Heavy metal contamination in mariculture sediments threatens the ecological environment and human health. Therefore, this study systematically investigated the spatiotemporal distribution, geochemical speciation, and ecological risks of Cu, Pb, Zn, Cr, and Cd in surface and core sediments of traditional mariculture areas across the Sanggou Bay, Yellow Sea. The results indicated that heavy metals in surface sediments were primarily concentrated in the central area with seasonal migratory patterns (except Cd) in the Sanggou Bay. The Cu and Pb presented an increasing and then decreasing trend, while Zn, Cr, and Cd fluctuated constantly in core sediments. And Cu, Zn, and Cr predominantly existed in residual fraction, while Cd and Pb were mainly present as acid-soluble and reducible fraction, respectively. Correlation analysis and principal component analysis revealed that Cu, Zn, Pb, and Cr showed similarities and mainly originated from local aquaculture activities, whereas Cd was closely related to atmospheric deposition. Furthermore, the pollution degree and ecological risks showed that although Cd presented the lowest concentration (0.181mg/kg), it exhibited the highest degree of pollution (PN = 3.1) and ecological risk (RI = 1356). Overall, the environmental quality of Cu, Zn, Pb, and Cr was relatively clean in study area, but Cd posed potential ecological impacts requiring prioritized attention. This research provides a robust scientific foundation for the prevention and control for heavy metal contamination in marine aquaculture areas and sustainable development.

Pyrite (FeS2) formation has been proposed as an effective strategy for achieving permanent sulfide immobilization in contaminated aquatic environments, but the slow nucleation rate at ambient temperatures limits its practical application. Although Ni2+/Co2+ are known to accelerate the formation of FeS2 and Ni exhibits stronger catalytic effects, the underlying acceleration mechanisms still remain ambiguous. This work systematically investigated the catalytic action of Ni and Co by combining kinetic experiments, aqueous speciation analysis, solid-phase characterization, and density functional theory (DFT) calculations. The results demonstrate that FeS2 forms via the reaction between [FeS] species derived from mackinawite (FeS(m)) and polysulfide (Sn2- ), with pentasulfide (S52- ) being identified as the dominant reactive species. Compared with pure FeS, Ni/Co doping reduced the apparent reaction order and activation energy, and increased the selectivity to FeS2, as revealed by quantitative kinetic analysis. Both metals are incorporated into mackinawite through a three-step pathway: adsorption as [M(H2O)6]2+, ligand exchange to [M(H2O)5(HS)]+, and final substitution into (Fe,M)S solid solutions. The electrons released during incorporation drive the ring-opening of elemental sulfur (S8) to generate reactive S52- . DFT calculations indicate that both Ni and Co doping lower the density of states (DOS) of FeS and shift Fe d-band centers toward the Fermi level, thereby enhancing S52- adsorption. However, Co doping induces excessive binding stability of S52- , which hinders subsequent transformation and raises the reaction barrier. Our findings fundamentally clarify the catalytic mechanisms of Ni and Co, providing guidance for optimizing rapid sulfide immobilization strategies.

Co-sintering contaminated dredged sediment (DS) with red mud (RM) into ceramsite is an effective route for the integrated management of two large-volume industrial and hazardous waste streams. However, the regulation of toxic metal behavior (e.g., volatilization and immobilization) by sintering parameters remains insufficiently understood, and the value-added utilization of the product is still limited. Therefore, this study developed a synergistic co-sintering strategy to clarify how atmosphere (N2 vs. air), temperature, time, and DS/RM ratio jointly control the behavior of As, Cd, Cr, Cu, Pb, and Zn along the gas–particle–solid pathway, and concurrently explored the resulting ceramsite as a Cd(II) adsorbent. The results showed that an N₂ atmosphere strongly promoted volatilization removal of Cd and Pb (up to 82.6 %–87.7 %) and promoted the derivatization of metals into residual fractions (>89.6 %), whereas an air atmosphere favored As(V) generation but increased Cr mobility via Cr(VI) formation. The co-sintering of RM and DS greatly promoted the volatilization of Pb and Cd, while enhancing the retention of As and Cr. An operating window of approximately 1150 °C and 10–15 min balanced microstructural densification with suppression of As re-volatilization and excessive Cr(VI) generation. Moderate RM addition (e.g., DS/RM = 60:15) optimized the trade-off between volatile emissions and solid-phase retention by enhancing Fe–Al-bearing stabilizing phases without excessively increasing As and Cr contents or leaching in the ceramsite. The selected ceramsite exhibited a Cd(II) adsorption capacity of 35.6 mg/g (pH = 7) based on precipitation, electrostatic attraction, and complexation. Overall, this work established a mechanistic, parameter-based framework for process-window design in DS/RM co-sintering and demonstrated a waste-to-resource pathway for safely transforming hazardous solid wastes into functional materials for toxic-metal wastewater treatment.

