Pub Date : 2025-03-18DOI: 10.1016/j.seppur.2025.132595
Alvaro Represa, Marwan Laqdiem, Julio Garcia-Fayos, Laura Almar, Jose M. Serra
A key strategy for reducing greenhouse gas emissions is advancing carbon capture and storage (CCS) technologies, with oxycombustion playing a vital role in industrial decarbonization. Oxygen transport membranes (OTMs) enable flexible oxygen production and integration with catalytic membrane reactors (CMRs) to enhance process efficiency. However, OTMs with high permeation are unstable in CO2 and CH4 environments. This study investigates methane oxidation over Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) capillary membranes with the effect of protective catalytic layers of BSCF, Ce0.8Tb0.2O2-δ and Co2MnO4 / Ce0.8Tb0.2O2-δ. The developed catalytic membrane reactors, formed by BSCF membranes with these catalytic protective layers, achieved complete CH4 conversion and total selectivity for oxycombustion under the selected conditions while maintaining their performance and structural stability under CH4 and CO2 exposure.
{"title":"Optimization of oxycombustion capillary membrane reactors with protective and catalytic layers","authors":"Alvaro Represa, Marwan Laqdiem, Julio Garcia-Fayos, Laura Almar, Jose M. Serra","doi":"10.1016/j.seppur.2025.132595","DOIUrl":"https://doi.org/10.1016/j.seppur.2025.132595","url":null,"abstract":"A key strategy for reducing greenhouse gas emissions is advancing carbon capture and storage (CCS) technologies, with oxycombustion playing a vital role in industrial decarbonization. Oxygen transport membranes (OTMs) enable flexible oxygen production and integration with catalytic membrane reactors (CMRs) to enhance process efficiency. However, OTMs with high permeation are unstable in CO<sub>2</sub> and CH<sub>4</sub> environments. This study investigates methane oxidation over Ba<sub>0.5</sub>Sr<sub>0.5</sub>Co<sub>0.8</sub>Fe<sub>0.2</sub>O<sub>3-δ</sub> (BSCF) capillary membranes with the effect of protective catalytic layers of BSCF, Ce<sub>0.8</sub>Tb<sub>0.2</sub>O<sub>2-δ</sub> and Co<sub>2</sub>MnO<sub>4</sub> / Ce<sub>0.8</sub>Tb<sub>0.2</sub>O<sub>2-δ</sub>. The developed catalytic membrane reactors, formed by BSCF membranes with these catalytic protective layers, achieved complete CH<sub>4</sub> conversion and total selectivity for oxycombustion under the selected conditions while maintaining their performance and structural stability under CH<sub>4</sub> and CO<sub>2</sub> exposure.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"5 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Trace amount of Cr(VI) in water still threatens human health and ecology. Several reported amine-based adsorbents can remove trace Cr(VI) in acidic solutions of pH 2–5, but perform badly at neutral and alkaline conditions, which is insufficient for treating natural waters. Also, the chemical eluate leads to secondary pollution. Here, the amine-rich thermo-responsive poly(dimethylaminoethyl methacrylate) (pDMAEMA) was selected based on its high pKa value and introduced into MOFs to produce pDMAEMA-DUT-5 for effective removal of trace Cr(VI) from natural waters. The composite with a polymer loading of 23.4 wt% achieved the highest adsorption capacity of 182.2 mg g−1 under an optimized condition, that is, at pH 3 and 25 °C. Besides, this material effectively reduced trace Cr(VI) content in natural waters from 100 to 1 μg L−1 by one filtration in a column. Its high selectivity was verified and further confirmed by the strong adsorption energy of Cr(VI) and −N(CH3)2. Furthermore, the composite could be fully regenerated in 45 °C water within 10 min, concentrating Cr(VI) for 270 folds in one adsorption–desorption cycle and maintaining over 99 % performance after five cycles. It demonstrated excellent removal efficiency, high selectivity, and thermal regeneration stability. This work presents a simple strategy to design highly selective and sustainable ion adsorbents for effective removal of toxic ions or resource recovery, while its thermal regeneration function largely simplifies further treatments.
