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1. 题目: Enhanced adsorption of organic matter from coal chemical membrane concentrate by applying positive potential to mesoporous activated carbon fiber
文章编号: N25042006
期刊: Separation and Purification Technology
作者: Fayuan Chen, Linnan Ma, Ruihan Wang, Yun Chai, Yali Zhan, Chunmao Chen
更新时间: 2025-04-20
摘要: Efficient removal of organics from reverse osmosis concentrate (ROC) in the coal chemical industry is crucial for ensuring the stable operation of the evaporation-crystallization unit within zero liquid discharge process and the purity of the crystallized salt. Activated carbon adsorption is a straightforward and effective method; however, its slow adsorption kinetics and high regeneration energy requirements limit its broader application. Herein, we prepared mesoporous activated carbon fiber (ACF) with high specific area as electrode material, and enhanced the adsorption and desorption of organics by applying an electric potential. The organics in the ROC is primarily composed of humics, which are negatively charged, and low molecular weight neutrals. Applying a positive potential to the mesoporous ACF significantly increased the adsorption amount and rate of organic matter by 30% and 90%, respectively, compared to ACF adsorption or adsorption with a negative potential. This enhancement was attributed to the electrostatic attraction and mesoporous structure of ACF. ACF with high mesopore volume showed good removal of humics, low molecular weight neutrals and building blocks. Correlation analysis revealed that the adsorption rate was predominantly linked to the mesopores. By applying the reverse potential to the ACFs loaded with organic matter, 40–70% of the adsorbed organic carbon was desorbed back into the water within 5 min.The energy consumption for desorption of organics adsorbed by ACFs was almost three orders of magnitude lower than that for GAC desorption. This study offers a novel solution for enhancing the adsorption of organic matter from ROC.

2. 题目: Biochar alleviates nanoplastics and bisphenol A mediated immunological, neurological and gut microbial toxicity in channel catfish Ictaluruspunctatus
文章编号: N25042005
期刊: Chemosphere
作者: Qingzhi Zheng, Yufeng Zheng, Muhammad Junaid, Ming Zeng, Hongping Liao, Ye Li, Yuanqi Zhao, Qian Huang, Jun Wang
更新时间: 2025-04-20
摘要: Nanoplastics (NPs) and bisphenol A (BPA), exhibit abundant industrial applications, are produced in large volumes and ubiquitously released into the environment, posing a serious threat to ecological and human health. Biochar has been extensively studied for its ability to mitigate the negative effects of contaminants on plants. Therefore, this study aims to investigate whether biochar co-exposure with polystyrene nanoplastics (PS-NPs, size 80 nm) and BPA mitigate their toxic impacts on Ictalurus punctatus and maintain its normal growth. The I. punctatus was exposed individually to PS-NPs (0.5 mg/L) and BPA (0.2 mg/L) as well as co-exposed to PS-NPs + biochar and BPA + biochar for 7 days. Results showed PS-NPs and BPA single exposure caused tissue damage in terms of hepatocyte swelling and gut villi diffusion, and induced oxidative stress. PS-NPs and BPA single exposures led to significant changes in enzymatic activities and genetic expressions of biomarkers related to the immune system, producing inflammatory response. It also led to dysregulation of neurotransmitter enzymes (ACH, ChAT, AChE) and overexpression of neuron genes, resulting in neurotoxicity. Moreover, there was an increase in the diversity and alteration in composition of the gut microbiota (Plesiomonas, Pseudomonas), resulting in dysbiosis of the gut microbiota. However, biochar presence (0.5 g/L) reduced the accumulation of PS-NPs and BPA in fish and contributed to various degrees of mitigation for the toxic impacts of PS-NPs and BPA. Overall, biochar helped to mitigate the negative effects of PS-NPs and BPA on oxidative stress, histopathology, immune system, neurological responses and gut microbiota. This study emphasized the potential of biochar to mitigate the negative impacts of NPs and BPA on aquatic organisms.

