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In this study, Fe-doped TiO 2 nanofilm was fabricated using a solvothermal method and subsequently applied to the substrate via an electrophoretic deposition (EPD) technique without requiring a binding agent. The aim of this research is to enhance the sonophotocatalytic performance of TiO 2 by integrating iron impurities into the catalyst structure, thereby addressing the limitation of the catalyst's inactivity under visible light and tackling the issue of catalyst separation for reuse. This method guarantees that the nanofilm is deposited uniformly and under regulated conditions on the substrate. X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive X-ray (EDX) analysis, Fourier transform infrared spectroscopy (FTIR), and UV–Vis techniques were employed to characterize the synthesized nanofilms. The findings indicate that the resulting nanofilms were responsive to visible light and exhibited high efficiency in the degradation of amoxicillin (AMX). The sonophotocatalytic process eliminated approximately 90 % of the amoxicillin, while ultrasound alone could degrade 17 % and visible light alone could degrade about 39 %. It was calculated and noted that the combination of ultrasonic and visible light had a synergistic effect of roughly 70.7 %. The most notable discovery was that the nanofilm could degrade 83 % of AMX after four applications, demonstrating its reusability. [ABSTRACT FROM AUTHOR]

A One-Step hydrothermal process was applied in this study to synthesize magnetic Fe 3 O 4 /3D graphene/Sesamum indicum nanocomposite (M3DGSN). Acid Red 88 (AR88) was set at the target pollutant to be adsorbed and removed by the synthesized nanocomposite from the aqueous media. Field Emission scanning electron microscopy, Fourier transform infrared spectroscopy, vibrating sample magnetometery, and X-Ray diffraction analyses were applied to characterize the product. Artificial neural network modeling has also been employed in the adsorption process of AR88 using M3DGSN. Adsorption studies were performed in the dye concentration range of 5–30 mg L-1 with the adsorbent weight of 25–100 mg. It was observed that the dye removal efficiency using M3DGSN was dependent on different operational parameters and increased with rising pH, time, and weight of M3DGSN. Also, decreasing the dye concentration demonstrated the enhancement of dye removal efficiency. The optimum adsorbent amount and dye concentrations were observed to be 100 mg and 5 mg L-1, respectively. Also, the optimum removal performance was seen at the pH of 9. [Display omitted] • Magnetic Fe 3 O 4 /3D graphene/sesumum indicum (M3DGSN)) was synthesized successfully using a One-Step hydrothermal process. • M3DGSN proved to be an efficient, inexpensive and non-toxic adsorbent of dye. • The adsorbtion process was successfully optimized using Artificial Neural Network. • FESEM images show the 3D porous structure, facilitated the adsorption in the dye removal process. • Effects of different operating variables were investigated during adsorption. [ABSTRACT FROM AUTHOR]

In the electro-Fenton process, one of the important challenges is to adjust the pH of the environment in the acidic region so that the system's performance is not affected by side reactions. In this case, it will be necessary to neutralize the solution after the process. One of the solutions is to use a heterogeneous catalyst to widen the pH range. However, recovering the used catalyst itself can be another challenge. Modifying the electrode using electroactive materials can answer both of these challenges. This work modified the bare graphite-felt (GF) electrode using zeolitic imidazolate frameworks (ZIF)-derived carbon material doped with Co and Zn through a rapid, room-temperature, and water-based synthesis method. Various analyses, including XRD, SEM, XPS, and LSV, confirmed the proper modification of bare GF carbon fibers. The modified Co/Zn-N-C@GF electrode showed good performance in removing rifampicin (RFP) during the electro-Fenton process, so about 90 % of the pollutant was removed within 30 min without adding a homo-/heterogeneous catalyst. Optimum conditions for this process were 1.0 V for applied voltage, 40 mg/L for initial concentration of RFP, and 5.6 for pH. Also, LC-MS analysis was performed to confirm the degradation of RFP and investigate its degradation pathway. [Display omitted] • XRD/XPS revealed the presence of Co3+, Co2+, and Co0 in the modified GF. • LSV proved that the modified GF has lower overpotential and higher reaction current. • Co/Zn-N-C@GF significantly enhanced kinetics (> 2 times) despite its small size. • The role of ROSs in pollutant degradation was recognized as 1O2 > O2•− > •OH. [ABSTRACT FROM AUTHOR]

