Separation and Purification Technology最新文献

{"title":"Glycerol-regulated blend membranes of polyether sulfone (PES) and sulfonated polyether sulfone (SPES) for the separation of dye and salt","authors":"Yutong Qin ,&nbsp;Yingbo Chen ,&nbsp;Yongyan Wu ,&nbsp;Haowei Bai ,&nbsp;Yongxiang Shi","doi":"10.1016/j.seppur.2026.137168","DOIUrl":"10.1016/j.seppur.2026.137168","url":null,"abstract":"<div><div>Currently, in the field of dye wastewater treatment, loose nanofiltration membranes generally suffer from low flux and are prone to fouling. Moreover, compared to ultrafiltration membranes, they exhibit a certain retention rate for salts, which is not conducive to the efficient separation of dyes and salts. Therefore, there is an urgent need to develop membranes with high flux and high efficiency in separating dyes from salts. In this study, a phase-inversion-engineered blend membrane comprising polyether sulfone (PES) and sulfonated polyether sulfone (SPES) is reported, which forms a hydrophilic surface layer and compositionally graded substructure. Glycerol was used to modify the membrane, acting as both a lubricant and pore size regulator. By forming hydrogen bonds (intermolecular forces) with the polymer, it improved film formation properties and pore structure, enhanced hydrophilicity, and further increased water flux. Scanning electron microscopy, surface zeta potential, and fully automatic water contact angle test were used to characterize the surface and cross-sectional morphology, surface electronegativity, and hydrophilic of the loose nanofiltration membrane. The pure water flux of the membrane with a solid content of 35% and glycerol addition of 0.1 wt% increase from the original 65.31 L m⁻²·h⁻¹·bar⁻¹ to 104.16 L m⁻²·h⁻¹·bar⁻¹. It achieves near-complete rejection (&gt;96%) of multiple dyes including Congo red, Acid Blue 83, Coomassie Brilliant Blue G-250, and Rose Bengal, while maintaining ultralow salt rejection (Na₂SO₄: 16.86%; NaCl: 2.86%; MgSO₄: 2.42%; MgCl₂: 0.26%)—indicating effective size and charge-based selectivity. This work establishes a simple yet effective glycerol-mediated strategy for fabricating high-flux blend membranes with precise molecular discrimination, offering great potential for dye desalination and resource recovery in textile effluent treatment.</div></div>","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"392 ","pages":"Article 137168"},"PeriodicalIF":9.0,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172348","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}

{"title":"Research and development of eco-friendly high-temperature and salt-resistant filtrate reducers for minimizing drilling fluid loss and environmental pollution","authors":"You Guo ,&nbsp;Yinbo He ,&nbsp;Mingliang Du ,&nbsp;Guancheng Jiang ,&nbsp;Qingchen Wang ,&nbsp;Qin Zhang","doi":"10.1016/j.seppur.2026.137209","DOIUrl":"10.1016/j.seppur.2026.137209","url":null,"abstract":"<div><div>Filtrate reducers are essential drilling-fluid additives that mitigate formation damage from fluid invasion. With the depletion of shallow resources, drilling-fluid applications are increasingly directed toward deep reservoirs that present harsh high-temperature and high-salinity conditions. Conventional high-temperature and salt-resistant filtrate reducers often generate persistent, poorly degradable residues after prolonged heating, whereas eco-friendly alternatives are more degradable but generally lack sufficient thermal and salt tolerance. In this study, an eco-friendly filtrate reducer (AAPT), synthesized from multiple functional monomers, was prepared and systematically evaluated. Environmental assessment indicates that AAPT is non-toxic and biodegradable (EC50 = 200,000 mg/L; BOD5/CODCr = 0.41). Its molecular weight decreases to 987.98 Da after 72 h at 200 °C, with degradation products readily assimilated by plants (wheat germination rate = 90.5% etc., comparable to low-viscosity polyanionic cellulose, PAC<img>Lv). Performance tests demonstrate that AAPT maintains stable filtration control for more than four days at 200 °C; after 96 h, the high-temperature high-pressure (HTHP) fluid loss remains as low as 27 mL, more than 86% lower than PAC-Lv and carboxymethyl starch (CMS). In addition, AAPT remains effective under a salinity level of 15%. Mechanistic studies suggest that its crosslinked structure improves thermal stability, while multipoint adsorption and amphoteric polyelectrolyte effects enhance bentonite hydration, dispersion, and salt resistance, thereby facilitating the formation of a dense, smooth mud cake that minimizes filtrate drain away. Finally, AAPT integrates fluid-loss control under extreme conditions with environmental compatibility, offering a promising strategy for next-generation sustainable drilling-fluid additives in deep and ultra-deep energy exploration.</div></div>","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"392 ","pages":"Article 137209"},"PeriodicalIF":9.0,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146146160","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}