3. 题目: High soil salinity reduces straw decomposition but primes soil organic carbon loss
文章编号: N25042004
期刊: Soil Biology and Biochemistry
作者: Mengmeng Chen, Yakov Kuzyakov, Jie Zhou, Kazem Zamanian, Shang Wang, Khatab Abdalla, Jing Wang, Xiaobin Li, Haoruo Li, Hongyuan Zhang, Kevin Z Mganga, Yuyi Li, Evgenia Blagodatskaya
更新时间: 2025-04-20
摘要: Straw incorporation is a widely recommended agronomic practice to increase organic carbon (C) in saline soil. The mechanism of straw induced priming effect (PE) on soil organic matter (SOM) decomposition is likely to be influenced by salinity, which may stimulate microbial processes and enzyme activity because of osmotic stress and nutrient resource limitation. We incubated ¹³C-labeled straw in soil for 90 d under three salinity levels: low electrical conductivity (EC_1:5) of 0.31 dS m^-1, medium EC_1:5 of 0.97 dS m^-1, and high EC_1:5 of 1.6 dS m^-1). During the first 15 d, the low salinity soil had 31% greater PE than the high salinity soil, apparently due to microbial preference for labile straw-derived C over SOM under negligible osmotic stress. This trend was reversed from day 30 onward, with medium-and high-salinity soil showing amplified PE (1.1-fold and 1.7-fold increase respectively versus low-salinity control), associated with microbial N limitation (inorganic N dropped more than 16%) and dominance of copiotrophic taxa: Proteobacteria, Bacteroidota, Ascomycota. High salinity decreased microbial biomass and diversity, and slowed down straw decomposition, which lowered necromass by 13% and increased plant-derived C by 6.9% compared to low soil salinity. Quantitative modeling demonstrated linear salinity effects on C cycling - each 1 dS m^-1 increase in soil EC_1:5 amplified the annual PE by 930 mg C kg^-1 soil year^-1 and reduced the net C balance by 3.8 g C kg^-1 soil. Therefore, high soil salinity enhances SOM loss, while increase in straw-derived C primarily comes from plant-derived C rather necromass C. Our findings make the connection between soil salinity and C dynamics in straw-remediated saline soil, which is linked to the C sequestration potential of saline lands.

4. 题目: Combining Ferroferric Oxide with a Compound Microbial Agent to Accelerate Humification during Agricultural Waste Composting
文章编号: N25042003
期刊: ACS ES&T Engineering
作者: Zuli Pan, Yanwei Liu, Zhen Jin, Yaobin Zhang
更新时间: 2025-04-20
摘要: The slow decomposition of lignocellulose is a major challenge in the aerobic composting of agricultural waste. Reactive oxygen species (ROS) generated in an aerobic–anoxic interface during composting can attack the lignocellulose structure to accelerate humification. This study attempted to produce more ROS by combining Fe₃O₄ with a compound microbial agent (CMA; B. subtilis and P. chrysosporium) (CMA-Fe) to drive the Fenton-like reaction to accelerate composting. The results revealed that the •OH concentration of the CMA-Fe group was 0.084 mmol/kg, which was higher than that of the CMA group and the control group without CMA and Fe₃O₄. Accordingly, the thermophilic phase duration of the CMA-Fe group was extended to 14 days, which was beneficial for the humification. The germination index, indicating the maturity of the compost, attained 70.72% by day 20 in the CMA-Fe group, which was significantly shorter than that of the other two groups. The analysis of the humic acid content and the cyclic voltammetry of the compost sample indicated that the addition of CMA and Fe₃O₄ accelerated the humification. Furthermore, Fe₃O₄ enriched iron-reducing bacteria capable of participating in microbially driven Fe(III)/Fe(II) redox transformations. Thus, combining iron oxides and CMA might provide a novel approach for shortening the composting period and improving the quality of compost products.

5. 题目: Biochemical heterogeneity of soil components manipulating long-term organic carbon pool buildup over mineral protection in the mollisol
文章编号: N25042002
期刊: Soil and Tillage Research
作者: Jie Li, Xuefeng Zhu, Feng Zhou, Yi Li, Xuesong Ma, Wei Zhang, Xuelian Bao, Tiantian Zheng, Zhen Bai, Hongbo He, Xudong Zhang
更新时间: 2025-04-20
摘要: Increasing evidence shows that the interaction of heterogeneous constituents with soil minerals critically controls soil organic carbon (SOC) sequestration. However, the impact of long-term fertilization on the distinct allocation of microbial- and plant-derived components in physically separated fractions is still uncertain. Using amino sugars and lignin phenols, the retention of microbial necromass and plant debris in soil particle size fractions was evaluated under 30-year chemical fertilization (NPK) application and NPK combined with manure at both low and high application rates. Amino sugars were inherently enriched in the clay, whereas lignin was preferentially accumulated in fine and coarse sand fractions, regardless of the fertilization regime. Compared with unfertilized plot, long-term NPK application enhanced amino sugar accumulation in all the particle size fractions to the same extent (ca. 23 %) but did not alter SOC and lignin concentrations, implying that the improved SOC stability after NPK application was primarily attributable to the preservation of microbial necromass rather than changes in mineral protection. Comparatively, manure applications increased SOC accumulation by 51.4–89.4 %, which was mainly associated with the enhanced allocation of lignin in sand and the hierarchical migration of microbial necromass from clay to sand fraction. High manure rates caused microbial saturation in clay fraction and, simultaneously, the preferential retention of lignin in coarse sand fraction. In conclusion, mineral-associated protection of soil heterogeneous components was attenuated during the SOC pool buildup. The inherent biochemical properties of microbial- and plant-derived components, particularly the decomposability of plant debris, primarily control long-term accumulation and turnover potential of SOC.

