Antibiotic Wastewater Research Articles

Removal of metronidazole using a novel ZnO–CoFe2O4@Biochar heterostructure composite in an intimately coupled photocatalysis and biodegradation system under visible light

The intimate coupling of photocatalysis and biodegradation (ICPB) technology has received much attraction because of the advantages of both photocatalytic reaction and biological treatment. In this study, ZnO–CoFe2O4@BC (ZCFC) with p-n heterojunction was prepared and used in an ICPB system to degrade metronidazole (MNZ) wastewater. The microstructure, morphology, and optical behavior of heterojunctions in ZCFC were investigated using SEM, XRD, UV–vis, FTIR, and XPS techniques. The results showed that ZCFC inherited the advantages of bamboo biochar's large pore size, and its large pore structure could provide a habitat for bacterial colonization in ICPB, thus shortening the internal mass transfer distance. The degradation of MNZ and chemical oxygen demand (COD) by the ICPB system was 86.8% and 58.5%, respectively, which was superior to single photocatalysis (72.5% for MNZ and 43.8% for COD) and single biodegradation (23.5% for MNZ and 20.1% for COD). In ICPB, photocatalysis and biodegradation showed a synergistic effect in the removal of MNZ, and the order of the major reactive oxygen species (ROS) leading to reduced toxicity of MNZ to the biofilm was •OH > h+ > O2•-. High-throughput sequencing analysis showed continuous evolution of biofilm structures in ICPB enriched a variety of functional species, among which the electroactive bacteria Alcaligenes and Brevundimonas played an important role in the degradation of MNZ. In this study, we investigated the possible mechanism of photocatalytic and microbial synergistic degradation of MNZ in the ICPB system and proposed a new technology for degrading antibiotic wastewater that combines the advantages of photocatalysis and biodegradation.

Synchronously enhanced dual oxidation pathways via engineered Co-Nx/Co3O4 for high-efficiency degradation of versatile antibiotics

Developing efficient and eco-friendly technologies for treating the antibiotic wastewaters is crucial. At present, the catalysts with metal-nitrogen (M-Nx) coordination showed excellent Fenton-like performance but were always difficult to realize practical antibiotics degradation because of their complicated preparation methods and inferior stability. In this work, the Co-Nx configuration was facilely reconstructed on the surface of Co3O4 (Co-Nx/Co3O4), which exhibited superior catalytic activity and stability towards various antibiotics. DFT results indicated that stronger ETP oxidation will be triggered by the electron-donating pollutants since more electrons can be easily migrated from these pollutants to the Co-Nx/Co3O4/PMS complex. The Co-Nx/Co3O4/PMS system could maintain superior oxidation capacity, high catalytic stability and anti-interference due to (i) the strong nonradical ETP oxidation with superior degradation selectivity in Co-Nx/Co3O4/PMS system, and (ii) the synchronously enhanced radical oxidation with high populations of non-selective radicals generated via activating PMS by the Co-Nx/Co3O4. As a result, the synergies of synchronously enhanced dual oxidation pathways guaranteed the self-cleaning properties, maintaining 98 % of activity after eight cycles and stability across a wide pH range. Basically, these findings have significant implications for developing technologies for purifying antibiotic wastewater.

Degradation of tetracycline by combining hydrodynamic cavitation (HC) and persulfates (PS)

Abstract The ecological and human health risks caused by the overuse of antibiotics have aroused widespread concern. Due to the characteristics of antibiotics themselves, they cannot be effectively removed by traditional treatment methods. HC is considered as a new and innovative chemical process enhancement technique. which exhibits remarkable efficiency in degrading stubborn organic pollutants, and can effectively cooperate with various physical and chemical methods. In this study, the hydrodynamic cavitation (HC) technology was used to activate peroxymonosulfate (PMS) and peroxodisulfate (PDS) to produce strong oxidizing active substances (SO4 -•) to degrade tetracycline (TC) wastewater with an initial concentration of 30 mg/L. The results show that a positive relationship between the degradation efficiency of TC and both the inlet pressure as well as the dose of PS applied. HC can enable full activation of PMS and PS, the max synergistic index of HC-PMS and HC-PDS was 1.72 and 24.81, respectively. Therefore, the HC-PS system can provide a novel technical route for the treatment of antibiotic wastewater.

