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Linoleic acid (LA) was investigated as an electron transfer catalyst in biomimetic lignin degradation with an electrolytic mediator system (EMS). Initial attempts of electro-oxidations of synthetic lignin, guaiacyl (G)-type dehydrogenation polymer (G-DHP), with LA alone at 0.8 V and 1.8 V, resulted in limited G-DHP conversion, suggesting that LA-mediated EMS is not effective when LA was used alone. Next, electro-oxidations of G-DHP with LA with O2-sparging as well as in the presence of co-catalysts, such as p-coumaric acid (PCA), tris(2,2′-bipyridine) iron(II) [Fe(bpy)3], and 1-hydroxybenzotriazole (HBT) were performed. The combined use of oxygen and co-catalysts appeared to be effective to promote G-DHP conversion. In particular, G-DHP conversion proceeded effectively in the electro-oxidation with LA/HBT at 0.6 V, as demonstrated by structural analysis of the electrolysis residues using nuclear magnetic resonance. HBT was also found to be a vital mediator when used alone in the present system. Overall, the combined use of oxygen and co-catalysts was essential for the EMS oxidation with LA, as reported in laccase mediator system (LMS) oxidation with LA. [ABSTRACT FROM AUTHOR]

The modification of catalytic activity through the use of metallic promoters is a key strategy for optimizing performance, as electronic factors play a crucial role in regulating catalytic behavior. This study explores the electronic factors behind the adsorption of glycerol (Gly) on bimetallic nickel-based compounds ( Ni 3 X ) using density functional theory (DFT) calculations; incorporating Mn, Fe, Co, Cu, and Zn as promoters effectively tunes the d-band center of these systems, directly influencing their magnetic, adsorption, and catalytic properties. A good correlation between the calculated glycerol adsorption energy and the d-band filling of the studied bimetallic surfaces was identified. Interestingly, this correlation can be rationalized using the celebrated Newns–Anderson model based on the calculated d-band fillings and centers of the systems under study. Additionally, the adsorption energies and relative stability of other electro-oxidation intermediates toward dihydroxyacetone (DHA) were calculated. Notably, the Ni 3 Co and Ni 3 Cu systems exhibit an optimal balance between glycerol adsorption and DHA desorption, making them promising candidates for glycerol electro-oxidation. These theoretical insights address fundamental aspects of developing glycerol valorization processes and advancing alcohol electro-oxidation technologies in fuel cells with noble-metal-free catalysts. [ABSTRACT FROM AUTHOR]

Isochroman and azole moieties are both present in a wide variety of biologically active molecules. Their efficient combination under mild reaction conditions is beneficial for obtaining small-molecule drug candidates. In this paper, we describe electrochemical α-C(sp3)–H/N–H cross-coupling reactions between isochromans and azoles, yielding products in moderate to excellent yields. This protocol does not require any catalysts or exogenous oxidants and can be performed at room temperature under air. Control experiments and cyclic voltammetry showed that the reaction may proceed through both radical coupling and nucleophilic addition processes. [ABSTRACT FROM AUTHOR]

In this investigation, metronidazole was degraded in an aqueous solution through electro-oxidation. A DiaClean® cell was used to accommodate a stainless-steel electrode as a cathode and a boron-doped diamond (BDD) electrode as anode. This setup provides several electrochemical advantages, including low currents, a high operational potential, and, frequently, low adsorption compared to conventional carbon materials. The physicochemical parameters were estimated after 180 min of treatment, applying different current densities. The concentration of metronidazole was monitored by HPLC to assess degradation, resulting in 30.67% for 30 mA cm−2, 79.4% for 50 mA cm−2, and 100% for 100 mA cm−2. The TOC mineralization percentages were 12.71% for 30 mA cm−2, 14.8% for 50 mA cm−2, and 29.9% for 100 mA cm−2. Also, biodegradability indices of 0.70 for 30 mA cm−2, 0.81 for 50 mA cm−2, and 0.93 for 100 mA cm−2 were obtained. The byproducts found were formic acid and acetic acid. A pseudo-first order kinetic model was thus obtained due to the quasi-stable concentration achieved through hydroxyl radicals, given that they do not accumulate in the medium, due to their high rate of destruction and short lifespan. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Linoleic acid (LA) was investigated as an electron transfer catalyst in biomimetic lignin degradation with an electrolytic mediator system (EMS). Initial attempts of electro-oxidations of synthetic lignin, guaiacyl (G)-type dehydrogenation polymer (G-DHP), with LA alone at 0.8 V and 1.8 V, resulted in limited G-DHP conversion, suggesting that LA-mediated EMS is not effective when LA was used alone. Next, electro-oxidations of G-DHP with LA with O2-sparging as well as in the presence of co-catalysts, such as p-coumaric acid (PCA), tris(2,2′-bipyridine) iron(II) [Fe(bpy)3], and 1-hydroxybenzotriazole (HBT) were performed. The combined use of oxygen and co-catalysts appeared to be effective to promote G-DHP conversion. In particular, G-DHP conversion proceeded effectively in the electro-oxidation with LA/HBT at 0.6 V, as demonstrated by structural analysis of the electrolysis residues using nuclear magnetic resonance. HBT was also found to be a vital mediator when used alone in the present system. Overall, the combined use of oxygen and co-catalysts was essential for the EMS oxidation with LA, as reported in laccase mediator system (LMS) oxidation with LA.

