Pub Date : 2023-09-02DOI: 10.1080/01496395.2023.2250550
Guohua Li, Aimin Zhang, Xianjin Qi, Guizhi Yan, Gang Zhi
ABSTRACTIn the process of removing arsenic in an arsenic-containing aqueous solution, a large amount of harmful arsenic-containing waste is usually discharged. In this paper, a recyclable and environmentally friendly method of removing arsenic with Al/Ti-supported chitosan (ATC) was proposed. The results show that ATC has the best adsorption effect on arsenic at pH 8 at room temperature. In addition, the ratio of Al and Ti to chitosan (CB) affects the adsorption effect of ATC on arsenic. When Al: Ti: CB is 1:1:10, the removal rate of arsenic is as high as 99%. ATC can rapidly adsorb arsenic within 30 min. The adsorption kinetics shows that the adsorption of ATC on arsenic follows the joint action of physical adsorption and chemical precipitation. The adsorption isotherm shows that the adsorption process is multilayer adsorption. Finally, ATC has good recycling ability and is an efficient arsenic-removing agent in the treatment of arsenic-containing aqueous solutions. It shows great potential in the remediation of heavy metal-containing aqueous solutions.KEYWORDS: Arsenicaqueous solutionchitosanadsorptiondynamics Highlights The formation of Al/Ti loaded-chitosan is simple and economical.Effective removal of arsenic from high-arsenic aqueous solution using Al/Ti loaded-chitosan.Al/Ti loaded-chitosan can be regenerated and continuously useDisclosure statementNo potential conflict of interest was reported by the authorStatement of noveltyIn the process of removing arsenic from arsenic-bearing aqueous solution, a large amount of hazardous arsenic-bearing waste is usually discharged. We propose a recyclable and environmentally friendly method for the efficient removal of arsenic using Al/Ti loaded-chitosan (ATC). The results show 99% of arsenic could be removed from arsenic-bearing aqueous solution and reduce the arsenic concentration from 200 mg/L to 10 μg/L using ATC at room temperature. The highest arsenic removal capacity of ATC reaches 45 mg/g due to the superior arsenic adsorption. ATC acts as a highly effective arsenic remover for the disposal of arsenic-bearing aqueous solution. It shows great potential for the remediation of aqueous solution containing heavy metals.Supplementary materialSupplemental data for this article can be accessed online at https://doi.org/10.1080/01496395.2023.2250550Additional informationFundingThis project is supported by the National Natural Science Foundation of China (Grant No. 52160011), the Yunnan Province Ten Thousand Talents Plan Young Talents Training Fund (No. KKRD201952029), the University-Enterprise Cooperation Project of Kunming University of Science and Technology (No. KKZ4201552002).
{"title":"Arsenic removal from aqueous solution by chitosan loaded with Al/Ti elements","authors":"Guohua Li, Aimin Zhang, Xianjin Qi, Guizhi Yan, Gang Zhi","doi":"10.1080/01496395.2023.2250550","DOIUrl":"https://doi.org/10.1080/01496395.2023.2250550","url":null,"abstract":"ABSTRACTIn the process of removing arsenic in an arsenic-containing aqueous solution, a large amount of harmful arsenic-containing waste is usually discharged. In this paper, a recyclable and environmentally friendly method of removing arsenic with Al/Ti-supported chitosan (ATC) was proposed. The results show that ATC has the best adsorption effect on arsenic at pH 8 at room temperature. In addition, the ratio of Al and Ti to chitosan (CB) affects the adsorption effect of ATC on arsenic. When Al: Ti: CB is 1:1:10, the removal rate of arsenic is as high as 99%. ATC can rapidly adsorb arsenic within 30 min. The adsorption kinetics shows that the adsorption of ATC on arsenic follows the joint action of physical adsorption and chemical precipitation. The adsorption isotherm shows that the adsorption process is multilayer adsorption. Finally, ATC has good recycling ability and is an efficient arsenic-removing agent in the treatment of arsenic-containing aqueous solutions. It shows great potential in the remediation of heavy metal-containing aqueous solutions.KEYWORDS: Arsenicaqueous solutionchitosanadsorptiondynamics Highlights The formation of Al/Ti loaded-chitosan is simple and economical.Effective removal of arsenic from high-arsenic aqueous solution using Al/Ti loaded-chitosan.Al/Ti loaded-chitosan can be regenerated and continuously useDisclosure statementNo potential conflict of interest was reported by the authorStatement of noveltyIn the process of