Electrochemical Wastewater Treatment Research Articles

Developments and Advances in Electrode Materials for Electrochemical Treatment of Industrial Wastewater

Developments and Advances in Electrode Materials for Electrochemical Treatment of Industrial Wastewater

Electrochemical Methods for Nutrient Removal in Wastewater: A Review of Advanced Electrode Materials, Processes, and Applications

In response to the increasing global water demand and the pressing environmental challenges posed by climate change, the development of advanced wastewater treatment processes has become essential. This study introduces novel electrochemical technologies and examines the scalability of industrial-scale electrooxidation (EO) methods for wastewater treatment, focusing on simplifying processes and reducing operational costs. Focusing on the effective removal of key nutrients, specifically nitrogen and phosphorus, from wastewater, this review highlights recent advancements in electrode materials and innovative designs, such as high-performance metal oxides and carbon-based electrodes, that enhance efficiency and sustainability. Additionally, a comprehensive discussion covers a range of electrochemical methods, including electrocoagulation and electrooxidation, each evaluated for their effectiveness in nutrient removal. Unlike previous studies, this review not only examines nutrient removal efficiency, but also assesses the industrial applicability of these technologies through case studies, demonstrating their potential in municipal and industrial wastewater contexts. By advancing durable and cost-effective electrode materials, this study emphasizes the potential of electrochemical wastewater treatment technologies to address global water quality issues and promote environmental sustainability. Future research directions are identified with a focus on overcoming current limitations, such as high operational costs and electrode degradation, and positioning electrochemical treatment as a promising solution for sustainable water resource management on a larger scale.

Attracting magnetic BDD particles onto Ti/RuO2-IrO2 by using a magnet: A novel 2.5-dimensional electrode for electrochemical oxidation wastewater treatment

Boron-doped diamond (BDD) is a well-known anode material with a high pollutant degradation ability for electrochemical oxidation wastewater treatment. Nevertheless, the cost of production and mechanical strength of BDD membranes remain unsatisfactory. Magnetic BDD particles derived from industrial waste may represent a promising alternative to BDD membranes, although the challenge remains in assembling these particles into a usable electrode. In this study, magnetic BDD particles were attracted to a Ti/RuO2-IrO2 electrode using a magnet, thus constituting a novel 2.5-dimensional (2.5D) electrode. To ascertain the structure-activity relationship of the novel electrode, essential characterizations, multi-physics simulations, pollutant degradation and electrosynthesis experiments were conducted. The results indicate that an appropriate quantity of BDD particles (0.1 g/cm2) can enhance the number of active sites by approximately 20%. A strong synergistic effect was observed between the Ti/RuO2-IrO2 and BDD particles in the degradation of various pollutants, including azo dye, p-benzoquinone, succinic acid and four kinds of real wastewaters, as well as glycerol conversion. The joint active sites on the interface between Ti/RuO2-IrO2 and BDD particles, as well as the inner active sites on BDD particles, have been identified as crucial in the mineralization of pollutants and the generation of value-added products. The optimal amount of BDD particles (0.1 g/cm2) is sufficient to preserve the joint active sites and to maintain an adequate polarization on the BDD particles. Nevertheless, the hybrid feature of the 2.5D electrode is diminished when a greater quantity of BDD particles (0.3 g/cm2) is loaded.

Improved kitchen wastewater treatment using PbO2-coated graphite electrode

This study investigates the electrochemical treatment of kitchen wastewater (KW) using a PbO₂-coated graphite (G-PbO₂) electrode prepared via ultrasound-assisted electrochemical deposition. The G-PbO2 electrode was characterised through various techniques, including X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM), confirming the successful deposition of PbO₂ and enhanced catalytic activity. Under optimal conditions (current density 0.75 Adm−2, electrolyte concentration 1.5 gL-1, electrode distance 2 cm, and pH 3), the G-PbO₂ electrode achieved a 94 % COD reduction with an energy consumption of 0.002 kWh gCOD−1. These results highlight the superior performance of the electrode in COD removal, accompanied by low energy consumption.

