present union of two symmetrical parallelograms with the sides along predetermined crystallographic directions (2 . Acute angles of the parallelograms were smaller than 45 o . We have derived analytical relations for determining dimensions of the integrated obstacles. The developed etching technique provides reduction of the distance between the obstacles. Before the experiments, we performed simulations of pattern etching based on the level set method and presented evolution of the etched basic patterns for the predetermined crystallographic directions . Combination of basic patterns with sides along the and crystallographic directions is used to fabricate a matrix of two row of silicon obstacles in a microchannel. We obtained a good agreement between the experimental results and simulations. Our results enable simple and cost-effective fabrication of various complex microfluidic silicon platforms with integrated obstacles.
{"title":"Controllable arrangement of integrated obstacles in silicon microchannels etched in 25 wt.% TMAX","authors":"M. Smiljanić, B. Radjenovic, Ž. Lazić, M. Radmilović-Radjenović, Milena Rasljic-Rafajilovic, Katarina Cvetanovic-Zobenica, E. Milinković, Ana Filipović","doi":"10.2298/HEMIND200807005S","DOIUrl":"https://doi.org/10.2298/HEMIND200807005S","url":null,"abstract":"In this paper, fabrication of silicon microchannels with integrated obstacles by using 25 wt % tetramethylammonium hydroxide (TMAH) aqueous solution at the temperature of 80 o C is presented and analysed. We studied basic island patterns, which present union of two symmetrical parallelograms with the sides along predetermined crystallographic directions (2 . Acute angles of the parallelograms were smaller than 45 o . We have derived analytical relations for determining dimensions of the integrated obstacles. The developed etching technique provides reduction of the distance between the obstacles. Before the experiments, we performed simulations of pattern etching based on the level set method and presented evolution of the etched basic patterns for the predetermined crystallographic directions . Combination of basic patterns with sides along the and crystallographic directions is used to fabricate a matrix of two row of silicon obstacles in a microchannel. We obtained a good agreement between the experimental results and simulations. Our results enable simple and cost-effective fabrication of various complex microfluidic silicon platforms with integrated obstacles.","PeriodicalId":12913,"journal":{"name":"Hemijska Industrija","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44299609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-02DOI: 10.2298/HEMIND201214006P
A. Patarić, M. Mihailović, B. Marković, M. Sokić, A. Radovanović, B. Jordović
Microstructure assessment is crucial for the design and production of high-quality alloys such as cast aluminum alloy ingots. Along with the effect of a more homogeneous microstructure to result in much better mechanical properties, better as-cast alloy quality indicates a higher efficiency of the aluminum alloys production process. During the aluminum alloy solidification process many microstructural defects can occur, which deteriorate the mechanical properties and hence decrease the usability of such an ingot. Application of the electromagnetic field during the vertical continuous casting process significantly reduces occurrence of these defects. In the present study, EN AW 7075 alloy samples were cast with and without application of an electromagnetic field and examined regarding the microstructure, electrical conductivity, and changes in the phase composition. The obtained results clearly show that it is possible to decrease or avoid casting defects by the electromagnetic field application as verified by the microstructure characterization and quantification, electrical conductivity tests and differential thermal analysis (DTA).