6. 题目: The restoration of zinc pollution in smelting site soil using nanohydroxyapatite-modified cyanobacterial biochar and its mechanism
文章编号: N25042001
期刊: Environmental Research
作者: Wentao Wu, Wanning Ye, Liu He, Mingru Wu, Jiaqi Li, Zhengbo Yue, Rui Deng
更新时间: 2025-04-20
摘要: Heavy metal pollution in the soils at smelting sites must be effectively controlled. Recent advancements in stabilization technology have shown promising results in the remediation of heavy metal-contaminated soils. In this study, nanohydroxyapatite (nHAP) and cyanobacterial biochar were co-pyrolyzed to produce nHAP-modified cyanobacterial biochar (nHAP-CBC), which was applied to remediate Zn contamination of soils at smelting sites. The remediation effect of nHAP-CBC on Zn-contaminated soil was evaluated using batch experiments, and the materials were characterized using XRD, SEM, TEM, BET, and FTIR. These analyses confirmed the uniform dispersion of nHAP on the CBC to form a stable nHAP-CBC material. The results demonstrated that nHAP-CBC effectively converted Zn from an unstable state to a stable state, achieving a 65.79% conversion rate and a 64.24% stabilization rate during toxicity characteristic leaching after 45 days of treatment. nHAP-CBC was the most effective at fixing Zn and significantly increased the organic matter (OM) content, suggesting that OM played a key role in Zn fixation. In conclusion, the nHAP-CBC developed in this study can effectively stabilize heavy metals in smelting site soils and offers promising potential for expanding cyanobacterial resource utilization.

7. 题目: Enhancing soil C sequestration through organic matter recycling: A comparative study of paddy and upland fields
文章编号: N25041914
期刊: Soil Biology and Biochemistry
作者: Hyeon Ji Song, Sihyun Park, Na-Hyun Kwon, Andrew J Margenot, Jeong-Gu Lee
更新时间: 2025-04-19
摘要: Winter cover crops are expected to increase soil organic C (SOC) stocks, but the magnitude of SOC gain could be greater in paddy fields where decomposition is constrained by anaerobic soil conditions, compared to upland fields. This study examines the impact of winter cover crop recycling on SOC accumulation over two years in South Korea. Plots were established in a rice paddy field and a nearby upland maize field, and each field was fertilized with organic or chemical inputs. In chemical treatments, where no cultivation occurred during winter, synthetic fertilizers (NPK) were applied at recommended doses for rice and maize. In organic treatments, barley and hairy vetch were grown during the winter fallow season and terminated by incorporation as organic amendments in the warm cropping season, prior to planting the annual rice or maize crop. Compared with chemical treatments, no significant effect of organic treatments on grain productivity was observed. However, organic treatments increased net primary production (NPP) by 46–81%, regardless of field conditions. The higher C inputs with organic amendments were accompanied by greater C respiration—63–73% more in paddy fields and 15–39% higher in upland fields—than with synthetic fertilizer. Net ecosystem carbon balance (NECB) increased by 343–347% in paddy fields and 15–39% in upland fields under organic amendments. Consequently, rice paddy fields with organic amendments had an annual C accumulation of 1773–2168 kg C ha^-1. Conversely, despite extensive recycling of winter cover crops, maize cultivated in upland fields still experienced an annual net C loss of 4663–7789 kg C ha^-1. Recycling organic residues as a C source in rice paddy fields promotes SOC stock accumulation in temperate regions. Conversely, in maize upland fields, where organic plant recycling alone is insufficient for C sequestration, incorporating additional biomass, such as maize stover, is essential to offset the net SOC loss.