{"title":"Ultra–selective and sustainable extraction of trace Cr(VI) from real waters using a thermally regenerable MOF composite of pDMAEMA-DUT-5","authors":"Yilei Fang, Mengyu Tang, Xu Wu, Jiajie Zhang, Qian Guan, Yinzhou Luo, Xin Yu, Ranwen Ou","doi":"10.1016/j.seppur.2025.132601","DOIUrl":"https://doi.org/10.1016/j.seppur.2025.132601","url":null,"abstract":"Trace amount of Cr(VI) in water still threatens human health and ecology. Several reported amine-based adsorbents can remove trace Cr(VI) in acidic solutions of pH 2–5, but perform badly at neutral and alkaline conditions, which is insufficient for treating natural waters. Also, the chemical eluate leads to secondary pollution. Here, the amine-rich thermo-responsive poly(dimethylaminoethyl methacrylate) (pDMAEMA) was selected based on its high pK<sub>a</sub> value and introduced into MOFs to produce pDMAEMA-DUT-5 for effective removal of trace Cr(VI) from natural waters. The composite with a polymer loading of 23.4 wt% achieved the highest adsorption capacity of 182.2 mg g<sup>−1</sup> under an optimized condition, that is, at pH 3 and 25 °C. Besides, this material effectively reduced trace Cr(VI) content in natural waters from 100 to 1 μg L<sup>−1</sup> by one filtration in a column. Its high selectivity was verified and further confirmed by the strong adsorption energy of Cr(VI) and −N(CH<sub>3</sub>)<sub>2</sub>. Furthermore, the composite could be fully regenerated in 45 °C water within 10 min, concentrating Cr(VI) for 270 folds in one adsorption–desorption cycle and maintaining over 99 % performance after five cycles. It demonstrated excellent removal efficiency, high selectivity, and thermal regeneration stability. This work presents a simple strategy to design highly selective and sustainable ion adsorbents for effective removal of toxic ions or resource recovery, while its thermal regeneration function largely simplifies further treatments.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"19 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Loose nanofiltration (LNF) membranes based on interfacial polymerization (IP), such as polyester (PE) and polyamide (PA), are widely used in textile wastewater treatment. However, membrane fouling is unavoidable due to dye accumulation and salt scaling, resulting in a reduced membrane performance and reduced service life. Herein, we investigate the fouling behavior of two representative PE and PA LNF membranes, synthesized using quercetin and arginine as aqueous monomers via the IP technique, respectively. When the concentration factor (the ratio of the initial feed volume to the final concentrated volume) of the feed solution reaches 10 through the continuous process, comparing the fouling behavior of the PE and PA membrane, the water flux and Congo red/NaCl selectivity of the PE membrane decreased by 62.8 % and 26.9 % respectively, and that of the PA membrane decreased by 55.5 % and 13.9 %. The severe fouling of the PE membrane was mainly because of the large pore size and rough surface. Then, four cleaning agents were employed (NaOH, HCl, NaClO, and acetone solution) to clean the PE and PA membranes. A NaClO solution (300 ppm) was most effective for cleaning the PE membrane, while a pH 11 NaOH solution worked best for the PA membrane. Finally, cleaning strategies for the fouled PE and PA LNF membranes after textile wastewater treatment are proposed. Through the batch process involving both fouling and cleaning, when the concentration factor of the feed solution reaches 10, the cleaning efficiency of the PE membrane and the PA membrane are respectively 12.3 % and 5.9 % higher than that of the continuous process. This study highlights the importance of selecting appropriate cleaning agents and optimizing the cleaning strategy in maintaining the long-term stability and performance of LNF membranes, providing theoretical guidance for the cleaning of loose PE and PA membranes.