removing arsenic from arsenic-bearing aqueous solution, a large amount of hazardous arsenic-bearing waste is usually discharged. We propose a recyclable and environmentally friendly method for the efficient removal of arsenic using Al/Ti loaded-chitosan (ATC). The results show 99% of arsenic could be removed from arsenic-bearing aqueous solution and reduce the arsenic concentration from 200 mg/L to 10 μg/L using ATC at room temperature. The highest arsenic removal capacity of ATC reaches 45 mg/g due to the superior arsenic adsorption. ATC acts as a highly effective arsenic remover for the disposal of arsenic-bearing aqueous solution. It shows great potential for the remediation of aqueous solution containing heavy metals.Supplementary materialSupplemental data for this article can be accessed online at https://doi.org/10.1080/01496395.2023.2250550Additional informationFundingThis project is supported by the National Natural Science Foundation of China (Grant No. 52160011), the Yunnan Province Ten Thousand Talents Plan Young Talents Training Fund (No. KKRD201952029), the University-Enterprise Cooperation Project of Kunming University of Science and Technology (No. KKZ4201552002).","PeriodicalId":21680,"journal":{"name":"Separation Science and Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134968538","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 : 2023-09-02DOI: 10.1080/01496395.2023.2250549
Maria de Lourdes Mendoza, Jose Delgado, Pablo Villa, Bernardo Mora, Haci Baykara
ABSTRACTSelenium is found in natural waters of developing countries. The present study refers to Se (IV) adsorption onto an Ecuadorian natural zeolite, activated at 225°C. Its physicochemical characterization included particle size analysis, XRD, SEM-EDX, and FTIR. After selenium adsorption, the FTIR spectra denoted the presence of moved bands and new peaks, probably corresponding to new metal bond vibrations. Batch experiments were carried out at 26°C, for 2 h, at adsorbate doses within 0.01–50 mg L−1, bringing about a removal percentage in the range of 57−90%. Eventually, Se (IV) adsorption was performed at a pH of 7.5, resembling realistic well-water matrix conditions. Zeolite accomplished a maximum Se adsorption capacity of 53 mg g−1 zeolite, corresponding to roughly 90% of Se removal. The results obtained upon constant flow mode were analyzed with various kinetic models, appearing Thomas and BDST models to fit better. The highest Se removal percentage on typical well waters leaves a Se value lower than the permissible levels. Thus, natural zeolites offer an economic and competitive alternative for Se (IV) removal, especially from groundwater and industrial wastewater in developing countries.KEYWORDS: Adsorption bed columnsadsorption isotherm modelsadsorption selenium removalbreakthrough curvesnatural zeolites Highlights Batch experiments with doses resembling groundwater and industrial waters brought about 57% 90% Se removal.Se (IV) adsorption could be successfully attained at pH 7.5, thus avoiding chemicals usage.Natural mordenite-type zeolite accomplished a maximum Se adsorption capacity of 53 µg L–1 zeolite.Kinetic studies from Se adsorption on column fit well Thomas and BDST models.The highest Se removal percentage at groundwater levels leaves a Se value lower than permissible levels.Disclosure statementNo potential conflict of interest was reported by the author(s).Data availability statementThe data that support the findings of this study are available on request from the corresponding author.Statement of noveltyThe present study deals with the treatment of water contaminated with selenium, a typical nonmetal in groundwaters generated from industrial activities. The metal has been proposed to be removed using the adsorption principle onto a natural mordenite-type zeolite, on which scarce studies are reported for selenium removal, unlike artificial ones. In a particular way, the study is outstanding because it also compares Se adsorption on natural and artificial mordenite and intentionally declines the most suitable adsorption conditions to favor others which still results in practical, i.e., pH adjustment avoidance, consequently avoiding chemical usage. Upon these conditions, batch and column trials were performed. Finally, the strategy brings economic and environmental benefits such as reducing costs, especially for developing countries, where inexpensive adsorption technologies are not common.Supplementary materialSupplemental data
