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A series of composite photocatalysts LaFeO3/CdS‐x (LFO/CS‐x, x=10–50 wt%) were prepared by a simple sol‐gel and solvothermal two‐step method for photo‐Fenton degradation of levofloxacin (LVF). The removal rate of LVF by LFO/CS‐40 reached 97.3 % within 100 min, showing excellent photocatalytic activity compared with LaFeO3 and CdS. The prepared composites were characterized and analyzed by XRD, FT‐IR, DRS, SEM, HRTEM, XPS, photoelectrochemical analysis and other techniques. Mechanistic investigations show that the heterojunction structure, can promote the separation and migration of photogenerated electron‐hole pairs, and the photogenerated charges can induce the generation of various active species under the synergistic effect of H2O2, and then efficiently degrade pollutants. Additionally, the effects of different parameters on the photo‐Fenton degradation were explored, and the good stability of composites is proved by cycling tests. The LFO/CS‐40 composite photocatalyst designed in this work has potential application prospects in the green and efficient treatment of antibiotic wastewater. [ABSTRACT FROM AUTHOR]

Melanoidins, the dark-color recalcitrant Maillard reaction by-products in thermal hydrolyzed sludge (THS), cause significant adverse effects on wastewater treatment. This study aimed to develop an efficient adsorption method for recovering melanoidins from THS by macroporous resin. The adsorptive characteristics of six macroporous resins (XAD761, XAD8, XAD16HP, FPX66, HPD-600 and IRA958Cl) showed that XAD761, not yet reported for melanoidins extraction, was the most appropriate with the highest recovery ratio. The adsorption kinetics followed pseudo-second-order model, and the adsorption process was confirmed to be physical, spontaneous, and exothermic, without changing the structure of the adsorbed melanoidins. In the dynamic adsorption, the breakthrough point increased with a decreasing flow rate. After five consecutive regeneration cycles, XAD761 resin maintained stable adsorption efficiency and thus had a good potential for reuse. Furthermore, the physicochemical properties of the extracted THS melanoidins were compared with model melanoidins to lay the foundation for their management, in terms of morphology, molecular weight (MW), and spectrophotometric properties. These results demonstrate that XAD761 resin extraction is a promising sustainable method for practical application in the recovery of melanoidins from THS. [Display omitted] • XAD761 was identified for the first time the resin to extract melanoidins from THS. • XAD761 adsorption was physical, spontaneous and exothermic without structure change. • The breakthrough point increased with a decreasing flow rate in dynamic adsorption. • XAD761 remained stable adsorption efficiency during consecutive regeneration cycles. • Morphology, molecular weight and spectrophotometry of THS melanoidins were studied. [ABSTRACT FROM AUTHOR]

Ultrafiltration membranes have shown remarkable potential in the purification of textile printing and dyeing wastewater. However, ultrafiltration membranes have some disadvantages in wastewater treatment, such as membrane fouling and trade-off effect. Hence, a novel polysulfone (PSF)-reduced graphene oxide (rGO)-zinc oxide (ZnO) composite conductive ultrafiltration membrane was prepared via the simple and green method. The combination of conductive ultrafiltration membrane and external electric field could treat dye wastewater. The conductive rGO/ZnO/PSF membranes have high water flux (296 L m−2 h−1 Bar−1) and favorable removal rates (>90%) for Congo Red (CR), Methyl Orange (MO), and Methylene Blue (MB). Besides, rGO/ZnO/PSF membrane also showed excellent antifouling ability, which had a flux recovery rate of 93% after filtration of bovine serum albumin (BSA) under applied electric field. Due to the electrocatalytic cleaning, rGO/ZnO/PSF membrane exhibited a 90% flux recovery after filtering the dye. The rGO/ZnO/PSF membrane has good separation efficiency, electrocatalytic stability, and fouling resistance, and can effectively solve the purification of textile printing and dyeing. Under the synergistic effect of filtration system and external electric field, ultrafiltration membrane has achieved excellent selectivity for small molecular dyes. [Display omitted] • A simple method for preparing conductive rGO/ZnO/PSF membrane was developed. • rGO/ZnO/PSF membrane exhibited ultra-high water flux and high dye removal rate. • The dye removal rate of rGO/ZnO/PSF membrane remained above 90% after 5 h. • The antifouling property of rGO/ZnO/PSF membrane was improved by electro-cleaning. [ABSTRACT FROM AUTHOR]

