Journal of contaminant hydrology最新文献

{"title":"Application of spectral induced polarization technique in monitoring zinc removal by activated carbon as a permeable reactive barrier material","authors":"Sheng Zhou ,&nbsp;Yi-Xin Yang ,&nbsp;Jing-Jing Cao ,&nbsp;Long-Long Meng ,&nbsp;Lin-Han Wang ,&nbsp;Chi Zhang ,&nbsp;Bate Bate","doi":"10.1016/j.jconhyd.2025.104661","DOIUrl":"10.1016/j.jconhyd.2025.104661","url":null,"abstract":"<div><div>Zinc accumulates in groundwater from mining operation and discarded batteries and poses a threat to environmental safety and human health. Activated carbon (AC), is an affordable media of permeable reactive barrier (PRB) for the in-situ zinc remediation. In this study, column breakthrough tests with spectral induced polarization technique monitoring, coupled with microscopic analyses, were utilized to investigate the zinc retention behaviors in activated carbon PRB. Chemical analysis indicated that Zn²⁺ retention on AC surface was primarily governed by cation exchange, electrostatic adsorption and precipitation. The quantity of Zn retention was well characterized by the real-time normalized chargeability derived from SIP signals. The Zn²⁺ migration simulation and characteristic polarizable units size revealed that the 0.01 μm pore throat channels impeded Zn²⁺ migration into internal pores at low Zn²⁺ inflow concentration due to restriction of overlapping electric double layer, which resulted in a reduction of effective adsorption area. This transport-limiting effect is alleviated at higher Zn²⁺ inflow concentrations due to EDL compression. Above results suggest the feasibility of the SIP technique in real-time monitoring of Zn remediation processes in a permeable reactive barrier set up.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"274 ","pages":"Article 104661"},"PeriodicalIF":3.5,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144518114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Toward explicit learning frameworks for predicting the solubility of CO2 – N2 gas mixtures in brine: Implication for impure CO2 storage in saline aquifers","authors":"Saad Alatefi ,&nbsp;Menad Nait Amar ,&nbsp;Okorie Ekwe Agwu ,&nbsp;Ahmad Alkouh","doi":"10.1016/j.jconhyd.2025.104660","DOIUrl":"10.1016/j.jconhyd.2025.104660","url":null,"abstract":"<div><div>Carbon capture and storage (CCS) is a crucial technology for reducing industrial CO₂ emissions and mitigating climate change. However, its large-scale deployment faces significant financial challenges, with CO₂ capture and compression accounting for the great part of total costs. To reduce these expenses, the injection of impure CO₂ streams, particularly CO₂–N₂ mixtures, into saline aquifers is among the viable alternatives to minimizing the need for costly separation processes. The effectiveness of this approach depends on consistently estimating CO₂–N₂ solubility in brine under varying scenarios, as solubility directly influences storage efficiency, injection feasibility, and long-term formation stability. Experimental methods, while precise, are expensive and time-intensive, highlighting the need for efficient predictive models. In this study, robust and interpretable white-box correlations are introduced using the multigene genetic programming (MGGP) approach to estimate CO₂–N₂ gas mixtures solubility in brine. The correlations were trained and validated on a representative experimental database, ensuring reliable predictions across diverse pressure, temperature, and salinity conditions. The MGGP-based correlations achieved high overall R² of 0.9967 for CO₂ and 0.9914 for N₂, with small RMSE values of 0.000363 and 0.000052, respectively. These correlations not only ensure accuracy and physical consistency, confirmed through detailed trend analyses, but also significantly outperform previous approaches reported in the literature. Furthermore, SHAP technique was employed to enhance model interpretability and deepen understanding of input parameter contributions. These correlations offer a powerful, practical tool for real-world CCS applications, including techno-economic assessments and the design of injection strategies, especially when considering impure gas streams.