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Advanced oxidation processes (AOPs) stand out as promising solutions for wastewater purification. An integration of a photothermal effect in AOPs will bring about a transformative impact on the processes. This innovative approach will boost treatment efficiency and overcome the limitations of the conventional ones. In this review, we thoroughly investigate the progress of applying a photothermal effect on various AOPs technologies for robust wastewater treatment. Our discussion encompasses the origin of the photothermal effect, elucidation of its working principles, and a summary of strategies for engineering the photothermal effect to catalytically remove contaminants. Furthermore, we delve into the diverse applications of photothermal effect in wastewater treatment technologies, spanning photocatalysis, peroxymonosulfate activation, and the Fenton reaction. Finally, we identify some challenges and outline future prospectives for the implementation of photothermal wastewater treatment. This review is anticipated to rejuvenate conventional AOPs, offering more clean, sustainable, and efficient technologies for wastewater treatment. [ABSTRACT FROM AUTHOR]

Copper and zinc composite oxides (Cu2O/ZnO) were synthesized by an impregnation-reduction-air oxidation method. A series of Cu2O/ZnO/rGO ternary composites were prepared by coupling with graphene oxide (GO) with different mass fractions in a solvothermal reaction system. The microscopic morphology, crystal structure, and optical characteristics of the photocatalysts were characterized. The degradation of p-Nitrophenol (PNP) and polyacrylamide (PAM) by photocatalytic materials under simulated solar irradiation were studied, and the degradation kinetics were also investigated. The results showed that cubic Cu2O was modified by ZnO nanorods and distributed on rGO nanosheets. The ternary Cu2O/ZnO/rGO nanocomposites have stronger simulated solar absorption ability and higher photodegradation efficiency than pure ZnO and binary Cu2O/ZnO nanocomposites. When the amount of Cu2O/ZnO/rGO-10 was 0.3 g L−1, the degradation rate of 10 mg L−1 PNP reached 98% at 90 min and 99.6% of 100 mg L−1 PAM at 30 min. The photocatalytic degradation processes of PNP and PAM all followed the pseudo-first-order kinetic model. Free radical trapping experiments showed that superoxide radicals were the main active substances to improve photocatalytic efficiency. In addition, after four recycles, the catalytic efficiency of Cu2O/ZnO/rGO-10 was still over 90%. It showed that Cu2O/ZnO/rGO-10 was a promising catalyst for wastewater treatment because of its good photostability and reusability. [ABSTRACT FROM AUTHOR]

Peroxydisulfate (PDS) based advanced oxidation processes (AOPs) are widely used for the degradation of pharmaceutical and personal care products (PPCP) in wastewater treatment. In this study, a Fe-doped g-C 3 N 5 (Fe@g-C 3 N 5) was synthesized as a photocatalyst for catalyzing the PDS-based AOPs to degrade tetracycline hydrochloride (TH) at pH 3 and Naproxen (NPX) at pH 7. The photocatalytic performance of Fe@g-C 3 N 5 was 19% and 67% higher than g-C 3 N 5 and g-C 3 N 4 for degradation of TH at pH 3, respectively, while it was 21% and 35% at pH 7. The Fe:N ratio in Fe@g-C 3 N 5 , was calculated as 1:3.79, indicating that the doped Fe atom formed a FeN 4 structure with an adjacent two-layer graphite structure of g-C 3 N 5 , which improved the charge separation capacity of g-C 3 N 5 and act as a new reaction center that can efficiently combine and catalyze the PDS to radicals. Although the intrinsic photo-degradation performance is weak, the photocatalytic performance of Fe@g-C 3 N 5 has great room for the improvement and application in wastewater treatment. [Display omitted] • Generation of sulfate radicals by photocatalysis was improved with Fe@g-C 3 N 5. • The FeN 4 coordination structure was confirmed in Fe@g-C 3 N 5. • Fe atom coordinated with N atoms were in the two adjacent layers of g-C 3 N 5. • The combination site of PDS changed from N atom in g-C 3 N 5 to Fe atom in Fe@g-C 3 N 5. [ABSTRACT FROM AUTHOR]

Denitrifying sulfide removal (DSR) process comprising both heterotrophic and autotrophic denitrifiers can simultaneously convert nitrate, sulfide, and acetate into nitrogen gas, elemental sulfur (S), and carbon dioxide, respectively. Sulfide- and nitrate-laden wastewaters at 2-35 g/L NaCl were treated by DSR process. A C/N ratio of 3:1 was proposed to maintain high S conversion rate. The granular sludge with a compact structure and smooth outer surface was formed. The microbial communities of DSR consortium via high-throughput sequencing method suggested that salinity shifts the predominating heterotrophic denitrifiers at <10 g/L NaCl to autotrophic denitrifiers at >10 g/L NaCl. [ABSTRACT FROM AUTHOR]