微观结构评估对于设计和生产高质量合金（如铸铝合金锭）至关重要。除了更均匀的微观结构产生更好的机械性能的效果外，更好的铸态合金质量表明铝合金生产工艺的效率更高。在铝合金凝固过程中，可能会出现许多微观结构缺陷，这会降低机械性能，从而降低这种铸锭的可用性。在垂直连铸过程中应用电磁场显著减少了这些缺陷的发生。在本研究中，EN AW 7075合金样品在施加和不施加电磁场的情况下进行铸造，并检查微观结构、电导率和相组成的变化。通过微观结构表征和定量、电导率测试和差热分析（DTA）验证，所获得的结果清楚地表明，通过施加电磁场可以减少或避免铸造缺陷。
{"title":"Microstructure as an essential aspect of EN AW 7075 aluminum alloy quality influenced by electromagnetic field during continuous casting process","authors":"A. Patarić, M. Mihailović, B. Marković, M. Sokić, A. Radovanović, B. Jordović","doi":"10.2298/HEMIND201214006P","DOIUrl":"https://doi.org/10.2298/HEMIND201214006P","url":null,"abstract":"Microstructure assessment is crucial for the design and production of high-quality alloys such as cast aluminum alloy ingots. Along with the effect of a more homogeneous microstructure to result in much better mechanical properties, better as-cast alloy quality indicates a higher efficiency of the aluminum alloys production process. During the aluminum alloy solidification process many microstructural defects can occur, which deteriorate the mechanical properties and hence decrease the usability of such an ingot. Application of the electromagnetic field during the vertical continuous casting process significantly reduces occurrence of these defects. In the present study, EN AW 7075 alloy samples were cast with and without application of an electromagnetic field and examined regarding the microstructure, electrical conductivity, and changes in the phase composition. The obtained results clearly show that it is possible to decrease or avoid casting defects by the electromagnetic field application as verified by the microstructure characterization and quantification, electrical conductivity tests and differential thermal analysis (DTA).","PeriodicalId":12913,"journal":{"name":"Hemijska Industrija","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48828079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-04DOI: 10.2298/hemind200320027v
Anita Vakula, B. Pavlić, Aleksandra Tepic-Horecki, M. Jokanović, Tatjana Daničić, Jovana Dulić, Zdravko M. Šumić
Sweet cherries ( Prunus avium L.) were vacuum dried at different temperatures in the range between 50 and 70 o C and different pressures between 20 and 200 mbar. Seven mathematical models (Henderson-Pabis, Modified Henderson-Pabis, Simplified Fick’s diffusion, Peleg, Logarithmic, Two term and Midilli et al. ) were used for description of the vacuum drying process and the Midilli et al. model was selected as the most suitable with the highest mean value of coefficient of determination ( R 2 =0.9985) and the lowest mean values of the average absolute relative deviation (AARD=0.90 %), root mean square error (RMSE=0.0061) and the reduced chi-square ( χ 2 =0.0001). Seven textural properties (shear force, penetration force, hardness, springiness, cohesiveness, gumminess and chewiness) were investigated in all dried sweet cherry samples. The results indicated that the pressure influenced the textural properties of sweet cherries during vacuum drying since the minimum values of all investigated texture properties were obtained in samples dried at the pressure of 200 mbar, while the maximum values were obtained at 20 and 65 mbar. It also was noticed that the temperature influenced the textural properties in the temperature range investigated, but not as significantly as it was the case of the pressure influence.