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"274 ","pages":"Article 104660"},"PeriodicalIF":3.5,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Sorption-desorption processes contributing to natural attenuation of trichloroethene in porous media","authors":"Katelyn A. Anderson ,&nbsp;Uriel Garza-Rubalcava ,&nbsp;Allison Stein ,&nbsp;Mark A. Widdowson ,&nbsp;Eric J. Suchomel ,&nbsp;Natalie L. Cápiro ,&nbsp;Kurt D. Pennell","doi":"10.1016/j.jconhyd.2025.104658","DOIUrl":"10.1016/j.jconhyd.2025.104658","url":null,"abstract":"<div><div>Monitored natural attenuation (MNA), which relies on natural processes to reduce contaminant concentrations over time, is widely used to manage dilute chlorinated solvent groundwater plumes. In heterogeneous aquifers, the accumulation and subsequent release of chlorinated solvents can strongly influence the long-term effectiveness of MNA. This research investigated rate-limited sorption-desorption processes influencing trichloroethene (TCE) release from lower-permeability media. Batch reactor studies were conducted with four natural soils to establish equilibrium linear distribution coefficients (<em>K</em>_D), which ranged from 0.4 to 1.0 mL/g. Column transport studies were then completed using the same soils at two flow rates, with periods of flow interruption, to assess rate-limited desorption. A numerical simulator that incorporates a “two-site” sorption model was used to fit the effluent concentration data and obtain parameters for fraction of sorption sites at instantaneous equilibrium (<em>f</em>) and the rate of sorption for time-dependent sites (<em>k</em>), which ranged from 0.2 to 0.6 and 0.3 day⁻¹ to 3 day⁻¹, respectively. Subsequent model simulations were used to illustrate the importance of these sorption parameters on the extended release of TCE from low permeability porous media. These finding demonstrate that in addition to back diffusion, rate-limited sorption-desorption processes should be considered when evaluating MNA as long-term remedies for chlorinated solvent plumes.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"274 ","pages":"Article 104658"},"PeriodicalIF":3.5,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144471388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Metal pollution in surface sediments of the Vembanad wetland: Seasonal variation, source apportionment, and human health risk assessment","authors":"Anjana K.R,&nbsp;Vishnuja Soman,&nbsp;Anju Suresh,&nbsp;Habeeb Rahman K","doi":"10.1016/j.jconhyd.2025.104656","DOIUrl":"10.1016/j.jconhyd.2025.104656","url":null,"abstract":"<div><div>This study examines the origins, distribution, and health impact of potentially toxic elements (PTEs) found in the surface sediments of Vembanad Wetland, a Ramsar site on India's southwest coast. Sediment from 14 sampling locations was seasonally analysed for Fe, Mn, Cu, Ni, Co, Zn, Cr, Pb and Cd. The average concentration of PTEs (mg/kg) follows the order: Fe (35,668.07 ± 20,082.98) &gt; Mn (307.5 ± 36.71) &gt; Zn (155.96 ± 99.45) &gt; Cr (119.94 ± 79) &gt; Ni (92.66 ± 32.69) &gt; Cu (42.29 ± 17.26) &gt; Pb (21.67 ± 11.65) &gt; Co (20.64 ± 14.32) &gt; Cd (2.21 ± 0.78). Higher average contamination factor (CF), enrichment factor (EF) and geoaccumulation index were observed for Cd (CF = 4.17, EF = 7.73, Igeo = 2.18) and Zn (CF = 4.85, EF = 2.44, Igeo = 0.38), indicating substantial anthropogenic enrichment. The average values of pollution indices such as PLI (1.49), TRI (11.69), mCd (15.1), and RI (251.69) indicate moderate to significant pollution. Average modified hazard quotient (mHQ) values revealed that Ni (3.19), Cr (2.76), Cd (1.99), and Zn (1.64) posed notable ecological risks. A potential health concern from prolonged exposure was indicated by the increased average total carcinogenic risk (TCR) values for Ni (9.24E-2), Cr (6.57E-2), and Cd (3.62E-2) in children. Multivariate analyses (PCA, PCC, HCA) suggested common contamination sources, with PCA-MLR confirming industrial discharge and agricultural runoff as dominant contributors. This study uniquely integrates seasonal variability, advanced pollution indices, and health risk evaluation, highlighting the urgent need for targeted management strategies in these sensitive aquatic systems.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"274 ","pages":"Article 104656"},"PeriodicalIF":3.5,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144471387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Research on the potential of the deep learning-based “decomposition-optimization-reconstruction” method in runoff prediction for typical climate- and human-regulated basins in northern China","authors":"Zixiang Guo ,&nbsp;Baolin Xue ,&nbsp;Junping Wang ,&nbsp;Xuan Zhou ,&nbsp;Yinglan A ,&nbsp;Yuntao Wang ,&nbsp;Jin Wu","doi":"10.1016/j.jconhyd.2025.104655","DOIUrl":"10.1016/j.jconhyd.2025.104655","url":null,"abstract":"<div><div>River runoff may be affected mainly by the natural climate or human activities, and runoff series present complex characteristics, such as non-stationarity, which makes