scholarly journals Electro-activated persulfate oxidation of malachite green by boron-doped diamond (BDD) anode: effect of degradation process parameters

2020 ◽  
Vol 81 (5) ◽  
pp. 925-935 ◽  
Author(s):  
Dongtian Miao ◽  
Guoshuai Liu ◽  
Qiuping Wei ◽  
Naixiu Hu ◽  
Kuangzhi Zheng ◽  
...  
Keyword(s):  
Malachite Green ◽  
Current Density ◽  
Degradation Process ◽  
Organic Content ◽  
Boron Doped Diamond ◽  
Persulfate Oxidation ◽  
Bdd Anode ◽  
Toc Removal ◽  
Boron Doped ◽  
Activated Persulfate

Abstract In this paper, boron-doped diamond (BDD) electro-activated persulfate was studied to decompose malachite green (MG). The degradation results indicate that the decolorization performance of MG for the BDD electro-activated persulfate (BDD-EAP) system is 3.37 times that of BDD electrochemical oxidation (BDD-EO) system, and BDD-EAP system also exhibited an enhanced total organic content (TOC) removal (2.2 times) compared with BDD-EO system. Besides, the degradation parameters such as persulfate concentration, current density, and pH were studied in detail. In a wider range of pH (2–10), the MG can be efficiently removed (>95%) in 0.02 M persulfate solution with a low current density of 1.7 mA/cm2 after 30 min. The BDD-EAP technology decomposes organic compounds without the diffusion limitation and avoids pH adjustment, which makes the EO treatment of organic wastewater more efficient and more economical.

scholarly journals Anodic oxidation of Bisphenol A (BPA) by different dimensionally stable (DSA) electrodes

2021 ◽  
Author(s):  
Orhan T. Can ◽  
Muhammed M. Tutun ◽  
Ramazan Keyikoglu
Keyword(s):  
Bisphenol A ◽  
Current Density ◽  
Specific Energy Consumption ◽  
Mixed Metal Oxide ◽  
Operational Parameters ◽  
Boron Doped Diamond ◽  
Bdd Anode ◽  
Toc Removal ◽  
Boron Doped ◽  
A Current

Abstract Bisphenol A (BPA) is a known endocrine disrupter and was detected in surface waters. We investigated the mineralization of BPA by electrochemical oxidation. Six different types of electrodes including the boron-doped diamond (BDD), platinum (Pt), and mixed metal oxide (MMO) electrodes; RuO2-IrO2, RuO2-TiO2, IrO2-Ta2O5, and Pt-IrO2 were compared as the anode material. Total organic carbon (TOC) was performed to monitor the mineralization efficiency of BPA. BDD achieved 100% BPA mineralization efficiency in 180 min and at a current density of 125 mA/cm2. Whereas the TOC removal efficiency of Pt was 60.9% and the efficiency of MMO electrodes ranged between 48 and 54%. BDD exhibited much lower specific energy consumption (SEC), which corresponds to a lower energy cost (63.4 $/kg TOC). The effect of operational parameters showed that the BDD anode was much more affected by the current density, initial BPA concentration, and electrolyte concentration than the other parameters such as the stirring speed and interelectrode distance.

Electro-oxidation of landfill leachate using boron-doped diamond: role of current density, pH and ions

2019 ◽  
Vol 79 (5) ◽  
pp. 921-928 ◽  
Author(s):  
F. Agustina ◽  
A. Y. Bagastyo ◽  
E. Nurhayati
Keyword(s):  
Current Density ◽  
Organic Content ◽  
Cod Removal ◽  
Boron Doped Diamond ◽  
Leachate Treatment ◽  
Ammonium Removal ◽  
Boron Doped ◽  
Wide Range ◽  
Electro Oxidation

