Antibiotic Wastewater Research Articles

Construction of ligand functionalized MIL-101(Fe)-R and mechanism of efficient removal of chlortetracycline hydrochloride: Experiment and DFT calculation

Functionalization of ligands is an effective strategy to enhance the adsorption performance of adsorbents. In this study, MIL-101(Fe)-R (R = -H, –OH, –NH2, and –NO2) was selected as a platform for systematically studying the impact of functionalization on the adsorption behavior of chlortetracycline (CTC). A series of characterizations were conducted on the prepared MIL-101(Fe)-R to clarify the influence of organic linkers on the microscopic morphology, pore structure, and surface functionality of the adsorbents. Additionally, the effects of different functional groups on the adsorption behavior of MIL-101(Fe)-R were compared to screen for MOFs with high efficiency in removing CTC. Experimental results showed that the maximum adsorption capacities (qm) of MIL-101(Fe), MIL-101(Fe)–NH2, MIL-101(Fe)–OH, and MIL-101(Fe)–NO2 were 418.980 mg/g, 559.854 mg/g, 187.387 mg/g, and 154.131 mg/g, respectively. Among them, MIL-101(Fe)–NH2 exhibited a higher mass transfer rate (reaching equilibrium in 15 min). Based on apparent adsorption behavior, adsorption kinetics, isotherm and thermodynamic studies, as well as FTIR and XPS characterizations before and after adsorption, the performance modulation mechanism of MIL-101(Fe)-R in CTC adsorption was discussed in detail. Combined with density functional theory (DFT) calculations, the host–guest interaction controlling the adsorption behavior was understood at the molecular level, demonstrating the optimal binding sites of the adsorbents. This study provides guidance for the design of efficient MOF adsorbents for antibiotic wastewater treatment.

Activating peroxymonosulfate with Fe-doped biochar for efficient removal of tetracycline: Dual action of reactive oxygen species and electron transfer

If pharmaceutical wastewater is not managed effectively, the presence of residual antibiotics will result in significant environmental contamination. In addition, inadequate utilization of agricultural waste represents a squandering of resources. The objective of this research was to assess the efficacy of iron-doped biochar (Fe-BC) derived from peanut shells in degrading high concentrations of Tetracycline (TC) wastewater through activated peroxymonosulfate. Fe-BC demonstrated significant efficacy, achieving a removal efficiency of 87.5% for TC within 60 min without the need to adjust the initial pH (20 mg/L TC, 2 mM PMS, 0.5 g/L catalyst). The degradation mechanism of TC in this system involved a dual action, namely Reactive Oxygen Species (ROS) and electron transfer. The primary active sites were the Fe species, which facilitated the generation of SO4•-, •OH, O2•-, and 1O2. The presence of Fe species and the C=C structure in the Fe-BC catalyst support the electron transfer. Degradation pathways were elucidated through the identification of intermediate products and calculation of the Fukui index. The Toxicity Estimator Software Tool (T.E.S.T.) suggested that the intermediates exhibited lower levels of toxicity. Furthermore, the system exhibited exceptional capabilities in real water and circulation experiments, offering significant economic advantages. This investigation provides an efficient strategy for resource recycling and the treatment of high-concentration antibiotic wastewater.

Rapid degradation of high-concentration antibiotic via heterogeneous photocatalysis coupling Fenton-like oxidation with MIL-53(Fe) under visible light irradiation

