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}
Pub Date : 2023-08-10DOI: 10.1080/01496395.2023.2245134
Tooba Saeed, Abdul Naeem, Bashir Ahmad, Shaista Afridi, Ihtisham Wali Khan, Fouzia Perveen, Israf Ud Din, Nazish Huma Khan
ABSTRACTThe efficiency of the metal-organic framework of zinc (MOF-74) and its chitosan composite (CS/MOF-74) as a potential sorbent for the elimination of azo in addition to thiazine-type dyes from water by subsequent adsorption was studied. The synthesized adsorbents were characterized by various characterization techniques. The chitosan composite exhibited tremendous adsorption properties toward methyl orange (MO) and methylene blue (MB) at pH < 5.5 and pH > 5.5, respectively. The equilibrium data were evaluated by Dubinin-Radushkevich, Langmuir, Freundlich, and Tempkin isotherm models where the Langmuir model was best fitted to the adsorption data. The mono-layer sorption capacity values were found to be in the order 2047 mg/g and 1363 mg/g for MO and MB respectively onto CS/MOF-74 which are almost 6–8 epochs superior to MOF-74 and CS. In addition, pseudo-first, pseudo-second, intraparticle diffusion and Richenberg kinetic models were assessed to the kinetic data where the pseudo-second-order fitted very well to the adsorption data. The higher values of diffusion coefficient confirmed the greater involvement of the film diffusion than the pore and surface diffusion for the elimination of basic as well as acidic dyes onto CS/mOF-74. Thermodynamically, the negative value of isosteric heat of adsorption (ΔHˉ) concluded that the current study was found exothermic in nature. Moreover, electrostatic interactions, hydrogen bonding, and electron donor–acceptor interactions were suggested as probable mechanisms in the current adsorption process. The current study estimates the industrial importance of a chitosan composite of MOF-74 as it requires a short adsorption equilibrium time for the removal of the dyes and is satisfactorily reusable.KEYWORDS: Chitosankineticsmofsmethyl orangepolymerthermodynamics Highlights The adsorption capacity of CS/MOF-74 6–8 times greater than its counterparts.The dominant interactions for dyes removal were electrostatic and hydrogen bonding.After five cycles of regeneration, the adsorption capacity was found to be 70%.AcknowledgmentsThe authors would like to convey their gratitude to the Prince Sattam Bin Abdulaziz University (project number PSAU/2023/R/1444), Al-Kharj 16278, Saudi Arabia, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar Pakistan, and Bacha Khan University, Charsadda, Pakistan for providing us with the necessary support and facilities to carry out this study.Disclosure statementNo potential conflict of interest was reported by the authors.Novelty statementThe literature revealed that the porous structure and ultra-high surface area make Zinc MOF (MOF-74) an excellent adsorbent for the removal of dyes from aqueous media. However, to date, less consideration has been paid to the chitosan composite of MOF-74 for the efficient removal of dyes. The current study focuses on the novel adsorbent, i.e. chitosan (CS) composite of MOF-74 for the removal of MB and MO for the firs
{"title":"Synthesis and spectroscopic characteristics of chitosan composite of zinc-based metal-organic framework for rapid adsorption of organic pollutants from aqueous media","authors":"Tooba Saeed, Abdul Naeem, Bashir Ahmad, Shaista Afridi, Ihtisham Wali Khan, Fouzia Perveen, Israf Ud Din, Nazish Huma Khan","doi":"10.1080/01496395.2023.2245134","DOIUrl":"https://doi.org/10.1080/01496395.2023.2245134","url":null,"abstract":"ABSTRACTThe efficiency of the metal-organic framework of zinc (MOF-74) and its chitosan composite (CS/MOF-74) as a potential sorbent for the elimination of azo in addition to thiazine-type dyes from water by subsequent adsorption was studied. The synthesized adsorbents were characterized by various characterization techniques. The chitosan composite exhibited tremendous adsorption properties toward methyl orange (MO) and methylene blue (MB) at pH < 5.5 and pH > 5.5, respectively. The equilibrium data were evaluated by Dubinin-Radushkevich, Langmuir, Freundlich, and Tempkin isotherm models where the Langmuir model was best fitted to the adsorption data. The mono-layer sorption capacity values were found to be in the order 2047 mg/g and 1363 mg/g for MO and MB respectively onto CS/MOF-74 which are almost 6–8 epochs superior to MOF-74 and CS. In addition, pseudo-first, pseudo-second, intraparticle diffusion and Richenberg kinetic models were assessed to the kinetic data where the pseudo-second-order fitted very well to the adsorption data. The higher values of diffusion coefficient confirmed the greater involvement of the film diffusion than the pore and surface diffusion for the elimination of basic as well as acidic dyes onto CS/mOF-74. Thermodynamically, the negative value of isosteric heat of adsorption (ΔHˉ) concluded that the current study was found exothermic in nature. Moreover, electrostatic interactions, hydrogen bonding, and electron donor–acceptor interactions were suggested as probable mechanisms in the current adsorption process. The current study estimates the industrial importance of a chitosan composite of MOF-74 as it requires a short adsorption equilibrium