Pub Date : 2026-01-20DOI: 10.1016/j.watres.2026.125427
Chi Zhang , Pengfei Chen , Jiazhou He , Daoyuan Zu , Chia-Hung Hou , Yang Wang , Xiangtong Kong , Jinxing Ma
Nickel-ammonia chelated wastewater generated by electroplating and battery manufacturing is difficult to treat using conventional precipitation-based methods that require high chemical input and offer limited resource recovery. Here, we report a reagent-free dual-stage electrochemical membrane reactor that resolves the intrinsic pH-speciation mismatch between nickel removal and ammonia stripping. In the cathodic chambers, in situ generation of hydroxide ions dissociates nickel-ammonia complexes, enabling nickel recovery through electrodeposition and hydroxide precipitation, while anodically generated protons drive ammonia capture across a gas-permeable membrane. The dual-stage configuration independently optimized the pH conditions required for nickel and ammonia removal, reducing effluent Ni and NH4+-N concentrations to below 0.1 and 25 mg L−1, respectively, while producing reusable metallic Ni, β-Ni(OH)2, and ammonia solution. Life cycle assessment shows that although the dual-stage electrochemical process requires higher primary energy input than chemical precipitation, selective recovery of nickel and ammonia substantially lowers overall environmental damage. This work demonstrates a compact and sustainable electrochemical pathway for nickel-ammonia decomplexation and resource recovery, providing a circular-economy solution for metal-finishing and battery wastewater treatment.
电镀和电池制造过程中产生的镍氨螯合废水很难用传统的沉淀法处理,因为沉淀法需要大量的化学物质投入,而且资源回收率有限。在这里,我们报告了一个无试剂的双级电化学膜反应器,解决了镍去除和氨提之间固有的ph -形态不匹配。在阴极腔室中,原位生成的氢氧化物离子解离镍-氨配合物,通过电沉积和氢氧化物沉淀实现镍的回收,而阳极生成的质子驱动氨捕获通过透气膜。双级配置独立优化了除镍和除氨所需的pH条件,将出水Ni和NH4+-N浓度分别降至0.1和25 mg L - 1以下,同时生产可重复使用的金属Ni、β-Ni(OH)2和氨溶液。生命周期评价结果表明,虽然双阶段电化学过程比化学沉淀需要更高的一次能量输入,但选择性回收镍和氨大大降低了整体环境破坏。本研究展示了一种紧凑、可持续的镍氨分解和资源回收电化学途径,为金属精加工和电池废水处理提供了一种循环经济解决方案。
{"title":"Dual-stage electrochemical system enabling reagent-free nickel-ammonia decomplexation and resource recovery","authors":"Chi Zhang , Pengfei Chen , Jiazhou He , Daoyuan Zu , Chia-Hung Hou , Yang Wang , Xiangtong Kong , Jinxing Ma","doi":"10.1016/j.watres.2026.125427","DOIUrl":"10.1016/j.watres.2026.125427","url":null,"abstract":"<div><div>Nickel-ammonia chelated wastewater generated by electroplating and battery manufacturing is difficult to treat using conventional precipitation-based methods that require high chemical input and offer limited resource recovery. Here, we report a reagent-free dual-stage electrochemical membrane reactor that resolves the intrinsic pH-speciation mismatch between nickel removal and ammonia stripping. In the cathodic chambers, <em>in situ</em> generation of hydroxide ions dissociates nickel-ammonia complexes, enabling nickel recovery through electrodeposition and hydroxide precipitation, while anodically generated protons drive ammonia capture across a gas-permeable membrane. The dual-stage configuration independently optimized the pH conditions required for nickel and ammonia removal, reducing effluent Ni and NH<sub>4</sub><sup>+</sup>-N concentrations to below 0.1 and 25 mg L<sup>−</sup><sup>1</sup>, respectively, while producing reusable metallic Ni, β-Ni(OH)<sub>2</sub>, and ammonia solution. Life cycle assessment shows that although the dual-stage electrochemical process requires higher primary energy input than chemical precipitation, selective recovery of nickel and ammonia substantially lowers overall environmental damage. This work demonstrates a compact and sustainable electrochemical pathway for nickel-ammonia decomplexation and resource recovery, providing a circular-economy solution for metal-finishing and battery wastewater treatment.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"293 ","pages":"Article 125427"},"PeriodicalIF":12.4,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146014702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.watres.2026.125428
Cheng Chen , Yang Liu , Zheng Sun , Qiuwen Chen , Jianyun Zhang , Jinge Ma , Mengnan He
Future projections of cyanobacterial blooms is of great significance for ecological risks management in lakes under the combined influences of human activities and climate change. However, due to the lack of long-term data on cyanobacterial blooms and the uncertainty of future prediction models, our current understanding of continental-scale cyanobacterial blooms is still insufficient. This study developed an improved Commission Internationale de l´Eclairage (CIE)-based algorithm with multi-mask correction for continental-scale automated detection of cyanobacterial blooms in 185 Chinese lakes from 1984 to 2021 by using 30 m resolution Landsat satellite images, and the future projections of cyanobacterial blooms from 2021 to 2100 were achieved by an integrated machine learning prediction model based on Bayesian Model Averaging (BMA). We found that the high values of the maximum area proportion of cyanobacterial blooms (CBmaxA) were predominantly concentrated in eastern China, and the trajectory of geographic center moved gradually southward and eastward from 1980s to 2010s. Over the past four decades, the CBmaxA exhibited a notable upward trend, with an average annual increase of 0.11%. Climate (42.0%) and human activity (32.3%) variables are primary drivers nationwide, with a 28.6% interactive contribution. In particular, temperature exerts significant positive influences on CBmaxA at the national scale. Under future climate scenarios, the CBmaxA is projected to increase 0.34% per decade, notably in the southern China where with severe cyanobacterial blooms. This study highlights the profound impact of temperature on future cyanobacterial blooms at the national scale and the significant interaction between climate change and human activities. Our approach demonstrates strong applicability and transferability, characterized by accessible input data and robust model, which is crucial for lake ecological risks prevention under changing environments.
