A large number of pesticide active ingredients have been registered and marketed for pest control purposes around the world. Most pesticides, including carbamates are resistant to chemical and natural photochemical degradation, so that developing adequate methods for remediation of contaminated waters is a priority. There are different methods for removing carbamate pesticide residues from water, and photodegradation methods are discussed in this study. According to literature data, the most beneficial photochemical processes for removal of pesticides from water are two well-known Advanced Oxidation Processes: heterogeneous photocatalysis with semiconductor oxides TiO2 and ZnO, and homogeneous photo-Fenton treatment, as well as direct UV photolysis. Photochemical investigations may contribute toward our better understanding of carbamate pesticide behavior in the environment, i.e. more information on the degradation time of active ingredients, their activity and environmental fate can be obtained by studying the kinetics of any photochemical reaction.
{"title":"Photochemical processes for removal of carbamate pesticides from water","authors":"A. Tomašević, S. Petrović, D. Mijin","doi":"10.5937/savteh1902072t","DOIUrl":"https://doi.org/10.5937/savteh1902072t","url":null,"abstract":"A large number of pesticide active ingredients have been registered and marketed for pest control purposes around the world. Most pesticides, including carbamates are resistant to chemical and natural photochemical degradation, so that developing adequate methods for remediation of contaminated waters is a priority. There are different methods for removing carbamate pesticide residues from water, and photodegradation methods are discussed in this study. According to literature data, the most beneficial photochemical processes for removal of pesticides from water are two well-known Advanced Oxidation Processes: heterogeneous photocatalysis with semiconductor oxides TiO2 and ZnO, and homogeneous photo-Fenton treatment, as well as direct UV photolysis. Photochemical investigations may contribute toward our better understanding of carbamate pesticide behavior in the environment, i.e. more information on the degradation time of active ingredients, their activity and environmental fate can be obtained by studying the kinetics of any photochemical reaction.","PeriodicalId":7216,"journal":{"name":"Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75838103","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}
M. Cakic, G. Nikolić, Ž. Mitić, Slobodan Glišić, D. Cvetković, L. Stanojević
Nanotechnology refers to the branch of science and engineering dedicated to materials, having dimensions in the order of 100th nm or less. Many ions of transition or noble metals can form complex compounds of nanoparticle size. These compounds are of scientific and practical interest, because of their proven or potential application in different areas. Nano-biocomplexes of iron, copper, cobalt and silver with oligosaccharides and their derivatives are important in medicine, cosmetics and veterinary medicine. The development of new nano-biocomplexes based on oligosaccharides and their derivatives and non-toxic or "green" silver nanoparticles syntheses, the influence of the ligand constitution on the synthesis outcome, stability, structure and pharmaco-biological properties are the subject of this paper.
{"title":"Nano-biocomplexes based on oligosaccharides and their derivates","authors":"M. Cakic, G. Nikolić, Ž. Mitić, Slobodan Glišić, D. Cvetković, L. Stanojević","doi":"10.5937/savteh1902016c","DOIUrl":"https://doi.org/10.5937/savteh1902016c","url":null,"abstract":"Nanotechnology refers to the branch of science and engineering dedicated to materials, having dimensions in the order of 100th nm or less. Many ions of transition or noble metals can form complex compounds of nanoparticle size. These compounds are of scientific and practical interest, because of their proven or potential application in different areas. Nano-biocomplexes of iron, copper, cobalt and silver with oligosaccharides and their derivatives are important in medicine, cosmetics and veterinary medicine. The development of new nano-biocomplexes based on oligosaccharides and their derivatives and non-toxic or \"green\" silver nanoparticles syntheses, the influence of the ligand constitution on the synthesis outcome, stability, structure and pharmaco-biological properties are the subject of this paper.","PeriodicalId":7216,"journal":{"name":"Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72649920","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}
Hristina Stanković, A. Krstić, Miljana Rubežić, M. Vasić, M. Ranđelović, A. Zarubica
The TiO2/carbonized materials in composites provide a synergistic effect of adsorption and photocatalysis. The activated carbon or carbonized material can be prepared using various raw materials that present agricultural waste. The most commonly used process for the preparation of the activated carbon (AC)/carbonized material is chemical activation. Chemical activation produces the activated carbon with a good surface area and pore system, which contributes to better adsorption of organic pollutants. The TiO2/AC composite materials can be prepared by sol-gel, hydrothermal and metal organic chemical vapor deposition (MOCVD) techniques. The most commonly used techniques for characterization of the TiO2/AC materials are XRD, BET, TG Analysis and UV-Vis DRS, and will therefore be discussed in this paper. The TiO2/AC composite materials have shown significant efficiency in removal of organic pollutants from aqueous solutions. The adsorption process of organic pollutants can be affected by various process parameters that will be observed in this paper.