{"title":"FeCl3/KOH-modified digestate biochar for ciprofloxacin removal: Fe-O coordination-promoted adsorption mechanism and sustainability assessment","authors":"Zihao Wei ,&nbsp;Qian Wu ,&nbsp;Shiyu Fang ,&nbsp;Xiang Zou ,&nbsp;Ran Yu ,&nbsp;Jiashun Cao ,&nbsp;Lianghu Su ,&nbsp;Weijing Liu ,&nbsp;Song Cheng ,&nbsp;Jingyang Luo","doi":"10.1016/j.seppur.2026.137177","DOIUrl":"10.1016/j.seppur.2026.137177","url":null,"abstract":"<div><div>Digestate-derived biochar (BC) and an FeCl₃/KOH-modified biochar (FKBC) were evaluated for ciprofloxacin (CIP) removal from nutrient-rich wastewater. FeCl₃/KOH modification increased the specific surface area from 76.3 to 176.1 m²/g and introduced abundant oxygen-containing functional groups with dispersed Fe<img>O coordination sites. Consequently, FKBC exhibited a Langmuir adsorption capacity of 117.93 mg/g, representing a 91.1% enhancement over pristine BC. Adsorption kinetics of FKBC were well described by the pseudo-second-order model (R² ≈ 0.99), with higher rate constants and initial adsorption rates, indicating accelerated chemisorption. FKBC further enabled simultaneous removal of ammonium and phosphate (∼60% at 20–120 mg/L). Adsorption was pH-dependent, favoring acidic conditions. XPS/FTIR analyses combined with density functional theory (DFT) calculations revealed that CIP adsorption is primarily governed by inner-sphere Fe<img>O coordination and carboxylate complexation, with carbonyl anchoring and π-π interactions contributing at higher surface coverage. Stable Fe 2p features before and after adsorption indicate reversible surface coordination without alteration of iron chemical states, supporting low iron-leaching risk. A ranking efficiency product (REP) analysis yielded an overall sustainability score of 85%, highlighting FKBC as an efficient and sustainable adsorbent for antibiotic remediation and resource-oriented digestate valorization.</div></div>","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"392 ","pages":"Article 137177"},"PeriodicalIF":9.0,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146153690","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}

{"title":"Aqueous hydrotrope-based green extraction of alkaloids: insights into mechanism and experimentation with Coptis chinensis","authors":"Nhan Trong Le ,&nbsp;The-Huan Tran ,&nbsp;Vy Khanh Thi Nguyen,&nbsp;Tuong Cat Chau Mai,&nbsp;Hoai Thi Nguyen","doi":"10.1016/j.seppur.2026.137195","DOIUrl":"10.1016/j.seppur.2026.137195","url":null,"abstract":"<div><div>The search for environmentally benign solvents has become a central task in natural product research, as conventional organic solvents remain problematic for both safety and sustainability. Hydrotropes (HTs) are emerging as an attractive alternative because they can significantly increase the aqueous solubility of poorly soluble compounds. This study explored the use of aqueous HT solutions for alkaloid recovery, exemplified by the case of <em>Coptis chinensis</em>. Initial screening highlighted sodium salicylate (SS) as a particularly effective solvent, affording higher yields of coptisine, palmatine, berberine, and total alkaloids than conventional or other green solvents. Through response surface methodology, the optimum conditions were identified (46.4% SS, liquid–solid ratio 26.7 mL/g, 21.8 min, 60 °C), under which the yields of coptisine, palmatine, berberine, and total alkaloids reached 1.85%, 1.39%, 8.97%, and 15.57%, respectively. Mechanistic analyses, combining electrostatic potential mapping, interaction region indicator plots, and molecular dynamics simulations, revealed that the strong performance of SS stems from cooperative anion–Cδ⁺ electrostatic interactions together with dispersion forces and weak hydrogen bonding. The extraction followed a second-order kinetic model (<em>E</em>_<em>a</em> = 26.14 kJ/mol), suggesting contributions from both dissolution and diffusion. Importantly, alkaloids were efficiently recovered with macroporous resins (best with HPD-400), and both SS and the resins could be reused for at least five cycles with negligible efficiency loss. Sustainability was further quantitatively assessed using the AGREEprep metric. Taken together, these findings establish aqueous SS as a practical, reusable, and environmentally responsible solvent system for sustainable alkaloid extraction, with mechanistic validation demonstrated for berberine.</div></div>","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"392 ","pages":"Article 137195"},"PeriodicalIF":9.0,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146153706","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}