未来蓝藻华的预测对人类活动和气候变化共同影响下湖泊生态风险管理具有重要意义。然而,由于缺乏蓝藻华的长期数据和未来预测模型的不确定性,我们目前对大陆规模蓝藻华的了解仍然不足。利用30 m分辨率的Landsat卫星图像,开发了一种改进的基于CIE (Commission Internationale del’Eclairage)的算法,用于1984 - 2021年中国185个湖泊蓝藻华的大陆尺度自动检测,并通过基于贝叶斯模型平均(BMA)的集成机器学习预测模型实现了2021 - 2100年蓝藻华的未来预测。研究发现,20世纪80年代至2010年代,蓝藻华最大面积比例(CBmaxA)的高值区主要集中在中国东部,地理中心逐渐向南、向东移动。近40年来,CBmaxA呈明显上升趋势,年均增长0.11%。在全国范围内,气候(42.0%)和人类活动(32.3%)变量是主要驱动因素,其中交互贡献为28.6%。特别是在国家尺度上,温度对CBmaxA有显著的正向影响。在未来的气候情景下,CBmaxA预计每十年增加0.34%,特别是在蓝藻严重繁殖的中国南方。这项研究强调了温度对未来全国范围内蓝藻繁殖的深远影响,以及气候变化与人类活动之间的重要相互作用。该方法具有较强的适用性和可移植性,输入数据可获取,模型鲁棒性强,对变化环境下湖泊生态风险的防范具有重要意义。
{"title":"Future risks of cyanobacterial blooms in lakes unveiled by open access data and integrated machine learning models","authors":"Cheng Chen , Yang Liu , Zheng Sun , Qiuwen Chen , Jianyun Zhang , Jinge Ma , Mengnan He","doi":"10.1016/j.watres.2026.125428","DOIUrl":"10.1016/j.watres.2026.125428","url":null,"abstract":"<div><div>Future projections of cyanobacterial blooms is of great significance for ecological risks management in lakes under the combined influences of human activities and climate change. However, due to the lack of long-term data on cyanobacterial blooms and the uncertainty of future prediction models, our current understanding of continental-scale cyanobacterial blooms is still insufficient. This study developed an improved Commission Internationale de l´Eclairage (CIE)-based algorithm with multi-mask correction for continental-scale automated detection of cyanobacterial blooms in 185 Chinese lakes from 1984 to 2021 by using 30 m resolution Landsat satellite images, and the future projections of cyanobacterial blooms from 2021 to 2100 were achieved by an integrated machine learning prediction model based on Bayesian Model Averaging (BMA). We found that the high values of the maximum area proportion of cyanobacterial blooms (CB<sub>maxA</sub>) were predominantly concentrated in eastern China, and the trajectory of geographic center moved gradually southward and eastward from 1980s to 2010s. Over the past four decades, the CB<sub>maxA</sub> exhibited a notable upward trend, with an average annual increase of 0.11%. Climate (42.0%) and human activity (32.3%) variables are primary drivers nationwide, with a 28.6% interactive contribution. In particular, temperature exerts significant positive influences on CB<sub>maxA</sub> at the national scale. Under future climate scenarios, the CB<sub>maxA</sub> is projected to increase 0.34% per decade, notably in the southern China where with severe cyanobacterial blooms. This study highlights the profound impact of temperature on future cyanobacterial blooms at the national scale and the significant interaction between climate change and human activities. Our approach demonstrates strong applicability and transferability, characterized by accessible input data and robust model, which is crucial for lake ecological risks prevention under changing environments.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"293 ","pages":"Article 125428"},"PeriodicalIF":12.4,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146014703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.watres.2026.125431
Yi Sun , Hao Qin , Tao Liu , Shuyuan Zhao , Yi Chen
Microorganisms are key drivers of nutrient and pollutant removal in constructed wetlands (CWs). Viruses are increasingly recognized for their role in regulating microbial communities through interactions with their hosts. However, their specific roles within CW biofilms have not yet been elucidated. In this study, samples were collected from a full-scale CW employed for tertiary treatment. The viral community, prokaryotic community, and extracellular polymeric substances (EPS) composition were analyzed to elucidate the ecological roles of viruses and the dynamics of virus–prokaryote interactions. Our results revealed that viral and prokaryotic communities in CWs exhibited seasonal dynamics and were closely interconnected. The abundance ratio of lytic to lysogenic phages showed a significant negative correlation with prokaryotic α-diversity (Shannon R² = 0.35, p < 0.05; Richness R² = 0.34, p < 0.05), suggesting an association between shifts in viral infection strategies and prokaryotic community diversity. Phages infected both bacteria and archaea in CWs, and virus–host patterns in core bacterial taxa were broadly consistent with the “Kill-the-Winner” model. Moreover, phage-encoded auxiliary metabolic genes (AMGs) related to C, N, P, and S metabolism showed seasonal shifts in functional composition, indicating season-dependent variation in viral functional potential that may be associated with biogeochemical cycling in CWs. Overall, this study provides a comprehensive profile of viral communities in CWs and highlights the potential role of phages in shaping microbial community structure and function, offering new insights into virus–host interactions within biofilms in nature-based wastewater treatment technology.