8. 题目: The impact of water-sediment regulation scheme (WSRS) on the chemistry of dissolved organic matter in the Yellow River estuary and adjacent waters
文章编号: N25041913
期刊: Water Research
作者: Donglei Niu, Yanfang Li, Yang Tan, Chao Ma, Yulin Qi, Yanan Li, Jianhui Tang
更新时间: 2025-04-19
摘要: Dissolved organic matter (DOM) plays important roles in the global carbon cycle and aquatic ecosystem health. Estuaries are critical zones connecting land and ocean in which DOM experiences dispersion, transformation, degradation, deposition, etc. The Water-sediment regulation scheme (WSRS) was implemented in Yellow River (YR) and approximately half of annually sediment and a quarter of annually water were poured into estuary in around 20 days. Meanwhile, huge amounts of DOM were discharged into Yellow River estuary (YRE) rapidly, but their processes and fates in YRE and adjacent seas are unclear. This study aims to investigate the molecular and spectrum compositions of DOM and its associated transformation mechanisms around the YRE and its adjacent sea before (from June 8 to 12, 2022) and after (from July 18 to 22, 2022) the WSRS. A relatively greater amount of highly unsaturated compounds and terrestrial-derived DOM was found with higher aromaticity and humification degree after WSRS, by bulk geochemical techniques, optical spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) techniques. High levels of less photodegraded DOM were found in the estuarine region after WSRS, due to the rapidly pouring huge amount of fresh water and sediment into YRE. The high suspended sediment concentration facilitates the sorption of dissolved organic carbon (DOC), especially those sulphur-containing compounds in DOM which decreased both in the relative intensity and number. However, in the long term, WSRS may lead to an increase of DOC in the water column. Along with the YR plume and coastal current, DOM was transported from the YRE to Laizhou Bay to the south and arrived at Bohai Strait to the east. Overall, this research provides valuable insights into estuary DOM variations induced by the intensive dam-orientated regulation in a short term.

9. 题目: Degradation of 4-chloroaniline in sulfidated nanoscale zero-valent iron loaded on biochar activated persulfate system: Batch and column experiments
文章编号: N25041912
期刊: Separation and Purification Technology
作者: Yuyuan Sun, Qian Jiang, Jing Song, Linchao Hu, Zichen Yan, Junhao Zhang, Rui Liu, Jingchun Yan
更新时间: 2025-04-19
摘要: Nanoscale zero-valent iron (nZVI) is widely utilized as an efficient transition metal material for persulfate (PS) activation. However, the intrinsic agglomeration and the passivation layer on nZVI surface limits its application in in-situ chemical oxidation (ISCO). Therefore, we synthesized sulfidated nanoscale zero-valent iron loaded on biochar (S-nZVI/BC) composite to enhance PS activation for efficient degradation of 4-chloroaniline (4-CA) under both batch and column experiments. S-nZVI/BC composite prepared at a S/Fe molar ratio of 1:5 and biochar pyrolysis temperature of 500 ℃ exhibited the optimum PS activation performance. The degradation rate of 4-CA was 98.86 % with the reaction rate constant of 0.684 min⁻¹ in batch experiment. Meanwhile, the degradation rate of 4-CA was achieved 58.08 % in column experiment with a M_S-nZVI/BC/M_sand mass ratio of 1:200 and flowing rate at 1.0 mL·min⁻¹. By forming a sulfide species layer on the surface of nZVI, the yield of ROSs, the stability of nZVI/BC and the utilization efficiency of PS were enhanced in relation to the facilitated electron transfer property and the cycling of Fe²⁺. The electron paramagnetic resonance (EPR) analysis demonstrated the presence of SO₄^•-, •OH and O₂^•- and the contributions to the 4-CA degradation were 29.85 %, 44.93 % and 24.08 % verified by quenching experiment. 4-CA was gradually deaminated to monochlorobenzene, acetic acid, acetaldehyde, oxalic acid and ultimately mineralized to CO₂ and H₂O with the total organic carbon (TOC) mineralization rate of 67.96 %, and the ecological toxicity of the system was significantly diminished from toxicity assessment. This study demonstrated insights into the enhancement mechanism of S doping in S-nZVI/BC activated PS system and provided a potential for the remediation of 4-CA contaminated groundwater in ISCO.

10. 题目: Adsorption of natural organic matter and divalent cations onto / inside loose nanofiltration membranes: Implications for drinking water treatment from rejection selectivity perspective
文章编号: N25041911
期刊: Water Research
作者: Hao-yu Guo, Xiao-mao Wang, Kunpeng Wang, Shuming Liu
更新时间: 2025-04-19
摘要: Loose nanofiltration (LNF) membranes hold great promise for the selective rejection of natural organic matter (NOM) while maintaining mineral salts to produce high-quality drinking water. Nevertheless, the rejection selectivity performance is not only determined by the inherent properties of membranes but also influenced by the feed water compositions. This study explored the inevitable adsorption of NOM and inorganic ions onto and inside membrane materials, which in turn altered the charge properties of LNF membranes, thereby affecting the rejection selectivity. Zeta potential measurements, X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry technique were employed to characterize solute adsorption on the membrane surface and within the membrane pores. Filtration experiments using synthetic and natural waters were conducted to assess the contribution of electrostatic effects and evaluate the membrane rejection performance. Results revealed that LNF membrane surfaces during filtration were readily coated by NOM molecules, probably via hydrophobic interactions, which in turn adsorbed divalent cations that actually determined the net charge density on the membrane surface. Additionally, NOM adsorption within the membrane pores largely altered pore charge properties, particularly of the sulfonated polyethersulfone membranes (e.g. NTR7450), where deprotonated sulfonic groups otherwise contributed to a high charge density. These interactions among NOM, divalent cations and membrane materials greatly reduced charge density on the membrane surface and largely diminished charges in pores, leading to decreased rejection of both NOM and mineral salts, as well as the mitigation of co-ion competition effects. Nevertheless, the UA60 membrane, having a molecular weight cut-off of ∼1,000 Da, rejected NOM by ∼70% while maintaining ∼95% bicarbonate and ∼65% hardness ions in the treated water, demonstrating fairly good selectivity. These findings offer valuable insights for optimizing LNF membranes to improve the safety, chemical stability and palatability of treated drinking water.