Abstract Electro-oxidation using a boron-doped diamond (BDD) anode can be used as an alternative to leachate treatment. Aside from the hydroxyl radical, BDDs are capable of generating chloride and sulfate radical species that play significant roles in the oxidation of pollutants. This research investigated the role of Cl−:SO42− ions at molar ratios of 237:1, 4:1 and 18:1, and the influence of applied current density (i.e. 50, 75 and 100 mA cm−2) on the removal of organic and ammonium contaminants. The results show that current density had considerable effects on chemical oxygen demand (COD) and colour removal, while ion composition of Cl−:SO42− at pH 3, 5 and 8.5 (original pH) gave different effects on COD and ammonium removal. The pH had a significant effect on the COD removal at the ratio of 237:1, but showed no dramatic effect at the ratio of 18:1, giving ∼40% of COD removal at all pHs tested. This indicates that electro-oxidation at the ratio of 18:1 could be effectively conducted at a wide range of pH. Furthermore, the optimum ammonium removal was obtained at pH 8.5 with the ratio of 237:1. This process was found to be ineffective in increasing the biodegradability index of the leachate; instead, it exhibited mineralization of organic content.

Electro-Fenton for control and removal of micropollutants – process optimization and energy efficiency

2016 ◽  
Vol 74 (9) ◽  
pp. 2068-2074 ◽  
Author(s):  
E. Mousset ◽  
Z. Wang ◽  
O. Lefebvre
Keyword(s):  
Energy Efficiency ◽  
Current Density ◽  
Cost Effective ◽  
Aeration Rate ◽  
Carbon Cloth ◽  
Boron Doped Diamond ◽  
Bdd Anode ◽  
Boron Doped ◽  
Low Energy Consumption ◽  
Order Of Magnitude

The removal of micropollutants is an important environmental and health issue. Electro-Fenton offers an electrochemical advanced treatment that is particularly effective for the breakdown of aromatic contaminants. Due to the wide variety of chemicals, it is preferable to analyze model contaminants, such as phenol, when optimizing and assessing the efficacy of a novel treatment process. In this study, we therefore made use of innovative types of electrode material and optimized operating parameters (current density and aeration rate) for the removal of phenol by electro-Fenton, with a view to maximize the energy efficiency of the process. By determining the best current density (1.25 mA cm−2), frequency of aeration (continuous) and by using a boron-doped diamond (BDD) anode, it was possible to achieve over 98.5% phenol (1 mM) removal within 1.5 h. BDD further outcompeted platinum as anode material in terms of mineralization rate and yield, and displayed low energy consumption of 0.08 kWh (g-TOC)−1, about one order of magnitude lower than other advanced oxidation processes, such as UV/TiO2 and UV/O3. Furthermore, a carbon cloth anode proved even more cost-effective than BDD if the end goal is the removal of phenol by electro-Fenton instead of complete mineralization.

scholarly journals Electro-Fenton, UVA Photoelectro-Fenton and Solar Photoelectro-Fenton Treatments of Organics in Waters Using a Boron-Doped Diamond Anode: A Review

2017 ◽  
Vol 58 (3) ◽  
Author(s):  
Enric Brillas
Keyword(s):  
Degradation Process ◽  
Anode Surface ◽  
Industrial Chemicals ◽  
Decay Kinetics ◽  
Boron Doped Diamond ◽  
Stirred Tank Reactors ◽  
Bdd Anode ◽  
Fenton’S Reaction ◽  
Electrochemical Advanced Oxidation Processes ◽  
Boron Doped

<p>The characteristics and applications of electrochemical advanced oxidation processes (EAOPs) like electro-Fenton (EF), UVA photoelectro-Fenton (PEF) and solar PEF (SPEF) with a boron-doped diamond (BDD) anode are reviewed. Their oxidative properties are based on the attack of <sup>•</sup>OH formed at the anode surface and in the medium from Fenton’s reaction between cathodically generated H<sub>2</sub>O<sub>2</sub> and added Fe<sup>2+</sup>. The illumination with UVA light in PEF and sunlight in SPEF enhances the degradation process due to the photolysis of complexes of Fe(III) with generated carboxylic acids. Examples on the removal of industrial chemicals, pesticides, dyes and pharmaceuticals by these EAOPs using bench-scaled stirred tank reactors and pre-pilot plants are described. The influence of experimental variables on the mineralization and energetic parameters is detailed. The decay kinetics of pollutants and the evolution of intermediates are discussed. The SPEF process shows the best performance, being the most potent EAOP tested.</p>

scholarly journals Fate of Diclofenac and Its Transformation and Inorganic By-Products in Different Water Matrices during Electrochemical Advanced Oxidation Process Using a Boron-Doped Diamond Electrode