{"title":"The potential of a natural Ecuadorian mordenite-type zeolite for batch and column selenium removal","authors":"Maria de Lourdes Mendoza, Jose Delgado, Pablo Villa, Bernardo Mora, Haci Baykara","doi":"10.1080/01496395.2023.2250549","DOIUrl":"https://doi.org/10.1080/01496395.2023.2250549","url":null,"abstract":"ABSTRACTSelenium is found in natural waters of developing countries. The present study refers to Se (IV) adsorption onto an Ecuadorian natural zeolite, activated at 225°C. Its physicochemical characterization included particle size analysis, XRD, SEM-EDX, and FTIR. After selenium adsorption, the FTIR spectra denoted the presence of moved bands and new peaks, probably corresponding to new metal bond vibrations. Batch experiments were carried out at 26°C, for 2 h, at adsorbate doses within 0.01–50 mg L−1, bringing about a removal percentage in the range of 57−90%. Eventually, Se (IV) adsorption was performed at a pH of 7.5, resembling realistic well-water matrix conditions. Zeolite accomplished a maximum Se adsorption capacity of 53 mg g−1 zeolite, corresponding to roughly 90% of Se removal. The results obtained upon constant flow mode were analyzed with various kinetic models, appearing Thomas and BDST models to fit better. The highest Se removal percentage on typical well waters leaves a Se value lower than the permissible levels. Thus, natural zeolites offer an economic and competitive alternative for Se (IV) removal, especially from groundwater and industrial wastewater in developing countries.KEYWORDS: Adsorption bed columnsadsorption isotherm modelsadsorption selenium removalbreakthrough curvesnatural zeolites Highlights Batch experiments with doses resembling groundwater and industrial waters brought about 57% 90% Se removal.Se (IV) adsorption could be successfully attained at pH 7.5, thus avoiding chemicals usage.Natural mordenite-type zeolite accomplished a maximum Se adsorption capacity of 53 µg L–1 zeolite.Kinetic studies from Se adsorption on column fit well Thomas and BDST models.The highest Se removal percentage at groundwater levels leaves a Se value lower than permissible levels.Disclosure statementNo potential conflict of interest was reported by the author(s).Data availability statementThe data that support the findings of this study are available on request from the corresponding author.Statement of noveltyThe present study deals with the treatment of water contaminated with selenium, a typical nonmetal in groundwaters generated from industrial activities. The metal has been proposed to be removed using the adsorption principle onto a natural mordenite-type zeolite, on which scarce studies are reported for selenium removal, unlike artificial ones. In a particular way, the study is outstanding because it also compares Se adsorption on natural and artificial mordenite and intentionally declines the most suitable adsorption conditions to favor others which still results in practical, i.e., pH adjustment avoidance, consequently avoiding chemical usage. Upon these conditions, batch and column trials were performed. Finally, the strategy brings economic and environmental benefits such as reducing costs, especially for developing countries, where inexpensive adsorption technologies are not common.Supplementary materialSupplemental data ","PeriodicalId":21680,"journal":{"name":"Separation Science and Technology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134968662","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 : 2023-09-02DOI: 10.1080/01496395.2023.2255737
Hao Wang, Liwei Zheng, Bo Yuan, Shiwei Guo, Chungang Yuan
ABSTRACT Polyethyleneimine (PEI) based positive charge nanofiltration (NF) membranes have unique advantages in the removal of heavy metals. The regulation mechanism of the interlayer when PEI was used as monomer was still not clear. In this study, a PVA-based interlayer was constructed on the origin PES sublayer to tailor the interfacial polymerization in PEI systems. It was proved that the PVA interlayer can further elevate the PWP and rejections of heavy metals. Moreover, the absorption effect of interlayers could contribute to better removal of heavy metals. More negative charges of interlayer could result in a more enough and uniform absorption of PEI monomer as well as a slower diffusion rate of PEI monomer during the interfacial polymerization reaction, thus forming a loose top surface but dense sub-separating layer. This study provides new insight into the effect of interlayer on the performance of PEI-based nanofiltration membrane.