The photocatalytic technology based on Metal-Organic Frameworks (MOFs) has shown promising applications in the field of antibiotic pollution control. However, it still faces challenges in efficiently removing high-concentration antibiotic wastewater. A typical Fe-containing MOF, MIL-53(Fe), was successfully synthesized and demonstrated efficient photocatalytic activity under visible light irradiation for high-concentrations of tetracycline hydrochloride (TCH). However, the bare MIL-53(Fe) exhibited unsatisfactory photocatalytic performance. To overcome the low degradation efficiency resulting from the rapid recombination of light-induced electron-hole pairs, H2O2 was introduced as an external electron acceptor to establish a synergistic Fenton-like system to couple with the photocatalysis process. The results showed that in the MIL-53(Fe)/H2O2/Vis system, 99% of 1 g/L TCH was degraded within 80 min, while the degradation efficiency of the MIL-53(Fe)/Vis process was only 4.89% under identical conditions. The degradation mechanism of the coupling system was performed by radical scavenging experiments and Electron Spin Resonance characterization. The results indicated that ·OH was the dominant radical in the coupled reaction, and ·O2- and h+ also played a role in this system. The significant improvement in TCH degradation efficiency during the coupling process was attributed to the following three factors: (1) In the coupling reaction process, photo-generated electrons can stimulate H2O2 to form ·OH radicals, inhibiting the recombination of photo-generated electrons and holes, improving the efficiency of the photocatalytic reaction. (2) FeIII in MIL-53(Fe) can be excited by photo-generated electrons and converted to FeII, which then stimulates H2O2 to form ·OH radicals. (3) FeIII in MIL-53(Fe) can convert with FeII, stimulate H2O2 to form ·OH radicals, and participate in the degradation reaction. In addition, the reusability and stability of the MIL-53(Fe) photocatalyst in the coupled system, as well as the impact of operational parameters, were systematically studied. This work demonstrates a feasible strategy for environmental remediation by enhancing the efficiency of MIL-53(Fe) in photocatalytic Fenton-like systems, thereby providing a viable approach for the treatment of high-concentration antibiotic wastewater.

Gas-liquid-soild triphasic continuous flow microreactor for improving homogeneous distribution of solid composites in heterogeneous photocatalytic degradation progress

The homogeneous distribution of solid composites in continuous flow photocatalytic progress is difficult due to the settle and clog in capillary. To overcome this challenge, a gas–liquid-soild triphasic continuous flow photoreactor was designed and used for heterogeneous photocatalytic degradation of antibiotics wastewater. In this work, take Bi2WO6 as photocatalyst, photocatalytic degradation of ofloxacin wastewater was studied systematically under different operational parameters and flow characteristics. The photocatalytic degradation performance of flow photoreactor was superior to batch counterpart, especially in later stage of reaction. The apparent reaction rate constants (k) of flow photoreactor was about 1.6 times that of batch counterpart. The gas–liquid mass transfer coefficient of flow photoreactor was more than 25 times that of batch photoreactor. Moreover, the influence mechanism of gas fraction, flow rate and tube diameter on photocatalytic degradation performance was investigated under various continuous flow conditions. Higher gas fraction, faster flow rate and smaller tube diameter were beneficial to improve photocatalytic degradation performance due to the enhancement of irradiation transmission and intensification of mass transfer. Therefore, the results of this work provided a guideline for the application of gas–liquid-soild triphasic continuous flow photocatalytic degradation technology in the future.

Enhancing photocatalytic performance of Ni-Ti bimetallic metal-organic frameworks for tetracycline degradation under visible light irradiation

Antibiotic wastewater poses a significant threat to the global environment and human health. In this work, Ni-Ti bimetallic Metal-Organic Frameworks (NT-MOF) were synthesized as effective photocatalysts to remove tetracycline (TC) from water under visible light irradiation. The photocatalysts underwent characterization using techniques such as Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), N2 adsorption-desorption, and X-Ray Photoelectron Spectroscopy (XPS). Photocatalytic tests were conducted under visible light conditions (λ>420 nm). The enhanced performance is mainly due to the presence of Ni in NT-MOF changing the shape and structure of the samples, reducing electron-hole recombination, thus promoting the charge separation process. These findings have significant implications for the development of efficient and sustainable methods for the removal of TC from wastewater.

