Initial Ciprofloxacin Concentration Research Articles

Optimization of Visible-Light-Driven Ciprofloxacin Degradation Using a Z-Scheme Semiconductor MgFe2O4/UiO-67.

A heterogeneous photocatalyst, MgFe2O4/UiO-67 (MU-x), was successfully synthesized by doping magnetic magnesium ferrite nanoparticles (MgFe2O4) with the UiO-67 metal-organic framework at various weight ratios (MgFe2O4: UiO-67 at 30, 50, 70, and 90 wt %). Various techniques, including X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR) , Brunauer-Emmett-Teller (BET), photoluminescence (PL), vibrating sample magnetometry (VSM), electrochemical impedance spectroscopy (EIS), and ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS), were used to characterize the prepared photocatalysts. The photocatalytic performance of MU-x in the degradation of ciprofloxacin (CIP) under visible light was assessed. The CIP degradation efficiency was found to increase as the amount of MgFe2O4 in the composite was increased up to 70 wt %. Experimental conditions were optimized using response surface methodology (RSM) based on central composite design (CCD) with three factors: initial pH, catalyst loading, and CIP concentration. Using the obtained model, the optimal conditions were determined as follows: initial pH of 8.025, catalyst loading of 33.8 wt %, and CIP concentration of 10.8 mg/L. Under these optimal conditions, a notable improvement was achieved, with 99.62% of CIP removal achieved within 90 min, surpassing the performance of previously reported photocatalysts. Total organic carbon (TOC) analysis revealed a high degree of mineralization, at 81.25%. The degradation pathway of CIP was investigated based on liquid chromatography-mass spectrometry (LC-MS) analysis. Finally, the values of ECB and EVB of the photocatalyst were determined and the possible degradation mechanism of CIP was investigated based on Mott-Schottky and the applied scavengers. The hydroxyl radical (•OH) was identified as the dominant species in the removal of CIP through a trapping experiment. The photocatalyst with 70 wt % of MgFe2O4 (MU-70) exhibited excellent stability and recoverability with an external magnet, demonstrating 86.33% CIP removal after four cycles. According to the obtained results, MU-70 is a promising visible-light-active photocatalyst with great potential for water treatment applications and convenient recovery.

Removal of Ciprofloxacin Antibiotic from Synthesized Aqueous Solution Using Three Different Metals Nanoparticles Synthesized Through the Green Method

This study investigates the possibility of removing ciprofloxacin (CIP) using three types of adsorbent based on green-prepared iron nanoparticles (Fe.NPs), copper nanoparticles (Cu. NPS), and silver nanoparticles (Ag. NPS) from synthesized aqueous solution. They were characterized using different analysis methods. According to the characterization findings, each prepared NPs has the shape of a sphere and with ranges in sizes from of 85, 47, and 32 nanometers and a surface area of 2.1913, 1.6562, and 1.2387 m2/g for Fe.NPs, Cu.NPs and Ag.NPs, respectively. The effects of various parameters such as pH, initial CIP concentration, temperature, NPs dosage, and time on CIP removal were investigated through batch experiments. The results showed that 10 mg/L CIP was removed by 100%, 92% and 79% within 180 min using Fe.NPs, Cu.NPs, and Ag.NPs respectively. In addition to this, kinetic models of the adsorption and mechanism of CIP removal were studied. The cinematic analysis demonstrated that adsorption is a physics adsorption mechanism with an energy of 0.846 kJ.mol-1, 1.720 kJ.mol-1, and 3.872 kJ.mol-1, while the low activation energies of 17.660 kJ.mol-1, 13.221 kJ.mol-1, and 14.060 kJ.mol-1 for Fe.NPs, Cu.NPs, and Ag.NPs respectively. The kinetic removal process follows a pseudo-first-order model following a physical diffusion-controlled reaction. The data on adsorption was analyzed using the Langmuir, Freundlich, Temkin, and Dubinin models, as well as thermodynamic factors, indicating that the process is appropriate and endothermic sorption. The most practical adsorbent was Fe.NPs

