Pub Date : 2023-11-22DOI: 10.3390/separations10120579
Julia Szabadi-Fuchs, J. Meyer, Achim Dittler
A current subject of research is the application of magnetic effects for the detachment of accumulated particles of fibrous collectors in gas particle separation. Initial studies have already shown the magnetically induced detachment behavior of a compact particle structure after a single deflection from a single fiber. In this study, the detachment behavior of particle structures with different morphologies from a single fiber is investigated as a function of the particle loading stage on the fiber, the external magnetic flux density, the inflow velocity and the number of regenerations of the fiber for a certain parameter range. Diffusive and more compact particle structures with non-magnetic properties are deposited on the magnetizable single fiber. By applying an external magnetic field, the fiber is magnetized and experiences a torsional moment. The deposited particle structures on the fiber are detached by the acceleration forces. The detachment of the particle structures is observed using a high-speed camera and the image sequences are analyzed. By determining the projection area before and after the fiber deflection, a degree of regeneration is calculated. With magnetic-induced regeneration, high degrees of regeneration close to 100% can be achieved. Repetitive fiber deflections improve the detachment of the particle structures. The magnetic-induced regeneration is suitable for applications where flow reversal is not possible and can be performed either online or offline. Due to the gentle regeneration, fewer emissions are produced on the clean gas side than, for example, with jet pulse cleaning. It makes it easier to achieve emission limits and simplifies product recovery.
{"title":"Experimental Investigations of the Detachment of Different Particle Structures from a Magnetizable Fiber in the Gas Phase","authors":"Julia Szabadi-Fuchs, J. Meyer, Achim Dittler","doi":"10.3390/separations10120579","DOIUrl":"https://doi.org/10.3390/separations10120579","url":null,"abstract":"A current subject of research is the application of magnetic effects for the detachment of accumulated particles of fibrous collectors in gas particle separation. Initial studies have already shown the magnetically induced detachment behavior of a compact particle structure after a single deflection from a single fiber. In this study, the detachment behavior of particle structures with different morphologies from a single fiber is investigated as a function of the particle loading stage on the fiber, the external magnetic flux density, the inflow velocity and the number of regenerations of the fiber for a certain parameter range. Diffusive and more compact particle structures with non-magnetic properties are deposited on the magnetizable single fiber. By applying an external magnetic field, the fiber is magnetized and experiences a torsional moment. The deposited particle structures on the fiber are detached by the acceleration forces. The detachment of the particle structures is observed using a high-speed camera and the image sequences are analyzed. By determining the projection area before and after the fiber deflection, a degree of regeneration is calculated. With magnetic-induced regeneration, high degrees of regeneration close to 100% can be achieved. Repetitive fiber deflections improve the detachment of the particle structures. The magnetic-induced regeneration is suitable for applications where flow reversal is not possible and can be performed either online or offline. Due to the gentle regeneration, fewer emissions are produced on the clean gas side than, for example, with jet pulse cleaning. It makes it easier to achieve emission limits and simplifies product recovery.","PeriodicalId":21833,"journal":{"name":"Separations","volume":"309 ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139247533","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 : 2023-11-20DOI: 10.3390/separations10110578
Satoshi Fukada, Ryosuke Sakai, Makoto Oya, K. Katayama
Selective H2 evolution and CO2 absorption in several ethanolamine aqueous solutions are comparatively investigated using a new electrolysis reactor. H2 bubbles are generated from a cathode in any ethanolamine electrolyte, and its experimental gas evolution rates are correlated by Faraday’s first rule. No or smaller amounts of CO2 and N2 bubbles than stoichiometric ones are generated on an anode through the reaction between hydroxide ions and ethanolamine ones. No CO or O2 is observed in the system exhaust, and most of the CO2, along with N2, is still absorbed in ethanolamine aqueous solutions with the addition of KOH and/or HCOOH under high pH conditions. Variations of the concentrations of coexisting ions dissolved in the electrolytes of mono- or tri-ethanolamine (MEA or TEA) and ethylenediamine (EDA) solutions with CO2 absorption are calculated using the equilibrium constants to relate the concentrations of solute ions. Electric resistivities of the ethanolamine aqueous solutions are correlated by the pH value and are analyzed in terms of equilibrium constants among the concentrations of coexisting ions. Conditions of the MEA electrolyte to achieve high-performance electrolysis is discussed for selective H2 generation.