The waste acid generated in the production of expanded graphite by “chromium method” has the characteristics of high acid concentration and high chromium content. The Cr(Ⅲ) can be oxidized to Cr(Ⅵ) by electro-oxidation in membrane system to realize the regeneration of waste acid containing chromium. Since it was difficult to achieve real-time detection of Cr(Ⅵ) content in this highly acidic system, a study based on artificial neural network was conducted to accurately predict the electro-oxidation regeneration effect of chromium-containing waste acid. Based on the regeneration of chromium-containing waste acid experiments, the key characteristic parameters of hexavalent chromium regeneration including time, sulfuric acid concentration, and electrolyte volume were determined by correlation analysis. Then, through hyperparameter optimization, the relatively optimal topology structure of the artificial neural network was obtained as follows: Neurons=35, Batch size=30, Layers=4. The coefficient of determination(R2) between predicted value and experimental value was greater than 0.97, and the root-mean-square error(RMSE) was less than 0.04. Finally, the average relative error between predicted value and experimental value was 0.14%, which indicated that the model had good generalization ability. The artificial neural network model overcame the difficulty of predicting electrochemical processes due to multi-parameter, nonlinearity and time variability, and could realize the prediction of Cr(Ⅵ) regeneration under complex mapping conditions, which was of great significance for the optimization and control of electrochemical processes.

Abstract Algogenic organic matter (AOM) generated from cyanobacteria-impacted reservoirs poses a significant risk to drinking water. This study aimed to investigate the molecular degradation signature of Microcystis aeruginosa (MA)-derived AOM by electrochemical oxidation and the corresponding disinfection by-product formation potential (DBPFP). Boron-doped diamond (BDD)-based electro-oxidation (EO) and electro-Fenton (EF) were implemented at pH 3 and 10 mA cm−2 within 1 h. The fluorophore of extracellular organic matter (EOM), the mixture of EOM and intracellular organic matter (IOM), were characterized, and their corresponding molecular weight (MW) were fractionated. The results showed that dissolved organic carbon (DOC) degradation efficiency for BDD-EF treatment is superior and maintains DOC attenuation up to 84% for the EOM suspensions alone, while a low degradation efficiency occurs for IOM-EOM mixture. In contrast, BDD-EO exhibits a maximum DOC degradation around 66% for EOM suspensions alone, but DOC reduction is as low as 20% for IOM-EOM mixture. The H2O2 generated by BDD-EO preferentially degrades humic acid-like substances in EOM suspensions, whereas BDD-EF effectively degrades multiple fluorescent AOM by •OH. For IOM-EOM mixture, BDD-EO efficiently decomposes humics, but BDD-EF preferentially minimizes soluble microbial product-like and aromatic protein-like substances. Meanwhile, BDD-EF favors degrading biopolymers, humics, and low-MW substances, while BDD-EO merely degrades partial biopolymers and humic substances. After either EF or EO, specific DBPFP decreases as EOM presents alone where the toxicity of corresponding DBPs is mitigated effectively, instead the increased specific DBPFP appears for IOM-EOM mixture where the toxic potency ([DBP]/LC50) of corresponding DBPs increases. In summary, EO and EF are powerful in attenuating MA-derived DBP precursors of EOM in the absence of IOM, depending on the molecular signature.