Inhibition of inorganic chlorinated byproducts formation during electrooxidation treatment of saline phenolic wastewater via synergistic cathodic generation of H2O2

The electrochemical treatment of saline wastewater is prone to the formation of inorganic chlorinated byproducts, being a significant challenge for this technology. In this study, we introduce an electrooxidation system utilizing a self-supporting nitrogen-doped carbon-based cathode embedded in carbon cloth (N@C-CC), designed to generate H₂O₂. This system aims to rapidly neutralize free chlorine produced at the anode, a precursor to inorganic chlorinated byproducts, thereby reducing their formation. Our results demonstrate that using the N@C-CC cathode in saline wastewater treatment yielded considerably lower concentrations of ClO₃⁻ and ClO₄⁻ (0.08 mM and 0.024 mM, respectively), which were only 20.5% and 22.7% of the levels produced using a Pt cathode without H₂O₂ generation. Moreover, the presence of cathodically generated H₂O₂ that quenches free chlorine did not significantly impact the degradation performance of phenol. Electron paramagnetic resonance tests and quenching experiments indicated that 1O₂ was primarily responsible for phenol removal. Validation with real wastewater demonstrated reductions of 68.6% and 56.3% in ClO3− and ClO4− concentrations, respectively, while effectively removing other pollutants. This study thus offers a compelling method for mitigating the formation of inorganic chlorinated byproducts during the electrooxidation of saline wastewater.

Monte Carlo Simulation, Artificial Intelligence and Machine Learning-based Modelling and Optimization of Three-dimensional Electrochemical Treatment of Xenobiotic Dye Wastewater

The present study investigates the synergistic performance of the three-dimensional electrochemical process to decolourise methyl orange (MO) dye pollutant from xenobiotic textile wastewater. The textile dye was treated using electrochemical technique with strong oxidizing potential, and additional adsorption technology was employed to effectively remove dye pollutants from wastewater. Approximately 98% of MO removal efficiency was achieved using 15 mA/cm2 of current density, 3.62 kWh/kg of energy consumption and 79.53% of current efficiency. The 50 mg/L MO pollutant was rapidly mineralized with a half-life of 4.66 min at a current density of 15 mA/cm2. Additionally, graphite intercalation compound (GIC) was electrically polarized in the three-dimensional electrochemical reactor to enhance the direct electrooxidation and.OH generation, thereby improving synergistic treatment efficiency. Decolourisation of MO-polluted wastewater was optimized by artificial intelligence (AI) and machine learning (ML) techniques such as Artificial Neural Networks (ANN), Support Vector Machine (SVM), and random forest (RF) algorithms. Statistical metrics indicated the superiority of the model followed this order: ANN > RF > SVM > Multiple regression. The optimization results of the process parameters by artificial neural network (ANN) and random forest (RF) approaches showed that a current density of 15 mA/cm2, electrolysis time of 30 min and initial MO concentration of 50 mg/L were the best operating parameters to maintain current and energy efficiencies of the electrochemical reactor. Finally, Monte Carlo simulations and sensitivity analysis showed that ANN yielded the best prediction efficiency with the lowest uncertainty and variability level, whereas the predictive outcome of random forest was slightly better.Highlights• In-depth analysis of various artificial intelligence optimization techniques.• Prediction efficiency of artificial intelligence and machine learning algorithms.• 98% dye removal and 100% regeneration of graphite intercalation compound.• Advanced statistical analysis of targeted responses and data fitting techniques.• Analysis of uncertainties and variability using Monte Carlo simulation.

Nitrosamine formation driven by electrochemical chlorination of urine-containing source waters: Effects of operational conditions

We investigated the formation of nitrosamines from urine during electrochemical chlorination (EC) using dimensionally stable anodes. Short-term electrolysis (< 1 h) of urine at 25 mA cm−2 generated seven nitrosamines (0.1–7.4 µg L−1), where N-nitrosodimethylamine, N-nitrosomethylethylamine, and N-nitrosodiethylamine were predominant with concentrations ranging from 1.2 to 7.4 µg L−1. Mechanistic studies showed that the formation kinetics of nitrosamines was influenced by urine aging and composition, with fresh urine generating the highest levels (0.9–5.8 µg L−1) compared with aged, centrifuged, or filtered urine (0.2–4.1 µg L−1). Concurrently, studies on urine pretreatment through filtration and centrifugation underscored the significance of nitrogenous metabolites (such as protein-like products and urinary amino acids) and particle-associated humic fractions in nitrosamine formation during EC of urine. This finding was confirmed through chromatographic and spectroscopic studies utilizing LCOCD, Raman spectra, and 3DEEM fluorescence spectra. Parametric studies demonstrated that the ultimate [nitrosamines] increased at a pH range of 4.5–6.2, and with increasing [bromide], [ammonium], and current density. Conversely, sulfate and carbonate ions inhibited nitrosamine formation. Moreover, the implications of EC in urine-containing source waters were evaluated. The results indicate that regardless of the urine source (individual volunteers, septic tank, swimming pool, untreated municipal wastewater), high levels of nitrosamines (0.1–17.6 µg L−1) were generated, surpassing the potable reuse guideline of 10 ng L−1. Overall, this study provides insights to elucidate the mechanisms underlying nitrosamine formation and optimize the operating conditions. Such insights facilitate suppressing the generation of nitrosamine byproducts during electrochemical treatment of urine-containing wastewater.