甜樱桃(Prunus avium L.)在50至70℃的不同温度和20至200毫巴的不同压力下进行真空干燥。采用了7个数学模型(Henderson-Pabis、Modified Henderson-Pabis、Simplified Fick’s diffusion、Peleg、Logarithmic、Two term和Midilli et al.)来描述真空干燥过程，选择了决定系数均值最高(r2 =0.9985)、平均绝对相对偏差均值最低(AARD= 0.90%)的Midilli et al.模型。均方根误差(RMSE=0.0061)和简化卡方(χ 2 =0.0001)。研究了甜樱桃干样品的剪切力、渗透力、硬度、弹性、黏结性、胶性和咀嚼性等7项结构特性。结果表明，压力对真空干燥过程中甜樱桃的结构特性有一定的影响，所有研究的结构特性都是在压力为200 mbar时达到最小值，而在压力为20和65 mbar时达到最大值。还注意到，在所研究的温度范围内，温度对纹理性能的影响，但不像压力影响那么显著。
{"title":"Sweet cherry (Prunus avium L.) vacuum drying: Kinetics modelling and textural properties","authors":"Anita Vakula, B. Pavlić, Aleksandra Tepic-Horecki, M. Jokanović, Tatjana Daničić, Jovana Dulić, Zdravko M. Šumić","doi":"10.2298/hemind200320027v","DOIUrl":"https://doi.org/10.2298/hemind200320027v","url":null,"abstract":"Sweet cherries ( Prunus avium L.) were vacuum dried at different temperatures in the range between 50 and 70 o C and different pressures between 20 and 200 mbar. Seven mathematical models (Henderson-Pabis, Modified Henderson-Pabis, Simplified Fick’s diffusion, Peleg, Logarithmic, Two term and Midilli et al. ) were used for description of the vacuum drying process and the Midilli et al. model was selected as the most suitable with the highest mean value of coefficient of determination ( R 2 =0.9985) and the lowest mean values of the average absolute relative deviation (AARD=0.90 %), root mean square error (RMSE=0.0061) and the reduced chi-square ( χ 2 =0.0001). Seven textural properties (shear force, penetration force, hardness, springiness, cohesiveness, gumminess and chewiness) were investigated in all dried sweet cherry samples. The results indicated that the pressure influenced the textural properties of sweet cherries during vacuum drying since the minimum values of all investigated texture properties were obtained in samples dried at the pressure of 200 mbar, while the maximum values were obtained at 20 and 65 mbar. It also was noticed that the temperature influenced the textural properties in the temperature range investigated, but not as significantly as it was the case of the pressure influence.","PeriodicalId":12913,"journal":{"name":"Hemijska Industrija","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2020-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43049066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-04DOI: 10.2298/hemind200424031s
M. Saldaña, Freddy Rodríguez, Anyelo Rojas, K. Pérez, Hugo Javier Angulo Palma
Multivariate models are a useful tool when studying the effects of independent variables on one or more dependent variables, since this approach allows modeling of the dynamics of complex systems based on simple analytical models with considerable certainty. Due to the decrease in the copper oxide mineral grades, leaching of copper sulfide minerals (secondary sulfides) has positioned itself as a benchmark of operation for the Chilean mining industry. The present work proposes the study of the effects of sulfuric acid, chloride concentration and time on the extraction of copper from sulfuric minerals (chalcocite), considering an experimental design, the surface optimization methodology and the adjustment of a quadratic model. The experimental data were adjusted by multiple regression analysis and were statistically analyzed. A model was developed to represent the copper extraction from the Cu 2 S mineral as a function of the statistically significant variables (chloride concentration and time) that contribute to explain the variation of the response variable under the set of parameters sampled.
{"title":"Development of an empirical model for copper extraction from chalcocite in chloride media","authors":"M. Saldaña, Freddy Rodríguez, Anyelo Rojas, K. Pérez, Hugo Javier Angulo Palma","doi":"10.2298/hemind200424031s","DOIUrl":"https://doi.org/10.2298/hemind200424031s","url":null,"abstract":"Multivariate models are a useful tool when studying the effects of independent variables on one or more dependent variables, since this approach allows modeling of the dynamics of complex systems based on simple analytical models with considerable certainty. Due to the decrease in the copper oxide mineral grades, leaching of copper sulfide minerals (secondary sulfides) has positioned itself as a benchmark of operation for the Chilean mining industry. The present work proposes the study of the effects of sulfuric acid, chloride concentration and time on the extraction of copper from sulfuric minerals (chalcocite), considering an experimental design, the surface optimization methodology and the adjustment of a quadratic model. The experimental data were adjusted by multiple regression analysis and were statistically analyzed. A model was developed to represent the copper extraction from the Cu 2 S mineral as a function of the statistically significant variables (chloride concentration and time) that contribute to explain the variation of the response variable under the set of parameters sampled.","PeriodicalId":12913,"journal":{"name":"Hemijska Industrija","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2020-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43189127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Modeling of flotation processes is complex due to the large number of variables involved and the lack of knowledge on the impact of operational parameters on the response(s), and given this problem, machine learning algorithms emerge as an alternative interesting when modeling dynamic processes. In this work, different artificial neural network (ANN) architectures for modeling the mineral concentrate in a rougher-cleaner-scavenger (RCS) circuit based on the main process variables are generated (variables as the recovery of the rougher, cleaner and scavenger cells, along with disaggregated variables). Analysis of the global sensitivity was performed to study the importance of the individual and joint performances of the stages of the flotation circuit, reflected by sensitivity indicators that allow to infer the impact that the stages and operational parameters produce on the dependent variables (mineral concentrate in rougher, cleaner and scavenger cells, in addition to the global concentration in the RCS circuit). It should be noted that the ANN is a useful tool for modeling dynamic systems such as flotation, while sensitivity analysis shows that the operation of the three threads turns out to be crucial for the subsequent evaluation of the circuit, while the Unbundled variables that most interact with the overall recovery are gas flow rate, bubble and particle diameters, bubble velocity, particle density, and surface tension.