Optimization of the removal of the antibiotic ciprofloxacin by composite aerogels based on PVA/agar/maltodextrin

In this study, we used a synthetic aerogel based on PVA/agar/maltodextrin to remove the antibiotic ciprofloxacin (CFX) from aqueous media. Response surface method (RSM) is used to study the relationship between the factors affecting the adsorption process, thereby optimizing the adsorption efficiency, and making decisions on improving the adsorption process better sub. The research results obtained are as follows: pH2, initial CFX concentration 51 mg L−1, adsorbent dosage 0.16 g L−1, adsorption time 120 min, and temperature 51.5 °C reached the maximum adsorption capacity. The maximum additive is 38.63 mg g−1. The experimental data agree with the pseudo-quadratic kinetic model and the Langmuir and Temkin isotherm models. The composite aerogel adsorbent (AE) in this study is a potential candidate for adsorbent to remove antibiotic contamination in aqueous media.

CuCoFe2O4@AC magnetic nanocomposite as a novel heterogeneous Fenton-like nanocatalyst for Ciprofloxacin degradation from aqueous solutions

CuCoFe2O4@Activated Carbon (AC) was synthesized by a fast, simple, and green microwave-assisted coprecipitation method, and then used as a new heterogeneous magnetic nanocatalyst in Fenton-like reaction for ciprofloxacin (CIP) degradation from aqueous media. CuCoFe2O4@AC was characterized by Field emission scanning electron microscopy (FE-SEM), Energy-Dispersive Spectroscopy (EDS), Mapping, Line scan, Fourier-transform infrared spectroscopy (FT-IR), Thermal gravimetric analysis (TGA), X-Ray diffraction analysis (XRD), vibrating-sample magnetometer (VSM), and Brunauer–Emmett–Teller (BET) techniques. The characterization results showed that the CuCoFe2O4@AC nanocomposite was in the ferrite phase with a mesoporous, uniform, quasi-spherical surface and a particle size of about 25 nm. The total volume of single-point adsorption pores was equal to 0.22 cm3 g−1 and the specific surface area was determined to be 199.54 m2 g−1. This nanocomposite had good thermal stability with high magnetic strength. In the presence of H2O2, the synthesized nanocomposite provided a Fenton-like reaction for CIP removal from aqueous solutions. The investigation of this process showed that neutral pH, 1 g L−1 of the nanocomposite, and 73.5 mM of H2O2 were the optimal conditions for CIP removal with an initial CIP concentration of 20 mg L−1. The maximum removal efficiency of 95.77% was attained after 120 min of contact time under the optimum conditions. The CIP degradation during this Fenton-like process followed a pseudo-first-order kinetic model with rate constants (Kapp) of 0.01 min−1. Finally, the CIP removal efficiency after 5 cycles of recovery and regeneration of CuFe2O4@AC was 87.65%. The excellent performance and high catalytic activity of CuCoFe2O4@AC in Fenton-like reaction for CIP removal make it have potential application foreground in the treatment of pharmaceutical wastewater.

Synthesis of a novel HoFeO3/Ho3Fe5O12 nanoadsorbent for efficient absorption of ciprofloxacin from liquid-phase: Modeling and optimization using response surface methodology

In this research, a new magnetic nano adsorbent was prepared for the absorption of the ciprofloxacin antibiotic from aqueous media. Also, some parameters affecting the absorption such as time, pH, the concentration of ciprofloxacin, and the nano adsorbent dose, were investigated. A response surface methodology (RSM) based on a central composite design (CCD) was used to determine the optimum points in the ciprofloxacin adsorption and create a valid mathematical model to predict the absorption of ciprofloxacin by the new nano adsorbent. The structure and morphological properties of the synthesized adsorbent were characterized by some special analysis. After determining the optimal points, the kinetics, isotherm and the recovery rate of the adsorbent were also investigated. The results showed that the quadratic model described the best adsorption of ciprofloxacin onto nano adsorbent, and the R2, adjusted R2, and predicted R2 were 0.9867, 0.9808, and 0.9622, respectively. Under optimized conditions (time 45 min, adsorbent dosage 700 mg/L, pH 5, initial ciprofloxacin concentration 25 mg/L), the removal efficiency with a desirability factor of 1 was 91.50 %, and the predicted one was 90.49%. Also, the process follows the quadratic model and the Langmuir isotherm. The recovery results determined that the absorption rate after 5 consecutive cycles is still close to 80%. Therefore, it can be concluded that the new nano adsorbent can be an efficient adsorbent in removing ciprofloxacin from aquatic environments.