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1686 ◽  
Author(s):  
Carolin Heim ◽  
Mohamad Rajab ◽  
Giorgia Greco ◽  
Sylvia Grosse ◽  
Jörg E. Drewes ◽  
...  
Keyword(s):  
Current Density ◽  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
Early Stage ◽  
Advanced Oxidation ◽  
Target Compound ◽  
Duration Of Treatment ◽  
Boron Doped Diamond ◽  
Boron Doped ◽  
By Products

The focus of this study was to investigate the efficacy of applying boron-doped diamond (BDD) electrodes in an electrochemical advanced oxidation process, for the removal of the target compound diclofenac (DCF) in different water matrices. The reduction of DCF, and at the same time the formation of transformation products (TPs) and inorganic by-products, was investigated as a function of electrode settings and the duration of treatment. Kinetic assessments of DCF and possible TPs derived from data from the literature were performed, based on a serial chromatographic separation with reversed-phase liquid chromatographyfollowed by hydophilic interaction liquid chromatography (RPLC-HILIC system) coupled to ESI-TOF mass spectrometry. The application of the BDD electrode resulted in the complete removal of DCF in deionized water, drinking water and wastewater effluents spiked with DCF. As a function of the applied current density, a variety of TPs appeared, including early stage products, structures after ring opening and highly oxidized small molecules. Both the complexity of the water matrix and the electrode settings had a noticeable influence on the treatment process’s efficacy. In order to achieve effective removal of the target compound under economic conditions, and at the same time minimize by-product formation, it is recommended to operate the electrode at a moderate current density and reduce the extent of the treatment.

scholarly journals On the Role of the Cathode for the Electro-oxidation of Perfluorooctanoic Acid

2020 ◽  
Author(s):  
Alicia Garcia-Costa ◽  
André Savall ◽  
Juan A. Zazo ◽  
Jose A. Casas ◽  
Karine Groenen Serrano
Keyword(s):  
Electrochemical Techniques ◽  
High Strength ◽  
Perfluorooctanoic Acid ◽  
Reduction Reaction ◽  
Adsorbed Hydrogen ◽  
Boron Doped Diamond ◽  
Bdd Anode ◽  
Boron Doped ◽  
Initial Ph

Perfluorooctanoic acid (PFOA), C7F15COOH, has been widely employed over the past fifty years, causing an environmental problem due to its dispersion and low biodegradability. Furthermore, the high stability of this molecule, conferred by the high strength of the C-F bond makes it very difficult to remove. In this work, electrochemical techniques are applied for PFOA degradation in view to study the influence of the cathode on defluorination. For this purpose, boron doped diamond (BDD), Pt, Zr and stainless steel have been tested as cathodes working with BDD anode at low electrolyte concentration (3.5 mM) to degrade PFOA at 100 mg/L. Among these cathodic materials, Pt improves the defluorination reaction. The electro-degradation of a PFOA molecule starts by a direct exchange of one electron at the anode and then follows a complex mechanism involving reaction with hydroxyl radicals and adsorbed hydrogen on the cathode. It is assumed that Pt acts as an electrocatalyst, enhancing PFOA defluorination by the reduction reaction of perfluorinated carbonyl intermediates on the cathode. The defluorinated intermediates are then more easily oxidized by HO&bull; radicals. Hence, high mineralization (xTOC: 76.1%) and defluorination degrees (xF-: 58.6%) were reached with Pt working at current density j = 7.9 mA/cm2. This BDD-Pt system reaches a higher efficiency in terms of defluorination for a given electrical charge than previous works reported in literature. Influence of the electrolyte composition and initial pH are also explored.

