The abundant triazine rings with the good affinity for CO2 molecules in covalent triazine frameworks (CTFs) can capture and activate CO2 molecules, making CTFs a potential candidate for CO2 cycloaddition reaction. However, due to the single active site, the realization of high catalytic performance commonly requires the assistance of cocatalysts or harsh reaction conditions. In this study, several novel ionic covalent triazine frameworks (MCTFs, BCTFs and YCTFs) multifunctional heterogeneous catalysts were synthesized for CO2 cycloaddition reactions. The prepared CTFs catalysts have outstanding pore structure and uniformly distributed active sites (N Lewis basic sites in triazine ring and Cl– nucleophilic sites). The optimal catalyst MCTF-10 has good CO2 enrichment capacity and high adsorption selectivity. In addition, the catalyst shows an outstanding catalytic performance for the coupling reaction of CO2 and propylene oxide, with 96 % of yield and 99 % of selectivity for the product under metal-, solvent- and cocatalyst-free parameters (110 °C, initial CO2 pressure 1 MPa, 4 h). Even under diluted CO2 concentration (15 % CO2, 85 % N2) and mild conditions (80 °C, 0.1 MPa, 24 h), the synthetized CTFs exhibits an outstanding catalytic activity. The excellent catalytic performance, along with the good cycling stability and broad applicability of epoxides, make it a competitive catalyst for catalyzing the CO2 cycloaddition reaction.
共价三嗪框架（CTFs）中丰富的三嗪环对二氧化碳分子具有良好的亲和性，可以捕获和活化二氧化碳分子，使其成为二氧化碳环加成反应的潜在候选物质。然而，由于活性位点单一，要实现高催化性能通常需要助催化剂的辅助或苛刻的反应条件。本研究合成了几种新型离子共价三嗪框架（MCTFs、BCTFs 和 YCTFs）多功能异相催化剂，用于 CO2 环加成反应。所制备的 CTFs 催化剂具有优异的孔隙结构和均匀分布的活性位点（三嗪环中的 N Lewis 碱性位点和 Cl- 亲核位点）。最佳催化剂 MCTF-10 具有良好的二氧化碳富集能力和较高的吸附选择性。此外，该催化剂在二氧化碳与环氧丙烷的偶联反应中表现出卓越的催化性能，在不含金属、溶剂和助催化剂的参数条件下（110 °C，初始二氧化碳压力 1 兆帕，4 小时），产率达 96%，产物选择性达 99%。即使在稀释的二氧化碳浓度（15 % CO2、85 % N2）和温和条件（80 °C、0.1 兆帕、24 小时）下，合成的 CTFs 也表现出卓越的催化活性。优异的催化性能、良好的循环稳定性和对环氧化物的广泛适用性，使其成为催化 CO2 环加成反应的一种极具竞争力的催化剂。
{"title":"Multifunctional ionic covalent triazine framework as heterogeneous catalysts for efficient CO2 cycloaddition","authors":"Yingxuan Wen, Fangfang Zhang, Jingru Dou, Shougui Wang, Fei Gao, Falong Shan, Jipeng Dong, Guanghui Chen","doi":"10.1016/j.seppur.2024.130579","DOIUrl":"https://doi.org/10.1016/j.seppur.2024.130579","url":null,"abstract":"The abundant triazine rings with the good affinity for CO<sub>2</sub> molecules in covalent triazine frameworks (CTFs) can capture and activate CO<sub>2</sub> molecules, making CTFs a potential candidate for CO<sub>2</sub> cycloaddition reaction. However, due to the single active site, the realization of high catalytic performance commonly requires the assistance of cocatalysts or harsh reaction conditions. In this study, several novel ionic covalent triazine frameworks (MCTFs, BCTFs and YCTFs) multifunctional heterogeneous catalysts were synthesized for CO<sub>2</sub> cycloaddition reactions. The prepared CTFs catalysts have outstanding pore structure and uniformly distributed active sites (N Lewis basic sites in triazine ring and Cl<sup>–</sup> nucleophilic sites). The optimal catalyst MCTF-10 has good CO<sub>2</sub> enrichment capacity and high adsorption selectivity. In addition, the catalyst shows an outstanding catalytic performance for the coupling reaction of CO<sub>2</sub> and propylene oxide, with 96 % of yield and 99 % of selectivity for the product under metal-, solvent- and cocatalyst-free parameters (110 °C, initial CO<sub>2</sub> pressure 1 MPa, 4 h). Even under diluted CO<sub>2</sub> concentration (15 % CO<sub>2</sub>, 85 % N<sub>2</sub>) and mild conditions (80 °C, 0.1 MPa, 24 h), the synthetized CTFs exhibits an outstanding catalytic activity. The excellent catalytic performance, along with the good cycling stability and broad applicability of epoxides, make it a competitive catalyst for catalyzing the CO<sub>2</sub> cycloaddition reaction.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"76 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142665295","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}