Prednisolone (PRD) is a popular synthetic corticosteroid medication that discharging it into wastewater raises potential environmental issues. In terms of treatment methods, advanced oxidation processes (AOPs), such as the electro-Fenton (EF) process, have been proposed as a potential option. This study investigates the removal of PRD from aqueous media using both homogeneous and heterogeneous EF processes. A reduced graphene oxide/Tin (IV) oxide/stainless steel mesh (rGO/SnO 2 /SSm) composite system was prepared as the cathode electrode, and a reduced graphene oxide/magnetite/cotton fabric (rGO/Fe 3 O 4 /CF) composite system was prepared as the heterogeneous catalyst. The optimization of process parameters for each system was carried out using response surface methodology (RSM). The removal efficiencies of PRD were determined under optimal conditions. The homogeneous EF process achieved an 83.79% removal efficiency, while the heterogeneous EF process achieved a 74.62% removal efficiency. The properties of the heterogeneous catalyst and the cathode electrode were investigated using SEM, XRD, FT-IR, CV and EDX analyses. GC-MS and TOC analyses were performed to evaluate degradation intermediates and mineralization efficiency. The stability and reusability of the heterogeneous catalyst and the synthesized cathode electrode were evaluated. These findings offer insightful information about the use of EF methods for PRD removal. [Display omitted] • Prednisolone was removed from water by the electro-Fenton process. • Homogeneous and heterogeneous catalysts were used in the electro-Fenton process. • A new cathode electrode was prepared using stainless steel mesh. • A new heterogeneous catalyst based on cotton fabric was prepared. [ABSTRACT FROM AUTHOR]

Nowadays, the entry of organic compounds into water resources is one of the leading global concerns due to the lack of water resources and rapid population growth. In this research, anodic oxidation (AO) method was used to remove 5-fluorouracil (5-FU) from aqueous solutions via Ni/RuO 2 and Ti/IrO 2 –TiO 2 –RuO 2 electrodes as cathode and anode, respectively. For this purpose, the characterization analysis of the electrodes, including X-ray diffraction, scanning electron microscopy, energy dispersive X-ray, and atomic force microscopy were performed. The electrochemical performance of the anode was investigated via cyclic voltammetry analysis. Then, the effect of operational variables, including applied current (mA), initial pH of the solution, initial 5-FU concentration (mg/L), and process time (min) on the 5-FU removal efficiency under the AO process was evaluated via artificial neural network (ANN) modeling. The results revealed that the maximum 5-FU removal efficiency was 96.96%. The applied current intensity, pH, initial 5-FU concentration, and process time were 300 mA, 5, 20 mg/L, and 140 min, respectively. Moreover, the investigation of 5-FU removal by-products and mineralization efficiency of the AO process was carried out via gas chromatography-mass spectrometry and total organic carbon analysis, respectively. The total organic carbon mineralization efficiency was 84.80% after 6 h of reaction time. The reusability and stability of the Ti/IrO 2 –TiO 2 –RuO 2 anode on 5-FU removal efficiency were measured and showed an approximately 5% decay in 5-FU removal efficiency after eight consecutive runs. The overall results and analysis confirmed this method is capable of removing 5-FU through Ti/IrO 2 –TiO 2 –RuO 2 anode and Ni/RuO 2 cathode from aqueous medium. [Display omitted] • Anodic oxidation was applied to investigate 5-fluorouracil (5-FU) removal. • 5-FU removal efficiency was predicted by artificial neural network modeling. • 96.96% of 5-FU removal was achieved via Ti/Ir 0·2 Ti 0·6 Ru 0·2 O 2 and Ni/RuO 2 electrodes. • Anodic oxidation process possible by-products was identified via GC-MS. • The electrodes showed great performance of reusability after eight runs. [ABSTRACT FROM AUTHOR]