time for the removal of the dyes and is satisfactorily reusable.KEYWORDS: Chitosankineticsmofsmethyl orangepolymerthermodynamics Highlights The adsorption capacity of CS/MOF-74 6–8 times greater than its counterparts.The dominant interactions for dyes removal were electrostatic and hydrogen bonding.After five cycles of regeneration, the adsorption capacity was found to be 70%.AcknowledgmentsThe authors would like to convey their gratitude to the Prince Sattam Bin Abdulaziz University (project number PSAU/2023/R/1444), Al-Kharj 16278, Saudi Arabia, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar Pakistan, and Bacha Khan University, Charsadda, Pakistan for providing us with the necessary support and facilities to carry out this study.Disclosure statementNo potential conflict of interest was reported by the authors.Novelty statementThe literature revealed that the porous structure and ultra-high surface area make Zinc MOF (MOF-74) an excellent adsorbent for the removal of dyes from aqueous media. However, to date, less consideration has been paid to the chitosan composite of MOF-74 for the efficient removal of dyes. The current study focuses on the novel adsorbent, i.e. chitosan (CS) composite of MOF-74 for the removal of MB and MO for the firs","PeriodicalId":21680,"journal":{"name":"Separation Science and Technology","volume":"206 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135553096","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 : 2023-08-08DOI: 10.1080/01496395.2023.2245135
Regilene de Sousa Silva, Heloísa Duarte Rengel, Francis Dalponte Voigt, R. Machado, Regina de Fátima Peralta Muniz Moreira, C. Marangoni
ABSTRACT This study investigated the water recovery of real textile wastewater by Coagulation/Flocculation (CF) integrated with Direct Contact Membrane Distillation (DCMD). The proof-of-concept tests were studied with synthetic solutions of reactive and disperse black dyes at different concentrations, and real textile wastewater from the discharge machine and the equalization tank. Results showed that CF-DCMD exhibited higher permeate fluxes (up to 40%) than single DCMD and maximum color rejection rates (100%). Moreover, CF-DCMD enabled water reclamation from cotton and polyester dyeing wastewater which was not possible by MD (Membrane Distillation). The integrated system showed excellent chemical oxygen demand removal capacity, total suspended solids, turbidity, conductivity reduction, and removed any signs of toxicity from the tested wastewater. The coagulation/flocculation process prior to the MD reduced the fouling factor for all wastewater, highlighting the equalization tank where a reduction of around 72% was observed, achieving the goal of reducing fouling and increasing the efficiency of the MD. Membrane characterization indicated that CF-DCMD confirmed less fouling of membranes than single DCMD. Thus, this study allows to understand the potential and robustness of the CF-DCMD process in the treatment of textile wastewater and that it is possible to develop alternative technologies to treat complex wastewater effectively. GRAPHICAL ABSTRACT
{"title":"Treatment of real textile wastewater by coagulation/flocculation integrated with direct contact membrane distillation","authors":"Regilene de Sousa Silva, Heloísa Duarte Rengel, Francis Dalponte Voigt, R. Machado, Regina de Fátima Peralta Muniz Moreira, C. Marangoni","doi":"10.1080/01496395.2023.2245135","DOIUrl":"https://doi.org/10.1080/01496395.2023.2245135","url":null,"abstract":"ABSTRACT This study investigated the water recovery of real textile wastewater by Coagulation/Flocculation (CF) integrated with Direct Contact Membrane Distillation (DCMD). The proof-of-concept tests were studied with synthetic solutions of reactive and disperse black dyes at different concentrations, and real textile wastewater from the discharge machine and the equalization tank. Results showed that CF-DCMD exhibited higher permeate fluxes (up to 40%) than single DCMD and maximum color rejection rates (100%). Moreover, CF-DCMD enabled water reclamation from cotton and polyester dyeing wastewater which was not possible by MD (Membrane Distillation). The integrated system showed excellent chemical oxygen demand removal capacity, total suspended solids, turbidity, conductivity reduction, and removed any signs of toxicity from the tested wastewater. The coagulation/flocculation process prior to the MD reduced the fouling factor for all wastewater, highlighting the equalization tank where a reduction of around 72% was observed, achieving the goal of reducing fouling and increasing the efficiency of the MD. Membrane characterization indicated that CF-DCMD confirmed less fouling of membranes than single DCMD. Thus, this study allows to understand the potential and robustness of the CF-DCMD process in the treatment of textile wastewater and that it is possible to develop alternative technologies to treat complex wastewater effectively. GRAPHICAL ABSTRACT","PeriodicalId":21680,"journal":{"name":"Separation Science and Technology","volume":"98 1","pages":"2394 - 2410"},"PeriodicalIF":2.8,"publicationDate":"2023-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74865879","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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