{"title":"How polyvinyl alcohol-based interlayers affect the performance of polyamide nanofiltration membranes prepared by polyethyleneimine","authors":"Hao Wang, Liwei Zheng, Bo Yuan, Shiwei Guo, Chungang Yuan","doi":"10.1080/01496395.2023.2255737","DOIUrl":"https://doi.org/10.1080/01496395.2023.2255737","url":null,"abstract":"ABSTRACT Polyethyleneimine (PEI) based positive charge nanofiltration (NF) membranes have unique advantages in the removal of heavy metals. The regulation mechanism of the interlayer when PEI was used as monomer was still not clear. In this study, a PVA-based interlayer was constructed on the origin PES sublayer to tailor the interfacial polymerization in PEI systems. It was proved that the PVA interlayer can further elevate the PWP and rejections of heavy metals. Moreover, the absorption effect of interlayers could contribute to better removal of heavy metals. More negative charges of interlayer could result in a more enough and uniform absorption of PEI monomer as well as a slower diffusion rate of PEI monomer during the interfacial polymerization reaction, thus forming a loose top surface but dense sub-separating layer. This study provides new insight into the effect of interlayer on the performance of PEI-based nanofiltration membrane.","PeriodicalId":21680,"journal":{"name":"Separation Science and Technology","volume":"43 1","pages":"2369 - 2382"},"PeriodicalIF":2.8,"publicationDate":"2023-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80968513","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 : 2023-09-02DOI: 10.1080/01496395.2023.2252985
Bahig M. Atia, M. Cheira, M. A. Hassanin, Hassan S. El-Gendy, M. E. Elawady, Hazem K.A. Sarhan, H. Radwan, Sameh H. Negm, M. Gado
ABSTRACT An innovative promising Gallic acid anchored poly vinyl alcohol via ethyl carbamate linker (PVA-EC-GA), was functionalized to extract boron from a tourmaline ore sample from Sikait area in South Eastern Desert of Egypt, which assaying 10.45% boron oxide. Specifications for PVA-EC-GA composite were accomplished by employing a variety of methods including XPS, FT-IR, EDX, BET, 1 H-NMR, TGA, 13C-NMR and GC-MS analyses, which assure an equitable prepare of PVA-EC-GA. Investigational measurements, namely: pH, agitation time, initial concentration of boron, composite dose, co-ions, temp. and agents of eluting, have been improved. At 25°C, pH 10, 20 min agitation and 0.0092 mol/L boron ions, PVA-EC-GA composite has an extreme uptake capacity of 43.75 mg per gram which is equivalent to 175 mg/L boron ions. From the isotherm modeling, Langmuir’s quite fitting the practical data. Conferring to kinetic modeling, pseudo-second order kinetic model well predicted the kinetics of boron ions adsorption by PVA-EC-GA giving a theoretical retention capacity of 43.86 mg/g. Thermodynamic prospects expose that the adsorption process was expected as an exothermic, spontaneous, and preferable adsorption at low temp. Boron ions can be eluted from the loaded composite, by 0.5 M H2SO4 with a 97% effectiveness
{"title":"Enhanced boron recovery by a new synthesized polyvinyl alcohol anchored gallic acid moiety via ethyl carbamate linker","authors":"Bahig M. Atia, M. Cheira, M. A. Hassanin, Hassan S. El-Gendy, M. E. Elawady, Hazem K.A. Sarhan, H. Radwan, Sameh H. Negm, M. Gado","doi":"10.1080/01496395.2023.2252985","DOIUrl":"https://doi.org/10.1080/01496395.2023.2252985","url":null,"abstract":"ABSTRACT An innovative promising Gallic acid anchored poly vinyl alcohol via ethyl carbamate linker (PVA-EC-GA), was functionalized to extract boron from a tourmaline ore sample from Sikait area in South Eastern Desert of Egypt, which assaying 10.45% boron oxide. Specifications for PVA-EC-GA composite were accomplished by employing a variety of methods including XPS, FT-IR, EDX, BET, 1 H-NMR, TGA, 13C-NMR and GC-MS analyses, which assure an equitable prepare of PVA-EC-GA. Investigational measurements, namely: pH, agitation time, initial concentration of boron, composite dose, co-ions, temp. and agents of eluting, have been improved. At 25°C, pH 10, 20 min agitation and 0.0092 mol/L boron ions, PVA-EC-GA composite has an extreme uptake capacity of 43.75 mg per gram which is equivalent to 175 mg/L boron ions. From the isotherm modeling, Langmuir’s quite fitting the practical data. Conferring to kinetic modeling, pseudo-second order kinetic model well predicted the kinetics of boron ions adsorption by PVA-EC-GA giving a theoretical retention capacity of 43.86 mg/g. Thermodynamic prospects expose that the adsorption process was expected as an exothermic, spontaneous, and preferable adsorption at low temp. Boron ions can be eluted from the loaded composite, by 0.5 M H2SO4 with a 97% effectiveness","PeriodicalId":21680,"journal":{"name":"Separation Science and Technology","volume":"30 1","pages":"2307 - 2330"},"PeriodicalIF":2.8,"publicationDate":"2023-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91321327","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 : 2023-08-29DOI: 10.1080/01496395.2023.2248650
Rutuja Bhoje, A. Ghosh, Parag R. Nemade
{"title":"Functionalized graphene-based material as a nanofiller for high-performance thin film composite seawater reverse osmosis membrane","authors":"Rutuja Bhoje, A. Ghosh, Parag R. Nemade","doi":"10.1080/01496395.2023.2248650","DOIUrl":"https://doi.org/10.1080/01496395.2023.2248650","url":null,"abstract":"","PeriodicalId":21680,"journal":{"name":"Separation Science and Technology","volume":"9 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73496454","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 : 2023-08-28DOI: 10.1080/01496395.2023.2252585