{"title":"TiO2 modified with carbonized materials: Photocatalysis/adsorption of organic pollutants from aqueous solution: A short review","authors":"Hristina Stanković, A. Krstić, Miljana Rubežić, M. Vasić, M. Ranđelović, A. Zarubica","doi":"10.5937/savteh1902082s","DOIUrl":"https://doi.org/10.5937/savteh1902082s","url":null,"abstract":"The TiO2/carbonized materials in composites provide a synergistic effect of adsorption and photocatalysis. The activated carbon or carbonized material can be prepared using various raw materials that present agricultural waste. The most commonly used process for the preparation of the activated carbon (AC)/carbonized material is chemical activation. Chemical activation produces the activated carbon with a good surface area and pore system, which contributes to better adsorption of organic pollutants. The TiO2/AC composite materials can be prepared by sol-gel, hydrothermal and metal organic chemical vapor deposition (MOCVD) techniques. The most commonly used techniques for characterization of the TiO2/AC materials are XRD, BET, TG Analysis and UV-Vis DRS, and will therefore be discussed in this paper. The TiO2/AC composite materials have shown significant efficiency in removal of organic pollutants from aqueous solutions. The adsorption process of organic pollutants can be affected by various process parameters that will be observed in this paper.","PeriodicalId":7216,"journal":{"name":"Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88000754","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}
J. Mitrović, Miljana Radović-Vučić, M. Kostić, N. Velinov, S. Najdanović, D. Bojić, A. Bojić
The effects of various organic and inorganic anions on decolorization of textile dye Reactive Orange 16 by means of hydroxyl radicals have been studied. These anions are commonly present in wastewaters from textile industry and include chloride, sulfate, carbonate/bicarbonate, nitrate and acetate anions. The experiments were conducted in the presence of different concentrations of anions and at different initial pH values in a batch photoreactor equipped with UV-C (254 nm) lamps in the presence of hydrogen peroxide. It was obtained that decolorization efficiency was significantly affected by nature and concentration of the investigated anions. An inhibitory effect of acetate anions increased with increasing in their concentration and depended on whether protonated or deprotonated forms are favored. Carbonate anion showed specific, both positive and negative influence, depending on its concentration. Influence of bicarbonate, nitrate and chloride was more prominent at their higher initial concentrations. The presence of sulfate did not have noticeable impact on decolorization of RO16 dye under investigated conditions.