Advanced oxidation processes (AOPs) represent promising water treatment technologies. Nevertheless, their practical applications are hampered by multiple challenges, including facile diffusion and quenching of reactive oxygen species (ROS), poor selective oxidation performance, as well as deteriorated activity and stability of catalysts. Catalysts constructed under nano-confinement exhibit distinctive physicochemical properties and catalytic behaviors, which can effectively address the technical bottlenecks of conventional AOPs.This review systematically investigates the research advances of nano-confinement-mediated AOPs. First, a comprehensive bibliometric analysis is conducted to clarify the evolutionary trajectory and shifts of research hotspots within the nano-confinement field. Subsequently, the alterations in microscopic reaction mechanisms induced by nano-confined architectures during oxidation reactions are summarized. Nano-confined structures are categorized, and synthetic routes for nano-confined catalysts are thoroughly reviewed and reclassified as a core focus of this work. Finally, the state-of-the-art applications of nano-confined catalysts in AOP-based wastewater remediation are outlined, followed by a discussion on urgent unresolved challenges and prospective research directions.In summary, this review elaborates on the fundamental mechanisms and cutting-edge applications of nano-confinement-based advanced oxidation technologies for wastewater treatment. It aims to offer theoretical guidance for subsequent research on nano-confined catalysts and facilitate further development of this research field.

Large-scale kelp cultivation is pivotal for the global circular economy and climate regulation. However, frequent ecological disturbances in mariculture areas have underscored the need to understand microbial community dynamics and their role in biogeochemical cycling. This study systematically characterized the microbial communities within the seawater and sediment of two representative kelp farming areas in the North Yellow Sea via high-throughput sequencing, incorporating regional, seasonal, and farming models. The results indicate that the microbial diversity in Sanggou Bay is relatively low, which may suggest a potential risk to ecological stability. In contrast, the Changdao region maintains a more complex community structure, which may confer a stronger buffering capacity. While kelp farming activities appear to influence the seasonal succession of planktonic microorganisms, the microbial response in sediments exhibits a lag effect and cumulative changes. Furthermore, seasonal variations significantly modulate the functional potential for nutrient cycling, particularly the cycles of nitrogen and phosphorus. Notably, polyculture models are associated with increased relative abundance of predicted functions and enhanced network stability, which could foster a more robust metabolic environment and improve resilience to environmental disturbances. These findings provide critical insights for optimizing kelp farming strategies and contribute to mitigating potential ecological risks in marine aquaculture.

This study comprehensively investigated the nutrient removal mechanisms of Chlorella sp. in authentic aqua-culture wastewater, while also examining the dynamic shifts within its symbiotic microbial community. The results showed that the microalgae exhibited robust growth in the wastewater, effectively reducing concentrations of ammonium nitrogen, nitrate nitrogen, and phosphate with removal efficiencies of 95.0 %, 93.2 %, and 91.7 %, respectively. Fluctuations in pH during the initial cultivation period indicated a cyclical interplay between heterotrophic microbial activity and microalgal photosynthesis. In the later stages, enhanced synthesis of Chlorella carotenoids was correlated with deteriorating water quality and the onset of oxidative stress. Initially, the microbial community was dominated by organic matter degradation, nitrate reduction, and fermentation. However, as cultivation progressed, metabolic activities shifted towards the photoassimilation of inorganic nutrients. The Chlorella sp. symbiotic system facilitated a rapid succession of the microbial community, which was characterized by frequent bacterial population changes, ultimately leading to a unique, temporally stable community structure. The initially diverse microbial population was progressively supplanted by more adaptive bacterial strains, achieving a steady state by the seventh day. Notably, Alcaligenaceae demonstrated exceptional adaptability compared to other genera, underscoring its pivotal role within the Chlorella sp. symbiotic system. This research provides valuable theoretical insights into algal-bacterial interactions and highlights their potential for application in water quality remediation.

