This study employed H₂S in an ethanol-phase as a sulfidation reagent to synthesize sulfidated nanoscale zero-valent iron (S-nZVI-H₂S-Ethanol) through a liquid-phase chemical reduction approach. A systematic investigation was conducted to examine the effects of sulfidation time duration on the material's surface characteristics, electrochemical properties, hydrogen suppression capability, and dechlorination performance. The results revealed that prolonged sulfidation treatment led to the formation of flake-like iron-sulfur compounds(FeSx) on the particle surfaces, accompanied by a significant increase in specific surface area. XPS analysis demonstrated a non-monotonic relationship between sulfidation time and surface composition: Fe-S content initially increased before decreasing, while Fe-O content exhibited the inverse trend. Electrochemical characterization indentified the S-nZVI-H₂S-Ethanol(S12h) exhibited optimal performance, with the lowest charge transfer impedance and the lowest corrosion potential (-0.923V), suggesting enhanced electron transfer efficiency and reductive capacity. Hydrogen evolution experiments confirmed that sulfidation effectively suppressed the hydrogen evolution reaction, with the hydrogen generation rate decreasing initially before stabilizing with extended treatment time. In TCE dechlorination experiments, both nZVI and S-nZVI-H₂S-Ethanol followed pseudo-first-order kinetics, demonstrating markedly higher apparent rate constants (kb: 1.4/h, 0.81/h, and 0.48/h for S2h, S12h, and S24h, respectively) compared to pristine nZVI (0.025/h). The degradation product distribution of trichloroethylene revealed that the degradation pathways were governed by competing β-elimination and hydrogenation reactions, yielding primarily acetylene, ethylene, ethane, and long-chain hydrocarbons (C₃-C₆). These results collectively demonstrated that ethanol-phase H₂S sulfidation significantly enhances nZVI's degradation performance. The comprehensive examination of S-nZVI-H₂S-Ethanol's surface properties and dechlorination efficiency across varying sulfidation durations provides crucial insights for optimizing material design in environmental remediation applications.

This study systematically explores the performance and mechanisms of zirconium-based gel coagulant (ZXC) synthesized by the sol-gel method in fluoride removal. Through optimizing parameters, examining the impacts of coexisting matrix, and analyzing physicochemical properties, we found that ZXC achieved the best fluoride removal at pH 4.0. ZXC outperformed traditional coagulants like polyaluminum chloride (PAC), polyferric sulfate (PFS), and titanium-based coagulants (TXC), effectively reducing fluoride to below 1.0mg/L with low residual metal concentrations. The fluoride removal by ZXC involves a "concentration-dependent multi-mechanism synergy process," primarily via ligand exchange at low concentrations, and through direct coordination, co-precipitation, and condensation at higher concentrations. Field tests demonstrate that ZXC can reduce fluoride levels in contaminated groundwater, electroplating wastewater, and photovoltaic wastewater to below 1.5mg/L, meeting the first-tier discharge standards. This work offers an efficient and practical solution for industrial fluoride wastewater and high-fluoride groundwater treatment.

The development of photothermal materials derived from coal slime, a solid waste from coal mining, offers a promising approach for the resource utilization of both coal waste and highly mineralized mine water. Coal slime was processed into coal-based carbon material (MC) through calcination and pickling processes. The MC exhibited excellent light absorption (~95.0% in the 200~2500nm) and photothermal performance, with the surface temperature reaching 55.1℃ within 180s of illumination. A spherical evaporator with high-salinity resistance and self-suspension was prepared by incorporating sodium alginate into MC and crosslinking it with calcium chloride, using sodium bicarbonate as a pore-forming agent and polyvinyl alcohol as a foam stabilizer, via the dropwise method. The optimized composite (SA_2/1-MC₂) showed strong photothermal performance, achieving evaporation rates of 0.97kg/(m²·h) for 20.0wt% NaCl solution and 0.99kg/(m²·h) for reverse osmosis concentrated mine water, with stable operation over 10h. These results demonstrate that SA_2/1-MC₂ is an effective material for treating highly mineralized mine water.