{"title":"The effect of anions on decolorization of textile azo dye Reactive Orange 16 with UV/H2O2 process","authors":"J. Mitrović, Miljana Radović-Vučić, M. Kostić, N. Velinov, S. Najdanović, D. Bojić, A. Bojić","doi":"10.5937/SAVTEH1901033M","DOIUrl":"https://doi.org/10.5937/SAVTEH1901033M","url":null,"abstract":"The effects of various organic and inorganic anions on decolorization of textile dye Reactive Orange 16 by means of hydroxyl radicals have been studied. These anions are commonly present in wastewaters from textile industry and include chloride, sulfate, carbonate/bicarbonate, nitrate and acetate anions. The experiments were conducted in the presence of different concentrations of anions and at different initial pH values in a batch photoreactor equipped with UV-C (254 nm) lamps in the presence of hydrogen peroxide. It was obtained that decolorization efficiency was significantly affected by nature and concentration of the investigated anions. An inhibitory effect of acetate anions increased with increasing in their concentration and depended on whether protonated or deprotonated forms are favored. Carbonate anion showed specific, both positive and negative influence, depending on its concentration. Influence of bicarbonate, nitrate and chloride was more prominent at their higher initial concentrations. The presence of sulfate did not have noticeable impact on decolorization of RO16 dye under investigated conditions.","PeriodicalId":7216,"journal":{"name":"Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91077945","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}
Pot marigold (Calendula officinalis L.) contains various bioactive compounds such as flavonoids, tannins, saponosides, carotenoids, triterpene alcohols, polysaccharides, amino acids, and essential oil. The extract of pot marigold flower has a benefit to the skin due to the presence of flavonoids that possess the anti-inflammatory, astringent, antifungal, and antiseptic effects. The aim of this study was to apply the ultrasound-assisted extraction as an advanced extraction technique and to investigate the impact of extraction time (5-35 min), ethanol concentration (20-80%, v/v), and extraction temperature (30-70 °C) on the total flavonoid content of pot marigold flower at the liquid-to-solid ratio of 20 cm3 g-1. The total flavonoids content of the extracts was determined spectrophotometrically with aluminium (III) chloride. The modeling of ultrasound-assisted extraction was carried out using a Box-Behnken design. Thus found optimal extraction conditions were the extraction time of 29 min, 39.6% (v/v) ethanol, and extraction temperature of 64.2 °C. The experimental value (220.2 mg 100 g-1 d.w.) of the total flavonoid content under optimal conditions was in a good agreement with the predicted value (221.5 mg 100 g-1 d.w.). According to the results of statistical analysis, the proposed second-order polynomial equation can be used to describe the extraction of flavonoids and to predict the total flavonoid content. The extraction procedure can be accepted from the point of the pharmaceutical application due to the use of ethanol as a representative of green solvents. The extraction time was shorter compared with other conventional extraction techniques.
{"title":"The optimization of ultrasound-assisted extraction of total flavonoids from pot marigold (Calendulae officinalis L.) flowers","authors":"S. Žerajić, I. Savić-Gajić, I. Savić, G. Nikolić","doi":"10.5937/SAVTEH1901010Z","DOIUrl":"https://doi.org/10.5937/SAVTEH1901010Z","url":null,"abstract":"Pot marigold (Calendula officinalis L.) contains various bioactive compounds such as flavonoids, tannins, saponosides, carotenoids, triterpene alcohols, polysaccharides, amino acids, and essential oil. The extract of pot marigold flower has a benefit to the skin due to the presence of flavonoids that possess the anti-inflammatory, astringent, antifungal, and antiseptic effects. The aim of this study was to apply the ultrasound-assisted extraction as an advanced extraction technique and to investigate the impact of extraction time (5-35 min), ethanol concentration (20-80%, v/v), and extraction temperature (30-70 °C) on the total flavonoid content of pot marigold flower at the liquid-to-solid ratio of 20 cm3 g-1. The total flavonoids content of the extracts was determined spectrophotometrically with aluminium (III) chloride. The modeling of ultrasound-assisted extraction was carried out using a Box-Behnken design. Thus found optimal extraction conditions were the extraction time of 29 min, 39.6% (v/v) ethanol, and extraction temperature of 64.2 °C. The experimental value (220.2 mg 100 g-1 d.w.) of the total flavonoid content under optimal conditions was in a good agreement with the predicted value (221.5 mg 100 g-1 d.w.). According to the results of statistical analysis, the proposed second-order polynomial equation can be used to describe the extraction of flavonoids and to predict the total flavonoid content. The extraction procedure can be accepted from the point of the pharmaceutical application due to the use of ethanol as a representative of green solvents. The extraction time was shorter compared with other conventional extraction techniques.","PeriodicalId":7216,"journal":{"name":"Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82167047","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}
In Bosnia and Herzegovina, climate change is increasingly considered to be the matter of key strategic importance, especially by local authorities and the academic community. The State development vision is that by 2025 Bosnia and Herzegovina (B&H) will be a sustainable and progressive 'green economy'. The implementation of measures for the reduction of greenhouse gases emission is an optimal opportunity and a chance to start a technological transition with international professional and financial help. In B&H, through consultative activities, seven priority sectors for the adaptation to climate changes were identified: agriculture, biodiversity and vulnerable ecosystems, energy (hydro-energy), forestry, public health, tourism and water resources/water management. Water management and agriculture are considered as main priorities that have a significant impact on other sectors. Having in mind its descriptive character and the characteristic of the problem solving at the very beginning, the backcasting approach is much more convenient for solving long-term problems and for offering long-term sustainable solutions. The aim of this paper is the identification of optimal technologies in the water management sector using the backcasting approach which can be applied in B&H, and their analysis through the TNAssess software to evaluate their acceptability and the possibilities of their use in B&H.