{"title":"Fouling behavior and cleaning strategies of polyester and polyamide loose nanofiltration membranes in textile wastewater treatment","authors":"Rui Zhao, Yafei Mao, Daliang Xu, Xinda You, Alexander Volodine, Qieyuan Gao, Junwei Li, Junfeng Zheng","doi":"10.1016/j.seppur.2025.132596","DOIUrl":"https://doi.org/10.1016/j.seppur.2025.132596","url":null,"abstract":"Loose nanofiltration (LNF) membranes based on interfacial polymerization (IP), such as polyester (PE) and polyamide (PA), are widely used in textile wastewater treatment. However, membrane fouling is unavoidable due to dye accumulation and salt scaling, resulting in a reduced membrane performance and reduced service life. Herein, we investigate the fouling behavior of two representative PE and PA LNF membranes, synthesized using quercetin and arginine as aqueous monomers via the IP technique, respectively. When the concentration factor (the ratio of the initial feed volume to the final concentrated volume) of the feed solution reaches 10 through the continuous process, comparing the fouling behavior of the PE and PA membrane, the water flux and Congo red/NaCl selectivity of the PE membrane decreased by 62.8 % and 26.9 % respectively, and that of the PA membrane decreased by 55.5 % and 13.9 %. The severe fouling of the PE membrane was mainly because of the large pore size and rough surface. Then, four cleaning agents were employed (NaOH, HCl, NaClO, and acetone solution) to clean the PE and PA membranes. A NaClO solution (300 ppm) was most effective for cleaning the PE membrane, while a pH 11 NaOH solution worked best for the PA membrane. Finally, cleaning strategies for the fouled PE and PA LNF membranes after textile wastewater treatment are proposed. Through the batch process involving both fouling and cleaning, when the concentration factor of the feed solution reaches 10, the cleaning efficiency of the PE membrane and the PA membrane are respectively 12.3 % and 5.9 % higher than that of the continuous process. This study highlights the importance of selecting appropriate cleaning agents and optimizing the cleaning strategy in maintaining the long-term stability and performance of LNF membranes, providing theoretical guidance for the cleaning of loose PE and PA membranes.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"40 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143640576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2025-03-18DOI: 10.1016/j.seppur.2025.132604
Houqi Zhou, Chi Fei, Ting Xu, Yilong Fan, Keying Tang, Chunyu Chen, Dianchun Ju, Han Ma, Zuoqiao Zhu, Rui Mao
Nowadays, membrane capacitive deionization technology, as an emerging method for seawater desalination, has attracted increasing attention and research efforts due to its ability to mitigate the co-ion effect and redox reactions associated with capacitive deionization, thereby significantly enhancing desalination adsorption capacity. In this study, N/P co-doped biomass carbon with a porous structure was synthesized using a one-step calcination method from sugarcane bagasse. The material exhibits excellent electrochemical and desalination performance, with a high specific surface area providing abundant active sites and enhancing ion transport efficiency. Appropriate N/P doping improved the electrochemical performance of the material, thereby enhancing the desalination performance in the MCDI process. The NP-ABS electrode demonstrated a high specific capacitance of 430.48F g-1 at a current density of 1 A g-1. In the MCDI experiment, a high adsorption capacity of 35.79 mg g-1 for Na+ was observed. During the adsorption of different ions, the adsorption capacity for Cr3+ reached as high as 46.61 mg g-1.After 50 adsorption–desorption cycles, the material retained 88.2 % of its initial capacity.DFT calculations revealed that NP doping significantly enhanced the adsorption performance of the material. Combined with the MCDI mechanism, the study highlighted the crucial role of hydration energy in MCDI. This material exhibits great potential for applications in seawater desalination.
{"title":"N/P co-doped modified porous carbon for high-efficiency membrane capacitance deionization in seawater desalination","authors":"Houqi Zhou, Chi Fei, Ting Xu, Yilong Fan, Keying Tang, Chunyu Chen, Dianchun Ju, Han Ma, Zuoqiao Zhu, Rui Mao","doi":"10.1016/j.seppur.2025.132604","DOIUrl":"https://doi.org/10.1016/j.seppur.2025.132604","url":null,"abstract":"Nowadays, membrane capacitive deionization technology, as an emerging method for seawater desalination, has attracted increasing attention and research efforts due to its ability to mitigate the co-ion effect and redox reactions associated with capacitive deionization, thereby significantly enhancing desalination adsorption capacity. In this study, N/P co-doped biomass carbon with a porous structure was synthesized using a one-step calcination method from sugarcane bagasse. The material exhibits excellent electrochemical and desalination performance, with a high specific surface area providing abundant active sites and enhancing ion transport efficiency. Appropriate N/P doping improved the electrochemical performance of the material, thereby enhancing the desalination performance in the MCDI process. The NP-ABS electrode demonstrated a high specific capacitance of 430.48F g<sup>-1</sup> at a current density of 1 A g<sup>-1</sup>. In the MCDI experiment, a high adsorption capacity of 35.79 mg g<sup>-1</sup> for Na<sup>+</sup> was observed. During the adsorption of different ions, the adsorption capacity for Cr<sup>3+</sup> reached as high as 46.61 mg g<sup>-</sup>1.After 50 adsorption–desorption cycles, the material retained 88.2 % of its initial capacity.DFT calculations revealed that NP doping significantly enhanced the adsorption performance of the material. Combined with the MCDI mechanism, the study highlighted the crucial role of hydration energy in MCDI. This material exhibits great potential for applications in seawater desalination.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"91 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143660531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2025-03-18DOI: 10.1016/j.seppur.2025.132593