Rising cadmium (Cd) contamination poses significant threats to crop productivity, quality, and human health. To address this, nano-enabled techniques have recently gained attention for their potential to enhance crop yields and remediate contamination due to heavy metals. This study explores the efficacy of silicon dioxide nano- particles (SiO2 NPs) in mitigating the effects of cadmium sulfide (CdS) NPs in spinach. Field experiments were conducted growing spinach plants subjected to cultivation with 1 mg/L CdS NPs contamination, with foliar application of SiO2 NPs at concentrations of 1, 20, and 100 mg/L. The phenotypic, biochemical, and metabolic responses of the plants to stress conditions were examined following exposure to CdS and SiO2 for four weeks. The results showed that SiO2 NPs increased the fresh and dry weights of both roots and shoots. Furthermore, CdS NPs exposure reduced chlorophyll content by 66.76 %, whereas SiO2NPs co-exposure increased chlorophyll levels by up to 42 % compared to the CdS NPs and control groups. However, elevated malondialdehyde (MDA) levels were observed in leaves for the CdS-only group and roots for all treatments indicating oxidative stress was most pronounced for the CdS case. Results demonstrated that SiO2 application significantly reduced Cd accumulation in spinach by up to 34.92 %. Also, enhanced mineral accumulations were recorded in both roots and shoots, whereas decreased levels were found in the co-exposure groups, except for Zn. The exposure to SiO2 resulted in upregulation of metabolites including galactonic acid, d-aspartic acid and others, and UDP-dgalactose was downregulated in the group exposed only to CdS NPs. The upregulation of these metabolites by SiO2 NPs demonstrates their mitigating effect against CdS NPs induced stress. This work enhances understanding of phenotypic and metabolic alterations induced in spinach by CdS and SiO2 NPs, and independently and through their co-exposure. Overall, our findings indicate that Cd contamination can be reduced in spinach using SiO2 NPs when applied at low levels, and the mechanisms are discussed.

Cadmium (Cd) contamination is a significant global environmental issue due to its toxic effects on plant and human health. However, the specific impacts of cadmium sulfide nanoparticles (CdS NPs) on plants, including the underlying molecular mechanisms, toxicity, uptake, and accumulation, remain poorly understood. This study explored the influence of CdS NPs on spinach plants by combining phenotypic and metabolomics analyses. Spinach plants were exposed to CdS NPs (0.005, 0.01, 0.2, 0.4, and 1 mg/L) and Cd ions (0.1 mg/L) through foliar and root for three weeks. Results indicated that root exposure had a more pronounced impact on biomass, plant height, leaf structure, and chlorophyll content than foliar exposure. Cd and CdS NPs uptake in root and shoot were confirmed through Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Energy-Dispersive X-ray Spectroscopy (EDS), respectively and/or jointly. Metabolomics analysis revealed that CdS NPs altered nitrogen metabolism, carbon metabolism, tyrosine metabolism, and isoquinoline alkaloid biosynthesis, which are crucial for plant growth, development, and survival. These findings enhance comprehension of the intrinsic phenotypic and metabolic alterations induced by CdS NPs in spinach plants.

Phosphorus (P) input from major rivers is considered to be vital for marine nutrient balance, supplying bioavailable-P. However, the potential for bioavailable-P carried by suspended particulate matter (SPM) to be transported to the open sea is unclear. This study investigated bioavailable-P distribution and transport on SPM at the Yellow River estuary using P fractionation, Ivanoff method, and 31P-NMR spectroscopy. Results indicate that the gravity sedimentation time of SPM is strongly negatively correlated with particle size (p < 0.05, r > 0.8). P fractionation showed NaOH-P and organic P (OP) in fine-sized SPM (settled after 200 min) were 1.84 and 1.69 times higher than in SPM settled at 10 min. However, 31P-NMR analysis demonstrated that the OP carried by fine-sized SPM was mainly orthophosphate monoester (low bioavailability and immobile) and pyrophosphate, accounting for over 95 % of biogenic-P (excluding orthophosphate). Ivanoff method found pyrophosphate in SPM would be eluted by estuarine salinity, increasing dissolved non-reactive P to 0.357 mg L-1. Specially, dissolved reactive P adsorption experiments showed fine-sized SPM is a weak source of dissolved reactive P in water column, while coarse-sized SPM is strong. It proved that NaOH-P in fine-sized SPM is more bio-unavailable Si-Al/Fe/Mn-P. Therefore, there is few bioavailable-P that can be carried by fine-sized SPM and transported over long distances to the open sea to alleviate nutrient imbalance in the Bohai Sea.