利用新型电解反应器对几种乙醇胺水溶液中 H2 的选择性进化和 CO2 的吸收进行了比较研究。在任何乙醇胺电解质中，阴极都会产生 H2 气泡，其实验气体进化速率与法拉第第一定律相关。通过氢氧根离子和乙醇胺离子之间的反应，阳极上不会产生二氧化碳和二氧化氮气泡，或者产生的气泡数量少于定量气泡。在高 pH 条件下，加入 KOH 和/或 HCOOH 后，乙醇胺水溶液仍可吸收大部分 CO2 和 N2。利用平衡常数计算了溶质离子浓度与一乙醇胺或三乙醇胺（MEA 或 TEA）和乙二胺（EDA）溶液中溶解的共存离子浓度随二氧化碳吸收量的变化情况。乙醇胺水溶液的电阻值与 pH 值相关，并根据共存离子浓度之间的平衡常数进行分析。讨论了 MEA 电解质实现高性能电解的条件，以便选择性生成 H2。
{"title":"Selective H2 Evolution and CO2 Absorption in Electrolysis of Ethanolamine Aqueous Solutions","authors":"Satoshi Fukada, Ryosuke Sakai, Makoto Oya, K. Katayama","doi":"10.3390/separations10110578","DOIUrl":"https://doi.org/10.3390/separations10110578","url":null,"abstract":"Selective H2 evolution and CO2 absorption in several ethanolamine aqueous solutions are comparatively investigated using a new electrolysis reactor. H2 bubbles are generated from a cathode in any ethanolamine electrolyte, and its experimental gas evolution rates are correlated by Faraday’s first rule. No or smaller amounts of CO2 and N2 bubbles than stoichiometric ones are generated on an anode through the reaction between hydroxide ions and ethanolamine ones. No CO or O2 is observed in the system exhaust, and most of the CO2, along with N2, is still absorbed in ethanolamine aqueous solutions with the addition of KOH and/or HCOOH under high pH conditions. Variations of the concentrations of coexisting ions dissolved in the electrolytes of mono- or tri-ethanolamine (MEA or TEA) and ethylenediamine (EDA) solutions with CO2 absorption are calculated using the equilibrium constants to relate the concentrations of solute ions. Electric resistivities of the ethanolamine aqueous solutions are correlated by the pH value and are analyzed in terms of equilibrium constants among the concentrations of coexisting ions. Conditions of the MEA electrolyte to achieve high-performance electrolysis is discussed for selective H2 generation.","PeriodicalId":21833,"journal":{"name":"Separations","volume":"1 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2023-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139254888","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 : 2023-11-19DOI: 10.3390/separations10110576
E. Polledri, R. Mercadante, S. Fustinoni
Glyphosate-based herbicides are the most widely used pesticides in the world; however, the toxicity of glyphosate (GlyP) toward humans, especially its carcinogenicity, is controversial. The aim of this work was to validate a rapid assay for measuring GlyP and its metabolite aminomethylphosphonic acid (AMPA) in urine for human biomonitoring. The analytes were purified via solid-phase extraction in the presence of isotopically labeled internal standards. An LC-MS/MS assay was developed using a column with a novel hybrid stationary phase combined with anion exchange and hydrophilic interaction liquid chromatography. Detection and quantification were performed using negative electrospray ionization in a hybrid triple quadrupole/linear ion trap mass spectrometer. The retention times for AMPA and GlyP were 1.44 and 7.24 min, respectively. Calibration curves showed a linear dynamic range of up to 40 µg/L, inter- and intra-run precisions <7.5%, and accuracies within 10% of the theoretical concentrations. The limits of quantification were 0.1 µg/L and 0.5 µg/L for GlyP and AMPA, respectively. The matrix effect bias was controlled using internal standards. Successful participation in external quality assurance exercises strengthens the validity of the method. The assay was applied to the measurement of GlyP and AMPA in the urine of 9 urban residents, 26 rural residents, and 12 agricultural workers; while AMPA was mostly not quantifiable, the median GlyP values were 0.1 and 0.34 µg/L in rural residents and workers, respectively. The assay is useful to assess GlyP and AMPA in human urine following different exposure scenarios.