Levofloxacin removal by 2D-Vermiculite loaded with NiCo2O4 activated peroxymonosulfate: Performance and mechanism

The presence of antibiotics in wastewater threatens the human living environment. Activated peroxymonosulfate (PMS) method is often used for catalytic degradation of antibiotics. However, how to reduce catalyst cost and ensure efficient degradation of antibiotics at the same time is a sticky issue for the activated PMS method. Two-dimensional vermiculite flakes (2D-VMT) is cost-effective and can be used as catalyst carriers for PMS activation. Hence, we exfoliated 2D-VMT from natural vermiculite and prepared NiCo2O4 loaded 2D-VMT (NiCo2O4/2D-VMT) catalyst. Levofloxacin (LVX), as a normal antibiotic, was used to evaluate the catalytic capacity of NiCo2O4/2D-VMT in PMS systems. Also, LVX degradation mechanism through NiCo2O4/2D-VMT activated PMS were explored here. XRD, EDS, TEM, and HRTEM analysis all demonstrated NiCo2O4 nanoparticles were successfully anchored on 2D-VMT. NiCo2O4/2D-VMT had a high specific surface area and abundant active sites. The NiCo2O4/2D-VMT/PMS system, with a 15% mass ratio of NiCo2O4 to 2D-VMT (15%-CN/2D-VMT), achieved LVX removal efficiency of 87% and LVX removal rate of 0.034 min−1. 1O2 and SO4·- were the major ROS for LVX degradation. The reversible redox cycle between Co(III)/Co(II) and Ni(III)/Ni(II) played a crucial role in activating PMS to generate ROS for LVX degradation process. Also, based on intermediates identification by LC-MS, possible degradation pathways of LVX were proposed and their ecotoxicological evolution was assessed by using the ECOSAR software. 15%-CN/2D-VMT may be a worth recommended loaded catalyst for antibiotics removal in environmental remediation, owing to its high reusability and excellent renewability.

Efficient sulfamethoxazole removal, water recovery and electricity generation were achieved simultaneously by osmotic microbial fuel cell in treating antibiotic wastewater

Microbial fuel cell (MFC) processes are associated with poor effluent quality when treating antibiotic wastewater. This study innovatively applied osmotic microbial fuel cell (OsMFC) technology to treat antibiotic wastewater while achieving the efficient removal of sulfamethoxazole (SMX), producing high-quality water, and generating electricity. During the stable operation of the OsMFC system, the chemical oxygen demand (COD) removal efficiency reached 80.1%, and the SMX removal efficiency reached 99.3% owing to forward osmotic membrane interception and biodegradation. The high-quality water production rate was 25% ± 5%. Interestingly, the addition of SMX improved the electrochemical performance of the system. The maximum power density was 4,642.4 mW/m3, and the internal resistance was only 230.7 Ω. During long-term operation of the system, membrane fouling was slight, and proteins were the main component of the fouling, followed by α-D glucopyranose polysaccharides and β-D glucopyranose polysaccharides. This study provides a new approach for the treatment of antibiotic wastewater and a novel method for the biodegradation of challenging emerging pollutants.

Nickel-doped red mud-based Prussian blue analogues heterogeneous activation of H2O2 for ciprofloxacin degradation: waste control by waste.

Red mud (RM) is a typical bulk solid waste with Fe/Al/Si/Ca-rich characteristics that has been used to prepare various heterogeneous catalysts such as iron-based catalysts and supported catalysts. Prussian blue analogues (PBA) is a low-cost, environmentally friendly, and active site rich iron-based metal organic framework, but its catalytic properties are adversely affected by their easy aggregation. In this study, nickel-doped RM-based PBA (RM-Ni PBA) was synthesized by acid dissolution-coprecipitation method for the degradation of ciprofloxacin (CIP). The characterization showed that RM-Ni PBA was a material with excellent dispersibility, large specific surface area, and abundant active sites. The degradation results showed that the removal efficiency of CIP in the RM-Ni PBA/H2O2 system was 16.63, 1.78, and 1.81 times that of RM, RM-PB, and Ni PBA, respectively. It was found that 1O2 was the main reactive oxygen species (ROS) dominated the degradation process, and its formation was accompanied by the mutual conversion of Ni(II)/Fe(II) and Ni(III)/Fe(III). Notably, the degradation process maintained a satisfactory efficiency over a wide pH range (3-9) and exhibited strong anti-interference ability against impurities such as Cl-, SO42-, and NO3-. The components and contents of RM-Ni PBA remained relatively stable during the degradation process. In addition, the degradation intermediates of CIP were identified, and possible degradation pathways were proposed. This study is expected to provide theoretical basis and technical guidance for the application of RM-based heterogeneous catalyst in the treatment of antibiotic wastewater.