Antibiotic ciprofloxacin removal from aqueous solutions by electrochemically activated persulfate process: Optimization, degradation pathways, and toxicology assessment

Ciprofloxacin (CIP) is a commonly used antibiotic in the fluoroquinolone group and is widely used in medical and veterinary medicine disciplines to treat bacterial infections. When CIP is discharged into the sewage system, it cannot be removed by a conventional wastewater treatment plant because of its recalcitrant characteristics. In this study, boron-doped diamond anode and persulfate were used to degrade CIP in an aquatic solution by creating an electrochemically activated persulfate (EAP) process. Iron was added to the system as a coactivator and the process was called EAP+Fe. The effects of independent variables, including pH, Fe2+, persulfate concentration, and electrolysis time on the system were optimized using the response surface methodology. The results showed that the EAP+Fe process removed 94% of CIP under the following optimum conditions: A pH of 3, persulfate/Fe2+ concentration of 0.4 mmol/L, initial CIP concentration 30 mg/L, and electrolysis time of 12.64 min. CIP removal efficiency was increased from 65.10% to 94.35% by adding Fe2+ as a transition metal. CIP degradation products, 7 pathways, and 78 intermediates of CIP were studied, and three of those intermediates (m/z 298, 498, and 505) were reported. The toxicological analysis based on toxicity estimation software results indicated that some degradation products of CIP were toxic to targeted animals, including fathead minnow, Daphnia magna, Tetrahymena pyriformis, and rats. The optimum operation costs were similar in EAP and EAP+Fe processes, approximately 0.54 €/m3.

Preparation of sodium alginate gel microspheres catalysts and its high catalytic performance for treatment of ciprofloxacin wastewater

The discharge of the antibiotic wastewater has increased dramatically in our country with the development of medical science and wide application of antibiotic, resulting in serious harm to human body and ecological environment. In this work, ciprofloxacin (CIP) was selected as one of typical antibiotics and heterogeneous Fenton-like catalysts were prepared for the treatment of ciprofloxacin wastewater. The sodium alginate (SA) gel microspheres catalysts were prepared by polymerization method using double metal ions of Fe3+ and Mn2+ as cross-linking agents. Preparation conditions such as metal ions concentration, mass fraction of SA, polymerization temperature and dual-metal ions as crosslinking agent were optimized. Moreover, the effects of operating conditions such as initial concentration of CIP, pH value and catalyst dosage on CIP removal were studied. The kinetic equation showed that the effect of the initial concentration of CIP on the degradation rate was in line with second-order kinetics, and the effects of catalyst dosage and pH value on the degradation rate of CIP were in line with first-order kinetics. The SA gel microspheres catalysts prepared by dual-metal ions exhibited a high CIP removal and showed a good reusability after six recycles. The SA gel microspheres catalysts with an easy recovery performance provided an economical and efficient method for the removal of antibiotics in the future.