accurate prediction of runoff challenging. To address the problem that the prediction accuracy of the traditional deep learning methods is affected by the non-stationarity of runoff, which is based on the idea of “decomposition - optimization – reconstruction”, this paper constructs a combination model that introduces variational mode decomposition (VMD) and the whale optimization algorithm (WOA) to optimize a bidirectional long short-term memory neural network (BiLSTM) (VMD-WOA-BiLSTM). The combination model is applied to runoff prediction in typical climate- and human-regulated watersheds in northern China, specifically in the semi-arid regions of the Hailar River Basin and the Dahei River Basin. The results show that the “decomposition-optimization-reconstruction” model significantly improves the prediction accuracy. The model excels in upstream runoff prediction because there are fewer human activities in those areas compared to the downstream areas. When applied to rivers, it more accurately forecasts climate-driven runoff changes and performs better for rivers with relatively large total runoff, which may be because they are less impacted by extreme precipitation events compared with rivers with small total runoff. The model's prediction performance varies across different seasons, which may be related to the seasonal characteristics of runoff and the model's inherent predictive capabilities. The combined model achieves excellent runoff prediction results across various river segments and basins, demonstrating its wide applicability for climate- and human-regulated basins in northern China.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"274 ","pages":"Article 104655"},"PeriodicalIF":3.5,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144365445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Metal treatment in stormwater bioretention systems with high hydraulic conductivity – Designed for more efficient runoff volume capture and cold climates","authors":"Robert Furén ,&nbsp;Katharina Lange ,&nbsp;Ali Beryani ,&nbsp;Maria Viklander ,&nbsp;Godecke-Tobias Blecken","doi":"10.1016/j.jconhyd.2025.104654","DOIUrl":"10.1016/j.jconhyd.2025.104654","url":null,"abstract":"<div><div>Bioretention systems are used to treat stormwater. Using coarser filter media than commonly recommended with high saturated hydraulic conductivities may increase annual runoff volume capture, facilitate smaller filters, less overflow and adaptation to cold winters. However, this may affect water quality treatment negatively. Therefore, we investigated total and dissolved metal treatment at three full scale bioretention systems with a coarse filter material and saturated hydraulic conductivities &gt;1500 mm/h in Malmö/Sweden. One bioretention system was designed with a coarse sand-based filter medium, another with coarse sand-based filter medium and a submerged zone and the third with a 50:50 mixture of coarse sand and pumice as filter medium. The study included 19 rain events, partly during winter season when road salt was applied. The results suggest that also filter media with high hydraulic conductivity can be an effective option when metal treatment is targeted. The two systems with coarse sand filter media treated total metals effectively with median removals &gt;80 % for Cu, Pb and Zn and median removals &gt;35 % for Ni and Cr. Dissolved metal treatment was variable reaching from effective treatment for dissolved Cu, Pb and Zn with median removals &gt;60 % to overall leaching of dissolved Cd, Ni and Cr. Applying a submerged zone did not showed benefits for total or dissolved metal removal. Further, treatment of total and partly dissolved metals was significantly impaired due to pumice addition of the filter media, discouraging pumice as a filter media amendment. Coarser filter materials could be recommended for sites with space limitations or when frozen ground is expected in winter. Further, they can generally reduce clogging risks and untreated overflows.