{"title":"Validation of a Liquid Chromatography Coupled to Mass Spectrometry Method for Glyphosate and Aminomethylphosphonic Acid in Urine for Human Biomonitoring Using Combined Hybrid Anion-Exchange and Hydrophilic Interaction Liquid Chromatography","authors":"E. Polledri, R. Mercadante, S. Fustinoni","doi":"10.3390/separations10110576","DOIUrl":"https://doi.org/10.3390/separations10110576","url":null,"abstract":"Glyphosate-based herbicides are the most widely used pesticides in the world; however, the toxicity of glyphosate (GlyP) toward humans, especially its carcinogenicity, is controversial. The aim of this work was to validate a rapid assay for measuring GlyP and its metabolite aminomethylphosphonic acid (AMPA) in urine for human biomonitoring. The analytes were purified via solid-phase extraction in the presence of isotopically labeled internal standards. An LC-MS/MS assay was developed using a column with a novel hybrid stationary phase combined with anion exchange and hydrophilic interaction liquid chromatography. Detection and quantification were performed using negative electrospray ionization in a hybrid triple quadrupole/linear ion trap mass spectrometer. The retention times for AMPA and GlyP were 1.44 and 7.24 min, respectively. Calibration curves showed a linear dynamic range of up to 40 µg/L, inter- and intra-run precisions <7.5%, and accuracies within 10% of the theoretical concentrations. The limits of quantification were 0.1 µg/L and 0.5 µg/L for GlyP and AMPA, respectively. The matrix effect bias was controlled using internal standards. Successful participation in external quality assurance exercises strengthens the validity of the method. The assay was applied to the measurement of GlyP and AMPA in the urine of 9 urban residents, 26 rural residents, and 12 agricultural workers; while AMPA was mostly not quantifiable, the median GlyP values were 0.1 and 0.34 µg/L in rural residents and workers, respectively. The assay is useful to assess GlyP and AMPA in human urine following different exposure scenarios.","PeriodicalId":21833,"journal":{"name":"Separations","volume":"29 3","pages":""},"PeriodicalIF":2.6,"publicationDate":"2023-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139260063","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 : 2023-11-19DOI: 10.3390/separations10110577
D. Alshora, M. Ibrahim, Abdelrahman Y. Sherif
The development of analytical procedures capable of simultaneous determination of two or more drugs is in crucial demand due to the availability of different formulations that are composed of different APIs. The presented study aimed to optimize and validate a simple, accurate, and sensitive UPLC analytical method for the simultaneous determination of thymoquinone (TQ) and Glibenclamide (GB) using response surface methodology, and apply this method in pharmaceutical formulations. A 32 full design of experiment was utilized to study the impacts of the independent parameters (acetonitrile ACN concentration, A; and column temperature, B) on the drugs’ analytical attributes (viz, retention time, peak area, and peak asymmetry, in addition to the resolution between TQ and GB peaks). The results revealed that the independent parameters exhibited highly significant (p < 0.05) antagonistic effects on retention times for TQ and GB peaks, in addition to the agnostic effect on GB peak symmetry (p-value = 0.001). Moreover, antagonistic impacts (p < 0.05) on the resolution between TQ and GB peaks were found for both independent factors (A and B). The statistical software suggested 46.86% of ACN (A) and 38.80 °C for column temperature (B) for optimum analytical responses. The optimized green method was discovered to be acceptable in terms of selectivity, precision, accuracy, robustness, sensitivity, and specificity. Moreover, the optimized simultaneous method was successfully able to determine the contents of TQ and GB in self-nanoemulsifying drug delivery (SNEDD) formulation, in which the results showed that GB and TQ content within the prepared formulations were 1.54 ± 0.023 and 3.62 ± 0.031 mg/gm, respectively. In conclusion, the developed assay was efficient and valid in analyzing TQ and GB simultaneously in bulk and self-nanoemulsifying drug delivery system (SNEDDs) formulations.