FeMo modified Ru@TiO2 with ultralow Ru loading towards efficient degradation of methylene blue

Dimensionally stable RuO2-based anodes have achieved excellent performance in the field of electrochemical treatment of wastewater, however, the high price of Ru hinders its industrial application. Herein, TiO2 nanotubes-supported RuO2 with ultralow Ru loading (0.34 wt%) and trace Fe and Mo doping (RuFeMo@TiO2) was prepared as anode for efficient degradation of methylene blue. It shows that Fe and Mo doping reduce the oxidation state of Ru (Run+, n < 4). In addition, the potential electroactive sites of the electrodes are effectively enhanced by Mo doping. While the Fe doping is found to improve the generation of hydroxyl radicals (·OH) and superoxide anion (O2−), which are the dominant oxidants for the degradation of methylene blue. In result, the RuFeMo@TiO2 catalyst exhibits high performance towards methylene blue degradation of 97.5 % within 2 hours. It shows that the cooperation of trace transition metals enables efficient degradation of organic dye with ultralow-loaded Ru electrocatalyst, implying a promising application in wastewater treatment.

Electrochemical treatment of azo dye wastewater by dynamic flow diaphragm system: Response surface methodology optimization and energy consumption analysis

In this experiment, the degradation process of azo dye wastewater was studied based on the diaphragm double chamber electrochemical reactor, taking the mono azo dye amaranth as an example. Through the circulation flow of appropriate volume of wastewater in the cathode and anode chamber, the simultaneous action of cathode and anode was realized, and the degradation and decolorization efficiency of azo wastewater was improved while reducing energy waste. The optimal reaction conditions optimized by response surface methodology were as follows: the voltage was 20.74 V, the plate spacing was 4.89 cm, and the cycle speed was 60.66 rad / min. The optimal decolorization rate was 99.66 %. The energy consumption analysis of the dynamic flow diaphragm system electrochemical method and the static flow diaphragm system electrochemical method for the treatment of azo dye wastewater was compared and analyzed. In addition, the possible degradation process of azo dye wastewater by dynamic flow electrochemistry was inferred by ultraviolet spectroscopy and mechanism prediction analysis. The experimental results show the great potential of the dynamic flow membrane system process in the treatment of azo dyes.

Optimized electrochemical treatment of semi-coking wastewater for enhanced degradation of biological toxicity using a Ru-Ir-Ti anode and Co-Ti cathode

The Co-Ti cathode was prepared to reduce the biological toxicity of semi-coke wastewater by electrochemical system with commercial ruthenium-iridium titanium (Ru-Ir-Ti) anode. Meanwhile, the removal rate of chemical oxygen demand (COD), volatile phenol (VP) and ammonia nitrogen (NH3-N) in wastewater were also evaluated. Hence, the influence of processing time (A), dilution multiple (B), initial pH (C), electrolyte concentration (D) and current density (D) were systematic explored. After treatment, with the optimized experiment condition of processing time (150 min), dilution multiple (300 times), initial pH (3.2), electrolyte concentration (0.15 mol/L), current density (16 mV/cm2), the B/C value of wastewater was greatly improved from 0.12 to 0.31, the removal rate of COD, NH3-N and VP was 96.82 %, 92.34 % and 97.07 %, respectively. The sequence of significance was B>D>E*E>B*D>A*D>D*D. This most effective degradation was owing to the simultaneously oxidization of both cathode and anode, turning the highly biological toxic wastewater to the biodegradable one. The direct oxidation reaction happened on anode, furthermore, the indirect oxidation reaction would be accelerated near the cathode because of active free radicals generation such as ·OH and O2•– when the cobalt’s valence changed from +2 to +3. It deserve to be mentioned in this research is that the direct and indirect oxidation simultaneously contributed to the degradation of biological toxicity, which is great beneficial for the further bio-chemical processing.