Hydrothermal synthesis of Zingiber/ZnO for enhanced photodegradation of ofloxacin antibiotic and reactive red azo dye (RR141).

The examination of photocatalyst powders for the total removal of pollutants from aqueous solutions is a vital research subject within the realm of environmental preservation. The objective of this study is to develop a photocatalyst heterojunction consisting of Zingiber/ZnO-H for the degradation of both the reactive red dye (RR 141) and ofloxacin antibiotic in wastewater. The current investigation outlines the process of synthesising a composite material by combining Zingiber montanum extract with zinc oxide (ZnO) by a hydrothermal method. The synthesis was conducted at a temperature of 180°C for a period of 4 hours. Consequently. The photocatalyst with a constructed heterojunction shown a notable enhancement in its photocatalytic activity as a result of the improved efficiency in charge separation at the interface. The application of economically viable solar energy facilitated the complete eradication of harmful pollutants through the process of detoxification. The removal of impurities occurs by a process that follows a first-order kinetics. Among the pollutants, RR141 demonstrates the greatest rate constant at 0.02 min-1, while ofloxacin has a rate constant of 0.01 min-1. The assessment of the stability of the produced photocatalyst was conducted after undergoing five cycles. This study additionally investigated the influence of sunshine on degradation, uncovering degradation rates of 97% for RR141 and 99% for ofloxacin when exposed to UV Lamp, and degradation rates of 97% for RR141 and 95% for ofloxacin when exposed to Solar Light.

A Type-II CQDs regulating FeOOH decorated BiVO4 photoelectrode for highly efficient photoelectrochemical degradation of tetracycline

Bismuth vanadate (BiVO4) photoelectrode is of great potentials to be used for photoelectrochemical (PEC) removal of antibiotic pollutant. However, it still suffers from lower efficiency. Herein, a type-II FeOOH-CQDs/BiVO4 photoelectrode was fabricated via the in-situ growth of FeOOH nanoparticles over BiVO4 using Carbon quantum dots (CQDs) as mediator. Benefiting from the type-II heterojunction between BiVO4 and FeOOH, as well as the excellent charger transfer assisted by CQDs, FeOOH-CQDs/BiVO4 exhibited excellent PEC degradation performance towards a typical antibiotic- tetracycline (TC). In a typical PEC process, FeOOH-CQDs/BiVO4 photoelectrode (2 cm × 2 cm) yielded a high removal ratio of ∼ 99 % toward TC within 120 min at an applied potential of 0.6 V (vs. Hg/Hg2Cl2). Moreover, the PEC configuration was verified to be used for TC degradation in actual waters, such as tap water and lake water, with > 90 % of removal ratio. The radical trapping experiments revealed holes and superoxide radical dominated in the TC degradation process. This work provides an insight on the type-II heterojunction photoelectrode to enhance the PEC degradation of TC, which would help for the treatment of antibiotic wastewater.

The efficiency of a granular Fe-based metal-organic framework for the persulfate oxidative degradation of levofloxacin, an emerging antibiotic in wastewater

This study presents a novel approach to solve the problems of leaching and regeneration of metal–organic frameworks (MOFs) in water treatment. The researchers developed a modified MOF by encapsulating MIL-88(Fe) with alginate. The modified MOF was then used to activate sulfate radicals with sodium persulfate for the degradation of levofloxacin (LVX) in water. Various characterization techniques, including XRD, FTIR, BET, FESEM, TG and EDS mapping, confirmed the successful synthesis of the modified MOF and revealed its characteristic facets. The catalytic and adsorptive abilities of the modified MOFs were investigated and sodium persulfate was found to be more effective than hydrogen peroxide in the degradation of LVX. Optimal degradation conditions were determined at a pH of 3, a concentration of 2.5 mM Na2S2O8 and a catalyst dosage of 0.75 g/L. The researchers also found that higher temperatures improved the removal of LVX. The granulated MOF showed remarkable stability over five cycles, although the performance gradually decreased, indicating its potential for long-term applications in water treatment. The inhibitory properties of isopropyl alcohol and ethanol suggest that sulfate radicals rather than hydroxyl radicals are involved in the degradation of LVX. In addition, the functional groups of levofloxacin, including the piperazine ring, the carboxylic acid group and the fluorine substituents, were identified as potential initiation sites for oxidation.