Finding clean dual functional materials which can simultaneously alleviate energy and environmental issues is currently a research hotspot. In our work, TiO2/CQDs/NH2-MIL-125 photoanode system was constructed to explore the application of metal–organic frameworks (MOFs) materials in water splitting and biomedical wastewater treatment. The photocurrent density of the optimal TiO2/CQDs/NH2-MIL-125 photoanode reaches 1.7 mA/cm2 at 1.23 V vs. RHE, which is about 1.8 times that of pristine TiO2. More importantly, optimized photoanode displays an excellent remove ratio toward tetracycline hydrochloride of 74 % within 60 min. Through mechanism exploration, the excellent performance is attributed to the narrow band gap of NH2-MIL-125 widens the light absorption range to the visible region. Additionally, the specific electron conduction behavior of CQDs and the type Ⅱ heterojunction between TiO2/NH2-MIL-125 inhibited the photogenerated electron-hole recombination. This work explores the application of photoelectrochemical (PEC) materials in environmental catalytic clean production.
{"title":"Ultrathin metal–organic framework synergizes with carbon quantum dots improving photoelectrochemical water oxidation and tetracycline hydrochloride degradation performance","authors":"Ruyi Wang, Xingzhi Li, Yuxin Kan, Wenjun Fang, Caiyun Chen, Yongyan Chen, Lingling Wang, Yong Jia","doi":"10.1016/j.seppur.2024.130589","DOIUrl":"https://doi.org/10.1016/j.seppur.2024.130589","url":null,"abstract":"Finding clean dual functional materials which can simultaneously alleviate energy and environmental issues is currently a research hotspot. In our work, TiO<sub>2</sub>/CQDs/NH<sub>2</sub>-MIL-125 photoanode system was constructed to explore the application of metal–organic frameworks (MOFs) materials in water splitting and biomedical wastewater treatment. The photocurrent density of the optimal TiO<sub>2</sub>/CQDs/NH<sub>2</sub>-MIL-125 photoanode reaches 1.7 mA/cm<sup>2</sup> at 1.23 V vs. RHE, which is about 1.8 times that of pristine TiO<sub>2</sub>. More importantly, optimized photoanode displays an excellent remove ratio toward tetracycline hydrochloride of 74 % within 60 min. Through mechanism exploration, the excellent performance is attributed to the narrow band gap of NH<sub>2</sub>-MIL-125 widens the light absorption range to the visible region. Additionally, the specific electron conduction behavior of CQDs and the type Ⅱ heterojunction between TiO<sub>2</sub>/NH<sub>2</sub>-MIL-125 inhibited the photogenerated electron-hole recombination. This work explores the application of photoelectrochemical (PEC) materials in environmental catalytic clean production.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"50 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142665291","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 activity and selectivity of the carbon dioxide reduction reaction (CO2RR) can be significantly enhanced by altering the electronic structure of central transition-metal atoms in single-atom catalysts (SACs). However, the role of mass transport in catalyst design, though critical, is frequently overlooked. Herein, a single-atom Ni-N-C(P)-8 catalyst featuring hierarchical micropores and mesopores is synthesized to investigate the role of the mass transport process in CO2RR. Remarkably, the mesopores-rich catalyst can efficiently decrease the mass transport barrier, achieving a high CO Faradaic efficiency (FE) of 99 % at −0.7 V vs. reversible hydrogen electrode (RHE) and turnover frequencies (TOFs) for CO production of 31644 h−1 at −0.9 V vs. RHE. The detailed experiments and classical molecular dynamics simulations reveal that the abundance of mesoporous pores on the catalyst surface significantly enhances the mass transport process to the active Ni sites during the reaction, and thereby enhancing the CO production rate.