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"274 ","pages":"Article 104654"},"PeriodicalIF":3.5,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144322191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Influencing factors for the spatial distribution and deposition history of microplastics in the sediments of Chaohu Lake, China","authors":"Zihui Zhao ,&nbsp;Jianuo He ,&nbsp;Changyu Ma ,&nbsp;Yaguang Nie ,&nbsp;Liqiang Xu ,&nbsp;Zongbin Zhang ,&nbsp;Xiaodong Liu ,&nbsp;Lijun Wu","doi":"10.1016/j.jconhyd.2025.104653","DOIUrl":"10.1016/j.jconhyd.2025.104653","url":null,"abstract":"<div><div>Microplastic (MP) pollution resulting from industrialization and urbanization is obtaining increasing attention. Focusing on the pollution status in Chaohu Lake, the spatial distribution, concentration, particle size, and polymer composition of MPs were measured. The concentration of MPs in the Chaohu Lake surface sediments (<em>n</em> = 26) ranged from 6.34 to 81.98 items/g, and the most abundant polymers in the samples were chlorinated polyisoprene (CPI), polyvinylchloride (PVC), and polyethyl terephthalate (PET). The spatial distribution of MPs did not correlate well with indices representing the depositional environment but corresponded well to the anthropogenic factors. Multiple risk assessment tools were employed to evaluate the surface sediments, and high-risk levels were concluded. Simultaneously, an analysis on a profile encoded CHX from Chaohu Lake was carried out. A total of 27 polymer types were identified, with PET as the dominant type, accounting for more than 85.4 % of the total. The concentration of MPs in the profile ranged from 13.51 to 6089.22 items/g, which was much higher than that in the surface sediments. The size of MPs was mainly concentrated in the range of 20–50 μm, accounting for 56.3 % in the surface sediments and 77.4 % in the profile. MPs such as chlorinated polyethylene (CPE), PET, and fluororubber (FKM) were detected at depths predating their initial industrial production or widespread application, suggesting potential downward migration. From the perspective of temporal variation, MPs in the CHX profile increased from 13.51 items/g (9 cm, 1943) to 2586.06 items/g (8 cm, 1951), which is consistent with the large-scale production of plastics in the 1950s. The current study provided a dataset for the spatio-temporal distribution of MPs and enhanced our understanding of their environmental behavior and potential hazards in Chaohu Lake sediments.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"274 ","pages":"Article 104653"},"PeriodicalIF":3.5,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144364365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Prediction of non-equilibrium transport of nitrate nitrogen from unsaturated soil to saturated aquifer in a watershed: Insights for groundwater quality and pollution risk assessment","authors":"Debao Lu ,&nbsp;Jian Ou ,&nbsp;Jinglin Qian ,&nbsp;Cundong Xu ,&nbsp;Hui Wang","doi":"10.1016/j.jconhyd.2025.104649","DOIUrl":"10.1016/j.jconhyd.2025.104649","url":null,"abstract":"<div><div>This study introduces an innovative integrated modeling framework to elucidate nitrate nitrogen migration within heterogeneous vadose zones, addressing key challenges in simulating non-equilibrium pollutant transport at the watershed scale. A novel in-situ device was developed for efficient, large-scale soil solute breakthrough curve (BTC) collection, critical for field-scale simulations. Fitting these BTCs, the Mobile-Immobile Model (MIM) (mean R² = 0.94) outperformed the Convection-Dispersion Equation (CDE) (mean R² = 0.88), underscoring the prevalence of non-equilibrium transport in the study area. Bootstrap resampling validated sample adequacy for estimating transport parameters <em>v</em> (velocity) and <em>D</em> (dispersion), with confidence intervals stabilizing below 10 %. The Ensemble improved Stream Tube Model (ESTM), incorporating Pearson Type III (P-III) distributions for transport variables (validated against lognormal; R² up to 0.92) and nitrate degradation/adsorption, significantly enhanced predictive precision. This model accurately predicted high pollutant concentrations during rainy seasons (NSE = 0.97) and reasonably estimated dry season low concentrations, despite slight overestimations attributed to sensor limitations at low moisture. When integrated with a groundwater solute transport model, the framework effectively simulated long-term nitrate dynamics in both vadose and saturated zones under fertilizer application, closely matching observations. Sensitivity analysis highlighted mean dispersion, its skewness, mean velocity, and adsorption as critical for non-equilibrium transport. Critically, by explicitly modeling <em>v</em> and <em>D</em> joint heterogeneity, our ESTM markedly outperformed traditional models in simulating early breakthrough and tailing (R² = 0.875 vs. 0.623). This research provides a robust, adaptable approach for understanding groundwater nitrate dynamics and pollutant fate across diverse environmental conditions.