Enhanced visible-light-responsive photodegradation of ciprofloxacin by direct Z-scheme ZnFe2O4@g-C3N4 nanocomposites

The zinc ferrite@graphitic carbon nitride (ZnFe2O4@g-C3N4, ZFO@CN) nanocomposites were fabricated as the direct Z-scheme heterostructured photocatalysts for the enhanced visible-light-driven photodegradation of ciprofloxacin (CIP). The 15 – 30 nm ZFO, fabricated from the nonaqueous hydrothermal method, is well-distributed on the sheet-like CN structure, resulting in the high specific surface and mesoporosity with increased surface-to-volume ratio and reactive sites. Moreover, the heterojunction interface between ZFO and CN enhances the visible light response as well as decreases the electron–hole recombination, and subsequently increases the photodegradation performance of CIP over ZFO@CN. A nearly complete removal efficiency with a rate constant of 0.047 min−1 for CIP photodegradation is observed. The environmental parameters including pH, initial CIP concentration, inorganic anions and water matrices were examined to optimize the photocatalytic activity of the ZFO@CN nanocomposite. The ZFO@CN nanocomposite exhibits excellent structural and physicochemical stability and good reusability over 5 cycles. The radical trapping results signify that O2− and h+ are the primarily responsible radicals for the enhanced degradation of CIP over direct Z-scheme ZFO@CN heterojunction. Results clearly elaborate on the superiority of ZFO@CN over the photodegradation of CIP, which can serve as the platform for the fabrication of metal oxide@CN as the Z-scheme heterojunction for water and wastewater purification.

A novel chitosan-coated Fe–Cu CNS loaded with CMC–Alginate composite for adsorptive removal of ciprofloxacin from water

Indiscriminate usage of antibiotic, Ciprofloxacin (CIPRO) poses a serious environmental threat by accumulating in the water bodies. A novel clay-nanosheet supported with Fe-Cu nanocomposite was developed for CIPRO removal using an eco-friendly approach. This composite was immobilised in a biodegradable chitosan-coated Alginate-CMC matrix to form nanocomposite beads for ease of usage in the column reactors. About 90% CIPRO removal was attained through batch mode under optimal conditions (20 mg/L CIPRO; bead loading 2000 mg/L; bead weight 0.15 g; contact period 300 min; and pH - 6). Effect of various environmental factors such as salts NaCl and CaCl2 (0.05, 0.1, 0.2, 0.5 and 1 M), and micro contaminants humic acid and polyethylene (1, 2, 3, 4 and 5 M) on CIPRO adsorption by NC beads was studied. Pseudo-second order kinetics was observed by the removal process and Langmuir isotherm by the adsorption with a maximum removal capacity of 485.58 mg/g. The effects of various reaction parameters such as the flow rate (1, 2 and 3 mL/min), initial CIPRO concentration (20, 40 and 60 mg/L) and bed height (3, 5 and 7 cm) were studied in the column reactors. The residual toxicity of composite beads interacted CIPRO solution was analysed with environmentally relevant algae such as Chlorella sp. and Scenedesmus obliquus, and the studies confirmed significant reduction in their toxic effects.

Important effects of polypropylene on migration of ciprofloxacin in groundwater

To investigate the effect of microplastics on the transport and retention of antibiotics in subsurface environment, polypropylene (PP) and ciprofloxacin (CIP) are selected as typical microplastic and antibiotic contaminant, respectively. The key factors and main control mechanisms are systematically investigated using a combination of adsorption experiments, column experiments and numerical model. The adsorption experiments indicate the largest adsorption capacity of CIP on PP is 1.03 mg·g−1. Simultaneously, the results of column experiments and numerical model suggest that PP can significantly affect the migration behavior and retention of CIP in porous media. CIP mobility is positively correlated to flow velocity, initial concentration of CIP and ionic strength (Na+, Ca2+ and Ba2+). Moreover, compared to monovalent cation (Na+), divalent cations (Ca2+, Ba2+) have a stronger enhancement effect on CIP mobility and a stronger inhibition effect on CIP retention in saturated porous media. The transport of CIP in saturated porous media containing PP is simulated by a single-point kinetic model, and the equations of the transport kinetic parameters of CIP are obtained through regression analysis. The research could help to gain insight into understanding the environmental behavior of antibiotic in the groundwater system, and provide scientific basis for the accurate prediction and assessment of environmental risk caused by microplastic and antibiotic in the groundwater system.