{"title":"Optimization and Validation of Sensitive UPLC-PDA Method for Simultaneous Determination of Thymoquinone and Glibenclamide in SNEDDs Formulations Using Response Surface Methodology","authors":"D. Alshora, M. Ibrahim, Abdelrahman Y. Sherif","doi":"10.3390/separations10110577","DOIUrl":"https://doi.org/10.3390/separations10110577","url":null,"abstract":"The development of analytical procedures capable of simultaneous determination of two or more drugs is in crucial demand due to the availability of different formulations that are composed of different APIs. The presented study aimed to optimize and validate a simple, accurate, and sensitive UPLC analytical method for the simultaneous determination of thymoquinone (TQ) and Glibenclamide (GB) using response surface methodology, and apply this method in pharmaceutical formulations. A 32 full design of experiment was utilized to study the impacts of the independent parameters (acetonitrile ACN concentration, A; and column temperature, B) on the drugs’ analytical attributes (viz, retention time, peak area, and peak asymmetry, in addition to the resolution between TQ and GB peaks). The results revealed that the independent parameters exhibited highly significant (p < 0.05) antagonistic effects on retention times for TQ and GB peaks, in addition to the agnostic effect on GB peak symmetry (p-value = 0.001). Moreover, antagonistic impacts (p < 0.05) on the resolution between TQ and GB peaks were found for both independent factors (A and B). The statistical software suggested 46.86% of ACN (A) and 38.80 °C for column temperature (B) for optimum analytical responses. The optimized green method was discovered to be acceptable in terms of selectivity, precision, accuracy, robustness, sensitivity, and specificity. Moreover, the optimized simultaneous method was successfully able to determine the contents of TQ and GB in self-nanoemulsifying drug delivery (SNEDD) formulation, in which the results showed that GB and TQ content within the prepared formulations were 1.54 ± 0.023 and 3.62 ± 0.031 mg/gm, respectively. In conclusion, the developed assay was efficient and valid in analyzing TQ and GB simultaneously in bulk and self-nanoemulsifying drug delivery system (SNEDDs) formulations.","PeriodicalId":21833,"journal":{"name":"Separations","volume":"52 4","pages":""},"PeriodicalIF":2.6,"publicationDate":"2023-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139260469","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 : 2023-11-18DOI: 10.3390/separations10110575
J. Ganzhorn, Y. R. Ratovonamana, Melina Rother, Peggy Giertz, Curswan A Andrews, Sabine Baumann, Yvonne E.-M. B. Bohr, P. Kappeler, B. K. Montero, Andreas Pommerening-Röser, U. Radespiel, S. J. Rakotondranary, Oliver Schülke, K. Steffens, Sandra Thorén, G. Timmermann, Irene Tomaschewski
Gums produced by trees after injuries are valuable food resources for several primate species. Yet, information on the chemical characteristics of gum is scant and inconsistent. We use gums consumed by lemurs (strepsirrhine primates of Madagascar) as an example to illustrate their possible nutritive and pharmaceutical properties. Exudates from 45 tree species of the dry forests of Madagascar contained 0.38–23.29% protein, 0.46–65.62% sugar, and 0.39–11.86 kJ/g of energy in dry matter. Exemplified by the lemur species Microcebus griseorufus, gum consumption increased with increasing sugar and energy content but was unrelated to protein. But lemurs also fed on gum with very low protein and energy content, suggesting that these exudates were consumed for other reasons. Disk diffusion tests with exudates from five out of 22 tree species consumed by lemurs showed antibacterial activity against Micrococcus spp. and/or Staphylococcus aureus. Exudates with antibacterial activity had lower protein, sugar, and energy contents than samples without antibacterial properties. GC-MS analyses revealed several components with antimicrobial effects that would have the potential for self-medication. This might explain the consumption of gum with very low nutritive value. Possible medicinal effects of tree exudates deserve further attention in view of their pharmaceutical applicability for animals and humans alike.