Visible light driven mesoporous ag/Ag2CrO4/g-C3N4 degrades multiple organic pollutants efficiently: Synthesis, mechanism, and degradation pathway

With the development of economy, overuse of antibiotics has been seen as a huge threat to human health. Photocatalytic degradation is an effective method for resolving this problem at present. The method of combining plasmon resonance effect and Z-scheme heterojunction can effectively improve the separation efficiency of photogenerated carrier, which is of great significance for the treatment of antibiotic wastewater. Herein, the Ag/Ag2CrO4/g-C3N4 catalyst was prepared by in-situ loading and photo-reduction method for the degradation of antibiotic wastewater containing tetracycline and quinolone antibiotics. The research results showed that mesoporous graphitized carbon nitride (denoted as g-C3N4) provided good support for Ag and Ag2CrO4 nanoparticles, and mesoporous composite Ag/Ag2CrO4/g-C3N4 (denoted as ACO/CN) provided more reaction sites for organic pollutants degradation. Under visible light irradiation, 5%ACO/CN catalyst showed the best degradation activity and stability for tetracycline (TC), levofloxacin (LVFX), oxytetracycline hydrochloride (OTC) and norfloxacin (NFLX), and their degradation rate constants were respectively 5.66, 8.26, 11.72 and 15.97 times of Ag2CrO4 which indicated it had good potential application value in the treatment of wastewater containing various organic pollutants. This benefits from the plasmon resonance effect of silver effectively improves the utilization efficiency of visible light and the Z-scheme heterojunction between Ag2CrO4 and g-C3N4 promotes the rapid transmission of photogenerated carriers. Based on the experimental results, the possible TC degradation pathway and photocatalytic mechanism were proposed. This study provides a simple way for the successful design and preparation of plasmon resonance effect synergistic Z-scheme heterojunction with promising applications in the treatment of antibiotic wastewater.

Knowledge graph and development hotspots of biochar as an emerging aquatic antibiotic remediator: A scientometric exploration based on VOSviewer and CiteSpace

As an emerging material in the field of environmental remediation, biochar produced by carbonisation of organic solid waste has been widely used in the remediation of antibiotic wastewater due to its environmental friendliness and excellent adsorption properties. This study analyses the current literature in the field in a comprehensive and scientific manner using CiteSpace and VOSviewer technologies. Between 2011 and 2023, a total of 1162 papers were published in this domain, spanning three distinct stages: applied methods, mechanism investigation, and enhanced improvement. The results of keyword clustering indicate that the remediation of antibiotics complexed with multiple pollutants by biochar is the main research topic, followed by the remediation of antibiotics by biochar in combination with other technologies. Furthermore, drawing from current research hotspots in antibiotic remediation using biochar, this study identified the pivotal mechanisms involved: (1) The primary mechanisms by which raw biochar remediates antibiotics include π-π electron donor-acceptor interactions, hydrophobic interactions, electrostatic interactions, hydrogen-bonding, and pore filling. (2) Steam activation, acid/base, metal salt/metal oxide, and clay mineral modification can improve the physical/chemical properties of biochar, enhancing its adsorptive removal of antibiotics. (3) Biochar activated persulfate and degraded antibiotics via free radical pathways (SO4−•, •OH and O2−•) as well as non-free radical pathways (1O2 and electron transfer). In addition, the challenge and prospect of biochar engineering applications for antibiotic remediation lies in improving the main mechanism of antibiotic remediation by biochar. The prospective utilization of biochar in enhancing the remediation of antibiotic-related pollutants holds tremendous value for the future.