scholarly journals Flux pinning and improved critical current density in superconducting boron doped diamond films

2018 ◽  
Vol 2 (4) ◽  
pp. 045015 ◽  
Author(s):  
Dinesh Kumar ◽  
Shibnath Samanta ◽  
K Sethupathi ◽  
M S Ramachandra Rao
Keyword(s):  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Flux Pinning ◽  
Diamond Films ◽  
Boron Doped Diamond ◽  
Boron Doped

scholarly journals Single-crystalline boron-doped diamond superconducting quantum interference devices with regrowth-induced step edge structure

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Taisuke Kageura ◽  
Masakuni Hideko ◽  
Ikuto Tsuyuzaki ◽  
Aoi Morishita ◽  
Akihiro Kawano ◽  
...  
Keyword(s):  
Critical Current Density ◽  
Josephson Junction ◽  
Current Density ◽  
Quantum Interference ◽  
Boron Doped Diamond ◽  
Edge Structure ◽  
Single Crystalline ◽  
Superconducting Quantum Interference Devices ◽  
Boron Doped ◽  
Crystalline Boron

Abstract Superconducting quantum interference devices (SQUIDs) are currently used as magnetic flux detectors with ultra-high sensitivity for various applications such as medical diagnostics and magnetic material microstructure analysis. Single-crystalline superconducting boron-doped diamond is an excellent candidate for fabricating high-performance SQUIDs because of its robustness and high transition temperature, critical current density, and critical field. Here, we propose a fabrication process for a single-crystalline boron-doped diamond Josephson junction with regrowth-induced step edge structure and demonstrate the first operation of a single-crystalline boron-doped diamond SQUID above 2 K. We demonstrate that the step angle is a significant parameter for forming the Josephson junction and that the step angle can be controlled by adjusting the microwave plasma-enhanced chemical vapour deposition conditions of the regrowth layer. The fabricated junction exhibits superconductor–weak superconductor–superconductor-type behaviour without hysteresis and a high critical current density of 5800 A/cm2.

scholarly journals Methiocarb Degradation by Electro-Fenton: Ecotoxicological Evaluation

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5893
Author(s):  
Faléstine Souiad ◽  
Ana Sofia Rodrigues ◽  
Ana Lopes ◽  
Lurdes Ciríaco ◽  
Maria José Pacheco ◽  
...  
Keyword(s):  
Current Density ◽  
Iron Concentration ◽  
Model Organism ◽  
Anodic Current Density ◽  
Applied Current ◽  
Boron Doped Diamond ◽  
Applied Current Density ◽  
Toxic Units ◽  
Boron Doped ◽  
Ecotoxicological Evaluation

This paper studies the degradation of methiocarb, a highly hazardous pesticide found in waters and wastewaters, through an electro-Fenton process, using a boron-doped diamond anode and a carbon felt cathode; and evaluates its potential to reduce toxicity towards the model organism Daphnia magna. The influence of applied current density and type and concentration of added iron source, Fe2(SO4)3·5H2O or FeCl3·6H2O, is assessed in the degradation experiments of methiocarb aqueous solutions. The experimental results show that electro-Fenton can be successfully used to degrade methiocarb and to reduce its high toxicity towards D. magna. Total methiocarb removal is achieved at the applied electric charge of 90 C, and a 450× reduction in the acute toxicity towards D. magna, on average, from approximately 900 toxic units to 2 toxic units, is observed at the end of the experiments. No significant differences are found between the two iron sources studied. At the lowest applied anodic current density, 12.5 A m−2, an increase in iron concentration led to lower methiocarb removal rates, but the opposite is found at the highest applied current densities. The highest organic carbon removal is obtained at the lowest applied current density and added iron concentration.

Sign in / Sign up

Export Citation Format

Share Document