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"274 ","pages":"Article 104649"},"PeriodicalIF":3.5,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144312923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Preparation of novel multifunctional magnetic biochar integrating adsorption and degradation and application in printing and dyeing wastewater","authors":"Ruihui Gong ,&nbsp;Huidong Li ,&nbsp;Yuxin Liu ,&nbsp;Jiangzhe Fu ,&nbsp;Junming Yi ,&nbsp;Dongsheng Feng","doi":"10.1016/j.jconhyd.2025.104652","DOIUrl":"10.1016/j.jconhyd.2025.104652","url":null,"abstract":"<div><div>This study focuses on solving the urgent problem of water environment pollution caused by the discharge of organic dyes in high-concentration textile wastewater. A multifunctional magnetic biochar (MMBC-400) with adsorption and degradation functions was prepared by pyrolysis of corn cob and red mud demonstrating efficient handling of Malachite Green (MG). Compared with traditional adsorbents, MMBC-400 combines adsorption and catalytic degradation functions. The adsorption efficiency of MG was 99.19 %, and the adsorption capacity was 793.51 mg/g. The composite material has excellent stability and is still more than 90 % after 6 cycles. The composite material has excellent stability, and the adsorption efficiency is still greater than 90 % after 6 cycles. Kinetic and isothermal analyses showed that the chemisorption was dominated by multilayer adsorption. Meanwhile, the free radical (∙OH, SO- 4·) and non-radical (¹O₂, electron transfer) pathways were supplemented to realize the rapid degradation of MG, and the degradation efficiency was greater than 85 % after four regenerations. Characterization studies further confirmed the role of hierarchical pore structure, surface functional groups (e.g., -OH, Fe<img>O), and π-π interactions in pollutant binding. Despite the good experimental results achieved in laboratory scale, future work should address the issues of generalizable application and long-term stability in complex wastewater matrices. This work provides a sustainable strategy for dye removal through the reuse of agricultural and industrial wastes, realizing a paradigm shift from monofunctional materials to multifunctional remediation systems.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"274 ","pages":"Article 104652"},"PeriodicalIF":3.5,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144307506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Autonomous self-propelled reduced graphene oxide hydrogel-CuO@rGO micromotors for high-efficiency removal of organic dye pollutant","authors":"Zengze Liu ,&nbsp;Ziwei Zheng ,&nbsp;Yanlin Liu ,&nbsp;Xiaoqiu Yang ,&nbsp;Yangwei Chen ,&nbsp;Fang Tan","doi":"10.1016/j.jconhyd.2025.104650","DOIUrl":"10.1016/j.jconhyd.2025.104650","url":null,"abstract":"<div><div>This study featured about the synthesis of graphene oxide hydrogel-CuO@reduced graphene oxide (rGH-CuO@rGO) micromotors with core-shell structure via an ultrasonication-assisted chemical precipitation method and their application for catalytic dye degradation. The micromotors were comprehensively characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), spectroscopic techniques (Fourier transform infrared (FTIR), Raman), surface area measurement (BET), and X-ray photoelectron spectroscopy (XPS) to determine their microstructure, composition, and chemical states. Degradation performance for methylene blue (MB) was evaluated under varying conditions: reaction time (0–120 min), peroxymonosulfate (PMS) concentration (0–5 g·L⁻¹), pH (3–8), quantity of micromotors (12–24), and MB concentration (5–100 mg·L⁻¹). The removal rate of MB was achieved over 90 % within 120 min at pH 8. The micromotors demonstrated excellent catalytic efficiency, reusability and stability over four cycles. In the dual oxidant system (H₂O₂/PMS) the micromotors exhibited effective self-propulsion and stable MB removal. The generation of hydroxyl (•OH) and sulfate (•SO₄⁻) free radicals in the system was confirmed by electron paramagnetic resonance spectrometer (EPR). Ultra High Performance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry (UHPLC-QTOF/MS) was used to identify the degradation intermediates, and the possible MB degradation pathways were proposed. Moreover, the micromotors showed satisfactory performance in removing mixed dye wastewater and phenolic compound. Additionally, the low ecotoxicity of the micromotors was demonstrated by cytotoxicity assessment. This study provided a novel and valuable route to synthesizing self-driving micromotors with potential extensive applications in environmental remediation.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"274 ","pages":"Article 104650"},"PeriodicalIF":3.5,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144307505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}