Intermittent electrical stimulation removes mixed antibiotics and associated antibiotic resistance genes at low temperatures

Biotechnology has limited effectiveness in terms of removing mixed antibiotics at low temperatures, leading to ecological risks arising from the presence of antibiotics in environmental waters. In this study, the removal of tetracycline (TCs) and sulfonamide (SAs) from antibiotic wastewater was improved by the intermittent electrical stimulation of anaerobic-aerobic-coupled upflow bioelectrochemical reactors (AO-UBERs) at low temperatures. The removal effects of oxytetracycline and tetracycline were 48.6 ± 3.5 % and 71.5 ± 2.9 %, respectively. Under 0.9V, the removal rates of oxytetracycline, tetracycline, and trimethoprim were significantly increased in both the aerobic-cathodic and anaerobic anodic chambers, with a more obvious increase at low temperatures. Compared with the blank control group, the removal efficiency of oxytetracycline, trimethoprim and tetracycline in the electric group was increased by 11.8 ± 2.5 %, 27.8 ± 10.5 % and 11.2 ± 5.8 %. The anaerobic chamber contributed more to the removal of TCs and trimethoprim than the aerobic chamber. Furthermore, electrical stimulation selectively enriched electroactive bacteria (Methylophage and Pleuromonas), drug-resistant bacteria (Proteobacteria), and nitrifying bacteria associated with biodegradation. The abundance of antibiotic-resistance genes is related to the distribution of potential hosts and mobile genetic elements (sul1), and electrical stimulation induces the enrichment of both. This suggests that while potentially effective for treating TCs- and SAs-containing wastewater at low temperatures, AO-UBERs may lead to the accumulation of antibiotic-resistance genes.

Preparation of mesoporous biogas residue biochar via a self-template strategy for efficient removal of ciprofloxacin: Effect of pyrolysis temperature

Biochar preparation and application is an anticipated pathway for the resource utilization of biogas residue. In this study, biochars were prepared by the pyrolysis of biogas residue from food waste anaerobic digestion (named as BRBCs) under various pyrolysis temperatures (300, 500, 700, and 900 °C), and the effect of pyrolysis temperatures on the physicochemical characteristics of BRBCs was examined. The adsorption performance toward ciprofloxacin (CIP), a typical antibiotic in waterbodies, was also investigated. The results showed that pyrolysis temperature significantly changed the physicochemical properties of BRBCs. In addition, the minerals in the biogas residue, especially SiO2, were rearranged to form a mesoporous structure in biochar through a self-template strategy (without activator). BRBC prepared at 900 °C exhibited a high specific surface area and pore volume, well-developed mesopore structure, and more carbon structure defects, and exhibited the largest CIP adsorption capacity with 70.29 mg g−1, which was ascribed to the combined interaction of pore diffusion, π–π interactions, hydrogen bonding, complexation, and electrostatic forces. Furthermore, the adsorption of CIP by BRBC900 was well described by two-compartment kinetic and Langmuir isotherm models. BRBC900 showed good adsorption performance toward CIP at pH 7–9. The adsorption of CIP by BRBC is a spontaneous, exothermic, entropy-increasing process. Moreover, BRBC also presented a good recycling potential. Therefore, the preparation of mesoporous biochar based on a self-template strategy not only provides an option for the resource utilization of biogas residue but also offers a new option for the treatment of antibiotic wastewater.

A waste-to-wealth conversion of plastic bottles into effective carbon-based adsorbents for removal of tetracycline antibiotic from water

Currently, plastic waste and antibiotic wastewater are two of the most critical environmental problems, calling for urgent measures to take. A waste-to-wealth strategy for the conversion of polyethylene terephthalate (PET) plastic bottles into value-added materials such as carbon composite is highly recommended to clean wastewater contaminated by antibiotics. Inspired by this idea, we develop a novel PET-AC-ZFO composite by incorporating PET plastic-derived KOH-activated carbon (AC) with ZnFe2O4 (ZFO) particles for adsorptive removal of tetracycline (TTC). PET-derived carbon (PET-C), KOH-activated PET-derived carbon (PET-AC), and PET-AC-ZFO were characterized using physicochemical analyses. Central composite design (CCD) was used to obtain a quadratic model by TTC concentration (K), adsorbent dosage (L), and pH (M). PET-AC-ZFO possessed micropores (d ≈ 2 nm) and exceptionally high surface area of 1110 m2 g−1. Nearly 90% TTC could be removed by PET-AC-ZFO composite. Bangham kinetic and Langmuir isotherm were two most fitted models. Theoretical maximum TTC adsorption capacity was 45.1 mg g−1. This study suggested the role of hydrogen bonds, pore-filling interactions, and π-π interactions as the main interactions of the adsorption process. Thus, a strategy for conversion of PET bottles into PET-AC-ZFO can contribute to both plastic recycling and antibiotic wastewater mitigation.