{"title":"Nutritional and Possible Pharmaceutical Aspects of Tree Exudates Eaten by Lemurs of Madagascar’s Dry Forests","authors":"J. Ganzhorn, Y. R. Ratovonamana, Melina Rother, Peggy Giertz, Curswan A Andrews, Sabine Baumann, Yvonne E.-M. B. Bohr, P. Kappeler, B. K. Montero, Andreas Pommerening-Röser, U. Radespiel, S. J. Rakotondranary, Oliver Schülke, K. Steffens, Sandra Thorén, G. Timmermann, Irene Tomaschewski","doi":"10.3390/separations10110575","DOIUrl":"https://doi.org/10.3390/separations10110575","url":null,"abstract":"Gums produced by trees after injuries are valuable food resources for several primate species. Yet, information on the chemical characteristics of gum is scant and inconsistent. We use gums consumed by lemurs (strepsirrhine primates of Madagascar) as an example to illustrate their possible nutritive and pharmaceutical properties. Exudates from 45 tree species of the dry forests of Madagascar contained 0.38–23.29% protein, 0.46–65.62% sugar, and 0.39–11.86 kJ/g of energy in dry matter. Exemplified by the lemur species Microcebus griseorufus, gum consumption increased with increasing sugar and energy content but was unrelated to protein. But lemurs also fed on gum with very low protein and energy content, suggesting that these exudates were consumed for other reasons. Disk diffusion tests with exudates from five out of 22 tree species consumed by lemurs showed antibacterial activity against Micrococcus spp. and/or Staphylococcus aureus. Exudates with antibacterial activity had lower protein, sugar, and energy contents than samples without antibacterial properties. GC-MS analyses revealed several components with antimicrobial effects that would have the potential for self-medication. This might explain the consumption of gum with very low nutritive value. Possible medicinal effects of tree exudates deserve further attention in view of their pharmaceutical applicability for animals and humans alike.","PeriodicalId":21833,"journal":{"name":"Separations","volume":"26 7","pages":""},"PeriodicalIF":2.6,"publicationDate":"2023-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139261899","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}
The Baima vanadium titanomagnetite deposit, located in the Panzhihua-Xichang (Panxi) metallogenic belt in China, is one of the super-large deposits in the region. The titanomagnetite upgrading process involves grinding the raw ore followed by magnetic separation. To determine the processing characteristics of the ore and assess the upgrading process, this study employs various methods and techniques, including the X-ray fluorescence spectrometer (XRF), chemical element analysis, the electron probe microanalyzer (EPMA), and the advanced mineral identification and characterization system (AMICS). The results show that the Fe grades in the upgraded raw ore, upgraded concentrate, and upgraded tailings are 55.68%, 57.89%, and 15.62%, respectively. After upgrading, the titanomagnetite content increased from 77.41% to 82.10%, and the Fe distribution in titanomagnetite also increased from 91.05% to 93.14%. In the upgraded raw ore, titanomagnetite particles followed a normal distribution, with 50.44% in the 38–74 μm range. In the upgraded concentrate, titanomagnetite was concentrated in the 19–38 μm range. Based on EPMA data, the theoretical Fe grade in titanomagnetite was calculated to be 65.08%, indicating the potential for further improvement through the upgrading process. This study elucidates the mineralogical characteristics during the vanadium titanomagnetite upgrading, providing a theoretical basis to further enhance the Fe recovery rate.
{"title":"Mineralogical Characteristics of Baima Vanadium Titanomagnetite during Magnetic Separation Upgrading","authors":"Xiang Zhong, Haoran Hu, Shuo Li, Jian Gao, Zhixin Shi, Fuxing Zhu","doi":"10.3390/separations10110574","DOIUrl":"https://doi.org/10.3390/separations10110574","url":null,"abstract":"The Baima vanadium titanomagnetite deposit, located in the Panzhihua-Xichang (Panxi) metallogenic belt in China, is one of the super-large deposits in the region. The titanomagnetite upgrading process involves grinding the raw ore followed by magnetic separation. To determine the processing characteristics of the ore and assess the upgrading process, this study employs various methods and techniques, including the X-ray fluorescence spectrometer (XRF), chemical element analysis, the electron probe microanalyzer (EPMA), and the advanced mineral identification and characterization system (AMICS). The results show that the Fe grades in the upgraded raw ore, upgraded concentrate, and upgraded tailings are 55.68%, 57.89%, and 15.62%, respectively. After upgrading, the titanomagnetite content increased from 77.41% to 82.10%, and the Fe distribution in titanomagnetite also increased from 91.05% to 93.14%. In the upgraded raw ore, titanomagnetite particles followed a normal distribution, with 50.44% in the 38–74 μm range. In the upgraded concentrate, titanomagnetite was concentrated in the 19–38 μm range. Based on EPMA data, the theoretical Fe grade in titanomagnetite was calculated to be 65.08%, indicating the potential for further improvement through the upgrading process. This study elucidates the mineralogical characteristics during the vanadium titanomagnetite upgrading, providing a theoretical basis to further enhance the Fe recovery rate.","PeriodicalId":21833,"journal":{"name":"Separations","volume":"25 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2023-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139262672","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 : 2023-11-16DOI: 10.3390/separations10110572
T. Kuballa, Katja H. Kaltenbach, J. Teipel, D. Lachenmeier
As early as 1946, Felix Bloch and Edward Mills Purcell detected nuclear magnetic resonance signals, earning themselves the Nobel Prize in 1952. The same year saw the launch of the first commercial nuclear magnetic resonance (NMR) spectrometer. Since then, NMR has experienced significant progress in various fields of application. While in the 1970s NMR spectroscopy was solely employed for determining the structure and purity of synthesis products in the chemical field, it gradually gained popularity in the medical field for the investigation and rendering of images of human organs. Since then, the technique has developed significantly in terms of stability, reproducibility, and sensitivity, thereby forming the foundation for high-resolution imaging, the automation or standardization of analytical procedures, and the application of chemometric methods, particularly in relation to identifying food adulteration. This review objectively assesses the current state of implementing liquid NMR in the food, cosmetics, and pharmaceutical industries. Liquid NMR has transitioned from a structural elucidation tool to a widely recognized, multi-analytical method that incorporates multivariate techniques. The illustrations and sources provided aim to enhance novice readers’ understanding of this topic.
