Performance Evaluation of Active and Non-active Electrodes for Doxorubicin Electro-oxidation
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2020-06-02 |
| Journal | KnE Engineering |
| Authors | Eric de Souza Gil, Emily Kussmaul Gonçalves Moreno, Luane Ferreira Garcia, JosÊ J. Linares |
| Institutions | Universidade Federal de GoiĂĄs, Universidade de BrasĂlia |
| Citations | 4 |
| Analysis | Full AI Review Included |
Executive Summary
Section titled âExecutive SummaryâThis study evaluates the efficiency and energy consumption of active (AE) and non-active (NAE) electrodes for the electro-oxidation (EO) of Doxorubicin (DOX), a critical micropollutant in hospital effluents.
- Core Finding: The Non-Active Electrode (NAE), Boron-Doped Diamond (BDD), demonstrated superior performance compared to the Active Electrode (AE), AuO-TiO2@graphite.
- Degradation Kinetics: BDD achieved complete (100%) DOX degradation in 20 minutes, while the nanostructured AuO-TiO2@graphite required 40 minutes for the same result.
- Energy Efficiency: BDD exhibited significantly lower energy consumption (0.462 kWh m-3), making it 2.4 times more energy efficient than the AE (1.12 kWh m-3).
- Mechanism: The superior performance of BDD is attributed to its high oxygen evolution potential (up to 2.6 V/EPH), which facilitates the formation of highly reactive BDD(â˘OH) radicals and minimizes parasitic reactions.
- Electrolyte Role: The use of 10 mmol L-1 NaCl supporting electrolyte was crucial, promoting degradation via the generation of powerful chlorinated oxidants (e.g., hypochlorous acid).
- Conclusion: Both EO methods are viable for antineoplastic drug removal, but BDD is the preferred technology due to its faster kinetics and lower operational energy cost.
Technical Specifications
Section titled âTechnical Specificationsâ| Parameter | Value | Unit | Context |
|---|---|---|---|
| Target Pollutant | Doxorubicin (DOX) | N/A | Antineoplastic drug micropollutant |
| Initial DOX Concentration | 1.25 | mmol L-1 | Standard solution concentration |
| Supporting Electrolyte | 10 | mmol L-1 | NaCl (promotes chlorinated oxidants) |
| Applied Voltage (AE) | 5.0 | V | Controlled by tensiometer (AuO-TiO2@graphite) |
| Applied Current (NAE) | 1 | mA | Galvanostatic mode (BDD) |
| BDD Degradation Time (100% removal) | 20 | min | Non-Active Electrode (NAE) |
| AuO-TiO2@graphite Degradation Time (100% removal) | 40 | min | Active Electrode (AE) |
| BDD Energy Consumption (EC) | 0.462 | kWh m-3 | Energy efficiency for 100% removal |
| AuO-TiO2@graphite EC | 1.12 | kWh m-3 | Energy efficiency for 100% removal |
| BDD Geometric Area | 78.5 | cm2 | Filter press reactor configuration |
| BDD Electrode Gap | 2 | mm | Distance between anode and cathode |
| BDD O2 Evolution Potential | 2.2 - 2.6 | V/EPH* | High potential window (V vs. standard hydrogen electrode) |
| â˘OH Standard Reduction Potential | 2.80 | V/EPH | High oxidation power for non-selective decomposition |
Key Methodologies
Section titled âKey MethodologiesâThe electrochemical remediation was conducted using two distinct setups for the Active and Non-Active electrodes, with performance quantified by degradation time and energy consumption (EC).
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Sample Preparation:
- Doxorubicin hydrochloride solutions were prepared at 1.25 mmol L-1.
- 10 mmol L-1 NaCl was added as the supporting electrolyte to enhance oxidation via chlorinated species.
-
Active Electrode (AE) Treatment (AuO-TiO2@graphite):
- Setup: 5 mL capacity electrochemical cell. Anode: AuO-TiO2@graphite. Cathode: Pt wire.
- Operation: Applied voltage of 5.0 V (DC power supply HF-30035).
- Monitoring: DOX degradation tracked using UV-Vis spectrophotometry (190 to 800 nm).
-
Non-Active Electrode (NAE) Treatment (BDD):
- Setup: Filter press electrochemical reactor (DiaCleanÂŽ, WaterDiam). Anode: Commercial BDD (78.5 cm2). Cathode: AISI 304 stainless steel (2 mm gap).
- Operation: Galvanostatic mode (1 mA applied current) with a flow solution volume of 1000 mL and a flow rate of 400 mL min-1.
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Performance Calculation:
- Degradation percentage (% removal) was measured at various time intervals (up to 120 minutes).
- Energy Consumption (EC) was calculated using the formula: EC(kWh m-3) = (Ecell * I * t) / Vreactor, accounting for average cell voltage (Ecell), applied current (I), electrolysis time (t), and solution volume (Vreactor).
Commercial Applications
Section titled âCommercial ApplicationsâThe findings support the implementation of Boron-Doped Diamond (BDD) electrodes in advanced oxidation processes (AOPs) for environmental remediation, particularly where high stability and efficiency are required.
- Wastewater Treatment (Hospital & Pharmaceutical Effluents):
- Targeted removal of persistent and toxic antineoplastic drugs (e.g., DOX, Methotrexate, Cyclophosphamide) that are resistant to conventional biological treatment.
- Achieving high removal percentages (100%) in short treatment times (20 minutes).
- Industrial Water Recycling:
- Application in agroindustrial and textile effluents containing complex organic compounds, leveraging the non-selective oxidation power of BDD(â˘OH) radicals.
- Electrochemical Reactor Design:
- Development of compact, high-throughput filter press reactors utilizing BDD anodes for efficient, low-energy water decontamination.
- Sustainable Remediation Technology:
- Implementation of environmentally compatible methods that avoid the use of polluting chemical compounds, aligning with green chemistry principles.
View Original Abstract
Electrochemical remediation is an innovative technique that utilizes electro-oxidation reactions to degrade micropollutants such as doxorubicin (DOX) that is a drug widely used to treat many types of cancer, and it is present in hospital effluents. The aim of this work is to evaluate the efficiency of active and non-active electrodes in DOX degradation during electrochemical treatments. AuO-TiO2@graphite, a nanostructured electrode, and BDD, a commercial electrode, were used as active and non-active electrodes respectively. DOX treatments were realized at concentration of 1.25 mmol L-1 in medium with 10 mmol L-1 NaCl as support electrolyte. Studies were realized in 5 V of voltage source. Results: The treatment of DOX with BDD promoted 100% of DOX degradation in 20 min, while the same result was obtained for the AuO-TiO2@graphite in 40 min of treatment. Also, the modified electrode presented an energy expenditure of 1.12 kWh m-3 and the BDD achieved 0.462 kWh m-3. Thus, the active and non-active electrodes were efficient to promote DOX degradation, and the BDD, the non-active electrode demonstrated a better performance. Keywords: Eletro-Oxidadion, Modified Graphite Anodes, BDD, Doxorubicin, Micropollutants