Adsorption Of Oxytetracycline Research Articles

Hexagonal Fe-based MIL-88B nanocrystals with NH2 functional groups accelerating oxytetracycline capture via hydrogen bonding

Here, the importance of hydrogen bonding from amino (NH2) functional group on NH2−MIL-88B in oxytetracycline (OTC) adsorption mechanism has been reported. To clarify this finding, two materials including MIL-88B and NH2−MIL-88B derived from two different ligands of 1,4-benzene-dicarboxylic acid (H2BDC) and 2-aminobenzene-1,4-dicarboxylic acid (NH2-BDC) were synthesized and characterized. The X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT–IR) were adopted, and proving the existence of NH2 functional group in the material structure. Comparing the adsorption efficiency among adsorbents with/without NH2 groups was evaluated through several fundamental investigations including the effect of solution pH (3.2–10.8), Na+ ionic strength (25–800 mmol/L), contact time (0–120 min) and initial concentration (20–100 mg/L). The investigations indicated that the best adsorption condition was found at pH 5.7. The OTC sorption process reached out the equilibrium nature rapidly, at 60 min. It was also demonstrated the negligible effect of Na+ ions on OTC adsorption over both MIL-88B and NH2-MIL-88B Some statistical error functions (R2, MRE, χ2, HYBRID, and MPSD) were also selected for better evaluating several nonlinearised kinetic and isothermal models. The principal outcomes revealed that the maximum adsorption capacity (94.9 mg/g) obtained from Langmuir equation by NH2−MIL-88B was above 4-fold higher than that by MIL-88B. Based on these vital evidences, the role of hydrogen bonding and plausible mechanisms in accelerating OTC adsorption has been suggested.

Facile Fabrication of Flocculent Magnesium Silicate for the Adsorption of Oxytetracycline.

The discharge of antibiotics and the potential threat to organisms posed by this have received increasing attention. In this work, flocculent magnesium silicate (FMS) was fabricated by a facile hydrothermal and freeze-drying process, and its adsorption behavior for antibiotic oxytetracycline (OTC) was investigated. FMS presented a sepiolite-type structure and the alkaline solution promoted its hydroxylation. A hierarchical pore structure ranging from micropores to macropores and a high specific surface area of 660 m2/g were exhibited. FMS exhibited a higher adsorption amount in neutral solution than in acidic or alkaline conditions as the physicochemical properties of FMS and OTC were significantly affected by the pH. Adsorption isotherm could be well-described by the Langmuir model, and the calculated saturated adsorption capacity was as high as 265 mg/g. Adsorption kinetics followed the pseudo-second-order kinetic model, and the adsorption rate-controlling step was intraparticle diffusion. Thermodynamic parameters indicated that the adsorption was a spontaneous physicochemical reaction. After five cycles, around 91% of the adsorption performance was still maintained, demonstrating the excellent reusability of FMS. The sepiolite-type FMS fabricated in this work could be applied to remove OTC from wastewater.

Singlet oxygen mediated the selective removal of oxytetracycline in C/Fe3C/Fe0 system as compared to chloramphenicol

Reactive oxygen species (ROS) production for Fe0 is limited because of the formed iron corrosion products. In this study, C/Fe3C/Fe0 composite which produces enhanced ROS has been specifically designed and fabricated to remove typical antibiotics (i.e., oxytetracycline (OTC) and chloramphenicol (CAP)) as a heterogeneous Fenton-like catalyst. The C/Fe3C/Fe0 composite demonstrated excellent performance for both OTC and CAP removal as compared with Fe0 and biochar. Furthermore, X-ray photoelectron spectrometry, Fourier transform infrared spectrometry, high performance liquid chromatography-mass spectra and electron spin resonance analyses were conducted to elucidate the adsorption and degradation mechanisms. The adsorption of OTC and CAP was mainly dominated by H bonds and the electron-acceptor-acceptor on the surface of the C/Fe3C/Fe0 composite, respectively. In particular, OH simultaneously induced the degradation of OTC and CAP, while 1O2 presented the selective oxidation to OTC. More specifically, the degradation of OTC over C/Fe3C/Fe0 was stronger and faster than that of CAP, leading to 65.84% and 16.84% of removal efficiency for OTC and CAP, respectively. Furthermore, C/Fe3C/Fe0 exhibited superior reusability and stability after regeneration, but regenerated Fe0 almost lost its reactivity. Therefore, the efficiency in situ generation of 1O2 using C/Fe3C/Fe0 would shed new light on the selective oxidation of aqueous organic compounds.

