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• Antibiotics are ubiquitous due to their extensive production and consumption. • AOPs are effective to degrade antibiotics in water and wastewater. • The recent advance in antibiotics degradation by AOPs was analyzed and summarized. • Fenton, ozonation, photocatalytic, electrochemical and ionizing radiation were introduced. • Concluding remarks were given and their future perspectives and challenges were discussed. Antibiotics are becoming emerging contaminants due to their extensive production and consumption, which have caused hazards to the ecological environment and human health. Various techniques have been studied to remove antibiotics from water and wastewater, including biological, physical and chemical methods. Among them, advanced oxidation processes (AOPs) have received increasing attention due to their fast reaction rate and strong oxidation capability, which are effective for the degradation of antibiotics in aquatic environments. In this review paper, a variety of AOPs, such as Fenton or Fenton-like reaction, ozonation or catalytic ozonation, photocatalytic oxidation, electrochemical oxidation, and ionizing radiation were briefly introduced, including their principles, characteristics, main influencing factors and applications. The current applications of AOPs for the degradation of antibiotics in water and wastewater were analyzed and summarized, the concluding remarks were given and their future perspectives and challenges were discussed. [ABSTRACT FROM AUTHOR]

In this study, the performance of activated sludge derived granular activated carbon (SGAC) was investigated for ciprofloxacin (CPX) removal from synthetic and simulated wastewaters in a fixed-bed adsorption column operated in continuous mode. The adsorbent was synthesized using chemical activation using ZnCl 2 as activating agent. Its surface area and pore volume were found comparable to that of the commercial granular activated carbon (CGAC). The maximum saturation adsorption capacities for CPX were ~16 mg/g and ~14 mg/g, respectively, with SGAC column under identical operating conditions (CPX concentration = 50 mg/L, bed height = 4 cm and wastewater flow rate = 1.5 mL/min) for synthetic and simulated wastewaters. The presence of other organics reduced CPX adsorption capacity of SGAC. The breakthrough curve data for both wastewaters could be adequately fit in Thomas and Yoon-Nelson kinetic models. The addition of H 2 O 2 in wastewater showed no considerable improvement in CPX removal. However, H 2 O 2 oxidation of spent adsorbent exhibited better results compared to thermal treatment for adsorbent regeneration. The results showed that sewage sludge can be recycled as an efficient adsorbent for the removal of recalcitrant organic pollutants from wastewater. Image 1 • CPX removal by activated sludge derived AC was studied in a fixed bed column. • The effect of particle size and matrix components on CPX removal was investigated. • In comparison to adsorption, Fenton-like oxidation slightly improved CPX removal. • The breakthrough curve data could be adequately fit in Thomas and Yoon-Nelson models. • Peroxide oxidation of waste derived AC was better than thermal regeneration process. [ABSTRACT FROM AUTHOR]

The study of sonolytic degradation of metazachlor (MZC), which was activated by either oxygen or insoluble Fe(III) was performed. Herbicide MZC was selected as a target compound due to its wide use in agriculture. The results indicated the positive effect of oxygen used as undoubtedly the most harmless H-scavenger promoting the penetration of HO from the gaseous phase of the cavitation bubble into the liquid phase and the interphase region. Another approach in activation of sonolysis was the application of Fe 2 O 3 used as a source of iron in order to utilize H 2 O 2 generated as a result of combination of HO∙-s in the interphase region of the cavitation bubble. The present study revealed the synergistic effect of the combination of sonolysis and Fenton-like oxidation. The pseudo-first order rate constant of MZC sonolytic degradation increased from 1.11 × 10−2 min-1 for conventional sonolysis to 1.79 × 10−2 and 2.88 × 10−2 min-1 for O 2 -saturated and Fe 2 O 3 -added solutions, respectively. The application of ultrasound demonstrated the amplifying effect on the detachment of Fe(III) from insoluble ferric oxyhydroxide (Fe 2 O 3 ·nH 2 O) in acidic environment into the aqueous solution, thereby improving the oxidation of organic compounds. MZC followed two degradation pathways, which are the cleavage of the aliphatic sites of MZC with the initial hydroxylation reactions and oxidation of pyrazole group. [ABSTRACT FROM AUTHOR]

In this work, we assessed the potential of combining Fenton´s reagent and biological oxidation for removing the imidazolium-based ionic liquid 1-Ethyl-3-methylimidazolium chloride (EmimCl). Fenton-like oxidation was conducted at variable H 2 O 2 doses from 20 to 100% the stoichiometric value as calculated from the theoretical chemical oxygen demand (COD). The stoichiometric H 2 O 2 dose afforded Total Organic Carbon (TOC) conversion and COD removal of 50 and 62%, respectively. Identifying the reaction by-products formed at low hydrogen peroxide doses allowed a plausible pathway for EmimCl oxidation to be proposed. The effluents from Fenton-like oxidation at substoichiometric H 2 O 2 doses were less ecotoxic and more biodegradable than was the parent ionic liquid. The effluent from Fenton-like oxidation with the 60% H 2 O 2 dose (TOC conversion ≅ 41%, COD removal ≅ 31%) was subsequently subjected to an effective biological treatment that allowed complete removal of the starting compound, increased its ecotoxicity to a low-moderate level and rendered it acceptably biodegradable. Biological oxidation was performed in 8-h and 12-h cycles in a sequencing batch reactor. Combining Fenton and biological oxidation of EmimCl afforded TOC conversion and COD removal of around 90%., (Copyright © 2018 Elsevier B.V. All rights reserved.)