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[Display omitted] • It was firstly demonstrated that the synergistic activation of PMS by MoS 2 @PANI and Cu(II). • High removal rate of sulfathiazole (≥85 %) achieved within a wide range of pH (3–10) in Cu(II)/MoS 2 @PANI/PMS. • H O ∙ , Cu(Ⅲ) and 1 O 2 were generated in Cu(II)/MoS 2 @PANI/PMS, while SO 4 ∙ - was negligible. • Compared with Fe(II), Cu(II) improved reusability and applicability of MoS 2 @PANI in activation of PMS. • The absorption of Cu(II) on MoS 2 @PANI improved the stability of MoS 2 @PANI. This paper synergistically combined MoS 2 @PANI (coating MoS 2 on polyaniline (PANI)) with Cu(II) to obtain effective activation of PMS in a wide range of pH (3–10). The removal rate of sulfathiazole (ST) in Cu(II)/MoS 2 @PANI/PMS (98 %) in 60 min was higher than in Cu(II)/PMS (50 %) and MoS 2 @PANI/PMS (70 %). Besides, the PMS consumption rate was 100 % within 30 min in Cu(II)/MoS 2 @PANI/PMS. Different concentrations of Cl - and HCO 3 - promoted the degradation of ST in varying degrees. And NO 3 - slightly inhibited the degradation of ST (removal rate more than 84 %). Notably, Cu(II)/MoS 2 @PANI/PMS could remove more than 80 % ST in different water bodies. The special structure of MoS 2 @PANI increased many activity sites of Mo(IV) to promote the cycle of Cu(II)/Cu(I) for activating PMS which generated H O ∙ , Cu(III) and 1 O 2. Twenty-seven degradation intermediates were identified and four possible degradation paths of ST were proposed. Moreover, Cu(II)/MoS 2 @PANI/PMS possessed a good non-selectivity for various organic pollutants. After three consecutive cycles, the removal rate still retained more than 90 % in Cu(II)/MoS 2 @PANI/PMS system. Compared with Fe(II), MoS 2 @PANI was more stable in Cu(II)/MoS 2 @PANI/PMS. The synergy of Cu and Mo broke the limitation of PMS activation under environmental aquatic conditions. Given that Cu(II) widely existed in wastewater, the new research strategy increased the application scope for homogeneous PMS activation with inherently Cu(II) in wastewater in environmental remediation. [ABSTRACT FROM AUTHOR]

Al 2 O 3 -based CoFe 2 O 4 (CoFe 2 O 4 /Al 2 O 3 ) as a catalyst was prepared to activate peroxymonosulfate (PMS) for degradation of sulfachloropyridazine (SCP). In general, the catalytic performance of CoFe 2 O 4 /Al 2 O 3 in activation PMS was demonstrated more effective than CoFe 2 O 4 . Several influence factors were inspected, including scavengers, PMS concentration, pH, anions, nature organic matter (NOM) and temperature. The oxidation of SCP fitted a pseudo-first-order kinetics model and was efficient with the pH from 5.00 to 8.00. The influence of scavengers demonstrated that SO 4 - · played a more significant role than HO · in the oxidation process. The removal was strongly inhibited by adding NOM or HCO 3 - , and almost unaffected by adding NO 3 - , while chloride could enhance the degradation in the system. The increasing temperature greatly promoted the degradation of SCP. After four recycles, CoFe 2 O 4 /Al 2 O 3 still showed preferable catalytic performance with 97.6% removal rate of SCP. Furthermore, the degradation mechanism was explored based on the XPS results. In the composit of CoFe 2 O 4 /Al 2 O 3 , Al 2 O 3 had no additional catalytic performance but just as a matrix base. [ABSTRACT FROM AUTHOR]

[Display omitted] • The catalyst with optimized Cu/Mg molar ratio rapidly activated PMS to remove TAP. • MgO wrapped CuO nanoparticles in the catalyst and limited copper ion leaching. • MgO promoted the formation of Cu-OH complex and redox cycle of Cu+-Cu2+-Cu+. • Activation mechanism of PMS and degradation pathways of TAP were proposed. Copper-base catalysts with high load content of CuO were commonly utilized to activate peroxymonosulfate (PMS) for removal of contaminants but limited catalytic efficiency and increased risk of copper ion leaching restricted their use. In this paper, Cu-Mg mixed metal oxides with highly dispersed minute quantities of CuO were successfully prepared by one-pot synthesis for efficiently activating PMS to remove thiamphenicol (TAP), which was economical and environmentally friendly. The catalytic activities of catalysts with different molar ratios of Cu and Mg for PMS and their characteristics were evaluated, illustrating the optimal molar ratio of Cu and Mg (1:15, named CuMg-MMO) in the catalyst. For the CuMg-MMO catalyst, MgO widely dispersed and wrapped CuO nanoparticles, minimized the copper ion leaching and promoted the generation of Cu-OH complex and non-radical species. In the CuMg-MMO/PMS system, the influence factors for TAP degradation were analyzed, including different systems, catalyst dosages, PMS concentrations, temperatures, initial pH values, TAP concentrations, anions (N O 3 - , H C O 3 - , C l - , H P O 4 2 - and H 2 P O 4 -) and natural organic matter (NOM) concentrations. Under the optimal conditions (i.e., [catalyst]: 75 mg/L, [PMS]: 0.3 mM, temperature: 30 °C and initial pH: 6.5), TAP removal efficiency obtained by this system was 99.9%. S O 4 · - , · O 2 - and 1O 2 played more important roles than H O · in TAP degradation. Four successive repeated experiments indicated that CuMg-MMO possessed good reusability and stability. PMS decomposition, mineralization of TAP, the activation mechanism of PMS and possible degradation pathways of TAP were analyzed. [ABSTRACT FROM AUTHOR]

• AA can remarkably improved DEET removal by Fe(III)/PS process. • ·SO 4 − and ·OH played a major role in DEET removal. • The existence of Fe(IV) in Fe(III)/PS/AA system was successfully identified. • Introducing AA into Fe(III)/PS system performed better than other reducing agents. • The reduction and chelation ability of AA both played crucial roles. The introduction of ascorbic acid (AA) into Fe(III)/PS system exhibited extremely high activity on the removal of N,N-diethyl- meta -toluamide (DEET) and other pollutants. The removal efficiency of DEET within 30 min reached 90.13%, its dynamic curve obeyed second-order kinetic model and the k obs was calculated to be 0.150 L·mg−1·min−1. Compared with other reducing agents, AA was tested to be the most suitable. The optimal dosages of Fe(III), PS and AA were tested to be 0.1, 1.0 and 0.5 mM, respectively. Furthermore, the introduction of AA extended the working pH to 2.5–9.3. Common anions posed different degrees of inhibition on DEET degradation at relatively high concentration, while a small dosage of HCO 3 − (<1 mM) abnormally exerted a positive role. In terms of reaction mechanism, scavenger experiment and EPR observation illustrated that ·OH and ·SO 4 − dominated DEET degradation, yet slight Fe(Ⅳ) was also found during the reaction, which indicated that Fe(Ⅳ) may also contribute to DEET removal. Different from the rapid consumption of Fe(II) in Fe(II)/PS system, Fe(II) in Fe(III)/PS/AA system entered a dynamic equilibrium state in the later stage of the reaction, which can decompose PS to form ·SO 4 − continuously. Furthermore, the reduction and chelation ability of AA both functioned a key role. According to the degradation intermediates identified by LC-MS analysis, the degradation pathways of DEET could be divided into two directions, which covered opening benzene ring and removing side chain. [ABSTRACT FROM AUTHOR]