Anjie Kang, Huanqi Chen, Qingge Feng, Xiang Sun, Zheng Liu
Sucralose (SUC) is a prevalent artificial sweetener with bio-accumulative effects, which is difficult to be removed by conventional wastewater treatment. A bimetallic carbon material of CoxTiy/C containing a high concentration of oxygen vacancies (OV) was successfully synthesized using one-pot solvothermal and carbon reduction methods. The characterization results showed that CoxTiy/C ensured well dispersion of bimetallic Co-Ti elements within the material. The Co1Ti2/C-PMS system presented excellent performance in the catalytic decomposition of SUC, and also achieved outstanding performance of anti-interference and cyclic stability. Due to the activity discrepancy of two metal for competing oxygen atoms, the high OV content of Co1Ti2/C was well presented, and triggered the SUC degradation pathway dominated by singlet oxygen (1O2) and complemented by hydroxyl radicals (•OH) and electron transfer. Based on the intermediates measured by LC-MS, the frontier molecular orbitals and Fukui functions of SUC were calculated using quantum chemistry to speculate the possible degradation pathways of SUC, and the eco-toxicity of its intermediates was also assessed, which showed that its intermediates were much lower than that of SUC. It was believed that Co1Ti2/C can serve a highly efficient and green catalyst for the degradation of organic pollutants. This study provides insights for the rational design and development of catalysts for artificial sweetener wastewater treatment.
{"title":"Defective carbon encapsulating bimetallic Co-Ti for the excellent degradation of sucralose: Regulating the generation and enhancement action of singlet oxygen","authors":"Anjie Kang, Huanqi Chen, Qingge Feng, Xiang Sun, Zheng Liu","doi":"10.1016/j.seppur.2025.132593","DOIUrl":"https://doi.org/10.1016/j.seppur.2025.132593","url":null,"abstract":"Sucralose (SUC) is a prevalent artificial sweetener with bio-accumulative effects, which is difficult to be removed by conventional wastewater treatment. A bimetallic carbon material of Co<sub>x</sub>Ti<sub>y</sub>/C containing a high concentration of oxygen vacancies (O<sub>V</sub>) was successfully synthesized using one-pot solvothermal and carbon reduction methods. The characterization results showed that Co<sub>x</sub>Ti<sub>y</sub>/C ensured well dispersion of bimetallic Co-Ti elements within the material. The Co<sub>1</sub>Ti<sub>2</sub>/C-PMS system presented excellent performance in the catalytic decomposition of SUC, and also achieved outstanding performance of anti-interference and cyclic stability. Due to the activity discrepancy of two metal for competing oxygen atoms, the high O<sub>V</sub> content of Co<sub>1</sub>Ti<sub>2</sub>/C was well presented, and triggered the SUC degradation pathway dominated by singlet oxygen (<sup>1</sup>O<sub>2</sub>) and complemented by hydroxyl radicals (•OH) and electron transfer. Based on the intermediates measured by LC-MS, the frontier molecular orbitals and Fukui functions of SUC were calculated using quantum chemistry to speculate the possible degradation pathways of SUC, and the eco-toxicity of its intermediates was also assessed, which showed that its intermediates were much lower than that of SUC. It was believed that Co<sub>1</sub>Ti<sub>2</sub>/C can serve a highly efficient and green catalyst for the degradation of organic pollutants. This study provides insights for the rational design and development of catalysts for artificial sweetener wastewater treatment.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"59 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143640586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2025-03-18DOI: 10.1016/j.seppur.2025.132436
Xia Hua, Yating Hu, Wei Hu, Yong Xu
Gluconobacter oxydans demonstrated a distinct selective divergence in biocatalysis of primary diols with varying carbon chain lengths for hydroxyl acids production. Therefore, molecular docking and molecular dynamics simulation were employed to investigate the binding mode between membrane-bound alchol dehydrogenase with primary diols and hydroxyl acids. The molecular docking results revealed that as carbon chain length of hydroxyl acids increased, the van der Waals interactions, which plays important binding role, significantly diminished from −8.31 to −25.75 kcal/mol, which suggesting that an increase in carbon chain length enhanced the binding affinity. The movement trajectory and dehydrogenase structural further confirmed that primary diols with C ≥ 5 could eventually convert to diacids, which elucidating the mechanism of region-selective biocatalysis. The simulation results of systems with varying protonation states constructed by constant pH method demonstrated that as pH increased to 6, the binding free energy of 5-hydroxyvaleric acid and dehydrogenase shifted from −18.48 to 10.84 kcal/mol, indicating a significant reduction in binding affinity. Moreover, by integrating multi-scale simulation indexes, it was determined that the critical pH regulatory points for the highly selective conversion of pentanol and hexanediol to hydroxyl acids, which were 5.5 and 7. The rational strategy of microsimulation guided macroscopic biocatalysis, which selectively converted 20 g/L pentadiol and hexanediol into 20.4 g/L and 19.2 g/L hydroxyl acids, thereby resulting in selective preparation of hydroxyl acids with C2-C6 by G. oxydans respectively. Importantly, the selective production technology effectively prevented the formation of diacid and enabled in situ separation and purification of hydroxyl acids from by-product.