{"title":"Viral community dynamics and virus–prokaryote interactions in a full-scale constructed wetland","authors":"Yi Sun , Hao Qin , Tao Liu , Shuyuan Zhao , Yi Chen","doi":"10.1016/j.watres.2026.125431","DOIUrl":"10.1016/j.watres.2026.125431","url":null,"abstract":"<div><div>Microorganisms are key drivers of nutrient and pollutant removal in constructed wetlands (CWs). Viruses are increasingly recognized for their role in regulating microbial communities through interactions with their hosts. However, their specific roles within CW biofilms have not yet been elucidated. In this study, samples were collected from a full-scale CW employed for tertiary treatment. The viral community, prokaryotic community, and extracellular polymeric substances (EPS) composition were analyzed to elucidate the ecological roles of viruses and the dynamics of virus–prokaryote interactions. Our results revealed that viral and prokaryotic communities in CWs exhibited seasonal dynamics and were closely interconnected. The abundance ratio of lytic to lysogenic phages showed a significant negative correlation with prokaryotic α-diversity (Shannon <em>R</em>² = 0.35, <em>p</em> < 0.05; Richness <em>R</em>² = 0.34, <em>p</em> < 0.05), suggesting an association between shifts in viral infection strategies and prokaryotic community diversity. Phages infected both bacteria and archaea in CWs, and virus–host patterns in core bacterial taxa were broadly consistent with the “Kill-the-Winner” model. Moreover, phage-encoded auxiliary metabolic genes (AMGs) related to C, N, P, and S metabolism showed seasonal shifts in functional composition, indicating season-dependent variation in viral functional potential that may be associated with biogeochemical cycling in CWs. Overall, this study provides a comprehensive profile of viral communities in CWs and highlights the potential role of phages in shaping microbial community structure and function, offering new insights into virus–host interactions within biofilms in nature-based wastewater treatment technology.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"293 ","pages":"Article 125431"},"PeriodicalIF":12.4,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146005604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.watres.2026.125436
Emiel Kruisdijk , Francesc Corbera-Rubio , Simon Müller , Frank Schoonenberg , Michele Laureni , Melanie Nijboer , Doris van Halem
Iron (Fe2+), manganese (Mn2+), and ammonium (NH4+) are the three most common contaminants in anaerobic groundwater and are typically removed in rapid sand filters in a series of simultaneous, uncontrolled, and interconnected redox reactions. In this study, we demonstrated separation of these oxidation processes, including reversing the order of NH4+and Mn2+oxidation, allowing Mn2+to oxidize before NH4+. To achieve this uncommon sequence, the filter was operated with low O2 concentrations (∼0.02 mmol/L, ∼0.5 mg/L) and a high pH (∼8). Under these conditions, Mn2+ oxidation is consuming all available O2, suppressing the occurrence of NH4+oxidation. In the filter with low O2 (0.08 mmol/L, ∼3 mg/L) and low pH (∼6.8), the opposite was observed, as Mn2+ oxidation was delayed under these conditions, resulting in complete O2 consumption by NH4+-oxidizing bacteria. Reactive transport modelling and parameter estimation revealed that Mn2+ oxidation is one order of magnitude faster in absence of NH4+ oxidation (1.4 × 10−2 vs 2.5 × 10−3 mmol/L), whereas NH4+ oxidation seemed to be accelerated by simultaneous Mn2+ oxidation (6.8 × 10−3 vs 2.9 × 10−2 s−1). This interconnection between Mn2+ and NH4+ oxidation was further emphasized by the observation of Mn2+ release in the presence of NO2−. In conclusion, this study has shown that a shift from conventional aerated groundwater treatment to sequential oxidation in separate filters offers (i) a more controllable system, (ii) the potential to optimize the rates of each oxidation process separately, which would ultimately result in higher flows and less backwashing.