11. 题目: Adsorption of Cu(II) and Pb(II) Onto a Histosol in Comparison with Its Humin Fraction
文章编号: N25041909
期刊: Water, Air, & Soil Pollution
作者: Quynh Nguyen-Phuong, Stéphanie Sayen, Marie Ponthieu, Béatrice Marin, Emmanuel Guillon
更新时间: 2025-04-19
摘要:

This study investigated the adsorption of Cu²⁺ and Pb²⁺ onto a histosol (peat soil) as a function of pH and compared it to their adsorption onto its humin fraction. The use of the NICA-Donnan model, considering humic acid and humin as soil reactive solid phases and fulvic acid as reactive dissolved organic matter, satisfactorily described the adsorption behaviour of Cu²⁺ and Pb²⁺ onto histosol. Both metals were adsorbed mainly via carboxylic sites of both solid phases with a higher contribution of humic acid. Nevertheless, this study highlighted the significant role of humin, accounting for up to 37% of the overall metallic cation retention onto histosol. Thus, if not the most reactive solid organic matter fraction in soils, humin contributes notably to metal retention. Its contribution should thus be considered as a significant solid organic matter component of soils for a better description and prediction of metal trace element adsorption.

12. 题目: Iron-modified biochar enhanced nitrogen retention during composting:bridging chemisorption and microbiome modulation
文章编号: N25041908
期刊: Chemical Engineering Journal
作者: Ruolan Tang, Sheng Yao, Yan Liu, Tianyu Ren, Jingyuan Ma, Xiaoyan Gong, Guoxue Li, Ruonan Ma, Jing Yuan
更新时间: 2025-04-19
摘要: Nitrogen loss during composting remains a critical challenge, leading to diminished compost product quality and elevated environmental risks from reactive nitrogen emissions. While biochar demonstrates potential in mitigating nitrogen loss, its efficacy is constrained by inherent limitations including alkaline pH properties. This study developed an iron-modified biochar (BCF, 1.9 % Fe loading) and systematically evaluated its performance against unmodified biochar (BC) in regulating nitrogen dynamics during composting, with mechanistic insights elucidated through microbial community profiling and functional gene quantification. Key findings revealed that both BC and BCF treatments prolonged thermophilic phase duration (≥55 °C for 16–20 days) and yielded pathogen-free compost meeting maturity criteria. Notably, BCF outperformed BC by reducing cumulative NH₃ emissions by 30.0 % and total nitrogen loss by 20.1 %. The superior nitrogen retention capacity of BCF was attributed to two synergistic mechanisms: (1) Increased specific surface area (SSA: 27.88 vs. 10.97 m²/g in BC) and functional groups (C-O, Fe-O, –OH, –COOH), facilitating ammonium adsorption and chemical stabilization to support biotic processes; (2) Biotic activation through selective enrichment of nitrogen cycle taxa (e.g., Terrisporobacter) and upregulation of functional genes, including nitrification markers (amoA: +103.29-fold, hao: +1456.87-fold, nxrA: +11.85-fold) and nitrogen fixation determinants (nifH: +18.83-fold). These findings establish that iron-functionalized biochar orchestrates coupled physicochemical and microbiological pathways to enhance nitrogen conservation, providing a scalable strategy for sustainable compost production