Hassan Akbar, Alishba Zulfiqar, Hijab Imran, A. Raza, Faiza Anjum, Syeda Tehreem Iqbal, Ashfaq Ahmad, Asghar Ali
ABSTRACT In this study, the degradation of MO (Methyl orange) dye using visible light irradiation and Ag2Se photo-catalyst was investigated. The Ag2Se photo-catalyst was synthesized via a wet chemical technique and characterized by using X-ray diffraction (XRD) for structural analysis, scanning electron microscopy (SEM) for surface morphology, transmission electron microscopy (TEM) for inner structure, Raman and UV-Vis spectroscopy for the study of its optical properties. The results showed that the Ag2Se photo-catalyst has a well-defined cubic crystal structure with a typical particle size of 50 to 76.5 nm. The UV-Vis absorption spectrum of the Ag2Se photo-catalyst revealed a strong absorption in the visible light region, indicating its potential as visible light photo-catalyst. The photocatalytic degradation of MO dye was carried out under visible light irradiation using the synthesized Ag2Se photo-catalyst. The results showed that the degradation efficiency of MO dye reached 95% after 150 min of irradiation. The degradation of MO dye was attributed to the generation of reactive oxygen species (ROS) and the formation of Ag nanoclusters on the surface of the Ag2Se photo-catalyst. The stability of the Ag2Se photo-catalyst was also examined, and the results exhibited that the photo-catalyst was stable and could be reused for subsequent photocatalytic degradation experiments. The Ag2Se photo-catalyst showed an outstanding photo catalytic activity for the degradation of MO dye underneath visible light irradiation. The study proposes that the Ag2Se photo-catalyst can be used for the treatment of wastewater containing organic pollutants.
{"title":"Investigating the effects of sacrificial agents on MO dye degradation with Ag2Se nanocomposites via chemical wet method using visible light irradiation","authors":"Hassan Akbar, Alishba Zulfiqar, Hijab Imran, A. Raza, Faiza Anjum, Syeda Tehreem Iqbal, Ashfaq Ahmad, Asghar Ali","doi":"10.1080/01496395.2023.2252585","DOIUrl":"https://doi.org/10.1080/01496395.2023.2252585","url":null,"abstract":"ABSTRACT In this study, the degradation of MO (Methyl orange) dye using visible light irradiation and Ag2Se photo-catalyst was investigated. The Ag2Se photo-catalyst was synthesized via a wet chemical technique and characterized by using X-ray diffraction (XRD) for structural analysis, scanning electron microscopy (SEM) for surface morphology, transmission electron microscopy (TEM) for inner structure, Raman and UV-Vis spectroscopy for the study of its optical properties. The results showed that the Ag2Se photo-catalyst has a well-defined cubic crystal structure with a typical particle size of 50 to 76.5 nm. The UV-Vis absorption spectrum of the Ag2Se photo-catalyst revealed a strong absorption in the visible light region, indicating its potential as visible light photo-catalyst. The photocatalytic degradation of MO dye was carried out under visible light irradiation using the synthesized Ag2Se photo-catalyst. The results showed that the degradation efficiency of MO dye reached 95% after 150 min of irradiation. The degradation of MO dye was attributed to the generation of reactive oxygen species (ROS) and the formation of Ag nanoclusters on the surface of the Ag2Se photo-catalyst. The stability of the Ag2Se photo-catalyst was also examined, and the results exhibited that the photo-catalyst was stable and could be reused for subsequent photocatalytic degradation experiments. The Ag2Se photo-catalyst showed an outstanding photo catalytic activity for the degradation of MO dye underneath visible light irradiation. The study proposes that the Ag2Se photo-catalyst can be used for the treatment of wastewater containing organic pollutants.","PeriodicalId":21680,"journal":{"name":"Separation Science and Technology","volume":"26 1","pages":"2383 - 2393"},"PeriodicalIF":2.8,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86187273","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}
ABSTRACT One common application of pressure swing adsorption technology is medical oxygen concentrator (MOC) which directly produces ~ 94% O2 from air. The operating condition determines the separation efficiency of MOC and is varied with practical requirements. A better understanding of performance, mass and heat transfer inside adsorption bed at wide operating conditions is of great importance. The impacts of key operating parameters on the performances, the concentration and temperature distributions of MOC have been numerically investigated. The numerical results demonstrate that high comprehensive performances are achieved at an optimal condition with combination of adsorption pressure, product and feed flowrate and feed temperature. As adsorption pressure increases, the front of gas concentration and temperature becomes sharp, which effectively benefits for improving the performance. It is nearly identical shapes of nitrogen concentration and gas temperature profiles after adsorption and the profiles are pushed forward near production end with increasing of product flowrates and decreasing of feed flowrates. The increasing of feed temperature is beneficial to improve the performance. However, the adverse mass transfer and thermal effects are dominant at very high pressures, flowrates and temperatures conditions and this variation increases the unit power of MOC.