{"title":"Enhanced mass transport on single-atom Ni-N-C catalysts with hierarchical pore structures for efficient CO2 electroreduction","authors":"Xiaojiao Shao, Zongkun Bian, Bingqiang Li, Faqi Zhan, Xiang Cheng, Yongqian Shen, Zhixia Li, Qi Zhou, Rongsheng Cai, Chenchen Feng","doi":"10.1016/j.seppur.2024.130576","DOIUrl":"https://doi.org/10.1016/j.seppur.2024.130576","url":null,"abstract":"The activity and selectivity of the carbon dioxide reduction reaction (CO<sub>2</sub>RR) can be significantly enhanced by altering the electronic structure of central transition-metal atoms in single-atom catalysts (SACs). However, the role of mass transport in catalyst design, though critical, is frequently overlooked. Herein, a single-atom Ni-N-C(P)-8 catalyst featuring hierarchical micropores and mesopores is synthesized to investigate the role of the mass transport process in CO<sub>2</sub>RR. Remarkably, the mesopores-rich catalyst can efficiently decrease the mass transport barrier, achieving a high CO Faradaic efficiency (FE) of 99 % at −0.7 V vs. reversible hydrogen electrode (RHE) and turnover frequencies (TOFs) for CO production of 31644 h<sup>−1</sup> at −0.9 V vs. RHE. The detailed experiments and classical molecular dynamics simulations reveal that the abundance of mesoporous pores on the catalyst surface significantly enhances the mass transport process to the active Ni sites during the reaction, and thereby enhancing the CO production rate.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"8 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642715","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}
Metal-based catalyst could be used for efficient peroxymonosulfate (PMS) activation, but inevitably suffered from metal ion leaching. Metal-free graphitic carbon nitride (g-C3N4) materials that can activate PMS are more conducive for practical water treatment. In this study, g-C3N4 with both N-defects and P-doping (CN-NP) was synthesized, which mainly produce singlet oxygen (1O2), and 97 % of 4-CP (4-Chlorophenol) was removed by CN-NP/PMS/Vis reaction system within 60 min. The active species was identified by quenching experiments and electron spin resonance (ESR) tests, and the origin of mainly active species was further verified by the concentration change of PMS during the reaction. It was verified by experiments and theoretical calculations that the introduction of N-defects led to the separation of photoinduced electron-hole pairs and improved photocatalytic activity. Notably, density functional theory (DFT) revealed that both N-defects and P-doping are electron-deficient sites, and P-doping acts as the main PMS adsorption site to promote the loss of electrons from PMS to generate 1O2. In addition, the catalysts developed in this research were anticipated to be applied in real wastewater treatment, contributing to further comprehend the mechanisms of element doping and defect modification in g-C3N4 activating PMS, and providing new insights for the design of PMS-activating catalysts.
金属基催化剂可用于高效活化过一硫酸盐（PMS），但不可避免地会受到金属离子浸出的影响。能够活化 PMS 的无金属氮化石墨碳（g-C3N4）材料更有利于实用水处理。本研究合成了具有 N 缺陷和 P 掺杂的 g-C3N4（CN-NP），它主要产生单线态氧（1O2），CN-NP/PMS/Vis 反应体系在 60 分钟内可去除 97% 的 4-CP（4-氯苯酚）。通过淬灭实验和电子自旋共振（ESR）测试确定了活性物种，并通过反应过程中 PMS 的浓度变化进一步验证了主要活性物种的来源。实验和理论计算证实，N 缺陷的引入导致了光诱导电子-空穴对的分离，提高了光催化活性。值得注意的是，密度泛函理论（DFT）揭示了 N 缺陷和 P 掺杂都是缺电子位点，而 P 掺杂是 PMS 的主要吸附位点，可促进 PMS 失电子生成 1O2。此外，本研究开发的催化剂有望应用于实际废水处理，有助于进一步理解 g-C3N4 中元素掺杂和缺陷修饰激活 PMS 的机理，并为设计 PMS 激活催化剂提供新的见解。
{"title":"N-defects and P-doping synergistically promote carbon nitride photocatalytic activation of peroxomonosulfate: Triggering the selective generation of 1O2 to degrade 4-Chlorophenol","authors":"Yuan Zhang, Kangping Cui, Xueyan Liu, Minshu Cui, Xing Chen, Yuchao Tang, Haiyang Li","doi":"10.1016/j.seppur.2024.130545","DOIUrl":"https://doi.org/10.1016/j.seppur.2024.130545","url":null,"abstract":"Metal-based catalyst could be used for efficient peroxymonosulfate (PMS) activation, but inevitably suffered from metal ion leaching. Metal-free graphitic carbon nitride (g-C<sub>3</sub>N<sub>4</sub>) materials that can activate PMS are more conducive for practical water treatment. In this study, g-C<sub>3</sub>N<sub>4</sub> with both N-defects and P-doping (CN-NP) was synthesized, which mainly produce singlet oxygen (<sup>1</sup>O<sub>2</sub>), and 97 % of 4-CP (4-Chlorophenol) was removed by CN-NP/PMS/Vis reaction system within 60 min. The active species was identified by quenching experiments and electron spin resonance (ESR) tests, and the