{"title":"pH-based control of NH4+ and Mn2+ oxidation sequence in low-oxygen groundwater filters","authors":"Emiel Kruisdijk , Francesc Corbera-Rubio , Simon Müller , Frank Schoonenberg , Michele Laureni , Melanie Nijboer , Doris van Halem","doi":"10.1016/j.watres.2026.125436","DOIUrl":"10.1016/j.watres.2026.125436","url":null,"abstract":"<div><div>Iron (Fe<sup>2+</sup>), manganese (Mn<sup>2+</sup>), and ammonium (NH<sub>4</sub><sup>+</sup>) are the three most common contaminants in anaerobic groundwater and are typically removed in rapid sand filters in a series of simultaneous, uncontrolled, and interconnected redox reactions. In this study, we demonstrated separation of these oxidation processes, including reversing the order of NH<sub>4</sub><sup>+</sup>and Mn<sup>2+</sup>oxidation, allowing Mn<sup>2+</sup>to oxidize before NH<sub>4</sub><sup>+</sup>. To achieve this uncommon sequence, the filter was operated with low O<sub>2</sub> concentrations (∼0.02 mmol/L, ∼0.5 mg/L) and a high pH (∼8). Under these conditions, Mn<sup>2+</sup> oxidation is consuming all available O<sub>2</sub>, suppressing the occurrence of NH<sub>4</sub><sup>+</sup>oxidation. In the filter with low O<sub>2</sub> (0.08 mmol/L, ∼3 mg/L) and low pH (∼6.8), the opposite was observed, as Mn<sup>2+</sup> oxidation was delayed under these conditions, resulting in complete O<sub>2</sub> consumption by NH<sub>4</sub><sup>+</sup>-oxidizing bacteria. Reactive transport modelling and parameter estimation revealed that Mn<sup>2+</sup> oxidation is one order of magnitude faster in absence of NH<sub>4</sub><sup>+</sup> oxidation (1.4 × 10<sup>−2</sup> vs 2.5 × 10<sup>−3</sup> mmol/L), whereas NH<sub>4</sub><sup>+</sup> oxidation seemed to be accelerated by simultaneous Mn<sup>2+</sup> oxidation (6.8 × 10<sup>−3</sup> vs 2.9 × 10<sup>−2</sup> s<sup>−1</sup>). This interconnection between Mn<sup>2+</sup> and NH<sub>4</sub><sup>+</sup> oxidation was further emphasized by the observation of Mn<sup>2+</sup> release in the presence of NO<sub>2</sub><sup>−</sup>. In conclusion, this study has shown that a shift from conventional aerated groundwater treatment to sequential oxidation in separate filters offers (i) a more controllable system, (ii) the potential to optimize the rates of each oxidation process separately, which would ultimately result in higher flows and less backwashing.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"293 ","pages":"Article 125436"},"PeriodicalIF":12.4,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146014700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.watres.2026.125433
Jian Wang , Guangtao Fu , Dragan Savic
Water distribution networks (WDNs), a critical part of urban infrastructure, normally require numerous model simulations for effective planning and management. However, traditional WDN modelling requires complex workflows and specialized expertise. EPANET is the most widely adopted modelling tool for WDN hydraulics and water quality simulations, yet its operational complexity restricts accessibility and slows timely decision-making. Recent advances in large language models (LLMs) have led to the development of agentic artificial intelligence systems that autonomously coordinate tasks and control complex engineering simulations through natural language prompts. Here we introduce EPANET-Agentic, a multi-agent system that integrates advanced workflow reasoning with the EPANET simulator and incorporates human-in-the-loop oversight for critical interventions. The new platform adopts an orchestrator-centred, tool-driven architecture that nests three specialised agents (TaskExecutor, CodeRunner, and DataAnalyzer) as function-call tools. This design enables autonomous task decomposition, precise tool invocation, and transparent workflow management. The abilities of EPANET-Agentic are evaluated on three benchmark networks (i.e., L-Town, C-Town, and Net3) across four categories of tasks: System Characteristics, System Dynamics, System Operation, and Scenario Simulation. The results demonstrate that EPANET-Agentic achieved a 100% success rate and tool invocation accuracy with no human interventions. Moreover, the multimodal DataAnalyzer agent provided valid interpretations of simulation results, while the nested tool design ensured robustness and the architecture exhibited strong scalability across diverse hydraulic analysis tasks. These findings confirm that EPANET-Agentic enables natural language-controlled WDN simulation and analysis with engineering-grade reliability, while still adhering to a human-in-the-loop approach required for safety-critical systems. With its modular architecture and strong adaptability, EPANET-Agentic marks a step change from conventional WDN modelling approaches, positioning itself as a next-generation platform for complex planning and management challenges.