Copyright of Iraqi Journal of Chemical & Petroleum Engineering is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Algogenic organic matter (AOM) generated from cyanobacteria-impacted reservoirs poses a significant risk to drinking water. This study aimed to investigate the molecular degradation signature of Microcystis aeruginosa (MA)-derived AOM by electrochemical oxidation and the corresponding disinfection by-product formation potential (DBPFP). Boron-doped diamond (BDD)-based electro-oxidation (EO) and electro-Fenton (EF) were implemented at pH 3 and 10 mA cm−2 within 1 h. The fluorophore of extracellular organic matter (EOM), the mixture of EOM and intracellular organic matter (IOM), were characterized, and their corresponding molecular weight (MW) were fractionated. The results showed that dissolved organic carbon (DOC) degradation efficiency for BDD-EF treatment is superior and maintains DOC attenuation up to 84% for the EOM suspensions alone, while a low degradation efficiency occurs for IOM-EOM mixture. In contrast, BDD-EO exhibits a maximum DOC degradation around 66% for EOM suspensions alone, but DOC reduction is as low as 20% for IOM-EOM mixture. The H2O2 generated by BDD-EO preferentially degrades humic acid-like substances in EOM suspensions, whereas BDD-EF effectively degrades multiple fluorescent AOM by •OH. For IOM-EOM mixture, BDD-EO efficiently decomposes humics, but BDD-EF preferentially minimizes soluble microbial product-like and aromatic protein-like substances. Meanwhile, BDD-EF favors degrading biopolymers, humics, and low-MW substances, while BDD-EO merely degrades partial biopolymers and humic substances. After either EF or EO, specific DBPFP decreases as EOM presents alone where the toxicity of corresponding DBPs is mitigated effectively, instead the increased specific DBPFP appears for IOM-EOM mixture where the toxic potency ([DBP]/LC50) of corresponding DBPs increases. In summary, EO and EF are powerful in attenuating MA-derived DBP precursors of EOM in the absence of IOM, depending on the molecular signature. [ABSTRACT FROM AUTHOR]

Fluoxetine (FLX) is a selective serotonin reuptake inhibitor (SSRI) medication commonly used to treat mental health disorders, but it can be harmful to the environment if not properly disposed of due to incomplete metabolism. In this study, electrochemical anodic oxidation with mixed metal oxide anodes was studied as a method to remove FLX from water and wastewater. Iridium dioxide-coated titanium (Ti/IrO2) and ruthenium dioxide-coated Ti (Ti/RuO2) electrodes were found to be more effective than platinum-coated Ti (Ti/Pt) electrodes, with removal efficiencies of 91.5% and 93.9%, respectively. Optimal conditions for FLX removal were determined to be an applied current of 150 mA, initial pH of 5, and oxidation time of 120 min. The rate of FLX degradation (kFLX) for the Ti/Pt, Ti/IrO2, and Ti/RuO2 electrodes were determined to be 0.0081 min−1 (R2:0,8161), 0.0163 min−1 (R2:0,9823), and 0.0168 (R2:0,9901) min−1 for 25 mg/L initial FLX concentration, respectively. The kFLX values varied based on the initial FLX concentration and decreased as the initial FLX concentration increased. The specific energy consumption (SEC) after 120 min of operation was 51.0 kWh/m3 for the Ti/Pt electrode, 39.6 kWh/m3 for the Ti/IrO2 electrode, and 48.6 kWh/m3 for the Ti/RuO2 electrode under optimised conditions. Overall, electrochemical anodic oxidation is an effective method for removing FLX from water and wastewater, with Ti/IrO2 and Ti/RuO2 electrodes providing superior performance compared to Ti/Pt electrodes. [ABSTRACT FROM AUTHOR]

In this experiment, we prepared, characterized, and utilized PtBi supported on carbon cloth as a self- supporting electrode for electro-oxidation applications. The aim was to promote the integration of science and education and foster the development of innovative talents. Through this experiment, students can gain a better understanding of electrochemical devices and energy conversion in Physical Chemistry, as well as catalyst performance evaluation criteria. It also aims to stimulate students’ interest in scientific research and equip them with essential laboratory skills such as the preparation, characterization, and electrochemical testing of nanomaterials. This experiment aims to enhance students’ scientific literacy and improve their ability to analyze performance data, comprehend electro-oxidation reaction processes, and understand electrode processes using electrochemical and kinetic concepts. [ABSTRACT FROM AUTHOR]