{"title":"Global sensitivity analyses of a neural networks model for a flotation circuit","authors":"M. Saldaña, Luís Ayala, David Torres, N. Toro","doi":"10.2298/hemind20060523s","DOIUrl":"https://doi.org/10.2298/hemind20060523s","url":null,"abstract":"Modeling of flotation processes is complex due to the large number of variables involved and the lack of knowledge on the impact of operational parameters on the response(s), and given this problem, machine learning algorithms emerge as an alternative interesting when modeling dynamic processes. In this work, different artificial neural network (ANN) architectures for modeling the mineral concentrate in a rougher-cleaner-scavenger (RCS) circuit based on the main process variables are generated (variables as the recovery of the rougher, cleaner and scavenger cells, along with disaggregated variables). Analysis of the global sensitivity was performed to study the importance of the individual and joint performances of the stages of the flotation circuit, reflected by sensitivity indicators that allow to infer the impact that the stages and operational parameters produce on the dependent variables (mineral concentrate in rougher, cleaner and scavenger cells, in addition to the global concentration in the RCS circuit). It should be noted that the ANN is a useful tool for modeling dynamic systems such as flotation, while sensitivity analysis shows that the operation of the three threads turns out to be crucial for the subsequent evaluation of the circuit, while the Unbundled variables that most interact with the overall recovery are gas flow rate, bubble and particle diameters, bubble velocity, particle density, and surface tension.","PeriodicalId":12913,"journal":{"name":"Hemijska Industrija","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44707194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.2298/HEMIND200114012M
Dragana V. Medić, Snežana Milić, S. Alagić, I. Djordjevic, S. Dimitrijević
Development of lithium-ion batteries (LIBs) during the latest decades resulted in improved performances of the new integrated cathode materials and in their wide applications. This rapid expansion of new materials led to the intensive replacement of the old-fashioned, traditional materials and increased a simultaneous accumulation of both kinds of materials at extremely hazardous electronic waste sites, which additionally increased an urgent need for their recycling. Most importantly, in this way, spent LIBs may further serve as a significant source of valuable metals such as Li and cobalt. However, one of the key problems in LIBs recycling is the absence of a precise battery classification/sorting based on the chemical composition of the used cathode material. In this paper, characterization of the cathode material was performed regarding chemical composition of 40 samples of spent LIBs using inductively coupled plasma - optical emission spectrometry and X-ray diffraction. Preparation of the samples, (pretreatment) included: discharging, dismantling, separation of the main components (cathode, anode and the separator), and detachment of the cathode material from the aluminium foil. The obtained results showed that, in the investigated commercially available LIBs, lithium cobalt oxide was the most frequently used (cathode) material.