{"title":"EPANET-Agentic: A multi-agent system for natural language-controlled simulations of water distribution networks","authors":"Jian Wang , Guangtao Fu , Dragan Savic","doi":"10.1016/j.watres.2026.125433","DOIUrl":"10.1016/j.watres.2026.125433","url":null,"abstract":"<div><div>Water distribution networks (WDNs), a critical part of urban infrastructure, normally require numerous model simulations for effective planning and management. However, traditional WDN modelling requires complex workflows and specialized expertise. EPANET is the most widely adopted modelling tool for WDN hydraulics and water quality simulations, yet its operational complexity restricts accessibility and slows timely decision-making. Recent advances in large language models (LLMs) have led to the development of agentic artificial intelligence systems that autonomously coordinate tasks and control complex engineering simulations through natural language prompts. Here we introduce EPANET-Agentic, a multi-agent system that integrates advanced workflow reasoning with the EPANET simulator and incorporates human-in-the-loop oversight for critical interventions. The new platform adopts an orchestrator-centred, tool-driven architecture that nests three specialised agents (TaskExecutor, CodeRunner, and DataAnalyzer) as function-call tools. This design enables autonomous task decomposition, precise tool invocation, and transparent workflow management. The abilities of EPANET-Agentic are evaluated on three benchmark networks (i.e., L-Town, C-Town, and Net3) across four categories of tasks: System Characteristics, System Dynamics, System Operation, and Scenario Simulation. The results demonstrate that EPANET-Agentic achieved a 100% success rate and tool invocation accuracy with no human interventions. Moreover, the multimodal DataAnalyzer agent provided valid interpretations of simulation results, while the nested tool design ensured robustness and the architecture exhibited strong scalability across diverse hydraulic analysis tasks. These findings confirm that EPANET-Agentic enables natural language-controlled WDN simulation and analysis with engineering-grade reliability, while still adhering to a human-in-the-loop approach required for safety-critical systems. With its modular architecture and strong adaptability, EPANET-Agentic marks a step change from conventional WDN modelling approaches, positioning itself as a next-generation platform for complex planning and management challenges.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"293 ","pages":"Article 125433"},"PeriodicalIF":12.4,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146014698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.watres.2026.125429
Song Yaran, Ling Chen, Cheng Ximeng, Yang Yujia, Jian Meili, Zhu Qiuchen, Zhang Qingrui
Hydrous ferric oxide (HFO) based hybrid adsorbents are extensively used for heavy metal removal due to their high sorption efficiency and operational durability. However, the complexity of real electroplating wastewater, with high loads of organics, salts, and acid, critically challenges their stability, resulting in short service life. Here, we developed a polydopamine (PDA)-confined strategy to enhance the stability of HFO, using a commercial HFO–polystyrene nanocomposite (PS-Fe) as model. We unveil a collaborative “Proton-Sponge and Size-Exclusion” underpinning the enhanced stability. The catechol-rich PDA matrix acts as an effective proton buffer to regulate the local chemical environment, while its crosslinked network selectively excludes macromolecular organic ligands, thereby protecting the embedded HFO nanoparticles from complexation and dissolution. Under aggressive conditions-including extreme pH, high salinity, mixed organic acids, elevated temperature, and prolonged operation-the PDA-confined PSP-Fe demonstrated 2 to 7-fold reduction in Fe leaching compared to bulk HFO and the unmodified PS-Fe. The improved structural integrity further conferred exceptional selectivity in multicomponent competing systems, achieving a distribution coefficient (Kd) of 10271 mL/g, 5 to 41 times higher than reference materials. Multi-site field-scale tests validated its engineering applicability, yielding the treatment capacity of 3600–4300 L water/kg with effluent Pb(II) level below 10 μg/L. Our work provides a generalized materials strategy to enhance the durability and efficiency of HFO-based adsorbents, advancing sustainable heavy metal removal.