origin of mainly active species was further verified by the concentration change of PMS during the reaction. It was verified by experiments and theoretical calculations that the introduction of N-defects led to the separation of photoinduced electron-hole pairs and improved photocatalytic activity. Notably, density functional theory (DFT) revealed that both N-defects and P-doping are electron-deficient sites, and P-doping acts as the main PMS adsorption site to promote the loss of electrons from PMS to generate <sup>1</sup>O<sub>2</sub>. In addition, the catalysts developed in this research were anticipated to be applied in real wastewater treatment, contributing to further comprehend the mechanisms of element doping and defect modification in g-C<sub>3</sub>N<sub>4</sub> activating PMS, and providing new insights for the design of PMS-activating catalysts.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"18 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642719","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}
Activating peroxymonosulfate (PMS) to generate sulfate radicals (SO4·-) is an effective method for water purification. An efficient, low-cost, and easily synthesized catalyst ensures decontamination performance and practical application feasibility. In this work, oxygen vacancy-enriched magnetic Co0.2FeOx was synthesized by isomorphous substitution of Fe3+ with Co2+ in α-FeOOH and employed to activate PMS to degrade iohexol, an iodinated X-ray contrast media widely detected in water. Co0.2FeOx exhibited higher performance than previously reported transition metal oxides. Iohexol could be effectively degraded in the Co0.2FeOx-catalyzed system from pH 3.5 to 10.5 compared to PMS oxidation alone. In situ tests in D2O and H2O using ATR-FTIR spectra inferred that the oxygen vacancies on the Co0.2FeOx surface could facilitate the formation of surface hydroxyl groups, which could complex HSO5- to form Me-(OH)-OSO3-. Electron transfer in the inner complex via the redox of Co(II)/Co(III) and Fe(III)/Fe(II) caused the breakage of the O-O bonds, thus promoting free radical generation. ESR spectra identified SO4·- and ·OH as the predominant active species. This study suggests new ideas for the synthesis of efficient catalysts and elucidates new insights into the interfacial mechanism of PMS activation
{"title":"Improving peroxymonosulfate activation via surface-constructed oxygen vacancies on Co0.2FeOx for durable water decontamination","authors":"Pengwei Yan, Ziliang Zhang, Wenyu Wu, Zhonglin Chen, Lianpeng Sun, Fang Ma, Jimin Shen, Jing Kang, Yabin Li, Yizhen Cheng, Binyuan Wang","doi":"10.1016/j.seppur.2024.130574","DOIUrl":"https://doi.org/10.1016/j.seppur.2024.130574","url":null,"abstract":"Activating peroxymonosulfate (PMS) to generate sulfate radicals (SO<sub>4</sub><sup>·-</sup>) is an effective method for water purification. An efficient, low-cost, and easily synthesized catalyst ensures decontamination performance and practical application feasibility. In this work, oxygen vacancy-enriched magnetic Co<sub>0.2</sub>FeO<sub>x</sub> was synthesized by isomorphous substitution of Fe<sup>3+</sup> with Co<sup>2+</sup> in α-FeOOH and employed to activate PMS to degrade iohexol, an iodinated X-ray contrast media widely detected in water. Co<sub>0.2</sub>FeO<sub>x</sub> exhibited higher performance than previously reported transition metal oxides. Iohexol could be effectively degraded in the Co<sub>0.2</sub>FeO<sub>x</sub>-catalyzed system from pH 3.5 to 10.5 compared to PMS oxidation alone. In situ tests in D<sub>2</sub>O and H<sub>2</sub>O using ATR-FTIR spectra inferred that the oxygen vacancies on the Co<sub>0.2</sub>FeO<sub>x</sub> surface could facilitate the formation of surface hydroxyl groups, which could complex HSO<sub>5</sub><sup>-</sup> to form Me-(OH)-OSO<sub>3</sub><sup>-</sup>. Electron transfer in the inner complex via the redox of Co(II)/Co(III) and Fe(III)/Fe(II) caused the breakage of the O-O bonds, thus promoting free radical generation. ESR spectra identified SO<sub>4</sub><sup>·-</sup> and ·OH as the predominant active species. This study suggests new ideas for the synthesis of efficient catalysts and elucidates new insights into the interfacial mechanism of PMS activation","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"7 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642716","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}