The release of anaerobically digested dairy wastewater (ANDDW) without a treatment can lead to severe environmental pollution, prompting the exploration of effective and sustainable treatment methods. Amidst various wastewater treatment approaches, the electro-oxidation (EO) process is considered as a promising, clean, and adaptable solution. In this study, the major operational parameters viz. current density, electrolyte concentration, treatment time, and mixing speed of an EO comprising Ti/PbO2 anode and stainless-steel cathode, were optimized using response surface methodology (RSM) for efficient removal of chemical oxygen demand (COD), ammonia nitrogen (NH3-N), total phosphorus (TP), orthophosphate (OP), total nitrogen (TN), and total Kjeldahl nitrogen (TKN) from ANDDW. Optimal conditions were identified as a current density of 90 mA cm−2, 0.08% electrolyte concentration, 180 min treatment time, and 400 rpm mixing speed. Under the optimum conditions, the COD, NH3-N, TP, OP, TN, and TKN removal efficiencies were 78.36, 63.93, 87.41, 92.39, 67.01, and 81.42%, respectively. Furthermore, the reaction rate followed the first-order kinetic model for the pollutants removal with correlation coefficients (R2) close to 1. The findings highlight the potential of using the EO process to treat high pollutant-laden ANDDW and encourage further studies to confirm the corresponding outcomes on a pilot scale. [ABSTRACT FROM AUTHOR]

Biomass feedstock ethylene glycol (EG) can be anodically oxidized to the high‐value glycolic acid (GA), which is widely considered as one critical raw material of biodegradable plastics. Developing low‐cost electrocatalyst to economically produce GA with high selectivity still meeting challenges. Herein, a non‐precious Co‐Ni bimetal catalysts are developed for controllable electrooxidizing EG to GA (EGOR). Through regulating the generation of key intermediate (CH2OH‐CO*) on the low‐cost catalyst surface, a successive electrooxidation from EG to GA has been achieved with high selective (96.3%) and conversion rate (>85%) at current density of 150 mA cm−2, which is on par with the reported precious metal catalysts. Through coupling with hydrogen evolution reaction (EGOR‐HER), 2.759 mmol H2 and 7.48 mmol of GA are generated at 80 mA cm−2, which also can save 27% energy comparing with a water splitting system. The synergistic effect between Co and Ni in the bimetallic catalyst has been exploited: high‐valent CoOOH sites catalyzed the generation of CH2OH‐CO* and reduce the energy barrier during GA formation; Whereas, Ni sites can effectively facilitate the formation of CoOOH and improve the adsorption of EG. [ABSTRACT FROM AUTHOR]

The present research aimed to explore the durability of MMO electrodes through electro-oxidation (EO) in purifying secondary treated actual sewage wastewater using batch and pilot-scale setups. The main aim is to inactivate bacteria in sewage treatment plants before they are released into the environment, thus contaminating water and soil. Process parameters such as current density (j), NaCl dose (n), and treatment time (t) were optimized using response surface methodology in a lab-scale EO reactor under batch conditions. The results showed that optimization of current density at 5.90 mA/cm2 and NaCl concentration at 1.31 g/L led to 93.90% of bacterial inactivation (Q1) within 8 min of treatment and 0.48 kWh/m3 energy consumption (Q2). Biological analysis was conducted to validate bacterial cell destruction and count coliform bacteria in the EO-treated sewage wastewater. XRD, cyclic voltammetry studies, and FE-SEM/EDS analysis were done to confirm the MMO anode's durability and stability after 100 recycles. The study prioritized bacterial inactivation along with organic matter degradation. Besides that, a small pilot-scale study on the actual sewage wastewater with a volume of 10–50 L was done in batch mode under previously optimized conditions to analyze the efficacy of the MMO anodes in terms of bacterial inactivation. [ABSTRACT FROM AUTHOR]