基于氢氧化铁(HFO)的混合吸附剂由于其高吸附效率和耐用性而被广泛用于重金属去除。然而,实际电镀废水的复杂性,具有高负荷的有机物,盐和酸,严重挑战了它们的稳定性,导致使用寿命短。本研究以商用HFO -聚苯乙烯纳米复合材料(PS-Fe)为模型,开发了一种聚多巴胺(PDA)约束策略来增强HFO的稳定性。我们推出了一种协作的“质子海绵和尺寸排除”,以增强稳定性。富含儿茶酚的PDA基质作为有效的质子缓冲剂调节局部化学环境,而其交联网络选择性地排除大分子有机配体,从而保护嵌入的HFO纳米颗粒不被络合和溶解。在恶劣的条件下,包括极端pH值、高盐度、混合有机酸、高温和长时间的操作,与散装HFO和未改性的PS-Fe相比,pda限制的PSP-Fe的铁浸出率降低了2至7倍。改进的结构完整性进一步赋予了在多组分竞争体系中出色的选择性,实现了10271 mL/g的分配系数(Kd),比标准物质高5到41倍。多场现场试验验证了其工程适用性,出水Pb(II)水平低于10 μg/L,处理能力为3600 ~ 4300 L /kg。我们的工作为提高hfo吸附剂的耐用性和效率提供了一种通用的材料策略,促进了重金属的可持续去除。
{"title":"Nanoconfinement engineering enhances HFO stability: Dual proton-sponge and size-exclusion strategy for robust heavy-metal sequestration in real electroplating effluents","authors":"Song Yaran, Ling Chen, Cheng Ximeng, Yang Yujia, Jian Meili, Zhu Qiuchen, Zhang Qingrui","doi":"10.1016/j.watres.2026.125429","DOIUrl":"10.1016/j.watres.2026.125429","url":null,"abstract":"<div><div>Hydrous ferric oxide (HFO) based hybrid adsorbents are extensively used for heavy metal removal due to their high sorption efficiency and operational durability. However, the complexity of real electroplating wastewater, with high loads of organics, salts, and acid, critically challenges their stability, resulting in short service life. Here, we developed a polydopamine (PDA)-confined strategy to enhance the stability of HFO, using a commercial HFO–polystyrene nanocomposite (PS-Fe) as model. We unveil a collaborative “Proton-Sponge and Size-Exclusion” underpinning the enhanced stability. The catechol-rich PDA matrix acts as an effective proton buffer to regulate the local chemical environment, while its crosslinked network selectively excludes macromolecular organic ligands, thereby protecting the embedded HFO nanoparticles from complexation and dissolution. Under aggressive conditions-including extreme pH, high salinity, mixed organic acids, elevated temperature, and prolonged operation-the PDA-confined PSP-Fe demonstrated 2 to 7-fold reduction in Fe leaching compared to bulk HFO and the unmodified PS-Fe. The improved structural integrity further conferred exceptional selectivity in multicomponent competing systems, achieving a distribution coefficient (K<sub>d</sub>) of 10271 mL/g, 5 to 41 times higher than reference materials. Multi-site field-scale tests validated its engineering applicability, yielding the treatment capacity of 3600–4300 L water/kg with effluent Pb(II) level below 10 μg/L. Our work provides a generalized materials strategy to enhance the durability and efficiency of HFO-based adsorbents, advancing sustainable heavy metal removal.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"293 ","pages":"Article 125429"},"PeriodicalIF":12.4,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146014707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.watres.2026.125432
Zi-Tong Li , Zecong Ding , Yingjie Chen , Kai Cui , Li Wang , Hai-Yan Zhang , Qian Jiang , Li-Qian Lin , Jian-Liang Zhao
Novel plastic additives (NPAs), such as antioxidants and vulcanization accelerators, are frequently used in electroplated plastic products and electroplating solutions. However, their occurrence, migration pathways during the wastewater treatment process in electroplating parks and their environmental impact after discharge remain poorly understood. Here, we present the first comprehensive multi-matrix assessment of 35 NPAs, including p-phenylenediamines and their quinone derivatives, benzothiazoles and their derivatives, guanidine derivatives, and others, across wastewater, sludge, surface water, groundwater, and sediments from four electroplating parks in South China. Caprolactam and 1,3-Diphenylurea (DPU) dominated in influent (up to 5575 ng/L) and effluent (up to 1027 ng/L), whereas 6PPD (up to 2969 ng/g) prevailed in sludge. Treatment removal efficiencies ranged from 23.5 % to 95.2 %, with the membrane bioreactor achieving the highest removal (84.6 %), while hydrolysis acidification units promoted the formation of NPAs. The mass loadings of NPAs in sludge exceeded the influent-effluent differentials, suggesting that substantial NPAs were retained in the sludge. Concentrations of total NPAs in surface waters were highest at the On-site locations (up to 4358 ng/L), while groundwater beneath the treatment plants reached levels as high as 6431 ng/L. Multivariate statistical analysis identified electroplating wastewater as a primary source of pollution in the surrounding waters, with hydrophilic compounds migrating via surface–groundwater exchange, while sediments served as the ultimate sink for hydrophobic NPAs. Ecological risk assessment revealed medium-to-high risks, specifically identifying 2,5-bis(o-tolylamino)cyclohexa-2,5-diene-1,4‑dione (DTPD-Q), DPU, and 1,3-Diphenylguanidine (DPG) as high-priority pollutants in the aquatic environment surrounding electroplating parks. Our study illustrates the extensive persistence and mobility of NPAs across both engineered and environmental systems, emphasizing the necessity for upgraded treatment and integrated tracking of their migration from industrial sources.