Design of magnetically separable double Z-scheme Ag3PO4/Fe3O4/MoS2 heterojunction with enhanced photocatalytic degradation of antibiotics under visible light irradiation

Photocatalysis is a promising technology in treating antibiotic wastewater. However, the rapid recombination of photogenerated electron-hole pairs and the loss of photocatalysts make its practical application challenging. To address these issues, a double Z-scheme heterojunction of magnetically separable Ag3PO4/Fe3O4/MoS2 photocatalyst is designed and applied for the photocatalytic degradation of tetracycline hydrochloride (TCH). The degradation efficiency of TCH by Ag3PO4/Fe3O4/MoS2 can achieve 99.0 % within 7.5 min under visible light irradiation, which is still above 91.3 % after 7 cycles. The excellent photocatalytic performance is attributed to the enhanced carrier life by constructing the double Z-scheme heterostructure in Ag3PO4/Fe3O4/MoS2. Mechanistic study indicates that •O2−, •OH, and h+ radicals are generated during the photocatalytic degradation. Combining experimental and theoretical calculations, two main degradation pathways are proposed, and the toxicity of the degradation system is significantly reduced. This study provides fresh insights into the photocatalytic degradation of refractory antibiotics by constructing magnetically separable Ag3PO4/Fe3O4/MoS2 heterojunction.

Construction and regulation of high active sites in montmorillonite composite catalyst for the removal of ofloxacin via persulfate activation

In this study, ionic liquids (ILs) were used as organic modifiers by introducing montmorillonite nanolayers containing potential C and N active sites between the montmorillonite nanolayers. Organically modified montmorillonite (ILs-Mt-p) was further prepared by high-temperature pyrolysis under N2 and used for the removal of ofloxacin (OFL) by activated peroxymonosulfate (PMS). Combined with XPS and other characterization analyses, it was found that the catalyst materials prepared from different organic modifiers had similar surface functional groups and graphitized structures, but contained differences in the types and numbers of C and N active sites. The catalyst (3CPC-Mt-p) obtained after pyrolysis of montmorillonite modified with cetylpyridinium chloride (CPC) had optimal catalytic performance, in which graphitic C, graphitic N, and carbonyl group (CO) could synergistically promote the activation of PMS by electron transfer, and 77.3 % of OFL could be removed within 60 min. The effects of OFL concentration, initial pH, and anions on the effects of OFL removal by the 3CPC-Mt-p/PMS system were further investigated. Satisfactory degradation results were obtained over a wide pH range. Cl− promoted the system to degrade OFL, while the presence of SO42−, H2PO4− and HA showed some inhibition, but overall the 3CPC-Mt-p catalysts had a strong anti-interference ability, showing good application prospects. The quenching experiments and EPR tests showed that O2−- and 1O2 in the 3CPC-Mt-p/PMS system were the main reactive oxygen species for the degradation of OFL, and •OH was also involved in the reaction. This study provides ideas for the construction and modulation of active sites in mineral materials such as montmorillonite and broadens the application of montmorillonite composite catalysts in advanced oxidation processes for the treatment of antibiotic wastewater.

MIL-88A(Fe)/g-C3N4 composite and its catalytic membrane for tetracycline removal via peroxydisulfate activation: Performance, mechanism and toxicity evaluation

Heterogeneous catalyst/persulfate advanced oxidation process has been widely used in antibiotic wastewater treatment. As-designed MIL-88A(Fe)/g-C3N4 composite catalyst firstly activated peroxydisulfate (PDS) to degrade tetracycline (TC) in this work. Activating PDS by MIL-88A(Fe)/g-C3N4 has a higher efficiency and rate toward TC degradation compared with MIL-88A(Fe) and g-C3N4. After 60 min, the optimal MIL-88A(Fe)/g-C3N4-5 activated PDS to degrade about 80% of TC in water. The existence of g-C3N4 increases the specific surface area and active Fe2+ content of MIL-88(Fe), promotes PDS adsorption and utilization, thus showing an excellent catalytic performance for PDS activation. MIL-88A(Fe)/g-C3N4 activated PDS oxidation process synergistically removed TC by free radicals (O2•−, •OH and SO4•−) with non-free radicals (1O2), and the effect of some important operating factors on TC removal, the TC degradation pathways and toxicity of TC intermediates were analyzed. Moreover, the MIL-88A(Fe)/g-C3N4-5 powdered catalyst was designed into a catalytic membrane, which could remove 96% of TC in a short time (<10 min). The cycle tests confirm that powdered MIL-88A(Fe)/g-C3N4 composite catalyst and its catalytic membrane have a good recyclability and stability, demonstrating that this catalyst possesses a practical application potential in the treatment of TC polluted wastewater.

