Use of Electrooxidation as a Polishing Step for the Residual Water Obtained in a Solar Wastewater Treatment
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2023-09-19 |
| Journal | Journal of the Mexican Chemical Society |
| Authors | Eva Carina Tarango-Brito, Anabel Ramos-GarcĂa, Liliana Ivette Ăvila CĂłrdoba, Carlos Barrera-DĂaz |
| Institutions | Universidad AutĂłnoma del Estado de MĂ©xico |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: BDD Electrooxidation for Wastewater Polishing
Section titled âTechnical Documentation & Analysis: BDD Electrooxidation for Wastewater PolishingâThis document analyzes the research paper âUse of Electrooxidation as a Polishing Step for the Residual Water Obtained in a Solar Wastewater Treatment,â focusing on the application of Boron-Doped Diamond (BDD) electrodes, and connects the material requirements directly to 6CCVDâs advanced MPCVD diamond capabilities.
Executive Summary
Section titled âExecutive SummaryâThe research successfully demonstrates the efficacy of Boron-Doped Diamond (BDD) electrooxidation as a high-efficiency polishing step for concentrated wastewater residue containing Carmine Red dye.
- Material Validation: BDD electrodes were confirmed as the superior anode material due to their high oxygen overpotential, enabling the efficient generation of hydroxyl radicals (âąOH).
- Rapid Degradation: The electrooxidation process achieved extremely rapid Chemical Oxygen Demand (COD) reduction, lowering the COD concentration to below 1 mg/L in the residual water within just 5 minutes under optimal conditions.
- High Efficiency: Under the best tested conditions (pH 2.7, 22.2 mA cm-2), the process achieved a 91% COD removal efficiency in 30 minutes for the initial synthetic solution.
- Low Energy Footprint: The combined solar distillation and BDD polishing system is environmentally friendly, requiring a low energy consumption of 5 kWh L-1 to produce high-quality treated water.
- Optimal Parameters: Performance was maximized in acidic conditions (pH 2.7), which favors the formation of highly oxidative âąOH radicals on the BDD surface.
- Application: This methodology provides a robust, low-energy solution for the final treatment and mineralization of recalcitrant organic pollutants in industrial wastewater streams.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the experimental results, focusing on the BDD electrooxidation process parameters and performance metrics.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Anode Material | Boron-Doped Diamond (BDD) | N/A | Used for electrooxidation |
| Cathode Material | Stainless Steel | N/A | Counter electrode in the cell |
| Electrode Surface Area | 45 | cm2 | Total area of BDD and SS electrodes |
| Initial Dye Concentration | 25 | ppm | Carmine Red synthetic wastewater |
| Optimal pH (Acidic) | 2.7 | N/A | Condition favoring âąOH radical formation |
| Optimal Current Density (j) | 22.2 | mA cm-2 | Highest tested current density |
| COD Removal Efficiency (30 min, pH 2.7) | 91 | % | Achieved on initial synthetic solution |
| Time to COD < 1 mg/L (Residual Water) | 5 | minutes | Polishing step under optimal conditions |
| Energy Consumption (ECv) | 5 | kWh L-1 | Required for treatment under optimal conditions |
| Initial COD Concentration | 37 | mg/L | Before electrooxidation treatment |
| Final Turbidity (Treated Water) | 0 | UNT | Achieved after electrooxidation |
Key Methodologies
Section titled âKey MethodologiesâThe electrooxidation process was conducted as a polishing step following solar distillation/photocatalysis. The key steps and parameters for the electrochemical treatment are summarized below:
- Wastewater Source: Residual aqueous solution concentrated after solar distillation, containing concentrated dye and intermediate degradation products.
- Reactor Setup: A 500 mL glass cylinder reactor was used, containing 400 mL of wastewater solution, and maintained at room temperature with magnetic stirring for homogeneity.
- Electrode Configuration: The cell utilized two electrodes, a Boron-Doped Diamond (BDD) plate acting as the anode and a Stainless Steel cylinder acting as the cathode. Both electrodes had a surface area of 45 cm2.
- Power Application: A Direct Current (DC) power source was used to control the applied current, thereby controlling the current density (j).
- Parameter Optimization: The study evaluated two critical parameters for electrooxidation efficiency:
- pH: Tested at 6.2 and 2.7 (acidic).
- Current Density (j): Tested at 22.2 mA cm-2 and 16.6 mA cm-2.
- Optimal Conditions Selection: The best performance (highest COD removal) was achieved at pH 2.7 and a current density of 22.2 mA cm-2.