{"title":"Electroplating parks as hidden sources of novel plastic additives: Occurrence, migration pathways, and ecological risks","authors":"Zi-Tong Li , Zecong Ding , Yingjie Chen , Kai Cui , Li Wang , Hai-Yan Zhang , Qian Jiang , Li-Qian Lin , Jian-Liang Zhao","doi":"10.1016/j.watres.2026.125432","DOIUrl":"10.1016/j.watres.2026.125432","url":null,"abstract":"<div><div>Novel plastic additives (NPAs), such as antioxidants and vulcanization accelerators, are frequently used in electroplated plastic products and electroplating solutions. However, their occurrence, migration pathways during the wastewater treatment process in electroplating parks and their environmental impact after discharge remain poorly understood. Here, we present the first comprehensive multi-matrix assessment of 35 NPAs, including <em>p</em>-phenylenediamines and their quinone derivatives, benzothiazoles and their derivatives, guanidine derivatives, and others, across wastewater, sludge, surface water, groundwater, and sediments from four electroplating parks in South China. Caprolactam and 1,3-Diphenylurea (DPU) dominated in influent (up to 5575 ng/L) and effluent (up to 1027 ng/L), whereas 6PPD (up to 2969 ng/g) prevailed in sludge. Treatment removal efficiencies ranged from 23.5 % to 95.2 %, with the membrane bioreactor achieving the highest removal (84.6 %), while hydrolysis acidification units promoted the formation of NPAs. The mass loadings of NPAs in sludge exceeded the influent-effluent differentials, suggesting that substantial NPAs were retained in the sludge. Concentrations of total NPAs in surface waters were highest at the On-site locations (up to 4358 ng/L), while groundwater beneath the treatment plants reached levels as high as 6431 ng/L. Multivariate statistical analysis identified electroplating wastewater as a primary source of pollution in the surrounding waters, with hydrophilic compounds migrating via surface–groundwater exchange, while sediments served as the ultimate sink for hydrophobic NPAs. Ecological risk assessment revealed medium-to-high risks, specifically identifying 2,5-bis(o-tolylamino)cyclohexa-2,5-diene-1,4‑dione (DTPD-Q), DPU, and 1,3-Diphenylguanidine (DPG) as high-priority pollutants in the aquatic environment surrounding electroplating parks. Our study illustrates the extensive persistence and mobility of NPAs across both engineered and environmental systems, emphasizing the necessity for upgraded treatment and integrated tracking of their migration from industrial sources.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"293 ","pages":"Article 125432"},"PeriodicalIF":12.4,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146005950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-19DOI: 10.1016/j.watres.2026.125420
Di Wang , Guilin Han , Yuchun Wang , Shunrong Ma
Large reservoirs, such as the Three Gorges Reservoir (TGR), act as distinct biogeochemical reactors within the global riverine system. However, their dual role as recipients of pollution and modifiers of contaminant fate remains incompletely understood. Dissolved rare earth elements (REEs) in rivers serve as sensitive tracers of continental weathering and anthropogenic perturbations, making them valuable for deciphering such complex processes. This study aims to characterize the spatial distribution of dissolved REEs, quantify anthropogenic inputs versus natural weathering sources, and elucidate the geochemical fractionation mechanisms driven by reservoir operations in the TGR. The observed riverine total REE concentrations ranged from 6.8 to 102.9 ng/L (median: 14.6 ng/L), and fractionation parameters revealed compositional signatures closely linked to rock weathering. Notably, widespread positive gadolinium (Gd) anomalies (median δGd: 2.6) were observed. Unlike previous investigations from the initial impoundment period (2003–2006) which reported natural background levels, this study documents the emergence of a distinct anthropogenic Gd signal derived from sources such as medical wastewater. To rigorously distinguish these inputs, Positive Matrix Factorization modeling was applied base on the dissolved REE dataset. The model was constrained by observation-based uncertainties to optimize source apportionment. The model successfully quantified mixed anthropogenic inputs, accounting for 32.4 % of the total dissolved REEs. In contrast, a comparison with historical data suggests a significant long-term removal effect driven by reservoir operations, since the current dissolved REE concentrations was one order of magnitude lower than the historical baselines. This enhanced scavenging is further supported by an increase in Y/Ho molar ratios (from ∼58.0 to ∼76.0). These findings reveal the decoupling of REE geochemical behaviors: reservoir operations promote the persistence of conservative anthropogenic geochemical signatures (e.g., Gd anomalies), while simultaneously enhancing the removal of particulate-reactive REEs via sedimentation. This work highlights the utility of REE anomalies as specific early-warning indicators, and suggests using the δGd thresholds as an indicator for assessing pollutant loads from wastewater in large reservoir systems.