Facile synthesis of nano CeO2/sepiolite composite as visible-light-driven photocatalyst for rapid tetracycline removal

A novel CeO2/sepiolite (CeO2/SEP) composite with sepiolite as the support of CeO2 was successfully prepared using a simple ammonia precipitation method for the photocatalytic degradation of tetracycline (TC) by loading CeO2 nanoparticles on sepiolite. The analytical results showed that CeO2/SEP had good crystallization, and CeO2 nanoparticles were deposited on the surface of fibrous sepiolite. The composite photocatalyst with 50 % CeO2 loading presented the highest tetracycline degradation efficiency (92.7 %), and the reaction rate constant was 4.88 times greater than that of pure CeO2. In addition, quenching experiments showed that the main reactive active species included photogenerated holes (h+) and superoxide radical anions(O2·-).Furthermore, the enhanced photodegradation mechanisms and the possible degradation pathways of TC were also systematically discussed. The investigating results show that the enhanced photocatalytic performance was mainly due to the uniform attachment of CeO2 with smaller particle size on the surface of sepiolite, which increased the specific surface area of the photocatalyst and promoted the redox cycle of Ce3+/Ce4+ to generate more reactive free radicals. It can be concluded that this study offers a new potential option for efficient photodegradation of antibiotics in wastewater based on the visible-light-driven mineral based photocatalyst.

Fabrication and characterizations of a novel Ce modified PbO2 electrode with Ti4O7-rGO as the middle layer for degradation of ceftazidime

Developing stable and high-performance electrodes for effective removal of antibiotics from wastewater remains a significant challenge. Herein, a novel Ce-doped PbO2 electrode with Ti4O7-reduced graphene oxide as the middle layer (Ti/Ti4O7-rGO/Ce-PbO2) was fabricated through drop-coating and electrodeposition for the electrocatalytic degradation of ceftazidime (CAZ). The prepared Ti/Ti4O7-rGO/Ce-PbO2 electrode exhibited more active sites, higher oxygen evolution potential, and stronger ability for hydroxyl radical (•OH) generation. In the degradation experiments, approximately 100 % of CAZ (30 mg L−1) was degraded by the Ti/Ti4O7-rGO/Ce-PbO2 electrode at 40 mA cm−2 in 0.1 M Na2SO4 solution within 90 min. The quenching test and EPR analysis indicated that the •OH played a pivotal role in the degradation process. A possible degradation mechanism of CAZ, which involved bond breaking, decarboxylation, demethylation, oxidization, and ring-opening, was proposed. The Escherichia coli inhibition experiment showed that the toxicity of CAZ was substantially reduced after electrochemical oxidation. The Ti/Ti4O7-rGO/Ce-PbO2 electrode exhibited a constant degradation efficiency (> 99 %) after 10 consecutive cycles, and its service life can reach 3000 min. Furthermore, CAZ maintained a high removal efficiency in swine wastewater. This study provides a new approach toward fabricating a Ce-PbO2 electrode with Ti4O7-rGO middle layer for the degradation of antibiotics in wastewater.