Photo-Fenton-like degradation of tetracycline through peroxymonosulfate activation over 2D BiOBr/FeOOH nanosheets and membrane application

The selection of photosensitizer substrates with high photocatalytic efficiency is crucial for leveraging the advantages of metal-based materials in photo-Fenton-like process. Herein, we report a novel 2D layered BiOBr/FeOOH nanosheets equipped with a built-in electric field (BIEF) to activate peroxymonosulfate (PMS) for the degradation of tetracycline (TC). The photocatalytic efficiency of BiOBr is enhanced by fine-tuning the Br source quantity. Both experimental and theoretical analyses confirm that BIEF at the BiOBr/FeOOH heterointerface expedites the movement of photogenerated electrons, significantly boosting both photocatalytic and photo-Fenton-like activities. The BiOBr/FeOOH + PMS + Vis system exhibits a high TC removal rate of 96 % with only 0.24 mM of PMS and nearly 100 % of PMS utilization. Moreover, affixing BiOBr/FeOOH nanosheets onto a PVDF microfiltration membrane, we establish a continuous flow reactor system for antibiotic wastewater treatment. This system demonstrates a remarkable TC removal efficiency consistently above 97.5 % for 6 h of continuous injection, underscoring its practicality and potential for real-world applications.

Bacterial cellulose-supported dual-layered nanofibrous adsorbent for thin-film micro-solid-phase extraction of antibiotics in municipal wastewaters

In this study, bacterial cellulose was coated with composite nanofibers of polyvinyl alcohol doped with beta cyclodextrin and alginate (PVA-SA-βCD), constructed using the electrospinning technique. This novel material served as an effective adsorbent for thin-film micro-solid-phase extraction (TF-μSPE) of antibiotics from water samples, followed by HPLC-UV analysis. The adsorbent was subjected to a comprehensive characterization using ATR-FTIR, FE-SEM, and BET techniques. These analyses provided valuable insights into its physicochemical structure and properties. Several key parameters that affect the performance of the TF-μSPE method were investigated including electrospinning factors (voltage, flow rate, needle tip-collector distance, and electrospinning time), desorption solvent type and volume, adsorbent dose, adsorption and desorption times, pH value, and salt percentage. Under the optimized conditions, the limits of detections and quantifications for target antibiotics were obtained in the ranges of 0.02–0.03 and 0.07–0.1 μg L⁻1, respectively. The linear range was 0.07–1000 μg L⁻1 with satisfactory determination coefficients (r2) of 0.9944–0.9984. The intra-day and inter-day precisions were obtained as 1.1–1.7 % and 2.2–3.5 %, respectively. The developed method was successfully applied to determine antibiotics in municipal wastewater samples, yielding recoveries within the range of 70–100 % (RSD%<3.7). The green features of the method were also assessed based on AGREE tool. This is the first report on the fabrication of a double-layered nanofibrous adsorbent and its application for the adsorption of antibiotics in wastewater. This robust approach combines efficiency with analytical accuracy, making it a valuable tool for antibiotic analysis in environmental samples.

2D MoS2 nanosheets supported CoFe2O4 nanoparticles mediated persulfate activation for antibiotic removal

Advanced oxidation technology based on persulfate activation has caused extensive concern in the field of wastewater treatment. Nevertheless, this new technology is limited to the low catalytic efficiency and poor recovery of powder catalysts. Herein, we successfully synthesized MoS2 surface-supported CoFe2O4 nanoparticles composite catalyst employing a simple hydrothermal method. Compared with other systems, the performance of TC degradation was significantly improved by CoFe2O4/MoS2/PS system. Additionally, the influence of solution pH, catalyst dosage, PS dosage, and co-existing ions on the degradation process were studied. Both free radical (O2•−, •OH, SO4•−) and non-free radical (1O2) pathways coexisted in the catalytic degradation of TC on the account of radicals quenching experiments and electron spin resonance (ESR) technique. Additionally, the degradation pollutants were confirmed to display obvious decrease in toxicity based on microbial toxicology tests. Besides, CoFe2O4/MoS2 nanocomposite displays good magnetic recovery performance due to the introduction of CoFe2O4. In summary, this research provides a solid foundation for the application of magnetic CoFe2O4/MoS2 nanocomposite in the treatment of antibiotic wastewater.