{"title":"Comprehensive performance and numerical analysis of pressure swing adsorption process-based medical oxygen concentrators under various operating conditions","authors":"Xianqiang Zhu, Yuan Sun, Liang Dong, Xianhang Sun, Shuhui Li, Hong Chen, Junyu Zhang, Jinju Chen","doi":"10.1080/01496395.2023.2245132","DOIUrl":"https://doi.org/10.1080/01496395.2023.2245132","url":null,"abstract":"ABSTRACT One common application of pressure swing adsorption technology is medical oxygen concentrator (MOC) which directly produces ~ 94% O2 from air. The operating condition determines the separation efficiency of MOC and is varied with practical requirements. A better understanding of performance, mass and heat transfer inside adsorption bed at wide operating conditions is of great importance. The impacts of key operating parameters on the performances, the concentration and temperature distributions of MOC have been numerically investigated. The numerical results demonstrate that high comprehensive performances are achieved at an optimal condition with combination of adsorption pressure, product and feed flowrate and feed temperature. As adsorption pressure increases, the front of gas concentration and temperature becomes sharp, which effectively benefits for improving the performance. It is nearly identical shapes of nitrogen concentration and gas temperature profiles after adsorption and the profiles are pushed forward near production end with increasing of product flowrates and decreasing of feed flowrates. The increasing of feed temperature is beneficial to improve the performance. However, the adverse mass transfer and thermal effects are dominant at very high pressures, flowrates and temperatures conditions and this variation increases the unit power of MOC.","PeriodicalId":21680,"journal":{"name":"Separation Science and Technology","volume":"30 1","pages":"2241 - 2253"},"PeriodicalIF":2.8,"publicationDate":"2023-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86070014","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 : 2023-08-17DOI: 10.1080/01496395.2023.2248368
Chengbing Yu, Zhenhua Zheng, Qingxuan Wang, Liyuan Zhang, Zhegnsheng Ma
ABSTRACT In this study, the influences of sulfonate dye structure on the extraction rate, the reaction mechanism, and the complex ratio were studied. The parent structure and the number of sulfonic acid groups of sulfonate dyes have a great effect on extraction performance, whilst the molecular weight has a small effect on extraction performance. The results indicate that the extraction rate of azo dyes remains above 80% at the aqueous-organic phase ratio of 7:1, but the extraction rate of two anthraquinone dyes decreases to 54.9% and 34.9%, respectively; and the fewer the number of sulfonic acid groups of the dye, the better the extraction performance under the condition of insufficient extractant, the extraction rate of Direct Grey D and Acid Red M is over 82%. A complete set of methods for determining the ratio of the extractant and the dye was determined using the distribution coefficient method. The interaction between Telon Yellow 4 R and trioctylamine is ionic association and hydrogen bonding association, and the complex ratio between the dye and the extractant is about 2:1. In summary, dye structure has a big impact on the extraction performance, which should be taken into account in actual application.