{"title":"Fabrication and properties of air filter materials with fluffy multi-scale micro/nano bimodal fibers via multi-nozzle solution blow spinning","authors":"Pengqi Shi ,&nbsp;Gaohui Fan ,&nbsp;Wanli Yue ,&nbsp;Yanru Bai ,&nbsp;Xu Zhao ,&nbsp;Hao Guo ,&nbsp;Qiaomei Zhang ,&nbsp;Bowei Liu ,&nbsp;Guorui Zhang ,&nbsp;Jingyi Sun ,&nbsp;Xuling Jin ,&nbsp;Baokang Yu ,&nbsp;Rongwu Wang ,&nbsp;Jianxin He","doi":"10.1016/j.seppur.2026.137183","DOIUrl":"10.1016/j.seppur.2026.137183","url":null,"abstract":"<div><div>To address the challenge of balancing high efficiency, low resistance, and long-term stability in fibrous filter materials, this study proposes an innovative parallel-integrated spinning strategy. By combining solution blow spinning and electrostatic solution blow spinning units in situ, a three-dimensional fluffy micro/nano-bimodal fiber composite filter material was successfully prepared in a single step. This method achieves the synchronous formation and uniform interweaving of a microfiber skeleton and a nanofiber filtration network, while allowing precise optimization of the material's pore size distribution and pore structure through adjustment of the spinning unit ratio. The results show that the prepared filter material exhibits a distinct bimodal fiber distribution, high porosity (&gt;92%), and strong hydrophobicity endowed by its micro-nano multi-scale rough structure. Among them, the filter prepared with a spinning unit ratio of 1 (WNfm1/1) demonstrates the optimal initial comprehensive filtration performance (99.648 ± 0.36% efficiency, quality factor of 0.03646 ± 0.0002 Pa⁻¹). In contrast, the filter prepared with a spinning unit ratio of 2 (WNfm2/1), benefiting from its more open pore structure, exhibits higher dust-holding capacity (29.54 g/m²), longer service life (34 days), and excellent stability in long-term tests, revealing the balance between initial efficiency and long-term, low-resistance operation. Combined with microstructural evolution observations and numerical simulations, the research elucidates the synergistic mechanism of micro- and nanofibers in depth filtration. The material also possesses good mechanical resilience and thermal stability. This work provides a novel preparation strategy and theoretical foundation for the development of high-performance and sustainable air filter materials.</div></div>","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"392 ","pages":"Article 137183"},"PeriodicalIF":9.0,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146153363","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}

{"title":"Enriching trace protein peptides from extract liquid with foaming deep eutectic solvent (FDES)-loaded effervescent discs","authors":"Xinlu Li ,&nbsp;Yong Cao ,&nbsp;Jie Tang ,&nbsp;Yihan Zhao ,&nbsp;Subhan Mahmood ,&nbsp;Shun Yao","doi":"10.1016/j.seppur.2026.137181","DOIUrl":"10.1016/j.seppur.2026.137181","url":null,"abstract":"<div><div>Snake shedding skin (snake molt) exhibits good potential for nutritional and functional applications, yet current methods for sustainable and efficient extraction of protein peptides from such an animal raw material are relatively limited. Herein, we reported novel foaming deep eutectic solvents (FDES) loaded effervescent discs for enriching target protein peptides in hydrolyzed extract of snake molt. Two kinds of natural sweeteners were used in the FDESs, which played an important role on foam stabilization and endowed FDESs with higher biocompatibility. After comprehensive characterizations, the discs exhibited good properties and expected forming performance. Under the ideal conditions, the effervescent discs enriched 91.40% protein peptides within 4 min, which was much higher than the alcohol precipitation method (40.12% within 3 d) and the aqueous two-phase system (80.67% within 1 h). Green assessment and scale-up experiments were also carried out for possible actual applications. Finally, the enriched product was analyzed by comprehensive physicochemical characterizations confirmed structural integrity and performance. The developed method offers a rapid, sustainable approach for obtaining peptides from natural products.</div></div>","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"392 ","pages":"Article 137181"},"PeriodicalIF":9.0,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146135565","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}