Cetyltrimethylammonium bromide functionalized silica nanoparticles (MSN) synthesis using a combined sol-gel and adsorption steps with enhanced adsorption performance of oxytetracycline in aqueous solution

The cetyltrimethylammonium bromide (CTAB)-functionalized silica nanoparticles (MSN) were prepared using a combined sol-gel and adsorption steps. The nitrogen adsorption-desorption surface analysis shows the MSN has a lower surface area than the unmodified (or free) silica nanoparticles (FSN). The energy dispersive X-ray (EDX) and Fourier transform infrared (FTIR) analysis confirmed the presence of CTAB in MSN with maximum CTAB coverage of (0.74 ± 0.04) mmol/g. The maximum adsorption capacity of oxytetracycline (OTC) onto MSN performed in the batch adsorption process, Qe.max is 449.89 µmol g−1, which is higher than FSN (57.06 µmol g−1). The adsorption depends on pH value, OTC concentration, temperature, and contact time. The thermodynamic parameters indicate the process as exothermic in nature and spontaneous. The isotherm data fits well with the Redlich-Peterson model, while the pseudo-second order (PSO) kinetic model is found to be suitable to describe the kinetic data with the film diffusion as the rate-limiting step. The electrostatic, hydrogen bonding and hydrophobic interactions are mainly responsible for the OTC adsorption onto the synthesized adsorbents. The reusability studies found that the adsorbent could be recycled without drastic adsorption capacity reduction. The successful decoration of the CTAB onto the surface of the silica nanoparticles provides an effective method in the development of promising adsorbents for antibiotic removal from wastewater.

Optimization of synergistic biosorption of oxytetracycline and cadmium from binary mixtures on reed-based beads: modeling study using Brouers-Sotolongo models.

The first aim of this study was to synthesize and characterize reed-based-beads (BBR), an enhanced adsorbent from Tunisian reed. The second purpose was to evaluate and optimize the BBR efficiency for the simultaneous removal of oxytetracycline (OTC) and cadmium (Cd(II)), using central composite design under response surface methodology. The third goal was to elucidate the biosorption mechanisms taking place. It was shown that under optimum conditions (4.19 g L-1 of BBR, 165.54 μmol L-1 of OTC, 362.16 μmol L-1 of Cd(II), pH of 6, and 25.14-h contact time) the highest adsorption percentages (63.66% for OTC and 99.99% for Cd(II)) were obtained. It was revealed that OTC adsorption mechanism was better described by Brouers-Sotolongo fractal equation, with regression coefficient (R2) of 0.99876, and a Person's chi-square (χ2) of 0.01132. The Weibull kinetic equation better explained Cd(II) biosorption (R2 = 0.99959 and χ2 = 0.00194). FTIR and isotherm studies confirmed that the BBR surface was heterogeneous, and that adsorption mechanisms were better described by the Freundlich/Jovanovich equation (R2 = 0.99276 and χ2 = 0.04864) for OTC adsorption, and by the Brouers-Sotolongo model (R2 = 0.9851 and χ2 = 0.77547) for Cd(II) biosorption. Overall results indicate that, at last, the BBR lignocellulosic biocomposite beads could be considered as cost-effective and efficient adsorbent, which could be of socioeconomic and environmental relevance. Graphical abstract.

Effective adsorption of oxytetracycline from aqueous solution by lanthanum modified magnetic humic acid

In this study, Fe3O4-HA-La composite was prepared by chemical coprecipitaion method, and the oxytetracycline (OTC) adsorption efficiency of the obtained adsorbent was investigated with batch experiment. Characterization methods, including BET, SEM, XRD, FTIR, XPS and VSM, were employed to study its physiochemical properties. The batch experiment results indicated that > 90 % of OTC was removed using the adsorbent Fe3O4-HA-La under wide pH range from 5–9. The regeneration experiment showed that after three cycles of adsorption/regeneration, Fe3O4-HA-La kept the OTC removal efficiency > 80 % and saturation magnetization (Ms) value > 55 emg g−1. The OTC adsorption process was better fitted with pseudo-second-order kinetic model. The OTC adsorption process was better fitted with Redlich-Peterson model (R2 > 0.99). High correlation coefficient (R2 > 0.97) was also observed for Langmuir model, which showed the Qmax of 23.43 mg g−1. The complexation reaction between OTC and HA, La and Fe on Fe3O4-HA-La were contributed to the efficient removal of OTC by Fe3O4-HA-La.