13. 题目: Destruction of sludge floc and extracellular polymeric substances structure by natural deep eutectic solvent with thermal treatment assistant for synergistic promotion of dewaterability and protein recovery from waste-activated sludge
文章编号: N25041907
期刊: Journal of Environmental Chemical Engineering
作者: Xinlin Chen, Jin Huang, Jing Zhao, Xuejun Hu, Junfeng Zhang, Xiaolong Yu, Chuan Peng
更新时间: 2025-04-19
摘要: The significant hydrophilicity of extracellular polymeric substances (EPS) in waste-activated sludge is a major obstacle to effective dewaterability. This research proposed a natural deep eutectic solvent (NADES), synthesized with choline chloride (ChCl) as the hydrogen bond donor (HBD) and citric acid (CA) as the hydrogen bond acceptor (HBA). When combined with thermal treatment, NADES effectively enhanced the dewaterability and protein recovery efficiency of sludge. The capillary suction time (CST) of the sludge cake dropped from 28.2 s to 21.1 s, and the water content (Wc) reduced from 70.49% to 57.49% after adding 1.5 mL of NADES and heating to 80 °C for one hour. Simultaneously, the protein concentration in the treated sludge increased to 315.2 mg/L. These characterizations by particle size, zeta potential, scanning electron microscopy (SEM), three-dimensional excitation emission matrix (3D-EEM), and X-ray photoelectron spectroscopy (XPS) indicated that the alterations in the physicochemical properties of the sludge and the compositions of EPS were due to the neutralization of the negative charges on the sludge surface as well as the degradation of EPS. Density functional theory (DFT) calculations further reveal that NADES enhances protein solubility and reduces the activation energy for peptide hydrolysis. This study demonstrates that using NADES in conjunction with thermal treatment is an eco-friendly approach to enhancing the dewaterability of sludge and the efficiency of protein recovery.

14. 题目: Contradictions in Dissolved Black Carbon Research: A Critical Review of its Sources, Structures, Analytical Methods, and Environmental Behaviors
文章编号: N25041906
期刊: Environmental Pollution
作者: Lijun Fan, Tiancheng Han, Xianxing Huang, Yukai Zhang, Weiwei Zhai, Daoyong Zhang, Xiangliang Pan
更新时间: 2025-04-19
摘要: Dissolved black carbon (DBC) represents the most active component within the black carbon (BC) continuum and plays a vital role in the global carbon cycle and the removal of inorganic and organic contaminants due to its prolonged residence time and unique condensed aromatic structure. Significant progress has been made in understanding DBC source, molecular structure, analytical methods, stability, and environmental behavior, particularly its photochemical and microbial transformation. However, substantial uncertainties persist, including ambiguities in its definition, limitations in isolation and quantification methods, and unidentified sources. These limitations have led to lots of inconsistencies regarding its stability, environmental transport pathways, and transformation mechanisms. This review critically examines the current landscape of DBC research, with a focus on: (1) key contradictions in DBC cycling processes, including debates over its recalcitrance, mismatched isotopic signatures, and imbalances in the marine DBC budget; (2) limitations for DBC isolation and quantification methods in natural environments; and (3) photochemical and microbial transformation processes, and its interactions with environmental pollutants. By synthesizing recent insights, this review aims to enhance the understanding of DBC’s structures, turnover, and environmental behavior, as well as its implications for the global carbon cycle. To address existing challenges, future studies are suggested to prioritize resolving these contradictions, developing standardized analytical approaches, and achieving a clearer elucidation of DBC cycling processes across diverse environments.

15. 题目: Ozone-mediated carboxylation: a strategy for enhanced organic matter removal via in-situ crystallization of hardness ion
文章编号: N25041905
期刊: Journal of Cleaner Production
作者: Keqian Li, Yujia Han, Yi Chen, Zhihao Fu, Heng Quan, Yadong Wang, Yabo Shang, Juan Shi, Pengkang Jin, Xin Jin
更新时间: 2025-04-19
摘要: Under increasingly stringent environmental regulations, the high concentrations of inorganic ions and organic contaminants in reverse osmosis concentrate pose a serious challenge to achieving zero discharge of wastewater. To address this issue, a hybrid crystallization and ozonation (HCO) process was developed for simultaneous removal of hardness and organics from reverse osmosis concentrate. The positive interplay between ozone and Sodium hydroxide (NaOH) dosage exhibited remarkable performance, achieving removal efficiencies of 59.7% for chemical oxygen demand (COD), 60.6% for UV₂₅₄ absorbance, 80.2% for calcium (Ca), and 99.8% for magnesium (Mg). The reduction in fluorescent and functional groups indicated effective removal of aromatic substances and oxygen-containing groups. Furthermore, molecular-level transformation of organic compounds showed saturation of compounds and diminution of oxidizing carbon by HCO. Visualization of molecular formula distribution indicated higher oxidation capacity of HCO compared to ozonation as evidenced by lower double-bond equivalents (DBE) value and increased carboxyl groups in the products. Crystals analyses identified calcite (CaCO₃) and brucite (Mg(OH)₂) as dominant phases, with surface-adsorbed organic carbon qualified via carbon species analysis, demonstrating effective co-precipitation and adsorption of organic matters. Consequently, the beneficial role of increased carboxyl groups and the significant influence of Mg crystals for organics removal were demonstrated. The presence of hydroxyl and chlorine radicals (•OH, •O₂^-, •Cl, •Cl₂^-) were further confirmed, contributing to the advanced oxidation of organic substances. These findings elucidated the mechanism by which HCO facilitates the simultaneous removal of organics and hardness ions through a synergistic effect involving ozone-mediated carboxylation and ion crystallization. This study offers valuable insights for achieving efficient co-removal of organics and hardness within a streamlined treatment process.