{"title":"Liquid Nuclear Magnetic Resonance (NMR) Spectroscopy in Transition—From Structure Elucidation to Multi-Analysis Method","authors":"T. Kuballa, Katja H. Kaltenbach, J. Teipel, D. Lachenmeier","doi":"10.3390/separations10110572","DOIUrl":"https://doi.org/10.3390/separations10110572","url":null,"abstract":"As early as 1946, Felix Bloch and Edward Mills Purcell detected nuclear magnetic resonance signals, earning themselves the Nobel Prize in 1952. The same year saw the launch of the first commercial nuclear magnetic resonance (NMR) spectrometer. Since then, NMR has experienced significant progress in various fields of application. While in the 1970s NMR spectroscopy was solely employed for determining the structure and purity of synthesis products in the chemical field, it gradually gained popularity in the medical field for the investigation and rendering of images of human organs. Since then, the technique has developed significantly in terms of stability, reproducibility, and sensitivity, thereby forming the foundation for high-resolution imaging, the automation or standardization of analytical procedures, and the application of chemometric methods, particularly in relation to identifying food adulteration. This review objectively assesses the current state of implementing liquid NMR in the food, cosmetics, and pharmaceutical industries. Liquid NMR has transitioned from a structural elucidation tool to a widely recognized, multi-analytical method that incorporates multivariate techniques. The illustrations and sources provided aim to enhance novice readers’ understanding of this topic.","PeriodicalId":21833,"journal":{"name":"Separations","volume":"23 9","pages":""},"PeriodicalIF":2.6,"publicationDate":"2023-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139266985","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 : 2023-11-16DOI: 10.3390/separations10110571
Tianzhe Shi, Tao Liu, Ning Qiang, Jiao He, Zhaohai Li, Yiqi Cao, Xianbin Shi
In this study, the diffusion, separation, and buffering of volatile organic compounds emitted in a non-steady state on activated carbon were studied. Ethanol and xylene, which have large differences in adsorption capacity and diffusion rate, were selected as the representative target pollutants of volatile organic compounds. In this paper, activated carbon with a certain intake concentration and adsorption equilibrium was chosen as the research object. The buffering effect of pulse load was studied. The buffering effect and influencing factors were analyzed. The Bangham equation proved to be a more effective tool in describing the dynamic processes of ethanol and xylene adsorption on activated carbon, indicating that pore diffusion was the rate-determining step in the adsorption process. R3 emerged as a more suitable criterion for evaluating non-steady-state emissions. Factors such as pulse time and pulse multiplier were influenced by Empty Bed Contact Time (EBCT), which collaborated with EBCT to impact the buffering performance of activated carbon. An EBCT of 4 cm was identified as the optimal bed height, with R3 reaching 1.48. Non-polar VOCs with chemically symmetric structures exhibited slower mass transfer rates compared to polar VOCs, resulting in larger adsorption capacities on activated carbon and better buffering performance.