Superior Adsorption and Photocatalytic Degradation Capability of Mesoporous LaFeO3/g-C3N4 for Removal of Oxytetracycline

Mesoporous LaFeO3/g-C3N4 Z-scheme heterojunctions (LFC) were synthesized via the incorporation of LaFeO3 nanoparticles and porous g-C3N4 ultrathin nanosheets. The as prepared LFC were characterized by transmission electron microscopy, scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, powder X-ray diffraction, Raman spectra and N2 adsorption analysis. The structural analysis indicated that the reheating process and the addition of NH4Cl in the thermal polymerization were the key factors to get porous g-C3N4 ultrathin nanosheets and to obtain high specific surface areas of LFC. It remarkably enhanced the adsorption capacity and photocatalytic degradation of LFC for removal of oxytetracycline (OTC). The effect of the mass percentage of LaFeO3 in LFC, pH and temperature on the OTC adsorption was investigated. The LaFeO3/g-C3N4 heterojunction with 2 wt % LaFeO3 (2-LFC) exhibited highest saturated adsorption capacity (101.67 mg g−1) and largest photocatalytic degradation rate constant (1.35 L g−1 min−1), which was about 9 and 5 times higher than that of bulk g-C3N4 (CN), respectively. This work provided a facile method to prepare mesoporous LaFeO3/g-C3N4 heterojunctions with especially well adsorption and photocatalytic activities for OTC, which can facilitate its practical applications in pollution control.

The key factors and removal mechanisms of sulfadimethoxazole and oxytetracycline by coagulation.

The effects of coagulant dosage, alkalinity, turbidity, ionic strength, and dissolved organic matter (DOM) on the removal of sulfadimethoxazole (SMZ) and oxytetracycline (OTC) by coagulation were studied and the reaction mechanisms of the coagulation process were revealed in this research. From our results, alkalinity, turbidity, ionic strength, and DOM had different effects on the removal of antibiotics. The SMZ and OTC removals were improved with increase in poly-aluminum chloride (PACl) dosage, whereas the turbidity had less influence on the removal of SMZ and OTC because the adsorption of SMZ and OTC to kaolin was low, confirmed by a control when no PACl added. The hydrolysate of PACl played a more important role than turbidity in SMZ and OTC removals. The SMZ and OTC removals were significantly increased with the increase in alkalinity, which provided a suitable condition in situ for coagulant to form more optimal species of hydrolysate. The ionic strength, which was adjusted by NaNO3, also had a positive effect on the removal of SMZ but no obvious effect on the OTC removal. Furthermore, DOM had a higher effect on the removal of SMZ than that of OTC. In another word, if a water plant wants to improve the removal of SMZ and OTC by coagulation unit, PACl hydrolysate, alkalinity, and DOM are the three key factors to be considered primarily. Moreover, an experiment for the recovery of antibiotics from the flocs was done and the results showed that OTC and SMZ were removed by different mechanisms. The OTC was removed via complexation formed through the reaction between OTC and coagulant while the SMZ was removed through the pathway of adsorption and inter-particle bridging to the surface of coagulant hydrolysate.

Adsorption Characteristics of Oxytetracycline by Different Fractions of the Organic Matter from Humus Soil: Insight from Internal Structure and Composition.

For minimizing the transport of antibiotics to groundwater, the migration of antibiotics in soils should be investigated. Soil organic matter can affect the migration of antibiotics. To date, the influence of aromatics and aliphatic content of organic matter on the adsorption of antibiotics has been controversial. To better understand the reaction mechanism of soil organic matter with antibiotics, this study investigated the adsorption of oxytetracycline (OTC) by humus soils (HOS) and their fractions. HOS were sequentially fractionated into four organic fractions, including the removal of dissolved organic matter (HRDOM), removal of minerals (HRM), removal of free fat (HRLF), and nonhydrolyzable organic carbon (HNHC). Moreover, batch experiments revealed that adsorption capacity was ordered by HNHC > HOS > HRDOM > HRLF > HRM. SEM images and N2 adsorption/desorption isotherms indicate that adsorption capacity is independent of the external structure. However, adsorption capacity is related to the internal structure and composition. Combination analysis with elemental composition and infrared spectroscopy showed that the adsorption capacity of HRM, HRLF, and HNHC had a good positive correlation with aromaticity, but a negative correlation with polarity and hydrophilicity. Additionally, the rule of binding affinity between OTC and functional groups with different properties was summarized as aromatic > polarity > hydrophilic.