{"title":"Regiodivergent catalytic mechanism of cellular membrane-bound dehydrogenase for the high selective bio-oxidation of primary diols","authors":"Xia Hua, Yating Hu, Wei Hu, Yong Xu","doi":"10.1016/j.seppur.2025.132436","DOIUrl":"https://doi.org/10.1016/j.seppur.2025.132436","url":null,"abstract":"<em>Gluconobacter oxydans</em> demonstrated a distinct selective divergence in biocatalysis of primary diols with varying carbon chain lengths for hydroxyl acids production. Therefore, molecular docking and molecular dynamics simulation were employed to investigate the binding mode between membrane-bound alchol dehydrogenase with primary diols and hydroxyl acids. The molecular docking results revealed that as carbon chain length of hydroxyl acids increased, the van der Waals interactions, which plays important binding role, significantly diminished from −8.31 to −25.75 kcal/mol, which suggesting that an increase in carbon chain length enhanced the binding affinity. The movement trajectory and dehydrogenase structural further confirmed that primary diols with C ≥ 5 could eventually convert to diacids, which elucidating the mechanism of region-selective biocatalysis. The simulation results of systems with varying protonation states constructed by constant pH method demonstrated that as pH increased to 6, the binding free energy of 5-hydroxyvaleric acid and dehydrogenase shifted from −18.48 to 10.84 kcal/mol, indicating a significant reduction in binding affinity. Moreover, by integrating multi-scale simulation indexes, it was determined that the critical pH regulatory points for the highly selective conversion of pentanol and hexanediol to hydroxyl acids, which were 5.5 and 7. The rational strategy of microsimulation guided macroscopic biocatalysis, which selectively converted 20 g/L pentadiol and hexanediol into 20.4 g/L and 19.2 g/L hydroxyl acids, thereby resulting in selective preparation of hydroxyl acids with C2-C6 by <em>G. oxydans</em> respectively. Importantly, the selective production technology effectively prevented the formation of diacid and enabled in situ separation and purification of hydroxyl acids from by-product.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"49 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The issue concerning selective activation within the in-situ formed peroxymonocarbonate (HCO4−)-based advanced oxidation process has been understudied. We selected oxygen vacancy-rich manganese dioxides (ε-MnO2-OV) and perfect crystalline ε-MnO2 as catalysts to initiate the activation of the coexisting oxidants (H2O2 and HCO4−) in an in-situ formed HCO4−-based system. Activation experiments, electron paramagnetic resonance (EPR) and correlation analysis between oxidant conversion and •OH production suggest that ε-MnO2-OV was inert for H2O2 decomposition, but active for HCO4− decomposition to produce reactive oxygen species, including •OH and CO3•−. Compared with ε-MnO2, approximately 4 times more •OH could be produced and many persistent organics could be removed more than 80 % in the ε-MnO2-OV-catalyzed HCO4−-based system. Moreover, a continuous-flow device was assembled and performed to remove tetracycline for 60 h with more than 80 % degradation efficiency. The catalyst characterization and density functional theory (DFT) calculations suggest that low-valent Mn species were the catalytic active sites and electron-deficient oxygen vacancy enhanced the adsorption of electron-rich HCO4−, accelerated electronic conduction and charge rearrangement between ε-MnO2-OV and HCO4−, thereby promoting the O-O bond cleavage of HCO4− for producing CO3•− and •OH. Free radical quenching experiments and catalytic mechanism indicated that CO3•− was responsible for the degradation and the produced •OH likely reduced the oxidized Mn species to finish the catalytic cycle. This work offers insights into the structure–activity relations of MnO2 catalysts in the selective activation of HCO4− for promoting •OH formation.