The release of nitrogen (N) and phosphorus (P) from coastal sediments is vital to the evolution of coastal water quality. In this study, the release of N and P from coastal sediments in a heavily polluted river was studied using single-factor experiments and sequential extraction of N and P from sediments. The experimental results showed that N and P from the coastal river sediments reached the release-absorption equilibrium after the 42nd and 14th day, respectively. The release of N and P from heavily polluted river sediments in coastal zones is affected by resuspension, salinity, dissolved oxygen, and temperature. The results showed that resuspension had the greatest impact on the release of N and P from heavily contaminated coastal river sediments into the overlying water. In addition, the release of P, NO3- and NO2- from sediments is most sensitive to changes in temperature, while the release of total N and NH4+ is most sensitive to changes in salinity. Unlike in lake sediments, high dissolved oxygen concentrations inhibit the release of NH4+ from extensively contaminated coastal sediments. Ion-exchangeable forms of N and inorganic P are the most susceptible to release from external environmental factors. These findings will aid in the management and control of heavily polluted coastal rivers.

The Yellow River is an important agricultural production base in China, plays a key role in terrestrial sea transport and nitrogen transformation. However, the reason for the transient nitrogen increase in the lower Yellow River remains unclear. This study explored the contributions to transient nitrogen elevation from the water column, suspended particulate matter, surface sediments in the lower Yellow River, and washland soils along it throughout the water and sediment regulation event in 2023. Results indicated that the average dissolved nitrate concentrations in the lower Yellow River were 1.38 and 1.12 times higher before and during water and sediment regulation than after, because of excess reactive nitrogen elution from the beach by the water and sediment regulation. The nitrogen release risk was low in suspended particulate matter and surface sediments (ion exchangeable form nitrogen content was 0.007-0.033 mg center dot g- 1) but high in soil (average ion exchangeable form nitrogen content was 0.092 mg center dot g- 1). Leaching results indicated that nitrate concentration in the water was not significantly influenced by the reduction in suspended particulate matter or surface sediments. In contrast, in soil S-13 (ion exchangeable form nitrogen content was 0.371 mg center dot g- 1), the estimated leaching rate of nitrate averaged 14.74 %, and ion exchangeable form nitrogen accounted for 19.25 % of total nitrogen, with 76.56 % of ion exchangeable form nitrogen leached. Therefore, the water and sediment regulation elution and the continuous leaching of nitrogen from washland soils around the lower Yellow River notably increased the nitrogen concentration in the lower Yellow River.

Nitrogen (N) in suspended particulate matter (SPM) plays a vital role in estuarine and coastal ecosystems. However, the accumulation and migration processes of N in SPM and their effects on water quality evolution are still unclear. This study utilized three methods (gravity-setting, dry sieving, and wet sieving) to categorize the particle size of SPM in the Yellow River Estuary (YRE). Simulated tests and the field sampling of SPM in the YRE were conducted to examine N accumulation and migration patterns in SPM across different salinity levels, particle sizes and migration distance. Adsorption experiment was used to investigate the potential impact of N in SPM on water quality evolution. The results indicated that SPM could be effectively sorted into distinct particle size groups through gravity-setting, and fine-grained SPM contributed to accumulating N under low salinity. The SPM with the largest particle size at a salinity of 33 PSU presented the lowest TN concentration of 818.4 mg center dot kg- 1. In comparison, the SPM with the smallest D50 at a salinity of 0.48 PSU exhibited the highest TN (2438 mg center dot kg- 1). Microbial community analysis underscores the microbial-mediated mechanisms driving N dynamics in SPM. Cyanobacteria play a crucial role in N accumulation in fine-grained SPM, while salinity and N concentration significantly influenced the distribution of key bacterial phyla (e.g. Proteobacteria and Planctomycetota). Additionally, fine-grained SPM tends to suspend in the water column and are carried by river flow towards offshore, the sampling point located furthest from the YR mouth (N8) recorded the highest TN concentration of 1973 mg center dot kg- 1 in SPM. During the migration process, the release potential of N in SPM has significantly increased, thereby exacerbating the risk of N pollution and N/P ratio imbalance in seawater. This study presents a novel perspective on addressing N pollution and N/P ratio imbalance, highlighting the significance of intercepting fine particles for effective N management in estuarine and coastal zones.