An Anti-Scaling Strategy for Electrochemical Wastewater Treatment: Leveraging Tip-Enhanced Electric Fields.

Electrode scaling poses a critical barrier to the adoption of electrochemical processes in wastewater treatment, primarily due to electrode inactivation and increased internal reactor resistance. We introduce an antiscaling strategy using tip-enhanced electric fields to redirect scale-forming compounds (e.g., Mg(OH)2 and CaCO3) from the electrode-electrolyte interface to the bulk solution. Our study utilized Cu nanowires (Cu NW) with high-curvature nanostructures as the cathode, in contrast to Cu nanoparticles (Cu NP), Cu foil (CF), and Cu mesh (CM), to evaluate the electrochemical nitrate reduction reaction (NO3RR) performance in hard water conditions. The Cu NW/CF cathode demonstrated superior NO3RR efficiency, with an apparent rate constant (Kapp) of 1.04 h-1, significantly outperforming control electrodes under identical conditions (Kapp < 0.051 h-1). Through experimental and theoretical analysis, including COMSOL simulations, we show that the high-curvature design of Cu NW induced localized electric field enhancements, propelling OH- ions away from the electrode surface into the bulk solution, thus mitigating scale formation on the cathode. Testing with real nitrate-contaminated wastewater confirms that the Cu NW/CF cathode maintained excellent denitrification efficiency over a 60-day period. This study offers a promising perspective on preventing electrode scaling in electrochemical wastewater treatment, paving the way for more efficient and sustainable practices.

Deciding on the priority of process parameters using the analytical hierarchy process in electrochemical wastewater treatment and investigation of paint wastewater treatability

In planning electrochemical treatment processes, it is thought that decision-making tools should be used in the selection of the main parameters that are likely to affect pollutant removal. According to detailed research in the literature, no previous study has systematically prioritized process parameters in electrochemical wastewater treatment using the analytical hierarchy process (AHP). In this study, published articles in the literature on the subject were used to determine which parameters were used in the treatment processes and with what frequency. Using the obtained results, the priorities of the process parameters were estimated with the help of AHP within the scope of the removal efficiencies and treatment cost criteria. According to the AHP analysis results, it was determined that the most effective parameters for both electrocoagulation and electrooxidation processes were pH (0.241), current density (0.171), voltage (0.171), conductivity (0.107), concentration (0.105) and reaction time (0.094). Four of the independent parameters were selected and treatability studies were carried out using both electrocoagulation (with Al electrode pair and Fe electrode pair) and electro oxidation (with Graphite electrode pair and Ti electrode pair) methods for different levels of each parameter. The pH, current density, voltage, and reaction time were chosen as independent parameters based on decision making process. Unit costs for removal of chemical oxygen demand with Al, Fe, graphite, and Ti electrodes were obtained as 1.05, 2.56, 0.074, and 14 USD per m3 wastewater, respectively. Unit costs for removal of color with Al, Fe, graphite, and Ti electrodes were obtained as 0.68, 1.20, 0.074, and 14 USD per m3 of wastewater, respectively. In addition, nine batch kinetic studies were conducted for optimum conditions obtained from pre-treatment studies with Al and Fe electrodes. Removal of chemical oxygen demand was achieved at 64 % with aluminum and iron electrodes at 40 and 70 min, respectively. The results obtained from kinetic studies showed that adsorption of organic substances fit the 2nd-order kinetic model and the correlation coefficient was 0.95 and 0.96 for aluminum and iron electrodes, respectively.

Electrochemical treatment of textile wastewater using electrodes from pyrolyzed rice husk

Rice husk char (RHC) electrodes were used for the first time in electrochemical treatment of textile wastewater. SEM analysis revealed RHC's porous structure, while TGA showed it decomposes in four stages and is stable up to 189 °C. BET analysis indicated a high surface area of 734 m2/g and a microporous structure with 11.7 Å pore diameter and 0.213 mL/g pore volume. RHC electrodes pyrolyzed at 700 °C for 2 h and placed 15 cm apart worked best in a 2 L batch reactor with methylene blue (MB) as the model pollutant and 6 g/L NaCl as the electrolyte. The process followed first-order kinetics, with fastest reaction at 100 mg/L initial MB. Reduced TOC and changed FTIR spectra confirmed MB breakdown. The batch system removed 85.8 % of dye from real textile wastewater in 150 min. In continuous flow, lower rates achieved higher efficiencies, up to 90 % at 0.45 L/h after 210 min. Although RHC electrodes had lower conductivity and strength than metal, they represent a sustainable, cost-effective alternative for electrochemical wastewater treatment.