This study presents an efficient approach to selectively upgrade coal-based humic acid (CBHA) from depolymerized lignite to fulvic acid (FA) while co-producing H2 via electro-catalytic oxidation using NiCoOOH supported on nickel foam (NF) as the anode. In comparison, the prepared NiCoOOH/NF demonstrated a superior electro-catalytic oxidation performance than NiCuOOH/NF, NF, and Pt. The results showed that a 50.30 % conversion of CBHA with FA selectivity exceeding 85 % was achieved by conducting electrolysis in 1 mol/L KOH at 1.42 V (vs. RHE) for 2 h, meanwhile H2 was produced with a Faradaic efficiency (FE) of 98 % at the cathode. Following this, a series of analytical techniques including SEM, XRD, CV, and LSV were utilized to characterize the structure and electrochemical performances of NiCoOOH/NF. Based on the results from ESI FT-ICR/MS, MALDI TOF/MS, and 13C NMR, the degradation of CBHA involves oxidative ring-opening of aromatic nuclei, which leads to the formation of polycarboxylic acids, including aromatic and aliphatic carboxylic acids. Overall, this study introduces a highly efficient and selective electro-oxidation upgrading strategy, presenting a promising method for the low-carbon and high-value utilization of lignite and its CBHA.
{"title":"Selective upgrading coal-based humic acid to fulvic acid through electrochemical oxidation coupled with hydrogen production","authors":"Jining Zhou, Haiyan Ge, Zhicai Wang, Chunxiu Pan, Xiaobiao Yan, Zhanku Li, Weidong Zhang, Honglei Yan, Jingchong Yan, Shibiao Ren, Zhiping Lei, Hengfu Shui","doi":"10.1016/j.seppur.2024.130566","DOIUrl":"https://doi.org/10.1016/j.seppur.2024.130566","url":null,"abstract":"This study presents an efficient approach to selectively upgrade coal-based humic acid (CBHA) from depolymerized lignite to fulvic acid (FA) while co-producing H<sub>2</sub> via electro-catalytic oxidation using NiCoOOH supported on nickel foam (NF) as the anode. In comparison, the prepared NiCoOOH/NF demonstrated a superior electro-catalytic oxidation performance than NiCuOOH/NF, NF, and Pt. The results showed that a 50.30 % conversion of CBHA with FA selectivity exceeding 85 % was achieved by conducting electrolysis in 1 mol/L KOH at 1.42 V (vs. RHE) for 2 h, meanwhile H<sub>2</sub> was produced with a Faradaic efficiency (FE) of 98 % at the cathode. Following this, a series of analytical techniques including SEM, XRD, CV, and LSV were utilized to characterize the structure and electrochemical performances of NiCoOOH/NF. Based on the results from ESI FT-ICR/MS, MALDI TOF/MS, and <sup>13</sup>C NMR, the degradation of CBHA involves oxidative ring-opening of aromatic nuclei, which leads to the formation of polycarboxylic acids, including aromatic and aliphatic carboxylic acids. Overall, this study introduces a highly efficient and selective electro-oxidation upgrading strategy, presenting a promising method for the low-carbon and high-value utilization of lignite and its CBHA.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"165 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642760","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 : 2024-11-16DOI: 10.1016/j.seppur.2024.130551
Lixian Wang, Lizhi Zhao, Xianglong Xiao, Xiaofu Wang, Jiayi Cao, Hui Ye, Hong Li, Yuzhong Zhang
Wastewater discharged from the textile industry contains large amounts of dyes and salts, causing serious pollution to the environment. Loose nanofiltration (LNF) membranes offer a promising solution for dye/salt separation. However, membrane fouling is a critical issue affecting the membrane performance. Here, polyether amine (PEA) is used as the aqueous monomer for interfacial polymerization to prepare a polyamide (PA) LNF membrane, and peroxidase-like Cu-FeTCPP nanosheets are embedded into the PA layer to develop the Nanozyme@PA membrane. The nanozyme-incorporated membrane has a thinner and enhanced porous active layer than PA membrane, resulting in higher water permeance (maximum of 80.7 L·m−2·h−2·bar−1), notable rejection of dyes (CR, >99.2 %) but low rejection of inorganic ions (NaCl, <6.4 %). The optimum dye/salt separation factor of Nanozyme@PA reaches 218.7. The loaded nanozyme can catalyze the degradation of dyes adsorbed on the membrane surface in the presence of hydrogen peroxide within 10 min, without the need for special operation, enabling the recovery of water permeance. This nanozyme functionalized LNF membrane with good permeability, selectivity and self-cleaning offers an efficient approach to dye wastewater treatment as well as an insight for membrane fabrication assisted by two-dimensional nanozyme.