Dissolved oxygen (DO) critically regulates biogeochemical processes in mariculture sediments, yet its integrated effects on sulfur-metal interactions during sediment aging remain poorly understood. This study investigated the migration and transformation of reduced inorganic sulfur (RIS) and heavy metals in mariculture sediments under varying DO levels. Lower DO accelerated the dominance of acid-volatile sulfide (AVS) within the reduced inorganic sulfur pool (AVS/RIS = 56.11

Water exchange is a key step in mariculture activities. However, the impact of water exchange frequency (WEF) on the environmental behavior of sulfur and heavy metals is not well understood. In this study, the migration and transformation of sulfur and heavy metals in mariculture sediments under different WEFs were investigated. The results indicated that high WEF would be unfavorable to overlying water quality, while increased acid volatile sulfur (AVS) in the sediments (11.13 μmol/g). High WEF accelerated the release of heavy metals from bottom sediments and their enrichment in the surface layer, leading to an increase in heavy metal content in the surface sediments, with Cd showing particularly significant changes (CV, ∼20%). Moreover, the WEF also had an obvious effect on the Cd fraction (CV>10%). The increase in acid-soluble Pb inhibited the conversion of AVS to chromium (II)-reducible sulfur (CRS) in the sediments, enhancing the sediment aging process. An appropriate frequency of water exchange (once every 5 days) could increase the abundance and diversity of bacteria and help to shape specific microorganisms. Changes in heavy metals in the surface sediments caused Firmicutes to become the most affected bacterial species by the WEF. The functional flora involved in the sulfur cycle were lesser affected by the WEF (CV, ∼5%), whereas those involved in the nitrogen cycle were more affected (CV >17%). The findings provide guidance for scientific mariculture.

The safe management of toxic metal-polluted dredging sediment (DS) is imperative owing to its potential secondary hazards. Herein, the co-pyrolysis product (DS@BC) of polluted DS was creatively applied to immobilize soil Cd and As to achieve DS resource utilization, and the efficiency, safety, and mechanism were investigated. The results revealed that the DS@BC was more effective at reducing soil Cd bioavailability than the DS was (58.9-73.2% vs. 21.8-27.4%), except for the dilution effect, whereas the opposite phenomenon occurred for soil As (25.5-35.7% vs. 35.7-42.8%). The DS@BC immobilization efficiency was dose-dependent for both Cd and As. Soil labile Cd and As were transformed to more stable fractions after DS@BC immobilization. DS@BC immobilization inhibited the transfer of soil Cd and As to Brassica chinensis L. and did not cause excessive accumulation of other toxic metals in the plants. The appropriate addition of the DS@BC (8%) sufficiently alleviated the oxidative stress response of the plants and enhanced their growth. These findings indicate that the DS@BC was safe and effective for soil Cd and As immobilization. DS@BC immobilization decreased the diversity and richness of the rhizosphere soil bacterial community because of the dilution effect. The DS@BC immobilized soil Cd and As via direct adsorption, and indirect increasing soil pH, and regulating the abundance of specific beneficial bacteria (e.g., Bacillus). Therefore, the use of co-pyrolyzed DS as a soil Cd and As immobilization material is a promising resource utilization method for DS. Notably, to verify the long-term effects and safety of DS@BC immobilization, field trials should be conducted to explore the effectiveness and risk of harmful metal release from DS@BC immobilization under real-world conditions.

Current sulfide removal techniques are generally associated with secondary pollution. In this work, Fe/MgO/Ni (II) system was constructed to remove sulfide from waters thoroughly by transforming it into stable pyrite (FeS2). The transformation could be finished quickly through the promotion of Ni2+ at all pH conditions, and the optimal Ni/Fe molar ratio was 1.0. The FeS2 could be formed in 360 min and the reaction was finished at 600 min when the initial concentration of sulfide and Ni2+ was 181.95 mg/L and 164.52 mg/L, respectively. The highest content of SO42- was merely 2.06 %, while the content of S2O32- /SO32- increased with reaction (56.99 %-67.21 %) in the whole process. The content of sulfide and Ni2+ in the solution were not detected after reaction. The mineralization process was not affected by sodium salt addition, however, it was greatly affected by calcium salt, where the ascensional range of S2O32-/SO32- and SO42- was 50.03 %-70.06 % and 9.84 %-14.76 %, respectively, and the content of sulfide on Fe/MgO was only 14.66 %. Higher temperature would produce more SO42- and H+. The rapid formation mechanism of FeS2 was mainly through Ni2+ substituting Fe in FeS to form Ni-doped FeS precursors that reacted with polysulfide and then promoted the nucleation of FeS2, in the meantime, the reaction to form S2O32-/SO32-, SO42-, Ni(OH)2 and H+ also were generated in this process. This study provides a new insight for the efficient treatment of sulfide containing wastewater.