{"title":"Diffusion, Separation, and Buffering of Non-Steady-State VOCs Flow on Activated Carbon","authors":"Tianzhe Shi, Tao Liu, Ning Qiang, Jiao He, Zhaohai Li, Yiqi Cao, Xianbin Shi","doi":"10.3390/separations10110571","DOIUrl":"https://doi.org/10.3390/separations10110571","url":null,"abstract":"In this study, the diffusion, separation, and buffering of volatile organic compounds emitted in a non-steady state on activated carbon were studied. Ethanol and xylene, which have large differences in adsorption capacity and diffusion rate, were selected as the representative target pollutants of volatile organic compounds. In this paper, activated carbon with a certain intake concentration and adsorption equilibrium was chosen as the research object. The buffering effect of pulse load was studied. The buffering effect and influencing factors were analyzed. The Bangham equation proved to be a more effective tool in describing the dynamic processes of ethanol and xylene adsorption on activated carbon, indicating that pore diffusion was the rate-determining step in the adsorption process. R3 emerged as a more suitable criterion for evaluating non-steady-state emissions. Factors such as pulse time and pulse multiplier were influenced by Empty Bed Contact Time (EBCT), which collaborated with EBCT to impact the buffering performance of activated carbon. An EBCT of 4 cm was identified as the optimal bed height, with R3 reaching 1.48. Non-polar VOCs with chemically symmetric structures exhibited slower mass transfer rates compared to polar VOCs, resulting in larger adsorption capacities on activated carbon and better buffering performance.","PeriodicalId":21833,"journal":{"name":"Separations","volume":"14 3","pages":""},"PeriodicalIF":2.6,"publicationDate":"2023-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139270252","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 : 2023-11-15DOI: 10.3390/separations10110570
Hanan H. Youssef, S. A. Younis, E. M. El‐Fawal, H. Ali, Y. M. Moustafa, Gehad G. Mohamed
This work investigates the potential synthesis of cost-effective polyaluminum chloride (PACl) coagulant from waste household aluminum foil and utilization for treating petroleum wastewater (PWW), especially dissolved organic compounds (DOC, like octanol–water mixture) and nonsettleable suspended (NSS-kaolin) mineral particles. Based on the Standard Practice for Coagulation–Flocculation Jar Test, the efficiency of PACl for DOC and NSS removal was evaluated in relation to the effects of the operational parameters. The results demonstrated that the as-prepared PACl has an amorphous morphology with a Keggin-type e-Al13 molecular structure {Na[AlO4(OH)24(H2O)]·xH2O and good thermal stability up to 278 °C. PACl coagulant also exhibited a higher efficiency for NSS removal than DOC by around 1.5- to 1.9-fold under broad pH (5–7), while a higher acidic/alkaline pH disrupts the sweep floc formation. An increased PACl dosage (over 25 mg/L) also caused a decrease in the coagulation efficiency by 11.7% due to Al species’ transformation and pH depression (from 6.8 to 4.9) via increased PACl hydrolysis. With a fast rotating speed of 280 rpm for 2 min, the minimum dose of PACl (10–25 mg/L) can maximize the removal efficiency of NSS (~98%) and DOC (~69%) at pH 6.5 ± 0.5 and 35 °C after 30 min of settling time. Treating actual saline PWW samples (salinity up to 187.7 g/L) also verified the high efficacy of PACl coagulation performance in reducing the turbidity and dissolved hydrocarbons by more than 75.5% and 67.7%, respectively. These findings verify the techno-economic feasibility of the as-prepared PACl coagulant in treating PWW treatment at different salinity levels.