{"title":"The selection of technologies in the water management sector in Bosnia and Herzegovina for the reduction of GHG emissions by using Backcasting and the assessment methods for technology needs","authors":"Đ. Vojinović, M. Maksimović","doi":"10.5937/SAVTEH1901019V","DOIUrl":"https://doi.org/10.5937/SAVTEH1901019V","url":null,"abstract":"In Bosnia and Herzegovina, climate change is increasingly considered to be the matter of key strategic importance, especially by local authorities and the academic community. The State development vision is that by 2025 Bosnia and Herzegovina (B&H) will be a sustainable and progressive 'green economy'. The implementation of measures for the reduction of greenhouse gases emission is an optimal opportunity and a chance to start a technological transition with international professional and financial help. In B&H, through consultative activities, seven priority sectors for the adaptation to climate changes were identified: agriculture, biodiversity and vulnerable ecosystems, energy (hydro-energy), forestry, public health, tourism and water resources/water management. Water management and agriculture are considered as main priorities that have a significant impact on other sectors. Having in mind its descriptive character and the characteristic of the problem solving at the very beginning, the backcasting approach is much more convenient for solving long-term problems and for offering long-term sustainable solutions. The aim of this paper is the identification of optimal technologies in the water management sector using the backcasting approach which can be applied in B&H, and their analysis through the TNAssess software to evaluate their acceptability and the possibilities of their use in B&H.","PeriodicalId":7216,"journal":{"name":"Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88973519","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}
Danica Bogdanovic, Tatjana Anđelković, Ivana T. Kostić, G. Kocic
The aim of this paper is the development of the method for determination of five phthalates in white spirits. Dimethyl phthalate (DMP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DOP) were extracted from white spirits by the optimized liquid-liquid extraction (LLE) method. In order to determine the best method for phthalate determination, LLE procedure was optimized by changing the following parameters: the number of extraction repetitions (1-4), the partial removal of ethanol by evaporation from alcoholic samples prior extraction, the type of agitation and the extraction time. Quantification was achieved by gas chromatography-mass spectrometry (GC-MS) with di-n-butyl adipate (DBA) as internal standard. Phthalates were analyzed using a single ion monitoring (SIM) mode and a base ion for each phthalate was chosen (m/z 149 for DBP, BBP, DEHP and DOP and m/z 163 for DMP). The results show that the most effective phthalate extraction with n-hexane as a solvent is achieved with agitation by hand shaking with one-step extraction. Evaporation of ethanol from alcohol drinks provided the increased recovery value for DMP extraction but did not have an impact on the recovery values of DBP, BBP, DEHP and DOP extractions from the samples.