纺织业排放的废水中含有大量染料和盐分，对环境造成严重污染。松散纳滤膜（LNF）为染料/盐分离提供了一种前景广阔的解决方案。然而，膜结垢是影响膜性能的一个关键问题。在此，使用聚醚胺（PEA）作为界面聚合的水性单体制备聚酰胺（PA）LNF 膜，并将过氧化物酶类 Cu-FeTCPP 纳米片嵌入 PA 层，开发出 Nanozyme@PA 膜。与 PA 膜相比，加入纳米酶的膜具有更薄和更多孔的活性层，因此透水性更高（最大值为 80.7 L-m-2-h-2-bar-1），对染料（CR，99.2%）的抑制效果显著，但对无机离子（NaCl，6.4%）的抑制效果较低。Nanozyme@PA 的最佳染料/盐分离因子达到 218.7。在过氧化氢存在的情况下，负载的纳米酶可在 10 分钟内催化降解吸附在膜表面的染料，无需特殊操作，即可恢复透水性。这种纳米酶功能化的 LNF 膜具有良好的渗透性、选择性和自洁性，为染料废水处理提供了一种有效的方法，也为二维纳米酶辅助膜的制造提供了启示。
{"title":"Two-dimensional Cu-FeTCPP nanozyme incorporated loose nanofiltration membrane with self-cleaning property for dye/salt separation","authors":"Lixian Wang, Lizhi Zhao, Xianglong Xiao, Xiaofu Wang, Jiayi Cao, Hui Ye, Hong Li, Yuzhong Zhang","doi":"10.1016/j.seppur.2024.130551","DOIUrl":"https://doi.org/10.1016/j.seppur.2024.130551","url":null,"abstract":"Wastewater discharged from the textile industry contains large amounts of dyes and salts, causing serious pollution to the environment. Loose nanofiltration (LNF) membranes offer a promising solution for dye/salt separation. However, membrane fouling is a critical issue affecting the membrane performance. Here, polyether amine (PEA) is used as the aqueous monomer for interfacial polymerization to prepare a polyamide (PA) LNF membrane, and peroxidase-like Cu-FeTCPP nanosheets are embedded into the PA layer to develop the Nanozyme@PA membrane. The nanozyme-incorporated membrane has a thinner and enhanced porous active layer than PA membrane, resulting in higher water permeance (maximum of 80.7 L·m<sup>−2</sup>·h<sup>−2</sup>·bar<sup>−1</sup>), notable rejection of dyes (CR, >99.2 %) but low rejection of inorganic ions (NaCl, <6.4 %). The optimum dye/salt separation factor of Nanozyme@PA reaches 218.7. The loaded nanozyme can catalyze the degradation of dyes adsorbed on the membrane surface in the presence of hydrogen peroxide within 10 min, without the need for special operation, enabling the recovery of water permeance. This nanozyme functionalized LNF membrane with good permeability, selectivity and self-cleaning offers an efficient approach to dye wastewater treatment as well as an insight for membrane fabrication assisted by two-dimensional nanozyme.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"21 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642718","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}
A concurrent approach, which allows for determining multi-component equilibrium isotherms and designing a multi-component adsorption process within a realistic amount of time and effort, is demonstrated for the first time in a moving bed process using an amine-impregnated solid adsorbent in the presence of CO2 and H2O. The proposed approach extracts measurement points for the binary isotherms from the temperature and partial pressure regions that exist in the optimized process from all potential combinations of CO2 partial pressure, H2O partial pressure, and temperature. At the extracted points, the equilibrium adsorption amounts were measured experimentally to obtain multi-component adsorption amount data, with which the binary isotherm parameters were determined by the Tikhonov regularization. The accuracy of the equilibrium isotherm was further improved iteratively by repeating the steps described above. The proposed approach enables us to determine the binary interactions parameters in the isotherm model reducing the multi-component measurement points only to 12, while obtaining the optimized process operation at the same time.
