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[Display omitted] • A novel E H 2 O 2 -MB-O 3 process was developed for antibiotics removal from wastewater. • More efficient CIP removal and mineralization were achieved in E H 2 O 2 -MB-O 3 process. • •OH oxidation was enhanced in E H 2 O 2 -MB-O 3 and contributed to CIP removal mainly. • Pyridone and piperazine ring in CIP molecule could be attacked by •OH more easily. Microbubble ozonation combined with electro-generated H 2 O 2 process (E H 2 O 2 -MB-O 3) was applied to degrade ciprofloxacin (CIP) as a typical antibiotic in wastewater in this study. The results showed that the performance of CIP degradation and mineralization in E H 2 O 2 -MB-O 3 process was more efficient than other related processes. Microbubble ozonation and electro-generated H 2 O 2 showed obvious synergistic effect on enhanced CIP removal in E H 2 O 2 -MB-O 3 process. The O 3 dosage, applied current and initial pH in E H 2 O 2 -MB-O 3 process were optimized as 12.5 mg/min, 50 mA and 7.0 (uncontrolled). Under the optimal conditions, CIP could be degraded completely within 60 min and the TOC removal efficiency of 28.85% could be achieved within 90 min in E H 2 O 2 -MB-O 3 process. The corresponding ozone utilization efficiency was close to 100%. More efficient ROS generation was observed in E H 2 O 2 -MB-O 3 process, especially •OH, compared with other related processes. The contribution rates of •OH, 1O 2 , O 3 and O 2.- to CIP removal were determined as 66.79%, 23.57%, 6.67% and 2.98% in E H 2 O 2 -MB-O 3 process, respectively. The electro-generated H 2 O 2 was clarified to contribute to not CIP removal but ROS generation. Three CIP degradation pathways were proposed according to identified degradation intermediates, which indicated that pyridone structure of quinoline and piperazine ring in CIP molecule could be destroyed more easily than benzene ring of quinoline, and the hydroxylation seemed to prevail in these CIP degradation pathways due to •OH electrophilic addition reaction probably. The removal of other antibiotics in E H 2 O 2 -MB-O 3 process also depended on not ozone direct oxidation but •OH oxidation mainly. [ABSTRACT FROM AUTHOR]

Considering the complexity of traditional cobalt phosphide (Co 2 P) loaded biochar synthesis research on a simple and efficient synthesis method has practical significance. In this study, after phosphoric acid activation, Neosinocalamus affinis biochar (NAB) and nanoplate Co 3 O 4 quickly formed a Co 2 P-NAB composite material with high Co 2 P crystallinity and was uniformly dispersed on the surface of NAB in a microwave reactor. Co 2 P-NAB has an excellent catalytic degradation effect in the activation of peroxymonosulfate (PMS) to degrade tetracycline (TC). The optimal TC degradation efficiency was achieved with the addition of 50 mg L−1 TC concentration, 0.2 g L−1 catalysts, 0.406 mM PMS and pH = 6.02. In addition, according to the pseudo-first-order reaction rate constant calculation, the composite of Co 2 P-NAB and PMS the synergy efficiency is 81.55 %. Compared with Co 2 P-NAB (10.83 %) and PMS (7.62 %) alone, the Co 2 P-NAB/PMS system has a significant promotion effect on the degradation of TC molecules. Additionally, the Co 2 P-NAB/PMS system had a TC mineralization rate of 68 % in 30 min. Furthermore, after a series of characterization, detection and analysis, and influencing factor experiments, we proposed a potential mechanism for the Co 2 P–NAB/PMS reaction system to degrade TC and found that singlet oxygen (1O 2) plays an essential role in the non-radical degradation process. Finally, according to the liquid chromatography-mass spectrometry (LC-MS) detection of TC degradation intermediates, a possible degradation route was proposed. Therefore, this work uses microwave technology to present a novel and simple synthesis method for transition metal phosphides, which provides potential application value for the treatment of actual wastewater with heterogeneous catalysts. Co 2 P functionalized neosinocalamus affinis biochar for pH-universal degradation of antibiotic tetracycline. [Display omitted] • Microwave assisted synthesis for preparing Co 2 P decorated biochar material. • The unique porous Co 2 P-NAB material can efficiently degrade tetracycline in water. • Co 2 P-NAB/PMS degrades antibiotic tetracycline in a broad pH ranging from 3 to 11. • Non-radical singlet oxygen acts as the main active sites in Co 2 P-NAB/PMS system. [ABSTRACT FROM AUTHOR]

• A series of honeycombed catalysts were successfully constructed via facile in situ synthetic method. • Au@C-TiO 2-X exhibited superior catalytic activity for the deep mineralization of AR3R under visible light. • The introduction of C and Au species promote the generation of reactive oxygen species. • The superior photocatalytic activity of Au@C-TiO 2-X is attributed to the synergistic effect of •O 2 − and •OH. The mineralization of organic pollutants under visible light is challenging, limiting the practical application of photocatalytic technology in wastewater treatment. To achieve the efficient mineralization of Acid red 3R (AR3R), a series of honeycombed catalysts (TiO 2 , C-TiO 2-X , Au@TiO 2 and Au@C-TiO 2-X) were prepared via a facile in situ synthetic method and characterized by XRD, TEM, BET, XPS and DRS, respectively. The introduction of C and Au species promote the simultaneous generation of •O 2 − and •OH over Au@C-TiO 2-X under visible light radiation. The Au@C-TiO 2-X catalyst showed superior performance for the deep mineralization of AR3R, affording a TOC removal rate larger than 90 % within 240 min under visible light (> 420 nm). The photocatalytic degradation mechanism of AR3R is proposed according to UV–vis and in situ DRIFTS analysis. The superior photocatalytic activity of Au@C-TiO 2-X is attributed to the synergistic effect of •O 2 − and •OH owing to C doping and Au deposition. [ABSTRACT FROM AUTHOR]