Z-scheme heterojunction composed of Fe-doped g-C3N4 and Bi2MoO6 for photo-fenton degradation of antibiotics over a wide pH range: Activity and toxicity assessment

In photo-Fenton technology, the narrower pH range limits its practical application for antibiotic wastewater remediation. Therefore, in this study, a Z-scheme heterojunction photo-Fenton catalyst was constructed by Fe-doped graphite-phase carbon nitride in combination with bismuth molybdate for the degradation of typical antibiotics. Fe doping can shorten the band gap and increase visible-light absorption. Simultaneously, the constructed Z-scheme heterojunction provides a better charge transfer pathway for the photo-Fenton reaction. Within 30 min, Fe3CN/BMO-3 removed 95.54% of tetracycline hydrochloride (TC), and its remarkable performance was the higher Fe3+/Fe2+ conversion efficiency through the decomposition of H2O2. The Fe3CN/BMO-3 catalyst showed remarkable photo-Fenton degradation performance in a wide pH range (3.0–11.0), and it also had good stability in the treatment of TC wastewater. Furthermore, the order of action of the active species was h+ > ·O2− >1O2 > ·OH, and the toxicity assessment suggested that Fe3CN/BMO-3 was effective in reducing the biotoxicity of TC. The catalyst proved to be an economically feasible and applicable material for antibiotic photo-Fenton degradation, and this study provides another perspective on the application of elemental doping and constructed heterojunction photo-Fenton technology for antibiotic water environmental remediation.

Assessment of the adsorption capacity tetracycline hydrochloride antibiotic in wastewater of graphene oxide materials

Assessment of the adsorption capacity tetracycline hydrochloride antibiotic in wastewater of graphene oxide materials

Unwinding the correlation between atmospheric pressure plasma jet operating parameters and variation in antibiotic wastewater characteristics

The influence of plasma operating parameters such as gas medium, electrode distance, applied voltage, gas flow rate, and their interdependency on reactive species generation was investigated. Full factorial design-based response surface methodology (RSM) was used to establish the correlation between the operating parameters. The optimization studies were carried out by taking energy yield and degradation efficiency as response parameters. The operating voltage of 9 kV, the airflow rate of 2 LPM, and the electrode distance of 5 mm are optimum for the system studied. The higher voltage of 9 kV and a flow rate of 2 LPM give maximum yield due to the increased rate of gas atoms undergoing ionization. However, at the low voltage (5 kV), the increase in air flow rate from 0.5 to 2 LPM, the energy yield decreases from 67.5 to 54.2 mg/kWh. These observations are further supported by measuring OH (A-X) intensity in an air medium using optical emission spectroscopy. The studies also reveal that the degradation efficiency is adversely affected by scavenges, with a maximum from isopropyl alcohol, followed by tert-butyl alcohol and methanol. TOC and LC-MS analyses established complete mineralization and its degradation pathway. Phytotoxicity studies suggest that treated effluent, rich in nitrates, is suitable for irrigation, promoting seed germination. In short, the studies provide a strategy to optimize the generation of reactive chemical species in a reactor and how such optimization would help attain optimum energy yield, especially when there is a fluctuation in target pollutant concentration.

A novel continuous-flow photocatalytic device for antibiotic degradation

The presence of antibiotic contaminants in water reservoirs and aquatic environments poses considerable risks to public and ecosystem health. Despite its high mineralization efficiency and environmental friendliness, photocatalytic technology has limited practical applications due to low energy efficiency, intermittent operation, and inconvenient catalyst recovery. Here, we developed a continuous-flow photocatalytic device (CFP-D) with outstanding activity, stability, and university towards antibiotic wastewater degradation. Complete removal of total organic carbon was achieved for multiple antibiotic wastewaters using CFP-D in a continuous flow process. The unique combination of continuous-flow reactor and highly photo-permeable F-Ti-SiO2 aerogel with abundant TiO5 active sites overcomes the limitations of conventional photocatalytic devices. This study provides new insights for the design of highly efficient monolithic catalysts and continuous flow reaction devices, and showcases the immense potential of CFP-D in medical and organic wastewater treatment.