Organic matter (OM) significantly impacts the environmental behavior of sulfur and heavy metals. In this study, the effects of OM on the migration and transformation of sulfur and heavy metals in mariculture sediments were investigated. The results indicated that baiting had a strong impact on the accumulation of acid volatile sulfur (AVS) (P < 0.05) and increased the environmental risk of sulfide in sediments. The addition of bait promoted the generation of chromium (II)-reducible sulfur (CRS); however, the resistance of AVS to CRS conversion increased with increasing bait addition. The addition of bait considerably influenced Cd accumulation. The acid-soluble fractions of Cr and Cu and the oxidizable fraction of Cd were primarily affected by the bait addition (coefficient of variation>15 %). An increase in the reducible fraction promoted the conversion of AVS to CRS, which reduced the degree of sediment aging. Higher OM levels reduced the diversity and abundance of the bacterial communities. The sulfate respiration functional microbiota was particularly affected by OM.

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The remediation of Cd-polluted sediment in coastal rivers is essential because of its potential hazards to river and marine ecosystems. Herein, a co-pyrolysis product of contaminated dredged sediment (S@BC) was innovatively applied to cap and immobilize Cd-contaminated sediment in coastal rivers in situ, and their remediation efficiencies, mechanisms, and microbial responses were explored based on a 360 d incubation experiment. The results showed that although S@BC immobilization and capping restrained sediment Cd release to the overlying water, S@BC capping presented a high inhibitory efficiency (66.0% vs. 95.3% at 360 d). Fraction analysis indicated that labile Cd was partially transformed to stable fraction after remediation, with decreases of 0.5%32.7% in the acid-soluble fraction and increases of 5.0%- 182.8% in the residual fraction. S@BC immobilization and capping had minor influences on the sediment bacterial community structure compared to the control. S@BC could directly adsorb sediment mobile Cd (precipitation and complexation) to inhibit Cd release and change sediment properties (e.g., pH and cation exchange capacity) to indirectly reduce Cd release. Particularly, S@BC capping also promoted Cd stabilization by enhancing the sediment sulfate reduction process. Comparatively, S@BC capping was a priority approach for Cd-polluted sediment remediation. This study provides new insights into the remediation of Cd-contaminated sediments in coastal rivers.

Antibiotics in the environmental waters pose long-term threat to ecological safety because of their persistent and potential toxic nature. FeS and FeS2 were proved to be efficient catalysts for the activation of peroxymonosulfate (PMS) and the generation of sulfate radical generation for refractory pollutant degradation. However, their performance for antibiotic degradation has not yet been comparatively and comprehensively investigated. Herein, the FeS/PMS and FeS2/PMS systems were developed to explore chloramphenicol (CAP) degradation under equal conditions. The results show that CAP was efficiently degraded in both two systems, with a removal efficiency exceeding 90 % within 120 min using 6 mM PMS and 0.6 g/L catalysts. Acceleration in degradation rate was observed in the FeS2/PMS system when the catalyst dosage ranged from 0.1 g/L to 1.0 g/L (constant PMS concentration) with a reaction rate constant (k(obs)) of 2.1-fold higher than that in the FeS/PMS system. However, the k(obs) were comparable with the PMS concentration range (constant catalyst dosage) in the two systems, suggesting that the catalysts were the rate-limiting step in CAP degradation process. The initial pH strongly affected CAP degradation in the FeS/PMS system but had little effect on that in the FeS2/PMS system. Surface Fe2+ played a dominant role in PMS activation, and S-2(2-)/S2- facilitated Fe2+ regeneration. Further, both FeS and FeS2 had stable activity for PMS activation during long-term use. This study proves the effectiveness of FeS and FeS2 for PMS activation for antibiotic degradation and differentiates their catalytic qualities, which will provide alternative heterogeneous catalysts for practical application.