{"title":"Synthesis of Polyaluminum Chloride Coagulant from Waste Aluminum Foil and Utilization in Petroleum Wastewater Treatment","authors":"Hanan H. Youssef, S. A. Younis, E. M. El‐Fawal, H. Ali, Y. M. Moustafa, Gehad G. Mohamed","doi":"10.3390/separations10110570","DOIUrl":"https://doi.org/10.3390/separations10110570","url":null,"abstract":"This work investigates the potential synthesis of cost-effective polyaluminum chloride (PACl) coagulant from waste household aluminum foil and utilization for treating petroleum wastewater (PWW), especially dissolved organic compounds (DOC, like octanol–water mixture) and nonsettleable suspended (NSS-kaolin) mineral particles. Based on the Standard Practice for Coagulation–Flocculation Jar Test, the efficiency of PACl for DOC and NSS removal was evaluated in relation to the effects of the operational parameters. The results demonstrated that the as-prepared PACl has an amorphous morphology with a Keggin-type e-Al13 molecular structure {Na[AlO4(OH)24(H2O)]·xH2O and good thermal stability up to 278 °C. PACl coagulant also exhibited a higher efficiency for NSS removal than DOC by around 1.5- to 1.9-fold under broad pH (5–7), while a higher acidic/alkaline pH disrupts the sweep floc formation. An increased PACl dosage (over 25 mg/L) also caused a decrease in the coagulation efficiency by 11.7% due to Al species’ transformation and pH depression (from 6.8 to 4.9) via increased PACl hydrolysis. With a fast rotating speed of 280 rpm for 2 min, the minimum dose of PACl (10–25 mg/L) can maximize the removal efficiency of NSS (~98%) and DOC (~69%) at pH 6.5 ± 0.5 and 35 °C after 30 min of settling time. Treating actual saline PWW samples (salinity up to 187.7 g/L) also verified the high efficacy of PACl coagulation performance in reducing the turbidity and dissolved hydrocarbons by more than 75.5% and 67.7%, respectively. These findings verify the techno-economic feasibility of the as-prepared PACl coagulant in treating PWW treatment at different salinity levels.","PeriodicalId":21833,"journal":{"name":"Separations","volume":"9 2","pages":""},"PeriodicalIF":2.6,"publicationDate":"2023-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139274493","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 : 2023-11-15DOI: 10.3390/separations10110569
Bao Wang, Shaotong Feng, Caihua Wang, Xiaoyan Liu, Lei Chen, D. Yan
Flexible and effective methods for oil–water separation are crucial for reducing pollutant emissions and safeguarding water and fuel resources. In recent years, there has been growing interest in fundamental research and engineering applications related to water and fuel purification, especially oil–water separation. To date, filter materials with special wetting characteristics have been widely used in oil–water separation. Nanostructured materials are one of the most attractive candidates for next-generation oil–water separation. This review systematically summarizes the mechanisms and current status of oil–water separation using nanostructured materials. Basically, this can be achieved by using nanostructured materials with specific wettability and nanostructures. Here, we provide a detailed discussion of two general approaches and their filtration mechanisms: (1) the selective filtration technique, based on specific surface wettability, which allows only oil or water to penetrate while blocking impurities; (2) the absorption technique, employing porous sponges, fibers, or aerogels, which selectively absorbs impure oil or water droplets. Furthermore, the main failure modes are discussed in this review. The purposes of this article are: (1) to summarize the methods of oil–water separation by nanotechnology; (2) to raise the level of environmental protection consciousness of water pollution by using nanotechnology; (3) to tease out the features of different approaches and provide a pivotal theoretical basis to optimize the performance of filtering materials. Several approaches for oil and water separation are compared. Furthermore, the principle and application scope of each method are introduced.
{"title":"Nanostructure-Based Oil–Water Separation: Mechanism and Status","authors":"Bao Wang, Shaotong Feng, Caihua Wang, Xiaoyan Liu, Lei Chen, D. Yan","doi":"10.3390/separations10110569","DOIUrl":"https://doi.org/10.3390/separations10110569","url":null,"abstract":"Flexible and effective methods for oil–water separation are crucial for reducing pollutant emissions and safeguarding water and fuel resources. In recent years, there has been growing interest in fundamental research and engineering applications related to water and fuel purification, especially oil–water separation. To date, filter materials with special wetting characteristics have been widely used in oil–water separation. Nanostructured materials are one of the most attractive candidates for next-generation oil–water separation. This review systematically summarizes the mechanisms and current status of oil–water separation using nanostructured materials. Basically, this can be achieved by using nanostructured materials with specific wettability and nanostructures. Here, we provide a detailed discussion of two general approaches and their filtration mechanisms: (1) the selective filtration technique, based on specific surface wettability, which allows only oil or water to penetrate while blocking impurities; (2) the absorption technique, employing porous sponges, fibers, or aerogels, which selectively absorbs impure oil or water droplets. Furthermore, the main failure modes are discussed in this review. The purposes of this article are: (1) to summarize the methods of oil–water separation by nanotechnology; (2) to raise the level of environmental protection consciousness of water pollution by using nanotechnology; (3) to tease out the features of different approaches and provide a pivotal theoretical basis to optimize the performance of filtering materials. Several approaches for oil and water separation are compared. Furthermore, the principle and application scope of each method are introduced.","PeriodicalId":21833,"journal":{"name":"Separations","volume":"55 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2023-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139276142","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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