{"title":"Regulation of oxidant activation in a peroxymonocarbonate-based system by an oxygen vacancy-rich MnO2 catalyst","authors":"Yiqian Jiang, Zihan Shen, Zihan Yang, Peiqing Zhao, Xu Meng","doi":"10.1016/j.seppur.2025.132594","DOIUrl":"https://doi.org/10.1016/j.seppur.2025.132594","url":null,"abstract":"The issue concerning selective activation within the in-situ formed peroxymonocarbonate (HCO<sub>4</sub><sup>−</sup>)-based advanced oxidation process has been understudied. We selected oxygen vacancy-rich manganese dioxides (<em>ε</em>-MnO<sub>2</sub>-OV) and perfect crystalline <em>ε</em>-MnO<sub>2</sub> as catalysts to initiate the activation of the coexisting oxidants (H<sub>2</sub>O<sub>2</sub> and HCO<sub>4</sub><sup>−</sup>) in an in-situ formed HCO<sub>4</sub><sup>−</sup>-based system. Activation experiments, electron paramagnetic resonance (EPR) and correlation analysis between oxidant conversion and <sup>•</sup>OH production suggest that <em>ε</em>-MnO<sub>2</sub>-OV was inert for H<sub>2</sub>O<sub>2</sub> decomposition, but active for HCO<sub>4</sub><sup>−</sup> decomposition to produce reactive oxygen species, including <sup>•</sup>OH and CO<sub>3</sub><sup>•−</sup>. Compared with <em>ε</em>-MnO<sub>2</sub>, approximately 4 times more <sup>•</sup>OH could be produced and many persistent organics could be removed more than 80 % in the <em>ε</em>-MnO<sub>2</sub>-OV-catalyzed HCO<sub>4</sub><sup>−</sup>-based system. Moreover, a continuous-flow device was assembled and performed to remove tetracycline for 60 h with more than 80 % degradation efficiency. The catalyst characterization and density functional theory (DFT) calculations suggest that low-valent Mn species were the catalytic active sites and electron-deficient oxygen vacancy enhanced the adsorption of electron-rich HCO<sub>4</sub><sup>−</sup>, accelerated electronic conduction and charge rearrangement between <em>ε</em>-MnO<sub>2</sub>-OV and HCO<sub>4</sub><sup>−</sup>, thereby promoting the O-O bond cleavage of HCO<sub>4</sub><sup>−</sup> for producing CO<sub>3</sub><sup>•−</sup> and <sup>•</sup>OH. Free radical quenching experiments and catalytic mechanism indicated that CO<sub>3</sub><sup>•−</sup> was responsible for the degradation and the produced <sup>•</sup>OH likely reduced the oxidized Mn species to finish the catalytic cycle. This work offers insights into the structure–activity relations of MnO<sub>2</sub> catalysts in the selective activation of HCO<sub>4</sub><sup>−</sup> for promoting <sup>•</sup>OH formation.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"91 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2025-03-18DOI: 10.1016/j.seppur.2025.132602
Muhammad Umar, Mohammad Fikry, Natthaporn Phonsatta, Atikorn Panya, Nashi K. Alqahtani, Saeid Jafari, Kitipong Assatarakul
Hemp seed extract (HSE) was prepared using ultrasonic-assisted extraction (UAE) in an aqueous medium as a green solvent. The effect of ultrasonication factors including power, time, and temperature, was studied on the energy consumption (EC) of the ultrasonication, extraction yield (EY), antioxidant activity (DPPH free radical scavenging activity), total phenolic content (TPC), and total flavonoid content (TFC) of HSE. The ultrasonication factors showed a significant effect (p < 0.05) on the EC of ultrasonication, EY, TPC, TFC, and DPPH activity of HSE. The ultrasonication process was optimized at minimum EC and maximum TPC, EY, TFC, and DPPH activity of HSE and the ultrasonication power of 385 W for 30 min at 60 °C were obtained as optimum conditions. Moreover, a good association between predicted and experimental values was observed which validated the model. The response values at optimum conditions were 690.9 kj of EC, 13.2 % of EY, 85.4 mg GAE/mL of TPC, 106.1 mg QE/mL of TFC, and 79.4 % of DPPH activity. The thermodynamic analysis of the ultrasonication process revealed the endothermicity and spontaneity of the process. The ultrasonication process significantly improved the extraction of bioactive compounds from hemp seeds which can be beneficial for industrial applications.