Degradation of Ciprofloxacin (CIP) Antibiotic Waste using The Advanced Oxidation Process (AOP) Method with Ferrate (VI) from Extreme Base Electrosynthesis

Ciprofloxacin (CIP) antibiotic liquid waste is the most common waste found in hospital discharge waters. The accumulation of CIP can increase mutation, microbial resistance, and toxicity in the environment due to its low biodegradability and longevity in waters. Thus, methods for eliminating CIP are important. The Advanced Oxidation Process (AOP) method with ferrate (VI) has good redox potential in water disinfection, and degradation of organic and inorganic pollutants. Therefore, this study aims to degrade CIP waste with ferrate (VI). The ferrate (VI) used was synthesized from the electrolysis of transformer scrap metal plates under extremely alkaline conditions. The success of the synthesis was proven by the presence of FeO(OH) groups characterized using FTIR, XRF, and XRD. Then, the effect of time, pH, and CIP degradation was studied. The results showed that the maximum performance was obtained at pH 7 and 120 min with the addition of 1.1 mg ferrate at initial CIP concentration of 30 mg/L. The concentration of CIP decreased with increasing treatment time which was confirmed by UV-Vis Spectrophotometer. This condition is able to degrade 86.7 % of CIP. In addition, the LC-MS results show that degradation occurs due to a reaction between HFeO4-/H2FeO4 and the active site of piperazine ring antibiotics. This shows that Ferrate has a promising potential to reduce ciprofloxacin antibiotic pollution from hospital wastewater for a better environment. HIGHLIGHTS Ciprofloxacin (CIP) antibiotic liquid waste is the most common waste found in hospital discharge waters. It can cause mutation, microbial resistance, and toxicity in the environment due to its low biodegradability and longevity in waters The Advanced Oxidation Process (AOP) method with ferrate (VI) has good redox potential in water disinfection, and degradation of organic and inorganic pollutants including antibiotic liquid waste Ferrate was able to degrade 86.7 % of ciprofloxacin antibiotic pollution from hospital wastewater through a reaction between HFeO4-/H2FeO4 and the active site of piperazine ring antibiotics GRAPHICAL ABSTRACT

Waste-Based Ceramsite for the Efficient Removal of Ciprofloxacin in Aqueous Solutions

Ciprofloxacin (CIP), a compound with bioaccumulation toxicity and antibiotic resistance, is frequently detected in water at alarming concentrations, which is becoming an increasing concern. In this study, a low-cost ceramsite was developed from industrial solid wastes through sintering to remove CIP from wastewater. The effects of adsorbent dosage, initial pH, contact time, initial CIP concentration, and temperature were explored. More than 99% of CIP (20-60 mg/L) was removed at around pH 2-4 by the ceramsite. The kinetic data fitted well with the pseudo-second-order model, revealing that chemisorption was the main rate-determining step. The isotherm data was better described by the Freundlich model, suggesting that CIP was removed by the formation of multiple layers on the heterogeneous surface. Moreover, the removal efficiency was practically higher than 95% during five regeneration cycles, when different regeneration methods were used, including calcination, HCl, and NaOH washing, indicating that the ceramsite exhibited outstanding reusability in removing CIP. The primary mechanism of CIP removal by the ceramsite was found to be the synergism of adsorption and flocculation, both of which depended on the release of Ca2+ from the ceramsite. In addition, strong Ca-CIP complexes could be formed through surface complexation and metal cation bridging between Ca2+ and different functional groups in CIP.

Optimization of Ciprofloxacin Adsorption on Clinoptilolite-Based Adsorbents Using Response Surface Methodology.