In this study, short-term batch experiment was used to investigate the mechanism of thiocyanate (0~500mg/L) addition on the anammox granular sludge system. The results showed that as the concentration of thiocyanate influent increased, nitrogen removal efficiency of Anammox decreased significantly, and the total nitrogen removal efficiency decreased from 88.6% in the control group to 43.3% (500mg/L thiocyanate); The anammox activity (SAA) also showed a rapid decreasing trend. The non-competitive inhibition model determined the 50% inhibitory concentration (IC₅₀) of thiocyanate on Anammox to be 209.5mg/L. The EPS secreted by Anammox cells increased after the addition of thiocyanate. The PN/PS increased with the rise of the concentration of thiocyanate. The relative abundance of Candidatus Brocadia was significantly decreased after the addition of thiocyanate, while the relative abundance of Thiobacillus increased sharply, and The abundance of microbial functional metabolism pathways appeared to be reduced to different degrees. The research results can provide a theoretical basis for the application of Anammox engineering in treating nitrogenous wastewater containing thiocyanate.

In this study, the UV activated periodate (PI, IO₄^-) system (UV/PI) was investigated to degrade PhACs in urine (UV(10W low pressure, peak at 254nm), PI (5mmol/L)), the results demonstrated that the degradation rate of 12 selected Pharmaceutically active compounds (PhACs) exceeded 60% at 10min; based on this, the influence of urine matrix on PhACs degradation was further studied. In fresh urine matrices, urea and citrate reacted with the radicals, inhibiting the degradation of PhACs, with the rate constant k_i decreasing by about 0.0083~0.0129s^-1 compared to the UV/PI system. Meanwhile, Cl^- reacted with the radicals to form lower reactive chlorine species (RCS), which negatively affected the degradation efficiency, with the k_i decreasing by about 0.0015~0.0056s^-1. In hydrolyzed urine matrices, urea and citrate were hydrolyzed into NH₃ and HCO₃^-. Then, NH₃ and HCO₃^- reacted with the radicals to produce reactive nitrogen species (RNS) and CO₃·^-, which further reacted with PhACs. UV/PI system exhibited significant structural selectivity for the degradation of PhACs.

An AnMBR-PN/A system was developed for methylamine wastewater treatment. At optimal HRTs (AnMBR:8h, PN/A:9h), it achieved >95% COD and >86% TN removal, with effluent <5mg/L NH₄⁺-N and <15mg/L TN (meeting Class 1A standards). Net energy potential reached 0.72 with partial recovery, while energy-generating gases provided economic benefits. Versus A²/O, this system reduces operational costs and demonstrates dual advantages in energy conservation and emission reduction.

In this paper, a novel iron-based nanocomposite lignin hydrogel (FeS@LH) was synthesized and applied to the activation of perdisulfate (PDS). Through the characterization of the material, it is found that the unique three-dimensional (3D) structure of the lignin hydrogel is helpful to the dispersion of sulfide nano-zero-valent iron particles (FeS particles) and increase the leakage site of FeS. This three-dimensional structure not only provides more attachment sites for FeS, PDS and pollutants, but also accelerates the electron transfer between FeS and PDS, thus promoting the degradation of pollutants. The experimental results show that FeS@LH has excellent performance in PDS activation. Under the condition of 0.1g/L catalyst and 1mmol/L PDS, 10mg/L IMI (100mL) can be completely degraded in 120minutes. Quenching experiments and electron spin resonance (ESR) spectra show that SO₄·^- and OH· are the main active species for IMI degradation in FeS@LH/PDS system. In addition, FeS@LH can effectively activate PDS to degrade IMI in the presence of inorganic anions and natural organic matter (HA). The degradation products of IMI were identified by liquid chromatography-mass spectrometry (UPLC-MS-MS) system, and two possible degradation pathways were proposed. The toxicity prediction results show that IMI can eventually be converted into a non-toxic product. FeS@LH was able to maintain a certain degradation efficiency after three cycles of testing, while exhibiting low metal leaching characteristics. Study results provide new ideas for the development of efficient degradation of pesticide pollutants.