{"title":"Ultrasonic-Assisted extraction of bioactive compounds from hemp seeds: Process optimization, energy efficiency, and antioxidant activity evaluation","authors":"Muhammad Umar, Mohammad Fikry, Natthaporn Phonsatta, Atikorn Panya, Nashi K. Alqahtani, Saeid Jafari, Kitipong Assatarakul","doi":"10.1016/j.seppur.2025.132602","DOIUrl":"https://doi.org/10.1016/j.seppur.2025.132602","url":null,"abstract":"Hemp seed extract (HSE) was prepared using ultrasonic-assisted extraction (UAE) in an aqueous medium as a green solvent. The effect of ultrasonication factors including power, time, and temperature, was studied on the energy consumption (EC) of the ultrasonication, extraction yield (EY), antioxidant activity (DPPH free radical scavenging activity), total phenolic content (TPC), and total flavonoid content (TFC) of HSE. The ultrasonication factors showed a significant effect (<em>p</em> < 0.05) on the EC of ultrasonication, EY, TPC, TFC, and DPPH activity of HSE. The ultrasonication process was optimized at minimum EC and maximum TPC, EY, TFC, and DPPH activity of HSE and the ultrasonication power of 385 W for 30 min at 60 °C were obtained as optimum conditions. Moreover, a good association between predicted and experimental values was observed which validated the model. The response values at optimum conditions were 690.9 kj of EC, 13.2 % of EY, 85.4 mg GAE/mL of TPC, 106.1 mg QE/mL of TFC, and 79.4 % of DPPH activity. The thermodynamic analysis of the ultrasonication process revealed the endothermicity and spontaneity of the process. The ultrasonication process significantly improved the extraction of bioactive compounds from hemp seeds which can be beneficial for industrial applications.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"20 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The development of S-scheme heterojunction photo-Fenton system with high catalytic activity is of great significance. Herein, FeS2/BaFe12O19 (SBFO) S-scheme heterojunction composites were prepared by in-situ sulfurization of BaFe12O19, which were subsequently employed in the photo-Fenton technique (500 µL H2O2) for the effective degradation of 100 mL of imidacloprid (10 ppm). Utilizing the internal electric field (IEF) established between the in-situ grown FeS2 and BaFe12O19, along with the synergistic effects arising from their suitable band structures, the optimized composite sample demonstrated a reaction rate of 0.1136 min−1 (Kinetic model: R2>0.98). In the presence of the internal electric field (IEF), electrons at the SBFO interface migrate from BaFe12O19 to FeS2, thus establishing an S-scheme heterojunction that facilitates the efficient separation of charge carriers and the rapid generation of free radicals. Moreover, the sulfurized SBFO not only preserved its outstanding magnetic separation capability (21 emu/g) but also maintained over 90 % removal efficiency of imidacloprid after 4 cycles. Additionally, its morphology and structure remained comparable to those observed prior to the reaction. Furthermore, mung bean cultivation experiments were carried out to assess the toxicity of the intermediates. The rhizomes of mung beans grown with detoxified culture medium can grow to approximately 15 cm in length, which exhibit a considerable increase in length compared to the undetoxified rhizomes. The toxicity of intermediate products was further analyzed in detail using toxicity assessment software tools such as T.E.S.T and ECOSAR. Low-power LED lamps (30 W) demonstrate a degradation rate comparable to that of Xe lamp light sources (250 W) (LED: 0.1136 min−1, Xe lamp: 0.0794 min−1). This work offers an efficient approach for the degradation of organic pollutants by using magnetic material-based composites in combination with advanced oxidation technology.