Ammonia nitrogen wastewater is one of the most difficult water treatment problems in the world. In the process of uranium mining, beneficiation and smelting, radioactive solid waste will be produced which cann’t be effectively treated, and will be stored in uranium tailings pond for a long time. Due to the role of rainwater, tailings pond will produce a large amount of wastewater, leach harmful substances into the water to form percolation drainage. Uranium tailings percolation drainage has the characteristics of high salt, high ammonia nitrogen, poor biodegradability and high chloride ion content, and the components in different regions of tailings pond are greatly different. Existing ammonia nitrogen treatment methods can’t effectively treat complex wastewater. Electro-oxidation method is a clean and efficient method to remove ammonia nitrogen in wastewater. By using electric energy and catalytic oxidation of anode and cathode plates, as well as indirect oxidation, chlorine ions in water are converted into highly oxidizing hypochlorite ions, and ammonia nitrogen is converted into harmless nitrogen by strong oxidation, so as to achieve harmless treatment of wastewater and no secondary waste is generated. In this paper, the principle and chemical reaction process of ammonia nitrogen removal by electro-oxidation were analyzed, and the factors affecting the removal rate of ammonia nitrogen were clarified, including chloride ion concentration, plate material, current density, pH, etc., and the influence of each factor on the electro-oxidation process was determined by single factor test. Through orthogonal analysis, the influence degree of each factor on the ammonia nitrogen removal rate was explored, and the influence degree of each factor was ranked from high to low, in order of chloride ion concentration>plate material>current density. pH is a secondary factor, which provides alkaline environment for electrochemical reaction and has little effect on ammonia nitrogen removal. The removal rate of ammonia nitrogen is significantly improved under different conditions, among which chloride ion is the most obvious, and the removal rate of ammonia nitrogen increases from 43.4% at 369 mg/L chloride ion concentration to 96% at 1000 mg/L. Finally, the Ti/RuO2-IrO2-SnO2 electrode set is recommended. The optimal conditions are chloride ion concentration of 1 000 mg/L, current density of 20 mA/cm2, electrolytic time of 3 h, pH=9-11, under which the removal rate of ammonia nitrogen is 100%. The effluent of ammonia nitrogen meets the requirements of ‘Regulations on Radiation Protection and Radiation Environment Protection for Uranium Mining and Metallurgy’ and ‘Comprehensive Sewage Discharge Standard’.

Efficcient elecctro-oxidation of 5-hydroxymethylfurfural (HMF) to produce 2,5-furandicarboxylic acid (FDCA) was achieved in a low-concentrated alkaline electrolyte over a single-atom-ruthenium supported on Co 3 O 4 (Ru 1 -Co 3 O 4). Single-atom-Ru enhances hydroxyl (OH–) adsorption, thereby improving the oxidation of HMF. The design for the Ru 1 -Co 3 O 4 catalyst enables efficient HMF-to-FDCA electrocatalysis without using strong alkaline electrolytes, which may greatly improve the profitability of HMF-to-FDCA electroccatalysis. [Display omitted] Electrocatalytic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), a sustainable strategy to produce bio-based plastic monomer, is always conducted in a high-concentration alkaline solution (1.0 mol L−1 KOH) for high activity. However, such high concentration of alkali poses challenges including HMF degradation and high operation costs associated with product separation. Herein, we report a single-atom-ruthenium supported on Co 3 O 4 (Ru 1 -Co 3 O 4) as a catalyst that works efficiently in a low-concentration alkaline electrolyte (0.1 mol L−1 KOH), exhibiting a low potential of 1.191 V versus a reversible hydrogen electrode to achieve 10 mA cm−2 in 0.1 mol L−1 KOH, which outperforms previous catalysts. Electrochemical studies demonstrate that single-atom-Ru significantly enhances hydroxyl (OH−) adsorption with insufficient OH− supply, thus improving HMF oxidation. To showcase the potential of Ru 1 -Co 3 O 4 catalyst, we demonstrate its high efficiency in a flow reactor under industrially relevant conditions. Eventually, techno-economic analysis shows that substitution of the conventional 1.0 mol L−1 KOH with 0.1 mol L−1 KOH electrolyte may significantly reduce the minimum selling price of FDCA by 21.0%. This work demonstrates an efficient catalyst design for electrooxidation of biomass working without using strong alkaline electrolyte that may contribute to more economic biomass electro-valorization. [ABSTRACT FROM AUTHOR]