The adsorption of the antibiotic ciprofloxacin (CIP) from water solution by natural zeolite-clinoptilolite (CLI), magnetic clinoptilolite (MAG-CLI), and graphene oxide coated magnetic clinoptilolite (GO-MAG-CLI) was investigated. The novel approach of an environmentally friendly and cost-effective microwave-assisted method was applied for the magnetic composite synthesis. Detailed characterization of the prepared composites was achieved. In order to investigate the effect of the initial CIP concentration, pH, temperature, contact time, and type of adsorbent on the adsorption efficiency of CIP, and to obtain the optimal conditions for CIP removal, the response surface methodology central composite factorial design (RSM-CCF) was applied. The results obtained by the RSM-CCF showed that among the studied adsorbents, GO-MAG-CLI had the highest adsorption capacity for CIP, achieved for the initial concentration of 48.47 mg dm-3 at a pH of 5 and 24.78 °C after 19.20 min of contact time. The adsorption kinetics studied for the initial CIP concentration range of 15-50 mg dm-3 followed Lagergren's pseudo-second-order model, and the Langmuir isotherm was the most suitable one to describe the CIP adsorption onto GO-MAG-CLI.

Complete Elimination of the Ciprofloxacin Antibiotic from Water by the Combination of Adsorption–Photocatalysis Process Using Natural Hydroxyapatite and TiO2

The main objective of this work was to assess the performance of combined processes, adsorption/ photodegradation of the ciprofloxacin antibiotic (CIP). Adsorption was achieved on natural hydroxyapatite (nat-HA) in the batch mode. The effect of pH (3–12), initial ciprofloxacin concentration (C0, 25–200 mg L−1), adsorbent dose (m, 0.25–3 g L−1), and temperature (T, 298–328 K) on the ciprofloxacin adsorption capacity was studied. At 298 K, the maximum uptake of 147.7 mg g−1 was observed with pH close to 8, 1 g L−1nat-HA dose, and 150 mg L−1 initial CIP concentration. Adsorption was effective, with a removal percentage of 82% within 90 minutes of contact time. For ciprofloxacin adsorption onto nat-HA, a pseudo-second-order kinetic model is well-suited. The Langmuir isotherm model successfully fit the experimental data and the process was spontaneous and exothermic. The coupling processes (adsorption/photocatalysis) were examined and found to be highly effective. For the remaining concentrations, the maximum degradation efficiency and mineralization yield were ~100% and 98.5%, respectively, for 1 mg L−1 initial CIP. The combination of the strong adsorption capacity of natural hydroxyapatite and the high photocatalytic activity of TiO2 can be an effective technique for removing fluoroquinolone antibiotics from wastewater.

PVA-assisted CNCs/SiO2 composite aerogel for efficient sorption of ciprofloxacin.

Efforts to develop a green, inexpensive and effective adsorbent are crucial for eliminating antibiotics in polluted water. The sorption capacity of the as-prepared polyvinyl alcohol (PVA)-assisted cellulose nanocrystals/SiO2 (CNCs/SiO2) composite aerogel to ciprofloxacin (CIP) rises with the increase of temperature and initial concentration. Reverse trend of sorption capacity can be found when increasing the adsorbent dosage of adsorbent. The optimal pH value for the sorption is proved to be 4. It's found in the uniaxial compression test that the maximum load that PVA-assisted aerogels can withstand is nearly 100 times than that of non-PVA aerogels. Sorption results confirm that the Pseudo-second order (R2=0.9885) and Langmuir models (R2=0.9959) fit well to sorption kinetics and equilibrium data, respectively. The rate constant differs from the initial concentration of CIP according to the Pseudo-second order model. The composite aerogel sorption capacity of Langmuir (qmax) for CIP was 163.34mg·g-1. The thermodynamic studies showed that the sorption process is endothermic with the value of enthalpy change of 41.032kJ/mol. Hydrogen bonding, π-π interaction, hydrophobic and electrostatic interactions are the dominant mechanisms of CIP sorption by the PVA-assisted CNCs/SiO2 composite aerogel.

Efficient Removal of Ciprofloxacin from Contaminated Water via Polystyrene Anion Exchange Resin with Nanoconfined Zero-Valent Iron.