{"title":"Complex extraction of sulfonate dyes from wastewater and the effect of dye structure on extraction performance","authors":"Chengbing Yu, Zhenhua Zheng, Qingxuan Wang, Liyuan Zhang, Zhegnsheng Ma","doi":"10.1080/01496395.2023.2248368","DOIUrl":"https://doi.org/10.1080/01496395.2023.2248368","url":null,"abstract":"ABSTRACT In this study, the influences of sulfonate dye structure on the extraction rate, the reaction mechanism, and the complex ratio were studied. The parent structure and the number of sulfonic acid groups of sulfonate dyes have a great effect on extraction performance, whilst the molecular weight has a small effect on extraction performance. The results indicate that the extraction rate of azo dyes remains above 80% at the aqueous-organic phase ratio of 7:1, but the extraction rate of two anthraquinone dyes decreases to 54.9% and 34.9%, respectively; and the fewer the number of sulfonic acid groups of the dye, the better the extraction performance under the condition of insufficient extractant, the extraction rate of Direct Grey D and Acid Red M is over 82%. A complete set of methods for determining the ratio of the extractant and the dye was determined using the distribution coefficient method. The interaction between Telon Yellow 4 R and trioctylamine is ionic association and hydrogen bonding association, and the complex ratio between the dye and the extractant is about 2:1. In summary, dye structure has a big impact on the extraction performance, which should be taken into account in actual application.","PeriodicalId":21680,"journal":{"name":"Separation Science and Technology","volume":"21 1","pages":"2344 - 2356"},"PeriodicalIF":2.8,"publicationDate":"2023-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80660988","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 : 2023-08-13DOI: 10.1080/01496395.2023.2232096
Guangqun Tan, Yong Liu, Dan Xiao
ABSTRACT Alternanthera philoxeroides (AP) is a typical invasive plant. The quick spread of AP biomass may cause serious threat to ecological balance and biodiversity of the local area. However, AP has a high content of potassium, making it possible for preparing biochar through a self-activation process. In this study, AP biomass was employed to prepare porous carbon through a simple one-step pyrolysis. The effect of pyrolysis temperature (T) and carrier gas flow rate (v) onto the target carbon was intensively discussed. The obtained carbon were employed as adsorbents for methylene blue (MB) adsorption. Results showed that both of the T and v played great influence on the porous structure of the obtained biochar. Higher pyrolysis temperature and lower carrier gas flow rate were in favor of the formation of micropore and mesopore. The biochar obtained from 900°C pyrolysis temperature and 20 cm3 min−1 carrier gas flow rate (BC/900–20) possessed a satisfying specific surface area (825.6 m2 g−1) through the direct one-step pyrolysis, verifying the existence of pyrolysis gas self-activation and inorganic salt template self-activation effect. The maximum adsorption capacities calculated from Langmuir model were 424.9 mg g−1 for BC/900–20, which was comparable to that of the adsorbents reported recently.
摘要/ abstract摘要:黄菖蒲(ternanthera philoxeroides)是典型的入侵植物。AP生物量的迅速扩散可能对当地生态平衡和生物多样性造成严重威胁。然而，AP具有高钾含量，使其通过自激活过程制备生物炭成为可能。本研究以AP生物质为原料，通过简单的一步热解法制备多孔碳。重点讨论了热解温度(T)和载气流量(v)对目标碳的影响。所得碳作为吸附剂用于亚甲基蓝的吸附。结果表明，T和v对所得生物炭的多孔结构都有很大的影响。较高的热解温度和较低的载气流速有利于微孔和中孔的形成。在900℃热解温度和20 cm3 min - 1载气流速(BC/900 - 20)下，通过直接一步热解得到的生物炭具有令人满意的比表面积(825.6 m2 g - 1)，验证了热解气体自活化和无机盐模板自活化效应的存在。Langmuir模型计算的BC/ 900-20的最大吸附量为424.9 mg g−1，与最近报道的吸附剂相当。关键词:莲子草热解自活化吸附亚甲基蓝新颖以富钾生物质莲子草为前驱体，采用简单的一步自活化热解法制备多孔炭材料。重点讨论了热解温度和热解过程中载气流速对所得碳材料性能的影响。在900℃热解温度和20 cm3 min-1载气流速条件下制备的生物炭对亚甲基蓝具有满意的比表面积和吸附能力。作者感谢四川大学分析测试中心在FTIR, XRD和SEM分析方面的帮助。披露声明作者未报告潜在的利益冲突。本研究得到国家自然科学基金资助[81927809]