{"title":"Simultaneous determination of five phthalates in white spirits using liquid-liquid extraction followed by gas chromatography-mass spectrometry","authors":"Danica Bogdanovic, Tatjana Anđelković, Ivana T. Kostić, G. Kocic","doi":"10.5937/SAVTEH1901059B","DOIUrl":"https://doi.org/10.5937/SAVTEH1901059B","url":null,"abstract":"The aim of this paper is the development of the method for determination of five phthalates in white spirits. Dimethyl phthalate (DMP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DOP) were extracted from white spirits by the optimized liquid-liquid extraction (LLE) method. In order to determine the best method for phthalate determination, LLE procedure was optimized by changing the following parameters: the number of extraction repetitions (1-4), the partial removal of ethanol by evaporation from alcoholic samples prior extraction, the type of agitation and the extraction time. Quantification was achieved by gas chromatography-mass spectrometry (GC-MS) with di-n-butyl adipate (DBA) as internal standard. Phthalates were analyzed using a single ion monitoring (SIM) mode and a base ion for each phthalate was chosen (m/z 149 for DBP, BBP, DEHP and DOP and m/z 163 for DMP). The results show that the most effective phthalate extraction with n-hexane as a solvent is achieved with agitation by hand shaking with one-step extraction. Evaporation of ethanol from alcohol drinks provided the increased recovery value for DMP extraction but did not have an impact on the recovery values of DBP, BBP, DEHP and DOP extractions from the samples.","PeriodicalId":7216,"journal":{"name":"Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83577609","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}
V. Savic, S. Sunarić, J. Zivkovic, A. Stamenković, I. Nikolic, Ana Tačić, V. Nikolić
Pessaries with clindamycin phosphate as active component were prepared by moulding. Glycerol-gelatin basis was used as the hydrophilic basis. The pessaries were made with and without the surface-active agent Tween 80 as an excipient. The content of clindamycin phosphate in all samples was determined by high performance liquid chromatography (HPLC) based on the calibration curve of clindamycin phosphate standard solution. The clindamycin phosphate content in the glycerol-gelatin pessaries with or without Tween 80 was optimal. Preparation of extemporaneous (magistral) medicines provides personalization of therapy and the possibility of selection of the most appropriate basis for the specific active substance, which also influences the effectiveness of the therapy. The active substance content in the magistral preparations is not subject to veri-fication in the everyday pharmacy practice. However, by validating the technological process of manufacture and by controlling the quality of the obtained preparations, the choice of the basis in the magistral medicine preparation can be optimized. In this manner, the guidelines for the galenic preparation, including pessaries, can be given to ensure their optimal therapeutic effect.
{"title":"Determination of clindamycin phosphate in extemporaneously prepared pessaries with glycerol-gelatin basis","authors":"V. Savic, S. Sunarić, J. Zivkovic, A. Stamenković, I. Nikolic, Ana Tačić, V. Nikolić","doi":"10.5937/savteh1902066s","DOIUrl":"https://doi.org/10.5937/savteh1902066s","url":null,"abstract":"Pessaries with clindamycin phosphate as active component were prepared by moulding. Glycerol-gelatin basis was used as the hydrophilic basis. The pessaries were made with and without the surface-active agent Tween 80 as an excipient. The content of clindamycin phosphate in all samples was determined by high performance liquid chromatography (HPLC) based on the calibration curve of clindamycin phosphate standard solution. The clindamycin phosphate content in the glycerol-gelatin pessaries with or without Tween 80 was optimal. Preparation of extemporaneous (magistral) medicines provides personalization of therapy and the possibility of selection of the most appropriate basis for the specific active substance, which also influences the effectiveness of the therapy. The active substance content in the magistral preparations is not subject to veri-fication in the everyday pharmacy practice. However, by validating the technological process of manufacture and by controlling the quality of the obtained preparations, the choice of the basis in the magistral medicine preparation can be optimized. In this manner, the guidelines for the galenic preparation, including pessaries, can be given to ensure their optimal therapeutic effect.","PeriodicalId":7216,"journal":{"name":"Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75273025","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}
Marija Egerić, K. Stanković, Radojka Vujasin, L. Matović, Đ. Petrović, A. Devecerski, K. Kumrić
Hexavalent chromium is a highly toxic pollutant that exists in industrial wastewater effluents. The efficient removal of Cr(VI) from these effluents before their discharging into the environment is of great importance. Biopolymer chitosan was used as an adsorbent for the removal of Cr(VI) ions from aqueous solutions. The adsorbent characterization was carried out by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. Batch adsorption experiments were conducted to evaluate the effects of different parameters, such as contact time, solution pH, adsorbent dose, initial Cr(VI) concentration and ionic strength, on Cr(VI) removal. The obtained results revealed that the adsorption equilibrium was accomplished within 60 min. The adsorption was highly dependent on the solution pH and the maximum removal of Cr(VI) occured in the pH range 2.0 – 3.5. Analysis of kinetic parameters of Cr(VI) adsorption showed that pseudo-second order model described the kinetics for the investigated system. The data were fitted using two equilibrium adsorption models – Langmuir and Freundlich isotherm. The adsorption equilibrium data fit the Langmuir equation and the maximum adsorption capacity was found to be 91.4 mg g-1. The presence of co-existing anions at higher concentrations significantly reduced the removal of Cr(VI) by chitosan. According to the presented results, it can be concluded that biopolymer chitosan has a great potential for application in the treatment of chromium contaminated wastewaters.