Contact-electro-catalysis for degradation of trace antibiotics in wastewater

Antibiotic contamination of water bodies is a major concern in environmental management. Despite their superior efficacy in antibiotic removal, advanced oxidation processes (AOPs) have yet to be widely adopted owing to their substantial cost associated with the large amounts of chemicals required. In this study, a novel contact-electro-catalysis (CEC) process with reusable polytetrafluoroethylene (PTFE) particles as a trigger catalyst was applied to replace traditional AOPs, and it was able to degrade three typical antibiotics (sulfamethoxazole [SMX], ciprofloxacin [CIP], and tetracycline [TET]) in the secondary effluent of a wastewater treatment plant for the first time. The PTFE particles at a concentration of 0.8 g/L were introduced into antibiotic solutions with an antibiotic concentration of 1 mg/L, and the removal rates of SMX, CIP, and TET after a 90-min operation time reached 50 %, 80 %, and 90 %, respectively. Our findings revealed that the CEC reaction generated ●OH and 1O2, contributing substantially to antibiotic degradation. Thus, new reactive oxygen species generation mechanisms during the CEC process were proposed. Furthermore, we fabricated polyvinylidene fluoride nanofiber membranes using electrospinning to recycle PTFE particles, where a nearly 100 % recovery rate through dead-end filtration was realized with a high water flux of 7.5 m3/(m2∙h). The results of this study provide a promising approach for antibiotic removal from wastewater.

Low concentration of peroxymonosulfate coupled with visible light triggers oxygen reactive species generation over constructed Bi25FeO40/BiOCl Z-scheme heterojunction for various tetracycline antibiotics removal

Photocatalytic peroxymonosulfate (PMS) oxidation systems demonstrate significant potential and promising prospects through the interconnection of photocatalytic and PMS oxidation for simultaneously achieving efficient pollutant removal and reduction of PMS dosage, which prevents resource wastage and secondary pollution. In this study, a Z-scheme Bi25FeO40/BiOCl (BOFC) heterojunction was constructed to carry out the photocatalytic PMS oxidation process for tetracyclines (TCs) pollutants at low PMS concentrations (0.08 mM). The photocatalytic PMS oxidation rate of Bi25FeO40/BiOCl composites for tetracycline hydrochloride (TCH), chlortetracycline (CTC), oxytetracycline (OTC) and doxycycline (DXC) reaches 86.6%, 83.6%, 86.7%, and 88.0% within 120 min. Simultaneously, the BOFC/PMS system under visible light (Vis) equally displayed the practical application prospects for the solo and mixed simulated TCs antibiotics wastewater. Based on the electron spin resonance (ESR) and X-ray photoelectron spectroscopy (XPS) valence band spectrum, a Z-scheme electron migration pathway was proposed to elucidate the mechanism underlying the performance enhancement of BOFC composites. Bi25FeO40 in BOFC composites can serve as active site for activating PMS by the formation of Fe3+/Fe2+ cycle. Toxicity estimation software tool (T.E.S.T.) and mung beans planting experiment demonstrates that BOFC/PMS/Vis system can reduce toxicity of TCs wastewater. Therefore, BOFC/PMS/Vis system achieves efficient examination in different water environments and efficient utilization of PMS, which displays a scientific reference for achieving environmentally-friendly and resource-saving handling processes.

Red mud-based CoFe2O4 activated by ball milling as effective peroxymonosulfate activator for the degradation of lomefloxacin hydrochloride: Preparation & activation, application and degradation mechanism