{"title":"Classification of spent Li-ion batteries based on ICP-OES/X-ray characterization of the cathode materials","authors":"Dragana V. Medić, Snežana Milić, S. Alagić, I. Djordjevic, S. Dimitrijević","doi":"10.2298/HEMIND200114012M","DOIUrl":"https://doi.org/10.2298/HEMIND200114012M","url":null,"abstract":"Development of lithium-ion batteries (LIBs) during the latest decades resulted in improved performances of the new integrated cathode materials and in their wide applications. This rapid expansion of new materials led to the intensive replacement of the old-fashioned, traditional materials and increased a simultaneous accumulation of both kinds of materials at extremely hazardous electronic waste sites, which additionally increased an urgent need for their recycling. Most importantly, in this way, spent LIBs may further serve as a significant source of valuable metals such as Li and cobalt. However, one of the key problems in LIBs recycling is the absence of a precise battery classification/sorting based on the chemical composition of the used cathode material. In this paper, characterization of the cathode material was performed regarding chemical composition of 40 samples of spent LIBs using inductively coupled plasma - optical emission spectrometry and X-ray diffraction. Preparation of the samples, (pretreatment) included: discharging, dismantling, separation of the main components (cathode, anode and the separator), and detachment of the cathode material from the aluminium foil. The obtained results showed that, in the investigated commercially available LIBs, lithium cobalt oxide was the most frequently used (cathode) material.","PeriodicalId":12913,"journal":{"name":"Hemijska Industrija","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46366880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.2298/hemind200304018p
J. Prodanović, Bojana Šarić, M. Šćiban, D. Kukić, V. Vasić, S. Popović, M. Antov
Natural coagulants from a crude water extract of common bean seed showed very good efficiency of turbidity removal from water of ~89 % under optimal coagulation conditions, which were determined using response surface methodology (RSM). However, they also increased the content of organic matter in treated model water by ~66 %, which is the main drawback of usage of natural coagulants, in general. Thus, ultrafiltration was applied for processing of the crude water extract in order to separate biomolecules, which exhibit the coagulation activity. Four fractions obtained by ultrafiltration were applied in coagulation tests under the same conditions as the crude extract, and the 4 th fraction (molecules with molecular weights >30 kDa) with the predominant content of proteins with molecular weights 50 – 60 kDa, achieved almost as high efficiency of turbidity removal (75 %) as the crude extract. At the same time, the content of organic matter in treated water increased just for 16 % in comparison to the blank (model water processed in the same way but without coagulant). After optimization of process parameters by RSM for usage of the 4 th fraction, the coagulation activity increased further to 80 %.
{"title":"Ultrafiltration as a simple purification method of a water extract of common bean seed as a natural coagulant","authors":"J. Prodanović, Bojana Šarić, M. Šćiban, D. Kukić, V. Vasić, S. Popović, M. Antov","doi":"10.2298/hemind200304018p","DOIUrl":"https://doi.org/10.2298/hemind200304018p","url":null,"abstract":"Natural coagulants from a crude water extract of common bean seed showed very good efficiency of turbidity removal from water of ~89 % under optimal coagulation conditions, which were determined using response surface methodology (RSM). However, they also increased the content of organic matter in treated model water by ~66 %, which is the main drawback of usage of natural coagulants, in general. Thus, ultrafiltration was applied for processing of the crude water extract in order to separate biomolecules, which exhibit the coagulation activity. Four fractions obtained by ultrafiltration were applied in coagulation tests under the same conditions as the crude extract, and the 4 th fraction (molecules with molecular weights >30 kDa) with the predominant content of proteins with molecular weights 50 – 60 kDa, achieved almost as high efficiency of turbidity removal (75 %) as the crude extract. At the same time, the content of organic matter in treated water increased just for 16 % in comparison to the blank (model water processed in the same way but without coagulant). After optimization of process parameters by RSM for usage of the 4 th fraction, the coagulation activity increased further to 80 %.","PeriodicalId":12913,"journal":{"name":"Hemijska Industrija","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49620125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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