- Performance Analysis: Water quality was assessed using physicochemical tests including COD, pH, Conductivity, Turbidity, UV-Vis spectrophotometry, and IR spectrometry. Energy consumption per volume (ECv) was also calculated.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe successful implementation of this high-efficiency wastewater treatment relies fundamentally on the quality and customization of the Boron-Doped Diamond (BDD) electrodes. 6CCVD is uniquely positioned to supply the necessary materials and engineering support to replicate, scale, and optimize this research for industrial application.
| Research Requirement | 6CCVD Solution & Capability | Technical Advantage for Replication/Scale-Up |
|---|---|---|
| High-Performance BDD Anodes | Heavy Boron-Doped PCD Wafers (BDD) | Provides the highest oxygen overpotential, maximizing âąOH radical production for superior mineralization and rapid COD reduction (91% efficiency). |
| Electrode Size & Geometry | Custom Dimensions up to 125mm (PCD) | We supply BDD plates/wafers in custom sizes, easily accommodating the 45 cm2 requirement or scaling up to inch-size plates for pilot and industrial flow reactors. |
| Surface Finish | Polishing to Ra < 5nm (Inch-size PCD) | Ultra-smooth surfaces ensure uniform current distribution, prevent fouling, and maintain long-term electrode stability under high current density (22.2 mA cm-2). |
| Electrical Integration | Custom Metalization (Ti, Pt, Au, W) | We offer in-house metalization services to deposit robust, low-resistance contact layers (e.g., Ti/Pt/Au) necessary for reliable connection to the DC power supply. |
| BDD Film Thickness | SCD/PCD/BDD Films from 0.1”m to 500”m | We optimize BDD film thickness on conductive substrates (e.g., Niobium or Silicon) to balance electrochemical performance and material cost for large-scale deployment. |
| Global Logistics | Global Shipping (DDU default, DDP available) | Ensures rapid and secure delivery of custom BDD electrodes to research facilities and industrial sites worldwide. |
Engineering Support
Section titled âEngineering Supportâ6CCVDâs in-house PhD team specializes in the material science and electrochemical properties of diamond. We offer comprehensive engineering consultation to assist researchers and industrial partners with similar Advanced Oxidation Process (AOP) projects, including:
- Material Selection: Determining the optimal doping level and substrate choice for specific current density and pH requirements.
- Electrode Design: Assisting with the design and fabrication of custom-sized BDD electrodes for flow cells or scaled-up reactors.
- Performance Optimization: Providing insight into how diamond morphology (SCD vs. PCD) affects long-term stability and efficiency in aggressive acidic environments (pH 2.7).
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
Abstract. Dyes are widely used in many industrial operations for a variety of products; however, when wastewater is discharged without a treatment in rivers and lakes, severe environmental impacts are observed. In this work, the results of a solar wastewater treatment are presented. The solar treatment consists in parabolic heater coupled with a solar distiller which contains a ZnO plate that works as photocatalyst. Distilled water presents good characteristics; nevertheless, a residue that contains dye and intermediate products is also obtained. An electrooxidation treatment using boron-doped diamond electrodes (BDD), is applied at the residue as a polishing step. It was observed that wastewater quality improves when using an aqueous solution of pH 2.7 and a current density of 22.2 mA cm-2. Physicochemical test such as COD, and UV-Vis were used to evaluate the wastewater quality. It was found that 40 minutes are required to attain the improvement. This technology is environmental friendly since low energy is required (5 kW h L-1). Resumen. Los colorantes son ampliamente utilizados en la industria para una gran variedad de productos; cuando se descargan aguas residuales con dichos compuestos en rĂos o lagos, ocasionan severas afectaciones al medio ambiente. Este trabajo presenta los resultados obtenidos al someter agua sintĂ©tica a un proceso consistente en un calentador acoplado a un destilador solar que contiene un fotocatalizador. En dicho procedimiento se obtiene agua destilada de buena calidad, sin embargo, tambiĂ©n se genera un agua residual concentrada con presencia de colorante y productos intermediarios. A manera de pulimento se aplica la electrooxidaciĂłn empleando electrodos de diamante dopados con boro. Con las mejores condiciones: pH 2.7 y densidad de corriente de 22.2 mA cm-2, se encuentra que el agua residual presenta una notable mejorĂa en caracterĂsticas fisicoquĂmicas de DQO y espectroscopia UV-Vis. Se encontrĂł que es necesario un periodo de tiempo de 40 minutos para mejorar las caracterĂsticas del agua concentrada, lo cual hace que este proceso sea ambientalmente amigable, ya que requiere la aplicaciĂłn de poca energĂa (5kW h L-1).