In this study, red mud-based CoFe2O4 (CoFe2O4/RM) was firstly prepared via a sol–gel method, and then activated through ball milling to obtain the catalyst of Ball-milled CoFe2O4/RM (BM-CoFe2O4/RM). The BM-CoFe2O4/RM catalyst was applied as a high-efficiency activator of peroxymonosulfate (PMS) for the degradation of lomefloxacin hydrochloride (LOM-HCl). The LOM-HCl (100 mg/L) could be removed 86.36 % after 12 min treatment under the optimal reaction parameters (BM-CoFe2O4/RM dosage of 1.33 g/L, PMS concentration of 5 mmol/L and nature pH 6.59 ± 0.1). The comparative experiments revealed that the apparent rate constant of LOM-HCl degradation of BM-CoFe2O4/RM (0.1091 min−1) was approximately 1.6 times that of CoFe2O4/RM (0.0701 min−1). A series of characterizations demonstrated that the physicochemical properties of CoFe2O4/RM, including defective structures, crystallinity of high active components, exposures of Co (II) and Fe (II) and electrical conductivity, could be improved via ball milling, causing the increase of the catalytic activity of CoFe2O4/RM. Combined with the results of Electron spin resonance (ESR), X-ray photoelectron spectrometer (XPS) and quenching experiments, the possible catalytic mechanism of PMS activated by BM-CoFe2O4/RM for LOM-HCl degradation was proposed. Combined with the density functional theory (DFT) calculation and liquid chromatography-mass spectrometer (LC-MS), the possible vulnerable sites and possible degradation pathways of LOM-HCl were obtained. The recycling experiments and XPS demonstrated that BM-CoFe2O4/RM had good stability, and the catalytic activity of the BM-CoFe2O4/RM after use could be regenerated by thermal treatment. The biological toxic experiment suggested that the toxicity of LOM-HCl solution treated by the BM-CoFe2O4/RM + PMS system was effectively reduced. The work not only provides a simple and high-efficiency method for improving the catalytic activity of CoFe2O4/RM, but also opens novel insights into the Ball-milled CoFe2O4/RM as an effective PMS activator for antibiotic wastewater treatment.

Direct Z-scheme system of UiO-66 cubes wrapped with Zn0.5Cd0.5S nanoparticles for photocatalytic hydrogen generation synchronized with organic pollutant degradation

Optimized fabrication of Z-scheme photocatalyst based on MOF materials offers sustainable energy generation and environmental improvement due to their attractive properties. The Z-scheme heterojunctions consisting of UiO-66 cubes covered with Zn0.5Cd0.5S nanoparticles were fabricated by a facile solvothermal method. Thanks to the Z-scheme carrier transport under simulated sunlight irradiation, UiO-66@Zn0.5Cd0.5S exhibited enhanced photocatalytic performance of H2 generation synchronized with organic pollutant degradation in fluoroquinolone antibiotic wastewater. Synergistically, the highest comprehensive performance was obtained in ciprofloxacin solution. The H2 yield reached 224 μmol∙ g−1∙ h−1 and simultaneously the removal efficiency was up to 83.6 %. The degradation pathways revealed that the process of piperazine ring cleavage and decarboxylation also generates H protons, further promoting the production of H2. Therefore, the effective spatial separation and transfer of the photoinduced carriers are attributed to the good band structure, large specific surface area, and cooperative reduction and oxidation reactions of UiO-66@Zn0.5Cd0.5S, resulting in significant photocatalytic activity. The toxicity assessment of antibiotics and intermediate products during the photocatalytic reaction also verifies the reduction of environmental risk. This study highlights a promising way to expand the application of the MOFs-based photocatalyst in clean energy conversion coupling with water remediation.

Selective Removal of Penicillin Antibiotics in Wastewater by Rapid Hydrolysis in Goethite-Zn(II) System

Selective Removal of Penicillin Antibiotics in Wastewater by Rapid Hydrolysis in Goethite-Zn(II) System

Natural pyrite-stimulative periodate activation: efficiency and mechanism study.

Natural pyrite (NP) is an alternative catalyst for wastewater purification via advanced oxidation processes (AOPs). However, the activation performance and mechanism of periodate (PI) by NP have not yet been revealed. Herein, this work examines the activation performance of NP towards PI and its application in the degradation of antibiotic wastewater. Interestingly, 95.69% of chlortetracycline (CTC) was degraded by NP within 20min via PI activation. Besides, NP shows effective degradation of various pollutants such as rhodamine B (65.81%), sulfamethoxazole (89.04%), and sodium butylxanthate (99.77%) within 20min. The active species quenching experiment suggested that the active species , , 1O2 and the active complex of PI bonded with NP surface participated in CTC degradation. In addition, Fe(II) on NP surface is the main active site for PI activation, while Sn2- species accelerates the reduction of Fe(III) to Fe(II) and promotes sustained PI activation. This work provides new ideas for the application of NP in environmental pollution control.