Abstract: The peroxi-coagulation process has been used for treatment of aqueous solutions of four dyes with different structures, namely C.I. Basic blue 3 (BB3), Malachite green (MG), C.I. Basic red 46 (BR46) and C.I. Basic Yellow 2 (BY2) at pH 3.0. The experiments were conducted using an open, undivided and cylindrical glass cell in the presence of sulfate electrolyte media with a carbon nanotube–polytetrafluoroethylene (CNT–PTFE) electrode as cathode. Outer and inside diameters of used carbon nanotube were 8–15nm and 3–5nm, respectively. Up to 90% decolorization of each of the dyes occurred in less than 10min. BY2 has been used as a model among the dyes to study the effect of operational parameters, modeling of process by artificial neural networks (ANN) and calculating operation costs. TOC measurements of the BY2 and mixed dyes showed 92% and 93% decontamination at 6h, respectively. Relationship between the predicted results of the designed ANN model and the experimental data was also conducted. The ANN model yielded a determination coefficient of R 2 =0.989 and could describe the decolorization efficiency under different conditions. Our results also showed that the peroxi-coagulation process with CNT–PTFE electrode as cathode could removal 95% and 90% of BY2 and mixed dyes in 40min from a real wastewater. The operation cost for decolorization of the dye solution containing BY2 was calculated (≈21.7 US$ (kgdye removed)−1). [Copyright &y& Elsevier]

Abstract: The electrochemical treatment of solutions containing C.I. Basic Yellow 2 (BY2) in aqueous solutions with carbon-PTFE (polytetrafluoroethylene) and carbon nanotube (CNT)-PTFE electrodes as cathode has been studied. The fabricated electrodes were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The amount of electrogenerated H2O2 on the surface of these electrodes was investigated, too. The results showed that the amount of H2O2 obtained with the CNT-PTFE electrode was nearly three times higher than that of carbon-PTFE electrode. The decolorization efficiency of BY2 in peroxi-coagulation process reached 62% and 96% in the first 10min by carbon-PTFE and CNT-PTFE electrodes at 100mA, respectively. The effect of operational parameters such as applied current, initial pH and initial dye concentration was studied in an attempt to reach higher decolorization efficiency. The degradation and mineralization of BY2 using CNT-PTFE electrode were followed by total organic carbon (TOC) and GC–MS analysis. The results of TOC measurements indicated that peroxi-coagulation with carbon-PTFE allowed 81% mineralization after 6h of electrolysis; whereas peroxi-coagulation with CNT-PTFE yields 92% mineralization under the same conditions. GC–MS analysis verified the identity of intermediates and a reaction pathway based on them was proposed. [Copyright &y& Elsevier]

In recent years, Metal-organic frameworks (MOFs) have received significant attention to adsorb arsenic from aqueous media. In this study, magnetic Fe 3 O 4 @SiO 2 -MIL-53(Fe) was prepared and characterized by XRD, SEM, EDX, FTIR, VSM, and BET techniques. The synthesized Fe 3 O 4 @SiO 2 -MIL-53(Fe) was successfully applied to remove arsenate with a maximum adsorption capacity of 70.1 mg/g. The adsorbent capability was tested in different pH, co-existing ions, and trace arsenate concentrations, and their particles were easily separated from the solution by an external magnetic field. Adsorption and VSM tests showed that the adsorbent capacity and magnetic properties were preserved after four cycles. The adsorption process obeyed the pseudo-second-order model and the experimental data well fitted with Langmuir monolayer isotherm. Immobilization of Fe 3 O 4 @SiO 2 nanoparticles into the MIL-53(Fe) structure was reduced iron ions leaching to the solution. For the first time, the Fe 3 O 4 @SiO 2 -MIL-53(Fe) composite was successfully used to remove arsenic from contaminated surfaces and groundwater. [Display omitted] • Successfully synthesis of Fe 3 O 4 @SiO 2 -Mil-53(Fe) composite. • High performance of composite in As(V) removal. • Application of composite in arsenic removal from contaminated surfaces and groundwater for the first time. • Reduction in iron leaching to the solution. • The efficiency of composite to uptake trace As(V) contamination. [ABSTRACT FROM AUTHOR]

