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Alkaline substances could activate peroxymonosulfate (PMS) for the removal of organic pollutants, but relatively high alkali consumption is generally required, which can cause too high pH of the solution after the reaction and lead to secondary pollution. Within this study, PMS activated by a relatively low dosage of Ca(OH)2 (1 mM) exhibited excellent efficiency in the removal of bisphenol S (BPS). The pH of the solution declined to almost neutral (pH = 8.2) during the reaction period and conformed to the direct emission standards (pH = 6–9). In a typical case, BPS was completely degraded within 240 min and followed the kinetics of pseudo-first-order. The degradation efficiency of BPS depended on the operating parameters, such as the Ca(OH)2, PMS and BPS dosages, initial solution pH, reaction temperature, co-existing anions, humic acid (HA), and water matrices. Quenching experiments were performed to verify that singlet oxygen (1O2) and superoxide radicals (O2˙−) were the predominant ROS. Degradation of BPS has been significantly accelerated as the temperature increased. Furthermore, degradation of BPS could be maintained at a high level across a broad range of pH values (5.3–11.15). The SO4−, NO3− did not significantly impact the degradation of BPS, however, both HCO3− and HA inhibited oxidation of BPS by the Ca(OH)2/PMS system, and Cl− had a dual-edged sword effect on BPS degradation. In addition, based on the 4 identified intermediates, 3 pathways of BPS degradation were proposed. The degradation of BPS was lower in domestic wastewater compared to other naturals waters and ultrapure; nevertheless, up to 75.86%, 77.94% and 81.48% of BPS was degraded in domestic wastewater, Yaohu Lake water and Poyang Lake water, respectively. Finally, phenolic chemicals and antibiotics, including bisphenol A, norfloxacin, lomefloxacin hydrochloride, and sulfadiazine could also be efficiently removed via the Ca(OH)2/PMS system.

Peroxymonosulfate (PMS) was successfully adopted to remove organic pollutants in water, but it was rarely applied to soil remediation. Sulfathiazole (STZ) is a widely used sulfonamide antibiotic, while its residues have negative impacts on soil. To the best of our knowledge, this is the first attempt to apply PMS for the treatment of STZ-contaminated soil. The results showed that 4 mM PMS can degrade 96.54% of STZ in the soil within 60 min. Quenching and probe experiments revealed that singlet oxygen rather than hydroxyl radical and sulfate radical was the predominant reactive oxygen species responsible for STZ removal. The presence of Cl

Alkaline substances could activate peroxymonosulfate (PMS) for the removal of organic pollutants, but relatively high alkali consumption is generally required, which can cause too high pH of the solution after the reaction and lead to secondary pollution. Within this study, PMS activated by a relatively low dosage of Ca(OH)

Homogeneous Cu

In this study, a favorable CO32−/PMS system for efficient degradation of organic contaminants (acid orange 7 (AO7), acetaminophen, para-aminobenzoic acid, phenol, methylene orange, methylene blue) in water was firstly reported. Under optimal conditions, the decolorization ration of AO7 was 100% within 40 min. Data fitting showed that the AO7 decolorization could be described by the pseudo-first-order kinetics, and the rates constant values ranging from 0.0006 to 0.2297 min−1 depending on the operating parameters (initial PMS, CO32−, AO7 concentrations). Radical scavenging studies revealed that superoxide anion radical (O2 −) and singlet oxygen (1O2) rather than sulfate (SO4 −) nor hydroxyl (HO ) were the dominant oxidants might be responsible for AO7 degradation. The presence of NO3−, HPO42− and low concentration of Cl−, NO2−, HCO3−, H2PO4−, HA had no significantly effect on the decolorization of AO7. Adding a higher Cl− concentration displayed favorable effects on the removal efficiencies of AO7, but adding a higher NO2−, HCO3−, H2PO4− and HA concentration apparently inhibited this process. The decolorization of AO7 was lower in wastewater in comparison to other natural waters and ultrapure water, which was probably due to the presence of higher concentration of colloids in wastewater. Nevertheless, up to 94.8%, 97.0% and 85.1% of AO7 were degraded from the filtrate, permeate, and retentate phases of wastewater within 60 min, respectively. Consequently, CO32−/PMS would be promising for removal methodology for AO7 in wastewater containing considerable colloids. Finally, three intermediates were identified and degradation pathways of AO7 were proposed.