Preparation of micro-mesoporous carbon from seawater-impregnated sawdust by low temperature one-step CO2 activation for adsorption of oxytetracycline

Porous carbons (PCs) were prepared from seawater (SW)-impregnated sawdust (SD) by CO2 activation at 700 °C. The preparation process was investigated on-line by thermogravimetric analyzer coupled with FTIR (TG-FTIR). PCs were characterized by N2-adsorption/desorption and Fourier transform infrared spectroscopy. The adsorption abilities of PCs for oxytetracycline (OTC) were compared and the adsorption isotherms of OTC on the optimum sample were studied. Results showed that SW impregnation led to the release of more CO from SD at 700 °C, indicating a higher degree of CO2 activation, thus a 81% higher BET surface area (SBET) can be achieved under the same activation condition. Mesopore volume of PC increased from 0.089 to 0.301 cm3 g−1 with the activation time increasing from 5 to 60 min. PC obtained after 60-min activation with a SBET of 490 m2 g−1 and an average pore diameter of 3.78 nm had the highest adsorption ability for OTC. Its adsorption equilibrium data for OTC followed Langmuir model with a maximum monolayer adsorption capacity up to 100 mg g−1.

Adsorption of oxytetracycline from aquaculture wastewater by modified zeolites: kinetics, isotherm, and thermodynamics

Adsorption of oxytetracycline from aquaculture wastewater by modified zeolites: kinetics, isotherm, and thermodynamics

Amino-functionalized mesoporous silica-magnetic graphene oxide nanocomposites as water-dispersible adsorbents for the removal of the oxytetracycline antibiotic from aqueous solutions: adsorption performance, effects of coexisting ions, and natural organic matter.

The amino-functionalized mesoporous silica-magnetic graphene oxide nanocomposite (A-mGO-Si) was synthesized and used for oxytetracycline (OTC) removal from water. Various factors like the effects of initial concentration, contact time, and influence of pH were investigated. Selective adsorption experiments in connection with coexisting ions and dissolved organic matter (DOM) were also investigated. In this study, humic acid (HA) and tannic acid (TA) were representative of both hydrophobic and hydrophilic DOM, respectively. Results indicated that A-mGO-Si had an adsorption ability for OTC that was relatively greater than that of virgin magnetic graphene oxide (mGO), graphene oxide (GO), Fe3O4 particles, and SBA-15 mesoporous silica and also showed a better uptake removal capacity for OTC at low initial concentration in comparison with the other adsorbents. The adsorption behavior of OTC onto A-mGO-Si could be described by the pseudo-second-order kinetic model and the Freundlich isotherm model. The electrostatic interaction has no influence on the OTC absorbed when the OTC is in an aqueous medium in its zwitterion form (3.22 < pH < 7.46). At high pH, the weak π-π EDA interactions and hydrogen bonding may manifest themselves, hence causing a lower adsorption capacity. The main adsorption mechanisms were plausibly activated by H-bonding, and π-π EDA interactions, while the electrostatic interaction (cation-π interaction) might be the minor adsorption mechanism. Addition of individually exogenous ions (Na+, Mg2+, NO-, and CO32-) resulted in a decrease of OTC adsorption due to the emergence of a competitive effect. Considering the presence of HA and TA in mixed solute systems, the DOM was likely to form a stronger interaction system with mGO-Si, thereby resulting in an adsorption level which was more competitive in the process at low aqueous phase concentration of OTC. In contrast to the high aqueous phase, the coexistence of DOM could promote OTC adsorption. The phenomenon may reflect the result that a surface complexation mechanism could achieve in adsorptions.

Adsorption of oxytetracycline on kaolinite.