In this study, the heterogeneous electro-Fenton method was used to remove Paclitaxel as an antineoplastic medicine. The cathode based on three-dimensional graphene (3DG) was applied as a gas diffusion electrode. The potential of five eco-friendly and recyclable iron minerals derived from nature (Magnetite, Siderite, Hematite, Limonite, and Pyrite) was investigated. Among the applied iron minerals, Pyrite showed the best, and Magnetite and Siderite showed good catalytic activity at pH 3.0. The current intensity of 300 mA, pH i 7.0, Paclitaxel concentration of 3 mg L−1, amount of Pyrite 4.5 g L−1, and time of 120 min was the optimum condition of the process with the removal efficiency of 99.13% in the presence of Pyrite. Repeating the experiments eight times revealed the reusability of the prepared 3DG as a cathode. Also, using radical scavengers indicated the principal role of the hydroxyl radicals (OH) in the treatment process. Analysis of total organic carbon reached 77.64% mineralization of 3 mg L−1 Paclitaxel at 360 min. Finally, ten by-products of small molecules were identified by gas chromatography-mass spectrometry device. [Display omitted] • Gas diffusion electrode was applied for in situ electro-generation and activation of H 2 O 2. • Green catalysts of natural iron minerals were applied. • Pyrite demonstrated a wide pH application range. • Modeling of the operational condition was done by artificial neural network. • GC-MS was applied to determine by-products of mineralization. [ABSTRACT FROM AUTHOR]

Some of the important goals in the development of the electro-Fenton (EF) process are to increase the performance of the electrodes while reducing their size as an alternative for expensive electrodes, expanding the active pH range, and also generating reactive oxygen species (ROSs) directly without using other homo/heterogeneous catalysts. This work modified graphite felt (GF) using a rapid and in-situ synthesis with Co/Zn doped mixed-metal ZIF. After calcination, various physicochemical analyses, including XRD, SEM, and XPS, confirmed that a carbonic material doped with mixed-oxide CoO/Co 2 O 3 is embedded on the surface of GF fibers. LSV analysis showed that the modification significantly improved the electrode activity for O 2 reduction. The modified CoZnCal-GF electrode showed good performance and higher kinetics in the EF process. It removed 87% of rifampin (RIF) in a short period of 30 min without any homo/heterogeneous catalysts. The selected conditions for this process were 1.0 V, 40 mg/L, and 5.6 for applied voltage, initial RIF concentration, and pH, respectively. The non-radical species 1O 2 showed the most important role in removing RIF. LC-MS analysis was performed, and while confirming the complete removal of RIF, it was used to investigate the degradation pathway and identify the produced intermediates. [Display omitted] [ABSTRACT FROM AUTHOR]

In the present study, heterogeneous electro-Fenton (EF) process was applied to remove the sulfasalazine (SU) pharmaceutical from aqueous solutions. In the first part, 3D graphene loaded with Fe@Fe 2 O 3 core-shell nanowires (Fe@Fe 2 O 3 /3D-GO) was used as a cathode electrode in the EF process. Graphene oxide (GO) was synthesized for the synthesis of 3D graphene nanocomposites using the improved Hummers' method and subsequently 3D graphene synthesized by the hydrothermal method using glycine. Finally, Fe@Fe 2 O 3 /3D-GO composite was synthesized and its properties were assessed by Scanning electron microscopy, Atomic force microscopy, Brunauer–Emmett–Teller, Fourier-transform infrared spectroscopy and X-ray diffraction methods. Then, the cathode electrode was prepared using the resulting composite and its performance was evaluated using Cyclic Voltammetry analysis. In the final part of this work, the Fe@Fe 2 O 3 /3D-GO electrode was used as the cathode electrode in the heterogeneous EF process to remove SU from aqueous solutions. The effect of operating parameters such as applied current (mA), initial pH of solution, initial pharmaceutical concentration (mg L−1) and process time (min) on pharmaceutical removal efficiency under heterogeneous EF process was investigated by response surface methodology. The results showed that the optimum values for applied current, pH, initial pharmaceutical concentration and electrolysis time were respectively 300 mA, 7, 30 mg L−1 and 100 min, resulting 99.60% of SU removal. Finally, the intermediates of SU degradation were determined by Gas chromatography–mass spectrometry analysis and the amount of mineralization was determined by total organic carbon analysis. About 5.2% drop in the SU removal efficiency was observed within 8 operational runs. [Display omitted] • 3D graphene loaded with Fe@Fe 2 O 3 core-shell nanowires was applied as cathode. • Electro-Fenton method was applied for Sulfasalazine degradation. • Response surface methodology was used to predict the removal efficiency. • Applied cathode demonstrated 99.60% of Sulfasalazine removal efficiency. • Sulfasalazine removal pH was at neutral range. [ABSTRACT FROM AUTHOR]