{"title":"Nanoporous fibrous 3D solar evaporator for efficient freshwater generation and salt recovery","authors":"Mojtaba Ebrahimian Mashhadi,&nbsp;Md. Mehadi Hassan,&nbsp;Ningxin Chen,&nbsp;Ruijie Yang,&nbsp;Qingye Lu","doi":"10.1016/j.seppur.2026.137162","DOIUrl":"10.1016/j.seppur.2026.137162","url":null,"abstract":"<div><div>Solar-driven interfacial evaporators (SDIEs) have advanced sustainable desalination by enabling freshwater production and salt harvesting from brines. Here, electrospun cellulose acetate (CA) films with aligned nanoporous fibers are rolled into a 3D cylinder and partially coated with a carbon black/poly(vinyl alcohol) (CB/PVA) photothermal layer to create an environmentally-friendly SDIE for concurrent desalination and salt recovery. The evaporator achieves a high evaporation rate of 4.44 kg m⁻² h⁻¹ under 1 sun, corresponding to a photothermal conversion efficiency of 107.3% based on equivalent evaporation enthalpy. This performance is ascribed to reduced vaporization enthalpy from material-water interactions and nanoporous structures, along with cold evaporation-induced environmental energy harvesting. Under 1 sun, the SDIE stably treats brines of 3.5–20 wt% salinity with edge-preferential salt crystallization due to its fibrous microporous architecture. This feature allows gravity-assisted salt collection and durable function in 10 wt% NaCl for 10 days, maintaining average steam generation and salt harvesting rates of 4.71 kg m⁻² h⁻¹ and 3.21 kg m⁻² day⁻¹, respectively. Condensed waters from 3.5 wt% NaCl and simulated seawater exhibit high purity with significantly lower conductivities. The outdoor experiment also reveals the stable performance of the SDIE under actual conditions. Computational fluid dynamics (CFD) simulation further validates edge-preferential salt aggregation. This innovative device offers a promising route for simultaneous freshwater and salt collection from brines.</div></div>","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"392 ","pages":"Article 137162"},"PeriodicalIF":9.0,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146135574","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}

{"title":"Organic acid tailors anhydrous magnesium carbonate: DFT-guided dehydration mechanism and morphology engineering","authors":"Yahui Feng ,&nbsp;Jiajun Xu ,&nbsp;Jie Xu ,&nbsp;Li Gao ,&nbsp;Bingxin Liu ,&nbsp;Chao Zhang ,&nbsp;Shiai Xu ,&nbsp;Yunhua Lu","doi":"10.1016/j.seppur.2026.137211","DOIUrl":"10.1016/j.seppur.2026.137211","url":null,"abstract":"<div><div>Mineral carbonation into Anhydrous Magnesium Carbonate (AMC) is a promising pathway for permanent CO₂ storage, yet the strong hydration of Mg²⁺ hinders its precipitation under mild conditions. To overcome this limitation, organic acids (<span>l</span>-ascorbic acid (LA), citric acid (CA), malic acid (MA), and tartaric acid (TA)) are employed as dual-functional agents: carbon sources and hydration disruptors. Through combined density functional theory (DFT) calculations and experimental validation, it is revealed that organic acids weaken the hydration shell of [Mg(H₂O)₆]²⁺ by forming stable coordination bonds with Mg²⁺, significantly reducing the dehydration energy barrier (e.g., ΔG^‡₆-₅ decreased from 180.53 kJ/mol in H₂O to 76.71 kJ/mol for LA). Systematic hydrothermal synthesis demonstrates that LA enables high-purity AMC formation at 450 K, the widest temperature window among the tested acids. At the same time, TA requires ≥525 K. Crucially, each acid directs distinct AMC morphologies, hydrangea-like (LA), cubic (CA), layered (MA), and block-like (TA), attributed to site-specific adsorption on crystal surfaces. This work provides a molecular-level blueprint for overcoming the dehydration barrier in AMC synthesis and advances strategies for accelerating sustainable CO₂ mineralization.</div></div>","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"392 ","pages":"Article 137211"},"PeriodicalIF":9.0,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172229","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}