Ciprofloxacin (CIP), an important emerging contaminant, has been frequently detected in water, and its efficient removal has become an issue of great concern. In this study, a nanocomposite material nZVI/PA was synthesized by impregnating nanoscale zero-valent iron (nZVI) inside a millimeter-sized porous host (polystyrene-based anion exchange resin (PA)) for CIP removal. The nZVI/PA composite was characterized by field emission scanning electron microscopy coupled with energy-dispersive X-ray, transmission electron microscopy, X-ray diffraction, as well as X-ray photoelectron spectroscopy, and it was confirmed that nZVI was uniformly dispersed in PA with a small particle size. Furthermore, several key factors were investigated including initial solution pH, initial CIP concentration, co-existing ions, organic ligands, and dissolved oxygen. The experimental results indicated that the nZVI/PA composites exhibited a high removal efficiency for CIP under the conditions of initial pH 5.0, and initial CIP concentration 50 mg L-1 at 25 °C, with the maximum removal rate of CIP reaching 98.5%. Moreover, the nZVI/PA composites exhibited high efficiency even after five cycles. Furthermore, quenching tests and electron spin resonance (ESR) confirmed that CIP degradation was attributed to hydroxyl (·OH) and superoxide radicals (⋅O2-). Finally, the main degradation products of CIP were analyzed, and degradation pathways including the hydroxylation of the quinolone ring, the cleavage of the piperazine ring, and defluorination were proposed. These results are valuable for evaluating the practical application of nZVI/PA composites for the removal of CIP and other fluoroquinolone antibiotics.

Semiconductor Synthesis and Application for the Treatment of Ciprofloxacin Antibiotic by Solar Heterogeneous Phocatalysis

The objective of this study is to examine the relevance of treatment with the antibiotic ciprofloxacin by heterogeneous solar photocatalysis. The efficiency of the catalyst (ZnO) synthesized by the precipitation method is also determined. The solid- visible UV analysis showed that the spectrum reveals an absorption peak at 364 nm, which can be attributed to the band gap with of ZnO, in the case of the electron transition from the band of valence towards the conduction band (2p 3d) [3] and [4]. Under optimal conditions, initial ciprofloxacin concentration 10 ppm, ZnO dose 0.1 g/L and free pH (6) ; treatment by solar photocatalysis in the presence of ZnO showed a ciprofloxacin elimination yield of 87% is obtained after 240 min of treatment. The total degradation of ciprofloxacin is observed, by the disappearance of the ciprofloxacin absorption peak during the treatment time. Analysis by infrared spectroscopy showed that only two groups are obtained O-H and C=O at 3500 cm-1 and 1600 cm-1, respectively after 240 min of oxidation. The BOD5/COD ratio increased from 0.005 initially to 2.13 after 240 min of ciprofloxacin treatment by solar photocatalysis. The relevance of the solar photocatalytic process is shown. At the end of these results, the relevance of the treatment of ciprofloxacin antibiotic by solar photocatalysis in the presence of the semiconductor ZnO is shown.

Photocatalytic Degradation of Ciprofloxacin by UV Light Using N-Doped TiO2 in Suspension and Coated Forms