As antibiotic contamination increases in wastewater and aqueous environments, the reduction of antibiotics has become a pertinent topic of research regarding water treatment. Clay minerals, such as smectite or kaolinite, are important adsorbents used in water treatment, and sufficient removal of antibiotics by clay minerals is expected. In this study, the adsorption of oxytetracycline (OTC) on kaolinite was investigated. The experimental data of OTC adsorption on kaolinite fit the pseudo-second-order kinetics model well (R2>0.98). After 24 h, adsorption equilibrium of OTC on kaolinite was reached. The Langmuir model was better fitting with the adsorption isotherms generated from experimental data and OTC adsorption occurred on the external surface of kaolinite. The analysis of several thermodynamic parameters indicated that the adsorption of OTC on kaolinite was spontaneous and thermodynamically favorable. With the increase of the pH of a solution, the adsorption capacity increased and then decreased. The adsorption coefficient (Kd) of 102-103 were obtained for adsorption process of OTC on kaolinite.

Hydrothermal synthesis of structurally variable binary CuAl, MnAl and ternary CuMnAl hydroxides for oxytetracycline antibiotic adsorption

Pharmaceuticals are emerging pollutants present mainly in industrial and municipal wastewater. Herein, structurally variable binary and ternary metal hydroxides based on copper, manganese, and aluminum were used for the adsorptive scavenging of the oxytetracycline (OTC) antibiotic. A facile hydrothermal method was used for the synthesis of binary CuAl-hydroxide, MnAl-hydroxide, and ternary CuMnAl-hydroxide. Structural and morphological characteristics of the metal hydroxides (MHs) were studied by X-ray diffraction (XRD), Fourier transformed infrared spectrum (FTIR), X-ray photoelectron spectroscopy (XPS) and Scanning electron microscopy (SEM) analysis. The adsorptive removal for OTC was found in the order CuMnAl-hydroxide > CuAl-hydroxide > MnAl-hydroxide. The highest removal of OTC by CuMnAl-hydroxide and CuAl-hydroxide was observed at pH 7 while MnAl-hydroxide showed the optimum adsorption at pH 9. All three materials showed different saturation time and equilibrium concentration for OTC adsorption. The mechanism investigation found that strong electrostatic attraction, hydrogen bonding, and anion exchange were mainly responsible for the removal of the OTC and adsorption process followed the pseudo-second-order kinetic model and equilibrium data was best fitted to the Langmuir isotherm model. The adsorption of OTC was influenced by the presence of Cu (II) and Cr (VI) ions in the aqueous solution due to the competitive adsorption of co-ions. Moreover, the adsorption of OTC was endothermic in nature, and maximum adsorption capacity was found to be 250.07 mg/g at 50 °C.

Halloysite nanoclay supported adsorptive removal of oxytetracycline antibiotic from aqueous media

Halloysite nanoclay was utilized to retain aqueous oxytetracycline (OTC) which is extensively used in the veterinary industry. The micro-structure and functionality of the nanoclay were characterized through spectroscopic techniques before and after adsorption. The OTC removal experiments were performed at different pH conditions (pH 3.0–9.0), ionic strengths (0.001, 0.01, 0.1 M NaNO3) and contact time (up to 32 h) at an initial 25 mg/L OTC concentration with 1.0 g/L halloysite. Oxytetracycline adsorption was pH dependent, and the best pH was observed in the range of pH 3.5–5.5 at a 0.001 M ionic strength. At pH 3.5, the maximum OTC adsorption amount was 21 mg/g which translated to 68% removal of the initial OTC loading. Positively charged inner lumen and negatively charged outer lumen of the tubular halloysite structure led to form inner-sphere complexes with the anionic and cationic forms of OTC, respectively. A rapid adsorption of OTC was observed in the kinetic study where 62% OTC was adsorbed in 90 min.. Pseudo-second order equation obeyed by the kinetic data indicated that the adsorption was governed by chemisorption, whereas Hill isotherm equation was the most fitted with a maximum adsorption capacity of 52.4 mg/g indicating a cooperative adsorption phenomenon.

Adsorption properties and mechanism of sepiolite modified by anionic and cationic surfactants on oxytetracycline from aqueous solutions