Electro-Fenton reaction mechanism by the porous fiber electrodes of NZVIF-800 for degradation and sterilization. [Display omitted] • Nano-zero-valent iron based electrostatic spinning fiber electrode was fabricated. • Electrode showed great electro-Fenton activity for secnidazole and real wastewater. • Decomposition process of secnidazole and organics in real wastewater was revealed. • Electrode exhibited strong sterilization ability for the actual wastewater matrix. In this study, a novel metal–organic framework (MOF) derived fiber electrode (NZVIF-800) was successfully fabricated by a novel electrostatic spinning and pyrolysis procedure. The NZVIF-800 electrode exhibited great catalytic activity in a heterogeneous electro-Fenton (EF) system for organic degradation, in which the secnidazole (SCZ) was completely degraded within 60 min with excellent stability (no significant change after eight cycles). Importantly, the NZVIF-800 electrode was also highly effective for decontaminating actual pharmaceutical wastewater, in which the TOC and COD removal reached 38% and 47%, respectively, after 4 h EF reaction. Based on experimental analysis, microstructure characterization, and theoretical calculations, the detailed reaction mechanism of the NZVIF-800 electrode was revealed. The impressive EF performance was mainly attributed to the in situ generation of active nano-zero-valent iron (NZVI) derived from the MOF pyrolysis and the confinement effect of the encased carbon layer that could effectively inhibit the loss and inactivation of Fe active sites. The degradation pathways of organic pollutants in simulated and real wastewater were proposed in detail. Significantly, the EF system with NZVIF-800 electrode exhibited strong sterilization ability for the wastewater matrix as evidenced by the colony condition, OD 600 values, and Illumina MiSeq sequencing platform analysis (up to 95% sterilization efficiency within 4 h), expanding its application scope for actual wastewater treatment. [ABSTRACT FROM AUTHOR]

The oily wastewater composed of complicated organic pollutants and bacteria showed a huge threat on the environment and humans. Currently, the membrane used to treat oily wastewater have the problems of cumbersome preparation, weak adhesion and metal leaching, and membrane pollution is also the focus of urgent problems. In this study, the metal-free chlorine-sulphur double-doped graphitic carbon nitride (Cl/S-g-C 3 N 4) photocatalyst was incorporated into polyacrylonitrile (PAN) nanofibrous membrane via an electrospun method. The resultant porous nanofibrous membrane possessed the superior superhydrophilicity and superoleophobicity under water, ensuring a high separation efficiency (>98.0%) for various oil-in-water emulsions. Specially, the membrane achieved a superior self-cleaning property after visible light irradiation for crude oil/water mixture and actual oily wastewater with FRR up to 95%, which was related to the enhanced light absorption ability and the effective electron hole separation ability of Cl/S-g-C 3 N 4. Moreover, the porous structure increased the possibility of contact between contaminants/bacteria and reactive species, beneficial to the photodegradation and antibacterial properties, achieving extremely high resistance to contamination. Overall, the multifunctionality of the porous anti-fouling nanofibrous membrane exhibited a huge potential in practical oily wastewater treatment. [Display omitted] • A multifunctional oil-water separation membrane was prepared. • Nanofibrous membranes exhibited an excellent antifouling performance. • Photocatalytic degradation ability was assessed by intermittent and continuous experiments. • Nanofiber membrane exhibited strong self-cleaning and antibacterial ability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cl/S-CN is synthesized by original hydrothermal self-repairing method. • COP system display greatly enhanced degradation performance of organic wastewaters. • The generation of ROS-rich region promotes the degradation performance. Catalytic ozone oxidation synergistic photocatalysis (COP) can effectively overcome the shortcomings of incomplete mineralization and strong pH dependence of O 3 and slow reaction rate of photocatalytic. Cl, S double-doped carbon nitride nanotube unit (Cl/S-CN) with the ability of catalyzing O 3 and visible light photocatalysis was synthesized by hydrothermal self-repairing method to improve the applicability of the COP system in actual organic wastewater. Characterization and density functional theory (DFT) calculations found that Cl/S-CN has a stable and ordered nanotube (tube diameter: 56 nm) arrangement, a good energy band structure, and excellent e- delivery efficiency. It can generate reactive oxygen species (ROS)-rich region in the unit to promote the ROS chain cycle reaction, thereby generating more numbers and types of (non–)free radicals to participate in the degradation of organic pollution. For tetracycline (100 mg/L), the degradation rate in O 3 /vis/Cl/S-CN system was 90.1% at 10 min, and the degradation rate of TOC was 78% at 30 min. For P-nitrophenol (20 mg/L), the degradation rate was 91.6% at 20 min, and the degradation rate of TOC was 66% at 30 min. The COD degradation rates of influent water, secondary effluent water and oilfield produced water in COP system at 30 min were 70.5%, 83.4% and 76.5%, respectively. Cl/S-CN can catalyze the production of high activity ROS-rich region in COP system, effectively promote the production of ·OH, 1O 2 and other active substances, and improve the applicability of COP system in actual organic wastewater. [ABSTRACT FROM AUTHOR]