{"title":"A concurrent approach for determining binary isotherm and optimizing moving bed adsorber for solid amine adsorbent in the coexistence of CO2 and H2O","authors":"Takeshi Okumura, Takahiro Yamaguchi, Yoshiaki Kawajiri","doi":"10.1016/j.seppur.2024.130567","DOIUrl":"https://doi.org/10.1016/j.seppur.2024.130567","url":null,"abstract":"A concurrent approach, which allows for determining multi-component equilibrium isotherms and designing a multi-component adsorption process within a realistic amount of time and effort, is demonstrated for the first time in a moving bed process using an amine-impregnated solid adsorbent in the presence of CO<sub>2</sub> and H<sub>2</sub>O. The proposed approach extracts measurement points for the binary isotherms from the temperature and partial pressure regions that exist in the optimized process from all potential combinations of CO<sub>2</sub> partial pressure, H<sub>2</sub>O partial pressure, and temperature. At the extracted points, the equilibrium adsorption amounts were measured experimentally to obtain multi-component adsorption amount data, with which the binary isotherm parameters were determined by the Tikhonov regularization. The accuracy of the equilibrium isotherm was further improved iteratively by repeating the steps described above. The proposed approach enables us to determine the binary interactions parameters in the isotherm model reducing the multi-component measurement points only to 12, while obtaining the optimized process operation at the same time.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"37 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642712","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 : 2024-11-16DOI: 10.1016/j.seppur.2024.130561
Yanjia Zhou, Xiaodong Tang, Dayong Qing, Jingjing Li, Hong Wang
Lithium (Li) is a core strategic metal in the new energy industry. Due to its wide range of applications in various fields, the demand from the resource market is growing year by year. At present, Li is mostly extracted from lithium minerals (solid lithium ore and liquid lithium ore), seawater and spent lithium-ion batteries (LIBs). This paper focuses on the lithium extraction process of various lithium resources, expounds its reaction mechanism and application performance, and puts forward the possible future development direction. The extraction of lithium from solid lithium ores by the acid process has good practical applications but poor environmental sustainability. Additionally, the proportion of lithium resources of liquid lithium ore (brine) is greater than that of solid lithium ore, and extracting lithium from brine is the most valuable choice at present. The Li content in the brine is typically low. Lithium extraction with inorganic adsorbent is the most advanced method at present. Different techniques include evaporative crystallization, precipitation, solvent extraction, adsorption with organic and biological adsorbent, membrane separation, and electrochemical methods. However, most of the technologies with favorable economic benefits and high efficiency are still difficult to achieve large-scale industrialization. Therefore, it is still a great challenge to develop an economical, environmentally friendly, efficient and practical technology for extracting lithium from brine. Furthermore, with the rise and vigorous development of the LIBs market, the treatment and recycling of spent LIBs has become a major problem. According to the research, it is feasible to extract lithium from spent LIBs and achieve industrialization and recycling. Therefore, research on lithium extraction from spent LIBs is also the key to increasing the supply of lithium resources and achieving resource recycling.