16. 题目: Electrochemical Characterization of Pyrogenic Carbons: Implications for Degradation of Groundwater Contaminants with Carbon-Based Amendments
文章编号: N25041904
期刊: Environmental Science & Technology
作者: Jeffrey M Hudson, Paul G Tratnyek
更新时间: 2025-04-19
摘要: Pyrogenic carbons (PCs) are important mediators of biogeochemical redox reactions and contribute to contaminant degradation in some remediation methods. Contaminant degradation by electron transfer from PC is influenced by its electron conductivity and storage capacity, and atom transfer reactions involving atomic hydrogen, but resolving their contributions is difficult. In this study, we developed a method to modify working electrodes with agarose-stabilized thin films of PCs and used them to characterize PC reactivity using 2,4,6-trinitrotoluene (TNT) as a model contaminant and several electrochemical methods. Chronoamperometry showed that TNT reduction rates increase with increasing PC temperature, and electrochemical impedance spectroscopy showed that this is because the heterogeneous electron transfer rate constants (k⁰) are inversely correlated to resistivity (R_p) of the PC films. As a result, PCs like biochars, which have higher charge transfer resistance (R_ct), give lower TNT reduction rates, whereas lower R_ct PCs like activated carbons give faster TNT reduction. Current from reduction of H₂O/H⁺ to H₂ (HER) was significant only for low R_p PC-films on Pt working electrodes. The reactive intermediates involved in HER react preferentially with quinonoid moieties on the PC, thereby competing with and limiting TNT reduction at low overpotentials (<ca. −0.6 V). Overall, contaminant reduction on PCs is more favorable by electron transfer than H atom mediated reactions under the conditions of this study.

17. 题目: Photodegradation mechanism of organic contaminants mediated by chlorinated algal organic matter
文章编号: N25041903
期刊: Water Research
作者: Dong Wan, Chengjie Yu, Yafei Zhao, Gaofei Song, Wujuan Mi, Yuxuan Zhu, Changzi Liu, Yonghong Bi
更新时间: 2025-04-19
摘要: Algal organic matter (AOM) significantly influences the photochemical behavior of dissolved organic matter in aquatic environments. This study investigated the effects of chlorination on the photophysical and photochemical properties of AOM derived from Microcystis aeruginosa, compared these alterations with those observed for natural organic matter (NOM), and examined their impact on the photodegradation of organic contaminants, with a particular focus on N,N-diethyl-m-toluamide (DEET) as a model substrate. The results demonstrated that chlorination substantially altered the photochemical reactivity of AOM. AOM and NOM exhibit distinct reactivities, reflecting their varied molecular compositions and functional groups. Specifically, chlorination reduced the aromaticity (SUVA₂₅₄ decreased by ∼42%) and molecular weight (decreased by ∼30%) of AOM, resulting in a shift of fluorescence peaks to lower wavelengths. It also enhanced the formation of singlet oxygen (¹O₂) and hydroxyl radical (^•OH). Chlorinated extracellular organic matter (EOM) exhibited a remarkable increase in ^•OH quantum yield, with a 200-fold enhancement at a high free available chlorine (FAC) dose (FAC/TOC ratio of 2.0). The photodegradation of DEET, involved H-abstraction and hydroxylation by ^•OH, was significantly accelerated in chlorinated EOM, highlighting the critical role of chlorinated AOM in driving photosensitized degradation processes. The findings emphasized the role of chlorination in altering AOM's photochemical properties, with significant implications for the enhanced transformation of contaminants in natural and engineered aquatic systems.

18. 题目: Polycyclic aromatics in the Chang’E 5 lunar soils
文章编号: N25041902
期刊: Nature Communications
作者: Guangcai Zhong, Xin Yi, Shutao Gao, Shizhen Zhao, Yangzhi Mo, Lele Tian, Buqing Xu, Fu Wang, Yuhong Liao, Tengfei Li, Liangliang Wu, Yunpeng Wang, Yingjun Chen, Yue Xu, Sanyuan Zhu, Linbo Yu, Jun Li, Ping'an Peng, Gan Zhang
更新时间: 2025-04-19
摘要:

Polycyclic aromatics are ubiquitous in the interstellar medium and meteorites, yet the search for lunar polycyclic aromatics remains a significant challenge. Here, we analyze Chang’E-5 lunar soil samples, revealing polycyclic aromatic concentrations of 5.0–9.2 µg/g (average: 7.4 ± 1.4 µg/g). Their aromatic structures are highly condensed, comparable to ~4 nm graphene sheets, and distinct from terrestrial analogs, such as wood char, soot and kerogen. While meteorite impacts are the most likely sources, the stable carbon isotope composition of polycyclic aromatics in Chang’E-5 lunar soil (δ¹³C: −5.0 ± 0.6‰ to +3.6 ± 1.3‰) is more enriched in ¹³C compared to that in meteorites. This enrichment suggests a de novo formation mechanism during meteorite impacts, involving the conversion of non-aromatic organic matter—which is more enriched in δ¹³C—into polycyclic aromatics. This process may play a significant role in carbon accretion in lunar regolith, as the resulting polycyclic aromatics are more stable and resistant to degradation compared to smaller organic molecules (e.g., amino acids), which are largely destroyed during impact events.

19. 题目: Efficient removal of Cu2+ on Medulla Tetrapanacis-based modified biochar: adsorption performance, mechanisms and recycling for fabrication of supercapacitor electrodes
文章编号: N25041901
期刊: Chemical Engineering Journal
作者: Zepeng Liu, Chunbo Dai, Yueyao Hu, Jie Zhang, Yuxin Wang, Liping Zhang, Ping Ye, Tongtong Zhang, Ying Guan, Hui Gao
更新时间: 2025-04-19
摘要: Achieving high-capacity removal of Cu²⁺ from effluent remains challenging nowadays. Hence, high-performance calcium chloride modified Medulla Tetrapanacis based biochar (MBC) was prepared by simple impregnation treatment and tube furnace carbonization. The results of sorption experiments confirmed that the MBC obtained at 900 °C (MBC3) possessed the highest sorption under specific conditions (pH = 6 at 0.2 g/L). MBC3 showed the highest fitting to the pseudo-second kinetic model and the Langmuir model (R² = 0.996, 0.947). The fitted MBC3 achieved the maximum adsorption of Cu²⁺ of 945.6 mg/g, being 2.25 times higher than the adsorption of unmodified biochar (BC). Multiple mechanisms including precipitation, ion exchange and surface complexation were evidenced to be associated with the excellent sorption properties of MBC3. Considering the potential hazards of enriched Cu, MBC3 after sorption was reused as ReBC/Cu for preparing supercapacitor electrodes through a facile hydrothermal method (180 °C, 24 h). The adsorbed Cu elements were found to be mainly loaded as oxides in ReBC/Cu. It was calculated that the ReBC/Cu electrode displayed a specific capacitance of 142.5 F/g at 0.5 A/g, which was 49.01 % enhancement compared to that of the unused pristine biochar. This study combines biochar-based adsorption with the preparation of supercapacitor electrodes, which not only achieves efficient copper removal from water, but also provides a promising option for the post-treatment of copper-rich waste adsorbents.

20. 题目: Biochar plays multiple roles in BPA/persulfate degradation system
文章编号: N25041810
期刊: Journal of Environmental Chemical Engineering
作者: Xing Yi, Xiao Chen, Shaojun Jiang, Yuehong Shu
更新时间: 2025-04-18
摘要: Biochar is widely used as a persulfate (PS) activator for degrading organic pollutants in advanced oxidation processes (AOPs). However, apart from a catalyst for PS activation, biochar, as organic matter (OM) itself, its role as a degraded target as well as a sorbent for target pollutants in biochar/PS systems requires further clarification. The bulk biochar (BC), biochar-derived dissolved organic matter (BDOM) and biochar-derived particulate organic matter (BPOM) were prepared at 300 °C, 500 °C, and 800 °C and well characterized to evaluate their efficacy of sorption and activation capacity, as well as their potential for PS consumption. The results showed that biochar and its derivatives exhibited the best degradation efficacy at pyrolysis temperature of 800 °C. With DOM removed, 800BPOM showed higher BPA removal rate (97.5%) as compared with 800BC (84.8%) in the pre-sorption/degradation systems, owning to the superior sorption and activation capacity. Moreover, less 800BPOM (13.2%) was degraded by PS as compared with 800BC (17.4%), which was also attributed to the removed DOM. Although 800BDOM could also activate PS and degrade BPA with 26.6% of removal rate, 50% of 800BDOM itself was degraded by PS and led to the unnecessary PS consumption. Quenching experiments, electron spin resonance (EPR), and surface functional group analysis indicated that radical pathway (mainly •OH) and non-radical pathway (¹O₂ and graphite carbon) together contributed to BPA degradation in 800BPOM/PS and 800BC/PS systems. The results can potentially provide insights in biochar activated PS-AOPs for organics degradation.