Direct hydrazine fuel cells (DHFC) insist on the evolved and persistent electrocatalysts for anodic hydrazine oxidation reaction (HzOR). Herein, PdO promoted CuO heterostructures supported on γ‐Al2O3 are depicted as efficient electrocatalysts for HzOR. γ‐Al2O3 is prepared by precipitation method while metal precursors are incorporated by co‐impregnation technique. Physiochemically characterized PdO‐CuO/Al2O3 mesoporous composites displayed large electrochemical active surface area (ECSA) i. e., 0.18 cm2, high current density (j) i. e., 35.7 mA cm−2, larger diffusion coefficient (D°) i. e., 29.3×10−4 (cm2s−1), large apparent rate constant (kapp) i. e., 13.2 cm−1 with low charge transfer resistance (Rct) i. e., 3.6 kΩ shown by the best catalyst i. e., 1 % PdO‐CuO/Al2O3. Cyclic voltammetry indicated that the fabricated working electrodes offer high efficiency towards HzOR in alkaline medium in such a way that 1 % PdO‐CuO/Al2O3 produced 600 times higher oxidation current than CuO/Al2O3 composite. Owing to stability and reproducibility, PdO modified CuO/Al2O3 would achieve a huge catalytic significance in multiple electrochemical oxidation reactions with economic and ecological benefits. [ABSTRACT FROM AUTHOR]

Electro‐oxidation (EO) technology demonstrates significant potential in wastewater treatment. However, the high energy consumption has become a pivotal constraint hindering its large‐scale implementation. Herein, we design an EO and 4‐electron oxygen reduction reaction coupled system (EO‐4eORR) to replace the traditional EO and hydrogen evolution reaction (HER) coupled system (EO‐HER). The theoretical cathodic potential of the electrolytic reactor is tuned from 0 V (vs. RHE) in HER to 1.23 V (vs. RHE) in 4eORR, which greatly decreases the required operation voltage of the reactor. Moreover, we demonstrate that convection can improve the mass transfer of oxygen and organic pollutants in the reaction system, leading to low cathodic polarization and high pollutant removal rate. Compared with traditional EO‐HER system, the energy consumption of the EO‐4eORR system under air aeration for 95 % total organic carbon (TOC) removal is greatly decreased to 2.61 kWh/kgTOC (only consider the electrolyzer energy consumption), which is superior to previously reported EO‐based water treatment systems. The reported results in this study offer a new technical mode for development of highly efficient and sustainable EO‐based treatment systems to remove organic pollutants in waste water. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Metoprolol is a cardioselective beta-blocker drug often used to treat hypertension, but it is considered as a hazardous organic persistent contaminant in wastewater. In this study, a 2.5 L solution of metoprolol (50 mg/L) underwent electro-oxidation in a flow-by reactor using boron-doped diamond electrodes in the batch recirculation mode. The study used multi-objective optimization and multi-criterion decision-making to determine the optimal operating parameters. The response surface methodology and a central composite rotatable design were used with three factors (pH0: 5–8, I: 2.5–4 A, and Q: 0.8–1.7 L/min) to model the chemical oxygen demand's (COD's) removal efficiency and the total organic carbon's (TOC's) removal efficiency. The experimental responses were modeled by reduced third- and second-order polynomials with determination coefficients (R2) of 0.9816 and 0.9430. The optimal operating parameters were found to be pH0 5, an I value of 3.84 A, and a Q value of 0.8 L/min with an electrolysis time of 7.5 h, resulting in a maximum COD removal efficiency of 60.8% and a TOC removal efficiency of 90.1%. The specific energy consumption was calculated as 9.61 kWh/mg of TOC, with a total operating cost of 0.77 USD/L. In conclusion, this study showed that the electrochemical process is efficient and reliable for treating wastewater containing metoprolol. [ABSTRACT FROM AUTHOR]

We introduce a novel dual redox mediator synthesized by covalently linking ferrocene dicarboxylic acid (FcDA) and thionine (TH) onto a pre-treated glassy carbon electrode. This unique structure significantly enhances the electro-oxidation of dopamine (DA) and the reduction of hydrogen peroxide (H2O2), offering a sensitive detection method for both analytes. The electrode exhibits exceptional sensitivity, selectivity, and stability, demonstrating potential for practical applications in biosensing. It facilitates rapid electron transfer between the analyte and the electrode surface, detecting H2O2 concentrations ranging from 1.5 to 60 µM with a limit of detection (LoD) of 0.49 µM and DA concentrations from 0.3 to 230 µM with an LoD of 0.07 µM. The electrode's performance was validated through real-sample analyses, yielding satisfactory results. [ABSTRACT FROM AUTHOR]