Efficient antibiotic remediation from wastewater using a lamellar free-standing 2D graphene oxide/Ti3C2Tx hybrid membrane

The existence of elevated levels of antibiotics in wastewater has facilitated the emergence and spread of pathogens with antimicrobial resistance (AMR). When combined with the worldwide water scarcity issue, this situation results in detrimental impacts on both the ecosystem and human well-being. Traditional methods employed by wastewater treatment facilities exhibit limited effectiveness in eliminating antibiotics. This paper describes the synthesis and performance of two-dimensional (2D) lamellar free-standing graphene oxide (GO)/Ti3C2Tx membrane for the removal of antibiotics from wastewater. The 50 %GO/Ti3C2Tx composite membrane demonstrated a remarkable increase in water flux, achieving 61.9 L m−2 h−1, surpassing the performance of the pristine GO membrane, which achieved 22.8 L m−2 h−1. Additionally, the GO/Ti3C2Tx composite membranes exhibited outstanding tetracycline rejection, consistently exceeding 99 %, a significant improvement compared to the pristine Ti3C2Tx membrane. The composite membranes of with a ratio of GO to MXene of 50 %, 40 %, 30 % and 20 % had contact angles of 54.5°, 57.4°, 60.6°, and 61.6°, respectively. Combining GO and Ti3C2Tx at specific mass ratios enhanced properties, evidenced by altered interlayer spacing and hydrophilicity. Furthermore, the superior composite membrane demonstrated superior antifouling properties compared to both pristine GO and Ti3C2Tx membranes.

A new type Co(II)-based photocatalyst for the nitrofurantoin antibiotic degradation

Coordination polymers (CPs) are a special class of multidimensional materials that can be employed for the photocatalytic degradation of antibiotics in wastewater. In this paper, a new Co(II)-based coordination polymer with the molecular formula {[Co(H2L)(dpa)(H2O)]·H2O}n (1), (H4L = 1,1′:2′,1″-triphenyltetracarboxylic acid, dpa = 1,2-di(pyridin-4-yl)diazene) was synthesized and characterized. Single-crystal x-ray diffraction results showed that 1 formed a 2D layered structure, which was stacked into a three-dimensional (3D) supramolecular structure through hydrogen-bonding interactions. In addition, the results of the photocatalytic experiments showed that 1 possesses good photocatalytic activity at nitrofurantoin (NFT). The photocatalytic mechanism has been discussed in detail.

Tailoring BiOBr Photocatalyst: In-situ Bi Doping for Enhanced Photocatalytic Removal of Sulfamethoxazole, SMX Antibiotic

There is a notable emphasis on the development of photocatalysts to degrade antibiotics, such as sulfamethoxazole (SMX), in aquatic environments due to their persistence and associated toxicological impacts. In this study, BiOBr photocatalysts were synthesized by incorporating in-situ Bi doping. Various Bi/BiOBr composites were produced through a hydrothermal method at varying temperatures and subsequently characterized using X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy (UV-vis DRS), X-ray fluorescence (XRF), and nitrogen adsorption-desorption isotherm. The characterization data revealed that the Bi-metal began to emerge at a hydrothermal temperature of 180 °C (BB180) in the BiOBr-based semiconductor and completed its conversion to Bi-metal at a hydrothermal temperature of 270 °C (BB270). This transformation leads to the generation of Bi3+ in conjunction with oxygen vacancies, acting as active electron traps and enhancing the separation efficiency of light-induced electron-hole pairs. This results in a narrow band gap of Bi/BiOBr photocatalyst, increasing its sensitivity towards visible light. BB180 exhibited the highest photocatalytic rate in the degradation of SMX with a removal efficiency of 74.35% within 4 hours of reaction under Xenon lamp irradiation and an apparent rate constant of 6.5 x 10-3 min-1, surpassing the commercial TiO2 Degussa P25. This finding opens up a new pathway for the development of a catalyst responsive to visible light, specifically designed for the detoxification of antibiotics in wastewater.