{"title":"Anthropogenic gadolinium anomalies and reservoir-driven removal of dissolved rare earth elements in the world's largest hydropower project","authors":"Di Wang , Guilin Han , Yuchun Wang , Shunrong Ma","doi":"10.1016/j.watres.2026.125420","DOIUrl":"10.1016/j.watres.2026.125420","url":null,"abstract":"<div><div>Large reservoirs, such as the Three Gorges Reservoir (TGR), act as distinct biogeochemical reactors within the global riverine system. However, their dual role as recipients of pollution and modifiers of contaminant fate remains incompletely understood. Dissolved rare earth elements (REEs) in rivers serve as sensitive tracers of continental weathering and anthropogenic perturbations, making them valuable for deciphering such complex processes. This study aims to characterize the spatial distribution of dissolved REEs, quantify anthropogenic inputs versus natural weathering sources, and elucidate the geochemical fractionation mechanisms driven by reservoir operations in the TGR. The observed riverine total REE concentrations ranged from 6.8 to 102.9 ng/L (median: 14.6 ng/L), and fractionation parameters revealed compositional signatures closely linked to rock weathering. Notably, widespread positive gadolinium (Gd) anomalies (median δGd: 2.6) were observed. Unlike previous investigations from the initial impoundment period (2003–2006) which reported natural background levels, this study documents the emergence of a distinct anthropogenic Gd signal derived from sources such as medical wastewater. To rigorously distinguish these inputs, Positive Matrix Factorization modeling was applied base on the dissolved REE dataset. The model was constrained by observation-based uncertainties to optimize source apportionment. The model successfully quantified mixed anthropogenic inputs, accounting for 32.4 % of the total dissolved REEs. In contrast, a comparison with historical data suggests a significant long-term removal effect driven by reservoir operations, since the current dissolved REE concentrations was one order of magnitude lower than the historical baselines. This enhanced scavenging is further supported by an increase in Y/Ho molar ratios (from ∼58.0 to ∼76.0). These findings reveal the decoupling of REE geochemical behaviors: reservoir operations promote the persistence of conservative anthropogenic geochemical signatures (e.g., Gd anomalies), while simultaneously enhancing the removal of particulate-reactive REEs via sedimentation. This work highlights the utility of REE anomalies as specific early-warning indicators, and suggests using the δGd thresholds as an indicator for assessing pollutant loads from wastewater in large reservoir systems.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"293 ","pages":"Article 125420"},"PeriodicalIF":12.4,"publicationDate":"2026-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146001379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-19DOI: 10.1016/j.watres.2026.125425
Xinyuan He , Yi Lu , Yuxiang Zhou , Xuyu Yu , Jianlei Zhu , Ke Chen , Zongying Ding , Shiye Sun , Shaoan Cheng
Real-time monitoring of biochemical oxygen demand (BOD) is crucial for optimizing wastewater treatment processes and evaluating water environmental quality. This study developed an integrated online BOD monitoring system based on bioelectrochemical system (BES) technology. Through automated process design and parameter optimization, the system achieved a detection range of 12.8–172.8 mg l-1 BOD (R²=0.995). Long-term stability assessment revealed that despite biosensor performance degradation during continuous measurements, the system maintained high accuracy (relative error <1.1%) through a baseline recalibration strategy implemented every 100 measurements. Field validation for the hydrolysis acidification tank (HAT) effluent demonstrated the capability of the system to monitor dynamic BOD variations and respond rapidly to process manipulation such as carbon source addition. By establishing a correction model specifically for the HAT effluent samples, the system achieved a relative measurement error of 6.73%. The results demonstrate the robustness of the developed system in long-term real-time BOD monitoring of HAT effluent, which may provide data support for downstream process regulation.
{"title":"Development and long-term technical validation of an automated bioelectrochemical system for online BOD monitoring of wastewater hydrolysis acidification effluent","authors":"Xinyuan He , Yi Lu , Yuxiang Zhou , Xuyu Yu , Jianlei Zhu , Ke Chen , Zongying Ding , Shiye Sun , Shaoan Cheng","doi":"10.1016/j.watres.2026.125425","DOIUrl":"10.1016/j.watres.2026.125425","url":null,"abstract":"<div><div>Real-time monitoring of biochemical oxygen demand (BOD) is crucial for optimizing wastewater treatment processes and evaluating water environmental quality. This study developed an integrated online BOD monitoring system based on bioelectrochemical system (BES) technology. Through automated process design and parameter optimization, the system achieved a detection range of 12.8–172.8 mg <span>l</span><sup>-1</sup> BOD (R²=0.995). Long-term stability assessment revealed that despite biosensor performance degradation during continuous measurements, the system maintained high accuracy (relative error <1.1%) through a baseline recalibration strategy implemented every 100 measurements. Field validation for the hydrolysis acidification tank (HAT) effluent demonstrated the capability of the system to monitor dynamic BOD variations and respond rapidly to process manipulation such as carbon source addition. By establishing a correction model specifically for the HAT effluent samples, the system achieved a relative measurement error of 6.73%. The results demonstrate the robustness of the developed system in long-term real-time BOD monitoring of HAT effluent, which may provide data support for downstream process regulation.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"293 ","pages":"Article 125425"},"PeriodicalIF":12.4,"publicationDate":"2026-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146001377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-19DOI: 10.1016/j.watres.2026.125421
Ze-Xian Low, Stephen Gray, S. Ranil Wickramasinghe, Xing Yang, Pascal Saikaly, Ana Deletic
{"title":"Membrane Technology for Resource Recovery","authors":"Ze-Xian Low, Stephen Gray, S. Ranil Wickramasinghe, Xing Yang, Pascal Saikaly, Ana Deletic","doi":"10.1016/j.watres.2026.125421","DOIUrl":"https://doi.org/10.1016/j.watres.2026.125421","url":null,"abstract":"","PeriodicalId":443,"journal":{"name":"Water Research","volume":"273 1","pages":""},"PeriodicalIF":12.8,"publicationDate":"2026-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146000992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}