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• Co 1.1 Mn 1.9 O 4 exhibited excellent activity to activate PAA for SMX degradation. • CH 3 C(O)OO● was evidenced as the dominant reactive oxidizing species. • Significant role of Mn in intensifying the activity of Co sites was revealed. • Co 1.1 Mn 1.9 O 4 /PAA process had great potential in high-salinity wastewater treatment. Activation of peracetic acid (PAA) to generate powerful oxidizing species has become a promising advanced oxidation processes (AOPs) in wastewater treatment, yet the development of low-cost and high-performance activators is still a primary challenge. Herein, a range of Co–Mn spinel oxides (Co 3-x Mn x O 4) with varying levels of Co and Mn were successfully elaborated, in which Co 1.1 Mn 1.9 O 4 exhibited remarkable performance in PAA activation, outperforming most reported heterogeneous catalysts. Extensive quenching experiments and electron spin resonance (ESR) analysis indicated that acetylperoxyl radical (CH 3 C(O)OO●) was the predominated oxidizing species responsible for sulfamethoxazole (SMX) degradation. Density functional theory (DFT) calculations revealed that doping with Mn not only promoted the electron transfer and accelerated reduction of Co(III) to Co(II), but also lowered the energy barrier for PAA activation. Moreover, the prominent chemisorption and activation of PAA with Co 1.1 Mn 1.9 O 4 was also benefitted from the significant role of Mn in optimizing the distribution of bonding and antibonding states on Co 3d orbitals. Unexpectedly, high levels of Cl−greatly facilitated SMX degradation due to the mass production of HOCl from the chain reactions of various radicals with Cl−. This work provides new insights into bimetallic activation of PAA, and the knowledge obtained will further advance the application of PAA-based AOPs. [Display omitted] [ABSTRACT FROM AUTHOR]

• nCuO exhibited the highest reactivity in PAA activation among nMOPs. • High reactivity of Cu(I) in PAA activation was unveiled. • A new scavenging experiment was developed to distinguish CH 3 C(O)OO●. • Co-existing H 2 O 2 played a significant role in Cu(II)/Cu(I) conversion. • The nCuO/PAA process is promising in real wastewater decontamination. Peracetic acid (PAA)-based advanced oxidation processes (AOPs) has attracted increasing attentions towards contaminant degradation in the wastewater treatment. Herein, we report the efficient activation of PAA by nano-CuO (nCuO/PAA) to degrade carbamazepine (CBZ) for the first time. Rapid degradation of CBZ was observed in the nCuO/PAA system at neutral initial pH. A new scavenging experiment with Mn2+ as a specific scavenger was developed to distinguish the dominant role of CH 3 C(O)OO● for CBZ degradation in the nCuO/PAA process. The oxidation of CBZ by CH 3 C(O)OO● was verified to proceed via the electrons transfer, and the acute and chronic toxicity of the transformation products was significantly reduced. The efficient activation of PAA by nCuO was found to be realized through continuous conversion of Cu(II) to Cu(I), which was significantly boosted by co-existing H 2 O 2. The nCuO/PAA process was slightly affected by the water matrices, and maintained high efficiency in real water samples. The findings obtained in this study provide new insights into the catalytic formation of CH 3 C(O)OO● from PAA and facilitate the development and application of PAA-based AOPs in wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

• Human manure (HM) is an ideal waste biomass for the production of P fertilizer. • Hydrothermal carbonation was used to recover high-bioavailable P from HM directly. • C and P were preserved in the derived P-rich hydrochars (PHCs) well. • The derived PHCs has a promising application potential. Phosphorus (P) recovery from human manure (HM) is critical for food production security. For the first time, a one-step hydrothermal carbonation (HTC) treatment of HM was proposed in this study for the targeted high-bioavailable P recovery from P-rich hydrochars (PHCs) for direct soil application. Furthermore, the mechanism for the transformation of P speciation in the derived PHCs was also studied at the molecular level. A high portion of P (80.1∼89.3%) was retained in the solid phase after HTC treatment (120∼240°C) due to high metal contents. The decomposition of organophosphorus (OP) into high-bioavailable orthophosphate (Ortho-P) was accelerated when the HTC temperature was increased, reaching ∼97.1% at 210°C. In addition, due to the high content of Ca (40.45±2.37 g/kg) in HM, the HTC process promoted the conversion of low-bioavailable non-apatite inorganic (NAIP) into high-bioavailable apatite inorganic P (AP). In pot experiments with pea seedling growth, the application of newly obtained PHCs significantly promoted plant growth, including average wet/dry weight and plant height. Producing 1 ton of PHCs (210°C) with the same effective P content as agricultural-type calcium superphosphate could result in a net return of $58.69. More importantly, this pathway for P recovery is predicted to meet ∼38% of the current agricultural demand. [Display omitted] [ABSTRACT FROM AUTHOR]

• PAA was effective in inactivating AR E. coli and preventing their regrowth. • PAA could induce antibiotic resistant E. coli into viable but nonculturable state. • Amino acids containing thiol, thioether and imidazole groups are inactivation sites. • PAA was poorly reactive with plasmid strands and bases. • PAA-treated plasmid remained high-efficient transformation functionality. The occurrence of a viable but nonculturable (VBNC) state in antibiotic-resistant E. coli (AR E. coli) and inefficient degradation of their antibiotic resistance genes (ARGs) may cause potential health risks during disinfection. Peracetic acid (PAA) is an alternative disinfectant for replacing chlorine-based oxidants in wastewater treatment, and the potential of PAA to induce a VBNC state in AR E. coli and to remove the transformation functionality of ARGs were investigated for the first time. Results show that PAA exhibits excellent performance in inactivating AR E. coli (over 7.0-logs) and persistently inhibiting its regeneration. After PAA disinfection, insignificant changes in the ratio of living to dead cells (∼4%) and the level of cell metabolism, indicating that AR E. coli were induced into VBNC states. Unexpectedly, PAA was found to induce AR E. coli into VBNC state by destroying the proteins containing reactive amino acids at thiol, thioether and imidazole groups, rather than the result of membrane damage, oxidative stress, lipid destruction and DNA disruption in the conventional disinfection processes. Moreover, the result of poor reactivity between PAA and plasmid strands and bases confirmed that PAA hardly reduced the abundance of ARGs and damaged the plasmid's integrity. Transformation assays and real environment validation indicated that PAA-treated AR E. coli could release large abundance of naked ARGs with high-efficiency transformation functionality (∼5.4 × 10–4 - ∼8.3 × 10–6) into the environment. This study has significant environmental implications for assessing the transmission of antimicrobial resistance during PAA disinfection. [Display omitted] [ABSTRACT FROM AUTHOR]