Molybdenum oxide catalyst for wastewater treatment studied by faradaic efficiency

The measurements of gas volumes evolved during electrochemical wastewater treatment provide the information on the process faradaic efficiency. This work demonstrates how it enables identification of the water oxidation pathway (2 or 4 electron) in flow electrolysis process through the application of the formulae suggested in the study. This way, the real wastewater oxidation strength, i.e. production of hydrogen peroxide can be determined based on calculations. These provide more accurate results than direct measurements of accumulated hydrogen peroxide concentration after the electrolysis process, as its instability may lead to its immediate decomposition and false results. As an example provided in the paper, the application of MoO3 as a catalyst in the carbon composite electrode indicates almost no hydrogen peroxide detected after the process, whereas its oxidative properties owing to production of hydroxyradicals demonstrate complete decomposition of wastewater analogue (methylene blue). The calculations point to high production of H2O2. Using pure carbon material without the catalyst in the same experiment, decomposition occurs at much lower rate. The possible mechanisms behind the processes are discussed. The approach presented in the work can aid to efficient development of catalysts towards two-electron water oxidation.

Electrochemical Wastewater Treatment Technologies Through Life Cycle Assessment: A Review

AbstractElectrochemical wastewater treatment technologies are gaining attraction as sustainable alternatives for industrial and municipal wastewater management. This study conducts a comprehensive life cycle assessment to assess the environmental and economic sustainability of electrochemical methods such as electrocoagulation, electrooxidation, and electroreduction. By analyzing key stages, from raw material extraction to end‐of‐life disposal, the review aims to provide insight into their overall sustainability performance. The study also delves into environmental impact categories and utilization of methods used in quantifying the environmental implications. Moreover, a cost structure analysis and cost‐effectiveness evaluation offer insights into the economic viability of these technologies. Despite facing challenges like high initial costs and regulatory constraints, electrochemical technologies demonstrate competitive advantages in treatment efficiency and energy savings. Collaborative efforts and supportive policy frameworks are deemed crucial for overcoming barriers and fostering the widespread adoption of electrochemical technologies, thereby advancing sustainable wastewater management practices.

Influence of Different Proportions of the Addition of Electrocoagulated Metal Sludge (EMS) Obtained from Oily Wastewater Treatment on the Properties of Laboratory Bricks

Electrochemical wastewater treatment technologies are increasingly being used in practice, and the combination of electrocoagulation with advanced oxidation processes has been shown to increase treatment efficiency. The treatment of oily wastewater produces electrocoagulated metal sludge (EMS). In this work, the possibility of using different ratios of EMS produced during oily wastewater treatment was investigated. EMS was dried conventionally in an oven at 105 °C and used as a partial substitute for clay in the manufacture of laboratory bricks. The main research objectives of this study were to examine the possibility and justification of introducing EMS in brick production. The results show that an increase in the proportion of EMS in the manufacturing of bricks leads to a deterioration in the quality of the bricks. Bricks with an addition of 1 wt% and 5 wt% EMS showed the best properties. The loss on ignition (LOI), compressive strength, boiling water absorption and initial water absorption were determined at 5.7%; 49 N/mm2, 16%, 14 g/min/200 cm2, 15% for modified bricks with 1 wt% EMS and 6.3%, 48 N/mm2, 20%, 15 g/min/200 cm2 for modified brick with 5 wt%.