In this study, cetyl trimethylammonium bromide (CTAB) (cationic) and sodium dodecyl benzene sulfonate (SDBS) (anionic) were used to modify natural sepiolite (SEP) to obtain a type of organic sepiolite (C-S-SEP). It was further applied for adsorption of oxytetracycline (OTC), a common antibiotic in water. The changes of SEP crystal structure and physicochemical properties before and after modification were analyzed by the means of XRD, FTIR, TG, SEM/EDS, BET, XPS and zeta potential. The adsorption performance and mechanism of OTC on C-S-SEP were studied by static adsorption method. The results showed that the adsorption capacity of C-S-SEP increased significantly, and the removal rate of OTC increased from 50.26% to 99.42%. The partition coefficient of SEP and C-S-SEP was 0.356 and 2.172 mg g−1 μM−1, respectively. CTAB and SDBS were successfully loaded onto the surface of SEP without entering its interlaminar domain, and the original crystal structure of SEP was well maintained. In the range of the studied ratio, anionic and cationic surfactants had the synergistic solubilization effect. The adsorption process conformed to the pseudo-second-order kinetic model and Langmuir isothermal adsorption model. The adsorption reaction was exothermic and a process of entropy reduction. The increase of temperature was not conducive to adsorption, and the adsorption reaction was basically unaffected by the pH value. The adsorption of C-S-SEP on OTC was the result of the combination of distribution and surface adsorption. The organic modified SEP was expected to become a low-cost environmentally friendly adsorption material that can effectively remove OTC from water.

Kinetics and isotherms of oxytetracycline adsorption on β‐cyclodextrin/carboxymethylcellulose hydrogel films

Oxytetracycline (OTC), widely used as an antibiotic substance in aquaculture, has an adverse effect on environmental and public health. The aim of this paper was to demonstrate that OTC can be removed by hydrogel films composed of β-cyclodextrin/carboxymethylcellulose (β-CD/CMC) with esterification-crosslink method. Oxytetracycline adsorption experiments were performed with an initial pH of 1–12 and an initial concentration of 10–500 mg/L. The experimental data were fitted with Langmuir and Freundlich isotherms and compared using linear and nonlinear models. The experimental results indicate that OTC's adsorption capacity depends on the active β-cyclodextrin content. The optimal pH was around 8.

Efficient removal of oxytetracycline from aqueous solution using magnetic montmorillonite-biochar composite prepared by one step pyrolysis

Three adsorbents, namely, original biochar (CLB), montmorillonite (MMT)-biochar composite (MBC), and magnetic MMT-biochar composite (MMBC) were successfully fabricated by one step pyrolysis of original cauliflower (Brassica oleracea L.) leaves, mixture of cauliflower leaves and MMT, and FeCl3-laden mixture of cauliflower leaves and MMT under limited oxygen atmosphere, respectively. The characterizations of samples indicated that substantial MMT mineral particles and Fe3O4 nanoparticle were dispersed on the surface of MMBC. Due to the introduction of Fe3O4, MMBC performed excellent magnetization property. The adsorption experiments of oxytetracycline (OTC) indicated that the maximum adsorption ability of MMBC was 58.85 mg·g−1, which was 2.63 times as large as CLB, also, larger than that of MBC. Meanwhile, pH, ionic strength, and humic acid (HA) performed slight effects for adsorption of OTC on MMBC. In addition, MMBC still removed 92% OTC after five regeneration cycles. Finally, primary mechanisms of OTC adsorption onto MMBC were attributed to hydrogen bonding and π-π reaction, and ion exchange reaction was considered to exist. Meanwhile, functional groups including Si-O-Al, Si-O-Si, Si-O, and Fe3O4 nanoparticles would provide extra binding sites for OTC adsorption. Therefore, MMBC had an obvious potential to apply into water purification as a reliable, low-cost, and environmentally friendly adsorbent.

Continuous flow electrosorption-microbial fuel cell system for efficient removal of oxytetracycline without external electrical supply

The removal of antibiotics from wastewater has attracted much attention. In this research, an intimately coupled autarkical electrosorption (ES)-microbial fuel cell (MFC) system was developed for real-time removal of the antibiotic oxytetracycline (OTC) from wastewater. The removal efficiency was founded to be up to 98.8% at an OTC concentration of 2 mg/L with 3 g/L sodium acetate (NaAC) as co-substrate and 3 MFCs as power supply. The removal efficiencies increased in the ES unit and decreased in the MFC unit with increasing treating time. The adsorption of OTC on activated carbon fibers (ACFs) in the ES unit proceeds via chemical adsorption resulting from electrostatic attraction and cation exchange. The OTC degradation pathways in the MFC unit were proposed by identifying the intermediates with HPLC-MS/MS. The ACFs in the ES unit were proven to be recyclable and the coupled ES-MFC system is applicable for the removal of antibiotics from wastewater.

Corn stover–derived biochar for efficient adsorption of oxytetracycline from wastewater

Abstract