{"title":"Research progress of technology of lithium extraction","authors":"Yanjia Zhou, Xiaodong Tang, Dayong Qing, Jingjing Li, Hong Wang","doi":"10.1016/j.seppur.2024.130561","DOIUrl":"https://doi.org/10.1016/j.seppur.2024.130561","url":null,"abstract":"Lithium (Li) is a core strategic metal in the new energy industry. Due to its wide range of applications in various fields, the demand from the resource market is growing year by year. At present, Li is mostly extracted from lithium minerals (solid lithium ore and liquid lithium ore), seawater and spent lithium-ion batteries (LIBs). This paper focuses on the lithium extraction process of various lithium resources, expounds its reaction mechanism and application performance, and puts forward the possible future development direction. The extraction of lithium from solid lithium ores by the acid process has good practical applications but poor environmental sustainability. Additionally, the proportion of lithium resources of liquid lithium ore (brine) is greater than that of solid lithium ore, and extracting lithium from brine is the most valuable choice at present. The Li content in the brine is typically low. Lithium extraction with inorganic adsorbent is the most advanced method at present. Different techniques include evaporative crystallization, precipitation, solvent extraction, adsorption with organic and biological adsorbent, membrane separation, and electrochemical methods. However, most of the technologies with favorable economic benefits and high efficiency are still difficult to achieve large-scale industrialization. Therefore, it is still a great challenge to develop an economical, environmentally friendly, efficient and practical technology for extracting lithium from brine. Furthermore, with the rise and vigorous development of the LIBs market, the treatment and recycling of spent LIBs has become a major problem. According to the research, it is feasible to extract lithium from spent LIBs and achieve industrialization and recycling. Therefore, research on lithium extraction from spent LIBs is also the key to increasing the supply of lithium resources and achieving resource recycling.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"29 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642676","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 : 2024-11-16DOI: 10.1016/j.seppur.2024.130565
Shenyan Xu, Hongxiang Chu, Xin Qin, Bei Jiang, Ruofan Li, Taikang Jia, Wenjing Wang, Chunyu Che, Yongsheng Wu, Ling Zhang, Chuanqi Zhang, Wenzhong Wang
The photocatalytic production of hydrogen peroxide from water and oxygen using solar energy presents a promising approach. Nevertheless, challenges persist regarding the efficiency of this process and the clarification of the underlying catalytic mechanisms. In this study, we synthesized a donor-acceptor type photocatalyst, modified resorcinol-formaldehyde resin. FT-IR and XPS analyses confirmed the successful incorporation of an additional electron donor unit, N, N-dimethylaniline, which interacts with the electron acceptor unit to facilitate the directed migration of photogenerated electrons. Furthermore, this modification creates an electron-rich carbonyl active center, enhancing its capacity to adsorb and reduce O2, thereby improving the photocatalytic production of H2O2. In situ EPR and DRIFT analyses identified key intermediates, substantiating a two-step, single-electron oxygen reduction pathway and providing insights into the catalytic mechanism. Importantly, without the use of sacrificial agents or additional aeration, the photocatalytic production rate of H2O2 reached 22.8 μmol·h−1, underscoring its potential as an effective photocatalyst. This study elucidates the reaction mechanism during the photocatalytic process, offering valuable insights for future material design aimed at enhancing hydrogen peroxide production rates.
{"title":"Boosting photocatalytic H2O2 production by incorporating extra electron-donor group over resorcinol-formaldehyde resin","authors":"Shenyan Xu, Hongxiang Chu, Xin Qin, Bei Jiang, Ruofan Li, Taikang Jia, Wenjing Wang, Chunyu Che, Yongsheng Wu, Ling Zhang, Chuanqi Zhang, Wenzhong Wang","doi":"10.1016/j.seppur.2024.130565","DOIUrl":"https://doi.org/10.1016/j.seppur.2024.130565","url":null,"abstract":"The photocatalytic production of hydrogen peroxide from water and oxygen using solar energy presents a promising approach. Nevertheless, challenges persist regarding the efficiency of this process and the clarification of the underlying catalytic mechanisms. In this study, we synthesized a donor-acceptor type photocatalyst, modified resorcinol-formaldehyde resin. FT-IR and XPS analyses confirmed the successful incorporation of an additional electron donor unit, N, N-dimethylaniline, which interacts with the electron acceptor unit to facilitate the directed migration of photogenerated electrons. Furthermore, this modification creates an electron-rich carbonyl active center, enhancing its capacity to adsorb and reduce O<sub>2</sub>, thereby improving the photocatalytic production of H<sub>2</sub>O<sub>2</sub>. <em>In situ</em> EPR and DRIFT analyses identified key intermediates, substantiating a two-step, single-electron oxygen reduction pathway and providing insights into the catalytic mechanism. Importantly, without the use of sacrificial agents or additional aeration, the photocatalytic production rate of H<sub>2</sub>O<sub>2</sub> reached 22.8 μmol·h<sup>−1</sup>, underscoring its potential as an effective photocatalyst. This study elucidates the reaction mechanism during the photocatalytic process, offering valuable insights for future material design aimed at enhancing hydrogen peroxide production rates.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"75 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642677","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}
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