{"title":"Investigation of adsorption performance of chitosan for the removal of hexavalent chromium from aqueous solutions","authors":"Marija Egerić, K. Stanković, Radojka Vujasin, L. Matović, Đ. Petrović, A. Devecerski, K. Kumrić","doi":"10.5937/savteh1902058e","DOIUrl":"https://doi.org/10.5937/savteh1902058e","url":null,"abstract":"Hexavalent chromium is a highly toxic pollutant that exists in industrial wastewater effluents. The efficient removal of Cr(VI) from these effluents before their discharging into the environment is of great importance. Biopolymer chitosan was used as an adsorbent for the removal of Cr(VI) ions from aqueous solutions. The adsorbent characterization was carried out by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. Batch adsorption experiments were conducted to evaluate the effects of different parameters, such as contact time, solution pH, adsorbent dose, initial Cr(VI) concentration and ionic strength, on Cr(VI) removal. The obtained results revealed that the adsorption equilibrium was accomplished within 60 min. The adsorption was highly dependent on the solution pH and the maximum removal of Cr(VI) occured in the pH range 2.0 – 3.5. Analysis of kinetic parameters of Cr(VI) adsorption showed that pseudo-second order model described the kinetics for the investigated system. The data were fitted using two equilibrium adsorption models – Langmuir and Freundlich isotherm. The adsorption equilibrium data fit the Langmuir equation and the maximum adsorption capacity was found to be 91.4 mg g-1. The presence of co-existing anions at higher concentrations significantly reduced the removal of Cr(VI) by chitosan. According to the presented results, it can be concluded that biopolymer chitosan has a great potential for application in the treatment of chromium contaminated wastewaters.","PeriodicalId":7216,"journal":{"name":"Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84353410","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}
Textile material is the biggest cost driver of the apparel industry, reaching up to 75 % of total production cost, so even minimal fabric savings directly affects the overall pro duction costs. Based on the data given in the work order in terms of quantities, sizes and colors, the cut order plan makes efforts to minimize the total production costs by developing an optimal cut order plan in terms of available quantities of material, machinery and labor. Marker has a direct impact on fabric consumption. The choice of the cut marker type depends on the type of garment, textile material structure and work order size. Understanding how to reduce consumption of textile materials, or in other words said increasing the utilization of cut markers is of great importance for technical preparation in the apparel industry, due to their important role in controlling material costs. The aim of this paper is to investigate the effect that the type and width of markers has on the consumption and utilization of textile materials.
{"title":"The influence of the type and width of the cut marker on the utilization of textile materials","authors":"Silvana Zhezhova, G. Demboski, Vineta Srebrenkoska, Sonja Jordeva, Longurova Golomeova Sashka","doi":"10.5937/savteh1902099z","DOIUrl":"https://doi.org/10.5937/savteh1902099z","url":null,"abstract":"Textile material is the biggest cost driver of the apparel industry, reaching up to 75 % of total production cost, so even minimal fabric savings directly affects the overall pro duction costs. Based on the data given in the work order in terms of quantities, sizes and colors, the cut order plan makes efforts to minimize the total production costs by developing an optimal cut order plan in terms of available quantities of material, machinery and labor. Marker has a direct impact on fabric consumption. The choice of the cut marker type depends on the type of garment, textile material structure and work order size. Understanding how to reduce consumption of textile materials, or in other words said increasing the utilization of cut markers is of great importance for technical preparation in the apparel industry, due to their important role in controlling material costs. The aim of this paper is to investigate the effect that the type and width of markers has on the consumption and utilization of textile materials.","PeriodicalId":7216,"journal":{"name":"Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76758796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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