{"title":"Adsorption of methylene blue from aqueous solution on biochar prepared from a K-rich biomass <i>Alternanthera philoxeroides</i>","authors":"Guangqun Tan, Yong Liu, Dan Xiao","doi":"10.1080/01496395.2023.2232096","DOIUrl":"https://doi.org/10.1080/01496395.2023.2232096","url":null,"abstract":"ABSTRACT Alternanthera philoxeroides (AP) is a typical invasive plant. The quick spread of AP biomass may cause serious threat to ecological balance and biodiversity of the local area. However, AP has a high content of potassium, making it possible for preparing biochar through a self-activation process. In this study, AP biomass was employed to prepare porous carbon through a simple one-step pyrolysis. The effect of pyrolysis temperature (T) and carrier gas flow rate (v) onto the target carbon was intensively discussed. The obtained carbon were employed as adsorbents for methylene blue (MB) adsorption. Results showed that both of the T and v played great influence on the porous structure of the obtained biochar. Higher pyrolysis temperature and lower carrier gas flow rate were in favor of the formation of micropore and mesopore. The biochar obtained from 900°C pyrolysis temperature and 20 cm3 min−1 carrier gas flow rate (BC/900–20) possessed a satisfying specific surface area (825.6 m2 g−1) through the direct one-step pyrolysis, verifying the existence of pyrolysis gas self-activation and inorganic salt template self-activation effect. The maximum adsorption capacities calculated from Langmuir model were 424.9 mg g−1 for BC/900–20, which was comparable to that of the adsorbents reported recently.","PeriodicalId":21680,"journal":{"name":"Separation Science and Technology","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135309286","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 : 2023-08-13DOI: 10.1080/01496395.2023.2240492
Derya Yıldız, Izge Demir, H. Demiral
ABSTRACT Dye pollution is a very important problem that needs to be prevented due to its effects on ecosystem, human and animal health. Adsorption is an economical and easy treatment method used to remove these pollutants. Today, activated carbons, which are tried to be produced from renewable resources, are widely used adsorbents thanks to its low cost and advanced surface properties. The activated carbon (AC) in this study was produced from poplar sawdust by H3PO4 activation at an acid:sawdust ratio of 4:1 and a carbonization temperature of 400°C. This AC was used to adsorption of Malachite Green (MG) from aqueous solutions. According to the experimental results, the optimum adsorption conditions were determined as 6 h at pH 5 and 25°C with 0.1 g adsorbent at 300 mg/L initial concentration and 150 mg/g adsorption capacity was achieved these conditions. Adsorption kinetics, isotherms and thermodynamics were also investigated and the results were evaluated. Surface adsorption and intraparticle diffusion are effective in the adsorption mechanism of MG on poplar sawdust AC. Since the kinetic data fit the pseudo-second-order model, it can be said that the adsorption is chemisorption. Moreover, MG adsorption was spontaneous and endothermic on a monolayer homogeneous surface.
{"title":"Adsorption of malachite green on to poplar sawdust activated carbon","authors":"Derya Yıldız, Izge Demir, H. Demiral","doi":"10.1080/01496395.2023.2240492","DOIUrl":"https://doi.org/10.1080/01496395.2023.2240492","url":null,"abstract":"ABSTRACT Dye pollution is a very important problem that needs to be prevented due to its effects on ecosystem, human and animal health. Adsorption is an economical and easy treatment method used to remove these pollutants. Today, activated carbons, which are tried to be produced from renewable resources, are widely used adsorbents thanks to its low cost and advanced surface properties. The activated carbon (AC) in this study was produced from poplar sawdust by H3PO4 activation at an acid:sawdust ratio of 4:1 and a carbonization temperature of 400°C. This AC was used to adsorption of Malachite Green (MG) from aqueous solutions. According to the experimental results, the optimum adsorption conditions were determined as 6 h at pH 5 and 25°C with 0.1 g adsorbent at 300 mg/L initial concentration and 150 mg/g adsorption capacity was achieved these conditions. Adsorption kinetics, isotherms and thermodynamics were also investigated and the results were evaluated. Surface adsorption and intraparticle diffusion are effective in the adsorption mechanism of MG on poplar sawdust AC. Since the kinetic data fit the pseudo-second-order model, it can be said that the adsorption is chemisorption. Moreover, MG adsorption was spontaneous and endothermic on a monolayer homogeneous surface.","PeriodicalId":21680,"journal":{"name":"Separation Science and Technology","volume":"74 1","pages":"2099 - 2114"},"PeriodicalIF":2.8,"publicationDate":"2023-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88782689","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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