[Display omitted] • PAN-ZnO NFM was fabricated with electrostatic spinning and magnetron sputtering. • PAN-ZnO NFM exhibited ultra-high water flux (1016 L m−2 h−1 Bar−1) and high dye removal rate. • PAN-ZnO NFM showed excellent electrocatalytic stability. • PAN-ZnO NFM was easy to clean with electricity. Nanofiber membranes (NFMs) prepared with electrostatic spinning have attracted more and more attention in wastewater treatment owing to its unique advantages of high porosity and large specific surface area. However, the low removal rate of small molecular weight dyes and membrane fouling are the main obstacles for its large-scale application. Therefore, new polyacrylonitrile (PAN)-ZnO NFM was prepared simply and efficiently combined with electrostatic spinning technology and magnetron sputtering. Under the action of electrocatalysis, PAN-ZnO NFM exhibited not only high removal rate (>95%) for Congo red (CR), rhodamine B (RhB), sunset yellow (YS), methyl orange (MO) and methylene blue (MB), but also excellent water flux (1016 L m−2 h−1 Bar−1). Moreover, the electrocatalytic stability investigation of PAN-ZnO NFM showed that the membrane still maintained an excellent dye removal rate (>90%) after 10 h of continuous electrocatalytic filtration. Apart from, PAN-ZnO NFM also displayed excellent mechanical properties (252 MPa of Young's modulus) and antifouling ability. The permeate flux recovery rate of more than 90% after electrocatalytic cleaning for 5 min. Due to its excellent properties in dye removal rate, water flux, electrocatalytic stability, and antifouling, PAN-ZnO NFM exhibited an excellent application prospect in textile wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • PAN-ZnO NFM was fabricated with electrostatic spinning and magnetron sputtering. • PAN-ZnO NFM exhibited ultra-high water flux (1016 L m−2 h−1 Bar−1) and high dye removal rate. • PAN-ZnO NFM showed excellent electrocatalytic stability. • PAN-ZnO NFM was easy to clean with electricity. Nanofiber membranes (NFMs) prepared with electrostatic spinning have attracted more and more attention in wastewater treatment owing to its unique advantages of high porosity and large specific surface area. However, the low removal rate of small molecular weight dyes and membrane fouling are the main obstacles for its large-scale application. Therefore, new polyacrylonitrile (PAN)-ZnO NFM was prepared simply and efficiently combined with electrostatic spinning technology and magnetron sputtering. Under the action of electrocatalysis, PAN-ZnO NFM exhibited not only high removal rate (>95%) for Congo red (CR), rhodamine B (RhB), sunset yellow (YS), methyl orange (MO) and methylene blue (MB), but also excellent water flux (1016 L m−2 h−1 Bar−1). Moreover, the electrocatalytic stability investigation of PAN-ZnO NFM showed that the membrane still maintained an excellent dye removal rate (>90%) after 10 h of continuous electrocatalytic filtration. Apart from, PAN-ZnO NFM also displayed excellent mechanical properties (252 MPa of Young's modulus) and antifouling ability. The permeate flux recovery rate of more than 90% after electrocatalytic cleaning for 5 min. Due to its excellent properties in dye removal rate, water flux, electrocatalytic stability, and antifouling, PAN-ZnO NFM exhibited an excellent application prospect in textile wastewater treatment. [ABSTRACT FROM AUTHOR]