Singlet oxygen-dominated peroxymonosulfate activation by layered crednerite for organic pollutants degradation in high salinity wastewater

Distribution characteristics and migration trends of hexabromocyclododecanes between seawater-sediment system in different seasons of fishing grounds along the Yellow sea and East China sea coasts

Pollutants in the ecological environment of fishery seawater are harmful to the survival and reproduction of aquatic organisms. Hexabromocyclododecanes (HBCDs) were 42.9% detected within ND-48.89 ng/L in 177 seawater samples and 30.7% within ND-1.07 ng/g dw in 88 sediment samples of the fisheries in the Yellow Sea and East China Sea, respectively. γ-HBCD accounted for 65% of seawater and 89% of sediment samples. HBCDs in seawater in winter (ND-48.89 ng/L) were significantly higher than in summer (ND-4.99 ng/L), possibly because the re-suspension caused by winds and waves could re-migrate HBCDs from the sediment to the seawater in winter. However, seasonal differences of HBCDs in sediment were not significant. The fugacities indicated HBCDs' migrating trend from seawater to sediment due to their hydrophobic nature. There is almost no terrestrial input of HBCDs from the Yangtze and Yellow Rivers, and currently used fishery materials in marine may compose long-lasting sources of HBCDs.

Efficient carbamazepine degradation with Fe3+ doped 1T/2H hybrid molybdenum disulfide as peroxymonosulfate activator under high salinity wastewater

Drawing on the robust activation activity and affinity that transition metal ions and MoS₂ exhibit towards peroxymonosulfate (PMS), 1T/2H hybrid molybdenum disulfide doped with Fe³⁺ (Fe³⁺/N-MoS₂) was synthesized to activate PMS for the treatment of organic wastewater. The ultrathin sheet morphology and 1T/2H hybrid nature of Fe³⁺/N-MoS₂ were confirmed by characterization. The (Fe³⁺/N-MoS₂ + PMS) system demonstrated excellent performance in the degradation of carbamazepine (CBZ) above 90% within 10 min even under high salinity conditions. By electron paramagnetic resonance and active species scavenging experiments, it was inferred that SO₄^•─ palyed a dominant role in the treatment process. The strong synergistic interactions between 1T/2H MoS₂ and Fe³⁺ efficiently promoted PMS activation and generated active species. Additionally, the (Fe³⁺/N-MoS₂ + PMS) system was found to be capable of high activity for CBZ removal in high salinity natural water, and Fe³⁺/N-MoS₂ exhibited high stability during recycle tests. This new strategy of Fe³⁺ doped 1T/2H hybrid MoS₂ for more efficient PMS activation provides valuable insights for the removal of pollutants from high salinity wastewater.