A multifactor interaction study was performed using the combined response surface methodology and an artificial neural network on the operational parameters and their influence on residual chlorine production. The operating variables, sodium chloride concentration, electrical potential, electrolysis time, and electrode gap, were evaluated over the response, residual chlorine and energy consumption. The results indicated that the optimum value for residual chlorine was 2450 mg/L achieved at an electrical potential of 8.8 V for 25 min in the presence of 25 g/L of sodium chloride and an electrode distance of 1 cm, and the optimum corresponding energy consumption was measured at 21.76 kWh/L. The study reveals that electric potential, sodium chloride concentration, and electrolysis time positively influence residual chlorine production. ANN models showed superior prediction ability compared with RSM models. This suggests electrolysis can be used for active chlorine production from saline solutions, potentially for industrial applications and water disinfection. Highlights: The electrode gap was shown to have little effect on the formation of residual chlorine.The electrolysis time and electric potential have a direct impact on energy consumption.Artificial neural network models demonstrated superior capability for process prediction.A maximum of 21.756 kWh/L of energy can be utilized for producing residual chlorine. [ABSTRACT FROM AUTHOR]

The removal of congo red (CR) is a critical issue in contemporary textile industry wastewater treatment. The current study introduces a combined electrochemical process of electrocoagulation (EC) and electro-oxidation (EO) to address the elimination of this dye. Moreover, it discusses the formation of a triple composite of Co, Mn, and Ni oxides by depositing fixed salt ratios (1:1:1) of these oxides in an electrolysis cell at a constant current density of 25 mA/cm2. The deposition ended within 3 hours at room temperature. X-ray diffractometer (XRD), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), and energy dispersive X-ray (EDX) characterized the structural and surface morphology of the multi-oxide sediment. Marvelously, the deposition has simultaneously occurred on both anodic and cathodic graphite electrodes. These electrodes besides aluminum (Al) are employed as anodes in the EC-EO system, and the results were optimized by response surface methodology (RSM). The optimum operating conditions were a current density of 6 mA/cm2, pH = 7, and NaCl of 0.26 g/L. The results showed that the combined system eliminated more than 99.91% of the congo red dye with a removal of chemical oxygen demand (COD) of around 97% with 1.64 kWh/kg of dye of the consumed energy. At low current density, the current delivered for the composite anode was more than for the Al anode with the same surface area. On top of this superiority, the EC-EO scenario is a practical hybrid process to remove CR in an environmentally friendly pathway. [ABSTRACT FROM AUTHOR]

Animal farming wastewater is one of the most important sources of ammonia nitrogen (NH4+-N) emissions. Electro-oxidation can be a viable solution for removing NH4+-N in wastewater. Compared with other treatment methods, electro-oxidation has the advantages of i) high removal efficiency, ii) smaller size of treatment facilities, and iii) complete removal of contaminant. In this study, a previously prepared DSA (W, Ti-doped IrO2) was used for electro-oxidation of synthetic mariculture and livestock wastewater. The DSA was tested for chlorine evolution reaction (CER) activity, and the reaction kinetics was investigated. CER current efficiency reaches 60–80% in mariculture wastewater and less than 20% in livestock wastewater. In the absence of NH4+-N, the generation of active chlorine follows zero-order kinetics and its consumption follows first-order kinetics, with cathodic reduction being its main consumption pathway, rather than escape or conversion to ClO3−. Cyclic voltammetry experiments show that NH4+-N in the form of NH3 can be oxidized directly on the anode surface. In addition, the generated active chlorine combines with NH4+-N at a fast rate near the anode, rather than in the bulk solution. In electrolysis experiments, the NH4+-N removal rate in synthetic mariculture wastewater (30–40 mg/L NH4+-N) and livestock wastewater (~ 450 mg/L NH4+-N) is 112.9 g NH4+-N/(m2·d) and 186.5 g NH4+-N/(m2·d), respectively, which is much more efficient than biological treatment. The specific energy consumption (SEC) in synthetic mariculture wastewater is 31.5 kWh/kg NH4+-N, comparable to other modified electro-catalysts reported in the literature. However, in synthetic livestock wastewater, the SEC is as high as 260 kWh/kg NH4+-N, mainly due to the suppression of active chlorine generation by HCO3− and the generation of NO3− as a by-product. Therefore, we conclude that electro-oxidation is suitable for mariculture wastewater treatment, but is not recommended for livestock wastewater. Electrolysis prior to urea hydrolysis may enhance the treatment efficiency in livestock wastewater. [ABSTRACT FROM AUTHOR]