The presence of organic compounds such as ciprofloxacin in untreated pharmaceutical wastewater often poses a serious health risk to human and aquatic life when discharged into water bodies. One of the most effective means of removing ciprofloxacin from wastewater is photocatalytic degradation. However, the synthesis of an effective photocatalyst that can degrade the organic pollutant in the wastewater is often a challenge. Hence, this study focuses on the synthesis and application of nitrogen-doped TiO2 (N-TiO2) in suspension and coated forms for the photocatalytic degradation of ciprofloxacin in wastewater by applying UV-light irradiation. The nitrogen-doped TiO2 photocatalyst was prepared by a co-precipitation process and characterized using energy-dispersive X-ray spectroscopy, scanning electron microscopy, and Fourier-transform infrared spectroscopy. The effects of the initial concentration of the ciprofloxacin (6, 12, 18, or 30 ppm), pH (3, 5, 7, or 9), and flow rate (0.4, 0.8, 0.95, or 1.5 L/min) on the degradation of the ciprofloxacin over the N-TiO2 were investigated. The results showed that the removal efficiency of ciprofloxacin was enhanced by increasing the initial ciprofloxacin concentration, while it was decreased with the increase in the feed flow rate. The best operating conditions were obtained using an initial ciprofloxacin concentration of 30 ppm, pH of 5, and feed flow rate of 0.4 L/min. Under these operating conditions, removal efficiencies of 87.87% and 93.6% were obtained for net TiO2 and N-TiO2 of 5 wt% in suspension form, respectively, while 94.5% ciprofloxacin removal efficiency was obtained using coated 5 wt% N-TiO2 after 2 h of photocatalytic degradation. Based on the response surface optimization strategy, a quadratic model was suggested to obtain mathematical expressions to predict the ciprofloxacin removal efficiency under various studied operational parameters.

Ultrasonic Degradation of Ciprofloxacin in the presence of Zinc Oxide Nanoparticles and Zinc Oxide/Acha Waste Composite

In this study, zinc oxide nanoparticles (ZnO-NPs) and zinc oxide nanoparticles/acha waste composite (ZnO-NPs/acha waste) were synthesized via precipitation method to enhance the ultrasonic degradation of ciprofloxacin from aqueous solution. The ZnO-NPs and composite were characterized using Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) and were used for the ultrasonic degradation of ciprofloxacin (CIP) in aqueous solution. The operating parameters such as sonication time (20-60min), ultrasonic amplitude (20-100%), pH (2-10), initial CIP concentration (3.125-50 mg/L) and catalyst dosage (0.02-0.1g) were examined for ultrasound only, ultrasound/ZnO-NPs and ultrasound/ZnO-NPs/acha waste treatment methods. The degradation experiment showed that a maximum degradation of 97.0% was achieved by the ultrasound/ZnO-NPs/acha waste method within 40 min when compared with ultrasound only (39.0%) and the ultrasound/ZnO-NPs method (85.0%). Moreover, the kinetic study indicated that the degradation of CIP with ultrasound catalyzed with ZnO-NPs is 6.5 times faster in comparison to ultrasound only whereas, the use of ultrasound with ZnO-NPs/acha waste is 10.6 times faster. Therefore, the ultrasound/ZnO-NPs/acha waste method has proven to be effective for the removal of pharmaceuticals from wastewater.

Characterization of a flow-through electrochemical reactor for the degradation of ciprofloxacin by photoelectro-Fenton without external oxygen supply

This work reports the experimental characterization of an innovative electrolyzer designed for self-sustained H2O2 production and synchronized degradation of the antibiotic ciprofloxacin (CIP) by photoelectro-Fenton (PEF) process tested in recirculation operation mode. The flow-through electrochemical reactor comprises an arrangement of two alternated anodes and cathodes, using the anodic O2 generated from water oxidation at Ti|IrO2-Ta2O5 anodes to produce H2O2 at graphite-felt cathodes from the oxygen reduction reaction (ORR). The influence of the most relevant operation conditions such as the initial Fe2+ concentration, applied current density, liquid flow rate (Q) and initial CIP concentration was systematically examined during the electrolytic trials by analyzing the CIP concentration decay, solution mineralization, and time course of Fe2+ content. It is demonstrated that the H2O2 concentration attained with this reactor configuration is sufficient to run the PEF treatment without needing an air pump or compressor. Complete elimination of CIP was reached at 40 min, with mineralization current efficiency and electrolytic energy consumption of 42% and 0.25 kWh (g TOC)-1, respectively. Oxalic and oxamic acids were the final organic by-products of the destruction of CIP, which also yielded nitrate, ammonium, and fluoride ions. PEF outperformed other processes like anodic oxidation with cathodic H2O2 and electro-Fenton (EF), as revealed by comparing the degradation and mineralization profiles.