{"title":"S-scheme heterojunction FeS2/BaFe12O19 by in-situ sulfurization strategy for boosting photocatalytic degradation activity","authors":"Zeyang Sun, Puyang Zhou, Yan Wang, Yu Gan, Jia Yan, Tingting Zhang, Meng Xie, Jimin Xie, Suci Meng, Yuanguo Xu","doi":"10.1016/j.seppur.2025.132607","DOIUrl":"https://doi.org/10.1016/j.seppur.2025.132607","url":null,"abstract":"The development of S-scheme heterojunction photo-Fenton system with high catalytic activity is of great significance. Herein, FeS<sub>2</sub>/BaFe<sub>12</sub>O<sub>19</sub> (SBFO) S-scheme heterojunction composites were prepared by in-situ sulfurization of BaFe<sub>12</sub>O<sub>19</sub>, which were subsequently employed in the photo-Fenton technique (500 µL H<sub>2</sub>O<sub>2</sub>) for the effective degradation of 100 mL of imidacloprid (10 ppm). Utilizing the internal electric field (IEF) established between the in-situ grown FeS<sub>2</sub> and BaFe<sub>12</sub>O<sub>19</sub>, along with the synergistic effects arising from their suitable band structures, the optimized composite sample demonstrated a reaction rate of 0.1136 min<sup>−1</sup> (Kinetic model: R<sup>2</sup>>0.98). In the presence of the internal electric field (IEF), electrons at the SBFO interface migrate from BaFe<sub>12</sub>O<sub>19</sub> to FeS<sub>2</sub>, thus establishing an S-scheme heterojunction that facilitates the efficient separation of charge carriers and the rapid generation of free radicals. Moreover, the sulfurized SBFO not only preserved its outstanding magnetic separation capability (21 emu/g) but also maintained over 90 % removal efficiency of imidacloprid after 4 cycles. Additionally, its morphology and structure remained comparable to those observed prior to the reaction. Furthermore, mung bean cultivation experiments were carried out to assess the toxicity of the intermediates. The rhizomes of mung beans grown with detoxified culture medium can grow to approximately 15 cm in length, which exhibit a considerable increase in length compared to the undetoxified rhizomes. The toxicity of intermediate products was further analyzed in detail using toxicity assessment software tools such as T.E.S.T and ECOSAR. Low-power LED lamps (30 W) demonstrate a degradation rate comparable to that of Xe lamp light sources (250 W) (LED: 0.1136 min<sup>−1</sup>, Xe lamp: 0.0794 min<sup>−1</sup>). This work offers an efficient approach for the degradation of organic pollutants by using magnetic material-based composites in combination with advanced oxidation technology.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"1 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2025-03-18DOI: 10.1016/j.seppur.2025.132590
Haoqiu Chen, Kaifeng Du
A weakness in compressive strength of cellulose microspheres has greatly restricted its application, especially in separation and purification. Herein, a novel strategy called mild solution exchange (MSE) is proposed to construct cellulose microspheres of high strength and permeability (MCM). MSE strategy provides cellulose chains with more sufficient assembling and stacking in antiparallel orientation, achieving homogeneous regeneration of cellulose framework, eventually results in higher crystallinity of cellulose microspheres. In particular, MCMs exhibit lower back pressure, higher permeability than cellulose microspheres fabricated via normal solution exchange strategy (NCM). Meanwhile, reserving hierarchical macro-meso-micropore renders MCM of outstanding mass transfer rates and abundant adsorption sites. Besides, the proposed microspheres are modified with 4-Formylphenylboronic acid (BA-MCMs) and then applied to adsorption evaluation. Excellent structural features and specific functional groups provide adsorbents with outstanding adsorption capabilities toward cis-diol-containing molecule. BA-MCMs show a high adsorption capacity, fast separation and excellent breakthrough characteristic
{"title":"High mechanical strength cellulose microspheres with homogeneous regeneration framework achieved by mild solvent exchange strategy for adsorption of flavonoids","authors":"Haoqiu Chen, Kaifeng Du","doi":"10.1016/j.seppur.2025.132590","DOIUrl":"https://doi.org/10.1016/j.seppur.2025.132590","url":null,"abstract":"A weakness in compressive strength of cellulose microspheres has greatly restricted its application, especially in separation and purification. Herein, a novel strategy called mild solution exchange (MSE) is proposed to construct cellulose microspheres of high strength and permeability (MCM). MSE strategy provides cellulose chains with more sufficient assembling and stacking in antiparallel orientation, achieving homogeneous regeneration of cellulose framework, eventually results in higher crystallinity of cellulose microspheres. In particular, MCMs exhibit lower back pressure, higher permeability than cellulose microspheres fabricated via normal solution exchange strategy (NCM). Meanwhile, reserving hierarchical macro-<em>meso</em>-micropore renders MCM of outstanding mass transfer rates and abundant adsorption sites. Besides, the proposed microspheres are modified with 4-Formylphenylboronic acid (BA-MCMs) and then applied to adsorption evaluation. Excellent structural features and specific functional groups provide adsorbents with outstanding adsorption capabilities toward <em>cis</em>-diol-containing molecule. BA-MCMs show a high adsorption capacity, fast separation and excellent breakthrough characteristic","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"90 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}