Engineering low-valent molybdenum sites in CoMoO4 nanosheets to boost electrochemical nitrogen-rich wastewater treatment

Electrochemical coupling nitrate-to-ammonia (NO3–-to-NH3) with urea oxidation reaction (UOR) is attractive for both energy-saving ammonia synthesis and comprehensive nitrogen-rich wastewater treatment. However, developing the efficient electrocatalyst that simultaneously promotes hydrogenation of NO3– and UOR is still challenging. Here, we engineered the porous CoMoO4 nanosheets with rich low-valent Mo sites (Mo(L)-CoMoO4-x) as a difunctional electrocatalyst for both NO3–-to-NH3 and UOR. The Mo(L)-CoMoO4-x displayed high Faradaic efficiency (93.33%) and selectivity (91.16%) for NO3–-to-NH3 and low potential (1.31 V vs. RHE) at 100 mA cm−2 toward UOR. Impressively, a low cell voltage of 1.83 V was needed for coupling UOR with NO3–-to-NH3 in two-electrode system. Mechanism study revealed that the introduction of low-valent Mo sites in CoMoO4 nanosheets accelerated the activation kinetics and multistep hydrogenation of NO3–, and also promoted the reconstruction of active CoOOH species for UOR, resulting the difunctional catalytic property for NO3–-to-NH3 and UOR.

Preparation of biochar-loaded nano zero-valent iron electrode material and its electrocatalytic degradation of p-nitrophenol

&lt;p&gt;Electrochemical treatment of wastewater containing p-nitrophenol (PNP) was carried out using a platinum electrode as an anode and biochar-loaded nano zero-valent iron material as the cathode. The prepared biochar loaded nano zero valent iron electrode materials were characterized and analyzed using SEM, XRD, and XPS. The experiment investigated the effects of current density, initial PNP concentration, electrolyte concentration, pH value, and other factors on the treatment effect of PNP. The results showed that the nZVI/BC electrode with an initial pH value of 7.0, a current density of 10mA/cm2, and an electrolyte of 1.5g/L anhydrous sodium sulfate was the optimal condition for degrading a PNP solution with an initial concentration of 20 mg/L. The PNP removal rate within 24 hours was 81.94%.BC@nZVI electrode has good stability and reusability.&lt;/p&gt;

Optimisation of treatment efficiency and effluent toxicity during carbamazepine degradation via electrochemical oxidation

The commercialisation of electrochemical advanced oxidation processes (eAOPs) as a method for removing recalcitrant pollutants from wastewater is currently limited due to the potential for the formation of toxic by-products. In this regard, this research comprised a comprehensive optimisation study aimed at finding a balance between minimising the toxicity effects observed via phytotoxicity assays and maximising the eAOP degradation efficiency under low energy requirements. To this end, carbamazepine (CBZ) was selected as the target pollutant in synthetic wastewater, and the operating conditions considered for optimisation were the nature of the anolyte (i.e., sulfate- or chloride-based), its concentration, and the current density applied. Together with the identification of the CBZ transformation products and their estimated toxicity based on the ECOSAR model, the optimum treatment was found to correspond to the degradation in 500 mg L−1 of a sulfate-based anolyte at a current density of 10 A m−2. These conditions led to the fewest and least toxic transformation products and favoured plant growth indices in phytotoxicity tests. Even if additional process improvements are required to reduce effluent toxicity, continuing such a multi-target optimisation approach can lead to innocuous electrochemical wastewater treatment.

Enhanced treatment of p-nitrophenol and coking wastewater through electrochemical and electrochemical-ozonation coupling process utilizing a novel Ti4O7 reactive electrochemical membrane anode

Organic pollutants in water could be removed by electrochemical treatment using a reactive electrochemical membrane (REM) with Magnéli phase Ti4O7, yet it is challenging to design suitable porosity to realize effective mass transfer and enhance the reactivity. Here, a novel Ti4O7 REM was prepared by a spark plasma sintering (SPS) method, which showed excellent electrochemical reactivity and mass transfer rate for organic pollutants in water. Compared to other Ti4O7 REMs, the novel Ti4O7 REM achieved a 140–9000-fold decrease in charge transfer resistance and a 5–110-fold increase in mass transfer rate. The p-nitrophenol in water can be completely removed in the REM system, with a maximum total organic carbon (TOC) removal rate of 85%. Then the REM system obtained an amazing removal rate of TOC (50.1%) and UV254 (89.6%) in the electrochemical treatment of real coking wastewater. In addition, to further enhance the removal efficiency, a coupled oxidation process with the novel Ti4O7 REM and O3 aeration was investigated. The TOC removal rate and energy consumption were 57.1% and 165.2 kWh (kg TOC)−1 at the optimal conditions within a short treating time. Our findings highlighted an innovative REM for a broad range of potential environmental applications.