This study utilizes ascorbic acid under hydrothermal conditions to composite ferric oxide (Fe₃O₄) and molybdenum disulfide (MoS₂), preparing Fe@C-MoS₂ with enhanced electron transfer for catalyzing the degradation of atrazine (ATZ) by peroxymonosulfate (PMS). Under the conditions of an ATZ concentration of 5mg/L, a catalyst dosage of 0.2g/L, and a PMS concentration of 1mmol/L, the removal rate of ATZ reached 84.6% after 35 minutes of reaction. Electrochemical experiments and XPS characterization demonstrated that the excellent catalytic performance of Fe@C-MoS₂ is attributed to the carbon source-induced generation of mixed-phase MoS₂, which effectively improves the conductivity of the catalyst and promotes rapid electron transfer. Additionally, through bio-toxicity tests using locally grown cauliflower as the study subject, the feasibility of using the solution degraded by the Fe@C-MoS₂/PMS system as agricultural irrigation water was evaluated. The results indicate that the post-degradation solution showed negligible effects on both the survival rate of cauliflower seedlings and their growth parameters when compared with conventional water sources.

Given high concentrations of chemical oxygen demand (COD), ammonium nitrogen (NH₄⁺-N), suspended solids (SS), and poor biodegradability of concentrated swine farm wastewater, a combined treatment process of "pretreatment-biochemical treatment-advanced treatment" was employed in this study, specifically designed as "solid-liquid separation → anaerobic fermentation → A/O → MBR." By comparing influent characteristics and pollutant removal efficiency between summer and winter, the energy consumption and greenhouse gas (GHG) emission profiles of the system were systematically analyzed. The average effluent COD and TN in the summer were significantly lower than those in the winter (711.21mg/L and 61.78mg/L, respectively), indicating that low temperature significantly inhibit the treatment efficiency. The A/O unit dominated energy usage, with a consumption of 7.65 (kW·h)/m³, accounting for 56.48% of total energy demand. The annual GHG emissions totaled 1364.41t CO₂-eq, with an emission intensity of 15.53kg CO₂-eq/m³. The emission intensities per unit COD and TN removed were 1.33kg CO₂-eq/kg COD_removed and 10.89kg CO₂-eq/kg TN_removed, respectively. Further analysis revealed that external electricity consumption contributed to 72.98% of total GHG emission, followed by nitrous oxide (N₂O) release (25.99%). Through the regulation of seasonal process parameters, the development of multi-mode operation strategies, and the integration of online monitoring technologies, the precise control of the treatment process is optimized to achieve the goals of energy saving, consumption reduction, and low-carbon operation.

On the basis of investigating the effect of fluoranthene (Flu) on the anaerobic co-digestion of sludge and kitchen waste, the mechanism on anaerobic co-digestion was comprehensively analysed. The results demonstrated that anaerobic methanogenesis was enhanced within the appropriate concentration of Flu (≤50mg/kg TSS). The maximum methane yield of the anaerobic co-digestion system [30.7mL/(gVSS·d)] was achieved at Flu concentration of 50mg/kg TSS, which was 1.61times that of the control group. Mechanistic studies showed that hydrolysis, acidification and acetoclastic methanogenesis were promoted by Flu, as evidenced by the increased activities of acetate kinase (ACK, 1.30-fold) and coenzyme F420 (1.43-fold) relative to the control. Microbial community structure demonstrated that not only Prevotella and Trichococcus, involved in organic matter hydrolysis and acidification, were selectively enriched in the Flu group, but also the relative abundance of the acetoclastic methanogen Methanosarcina was increased. Metagenomics further revealed that the relative abundances of functional genes associated with glycolysis (HK, pfk and PK), volatile fatty acid production (por, ackA and buk) and acetoclastic methanogenesis (pta, ACSS1_2, cdhD and cdhE) were up-regulated, favouring methanogenesis.