{"title":"Construction of hydrophilic PDMS/PEI gutter layer to fabricate ultrathin Pebax membrane for CO2 capture","authors":"Danjiao Shi,&nbsp;Kai Cheng,&nbsp;Meng Guo,&nbsp;Rong Xu,&nbsp;Tiandan Lu,&nbsp;Dongliang Jin,&nbsp;Shengshen Gu,&nbsp;Yang Pan,&nbsp;Jing Zhong","doi":"10.1016/j.seppur.2026.137170","DOIUrl":"10.1016/j.seppur.2026.137170","url":null,"abstract":"<div><div>Polydimethylsiloxane (PDMS) is extensively utilized as a gutter layer in thin-film composite membranes (TFC) owing to its exceptional gas permeability and mechanical robustness. However, the hydrophilic modification of PDMS is necessary to ensure the uniform coating of selective layer materials containing polar groups on the hydrophobic PDMS gutter layer surface. Conventional hydrophilic treatment such as plasma treatment or UV irradiation produces transient Si-OH groups but require controlled atmosphere or chemical grafting to maintain sustained hydrophilicity. To address these challenges, the inverted interfacial polymerization (IP) process (aqueous phase upper/organic phase down) was designed to construct the PDMS-polyethyleneimine (PEI) interpenetration network (IPN), so as called IP-IPN strategy. The anchored PEI segments endowed PDMS surface with superior hydrophilicity as the water contact angle decreased from 110^o to 67^o and the hydrophilicity was retained over 7 days. The introduction of glycerol as the thickener contributed significantly to tuning the PEI-TMC crosslinking process and improved the gas permeance effectively. The hydrophilic-modified PDMS membrane retained 87.9% of its original CO₂ permeance (9100 GPU). The permeance decline rate was much smaller than plasma treatment and UV irradiation which usually generate dense SiO_x layer. When integrated with an ultrathin Pebax selective layer (∼30 nm), the composite membrane exhibited exceptional CO₂/N₂ separation performance (CO₂ permeance: 2300 GPU; CO₂/N₂ selectivity: 31.5). This work offered a feasible pathway to achieve hydrophilic-modification of PDMS gutter layer, showing great potential in developing highly permeable membrane for efficient CO₂ capture.</div></div>","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"392 ","pages":"Article 137170"},"PeriodicalIF":9.0,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172393","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}

{"title":"The improvement of selective removal of nitrate using reactive cationic surfactant modified activated carbon in capacitive deionization","authors":"Yubo Zhao ,&nbsp;Yingyun Li ,&nbsp;Xiaofei Liu ,&nbsp;Silu Huo ,&nbsp;Jinfeng Fang ,&nbsp;Rupeng Liu ,&nbsp;Cuizhen Sun ,&nbsp;Linxu Xu ,&nbsp;Xue Shen ,&nbsp;Shuying Geng ,&nbsp;Jin Wang ,&nbsp;Kexun Li","doi":"10.1016/j.seppur.2026.137188","DOIUrl":"10.1016/j.seppur.2026.137188","url":null,"abstract":"<div><div>Nitrate (NO₃⁻) pollution in aquatic environments is a global problem of increasing concern. Capacitive deionization (CDI) exhibits remarkable potential for NO₃⁻ removal due to its advantages of cost-effectiveness and environmental benignity. However, traditional activated carbon (AC) suffers from low electrosorption capacity and poor NO₃⁻ selectivity in the presence of coexisting anions (e.g., Cl⁻). To address this challenge, this study proposes a new surface functionalization strategy using the reactive cationic surfactant. 3-chloro-2-hydroxypropyltrimethylammonium chloride (CHPTAC) was used as the representative to modify AC via covalent grafting, yielding RCS-functionalized AC (RCS-AC). Multiple material characterizations confirmed the successful incorporation of CHPTAC-derived groups onto the surface of AC, which not only reversed the inherent negative surface potential of AC but also notably improved its surface hydrophilicity. CDI experiments demonstrated that the covalent modification endowed RCS-AC with superior electrosorption performance compared to pristine AC while maintaining exceptional cyclic stability. In the single-component experiments, RCS-AC achieved a maximum NO₃⁻ adsorption capacity of 20.58 mg/g at 1.8 V according to Langmuir isotherm model. A high NO₃⁻/Cl⁻ selectivity coefficient of 5.75 was also obtained for RCS-AC at 0.8 V and retained at 2.47 upon voltage elevation to 1.8 V in the brine-component experiments, in contrast to the non-selective behavior of pristine AC. Density functional theory (DFT) calculations revealed that the enhanced adsorption and selective recognition of RCS-AC for NO₃⁻ was related to the multi-dimensional specific interactions between CHPTAC-derived groups and NO₃⁻, including strengthened electrostatic attraction, directional hydrogen bonding, and partial covalent interaction. This work offers a simple yet stable approach to enhance NO₃⁻ selectivity via RCS modification and provide experimental evidence for adaptability of RCS-AC in competitive ion environments.</div></div>","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"392 ","pages":"Article 137188"},"PeriodicalIF":9.0,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172383","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}