Degradation of gestodene (GES)–17α-ethinylestradiol (EE2) mixture by electrochemical oxidation

Evidence of the negative effects of several pharmaceutical molecules, such as hormones and steroids, on the environment can be observed throughout the world. This paper presents the results of the anodic oxidation of the mixture of gestodene steroid hormones and 17 α-ethinylestradiol present in aqueous medium. The tests were conducted in an undivided cell containing a working volume of 50 mL, using a Na2SO4 solution as support electrolyte and boron-doped diamond electrodes. The experiments were adjusted to the structure of a 33 factorial design. The evaluated factors were: support electrolyte concentration (0.02, 0.05, and 0.10 M), pH of the reaction media (2, 3, and 4), and current density (16, 32, and 48 mA cm−2). Under the optimum conditions (0.02 M Na2SO4, pH 4, and current density of 32 mA cm−2), the degradation of at least 93% of the initial concentration of gestodene and 17α-ethinylestradiol was reached in a reaction time of 5 and 10 min, respectively. The complete degradation of both molecules required 15 min of reaction. Under these conditions, the degradation profile of the pharmaceutical mixture as each one of the active ingredients, followed a pseudo-first order kinetic behavior (kmix = 0.0321, kGES = 0.4206, and kEE2 = 0.3209 min−1).

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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 ◽

10.3390/w12061686 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1686 ◽

Cited By ~ 1

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.

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Photochromism-Induced Amplification of Critical Current Density in Superconducting Boron-Doped Diamond with an Azobenzene Molecular Layer

ACS Applied Materials & Interfaces ◽

10.1021/am5074613 ◽

2014 ◽

Vol 7 (1) ◽

pp. 887-894 ◽

Cited By ~ 16

Author(s):

Keisuke Natsui ◽

Takashi Yamamoto ◽

Miku Akahori ◽

Yasuaki Einaga

Keyword(s):

Critical Current Density ◽

Critical Current ◽

Current Density ◽

Molecular Layer ◽

Boron Doped Diamond ◽

Boron Doped

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

Journal of Physics Communications ◽

10.1088/2399-6528/aab39f ◽

2018 ◽

Vol 2 (4) ◽

pp. 045015 ◽

Cited By ~ 1

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

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

Scientific Reports ◽

10.1038/s41598-019-51596-w ◽

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.

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

Water Science & Technology ◽

10.2166/wst.2019.040 ◽

2019 ◽

Vol 79 (5) ◽

pp. 921-928 ◽

Cited By ~ 3

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.

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Methiocarb Degradation by Electro-Fenton: Ecotoxicological Evaluation

Molecules ◽

10.3390/molecules25245893 ◽

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.

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Modulation of critical current density in polycrystalline boron-doped diamond by surface modification

physica status solidi (b) ◽

10.1002/pssb.201370559 ◽

2013 ◽

Vol 250 (9) ◽

Author(s):

Keisuke Natsui ◽

Takashi Yamamoto ◽

Takeshi Watanabe ◽

Yoichi Kamihara ◽

Yasuaki Einaga

Keyword(s):

Surface Modification ◽

Critical Current Density ◽

Critical Current ◽

Current Density ◽

Boron Doped Diamond ◽

Boron Doped

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Electrooxidation of Diclofenac in Synthetic Pharmaceutical Wastewater Using an Electrochemical Reactor Equipped with a Boron Doped Diamond Electrode

Journal of the Mexican Chemical Society ◽

10.29356/jmcs.v58i3.136 ◽

2017 ◽

Vol 58 (3) ◽

Cited By ~ 1

Author(s):

Gabriela Coria ◽

José L. Nava ◽

Gilberto Carreño

Keyword(s):

Energy Consumption ◽

Current Density ◽

Electrochemical Reactor ◽

Pharmaceutical Wastewater ◽

Boron Doped Diamond ◽

Linear Flow ◽

Diamond Electrode ◽

Boron Doped ◽

Boron Doped Diamond Electrode ◽

Set Up

This paper deals with the degradation of diclofenac by electrochemical oxidation in NaClO4 medium at neutral pH using a FM01-LC reactor equipped with a boron doped diamond electrode (BDD). Microelectrolysis studies were carried out to find the current density domain where hydroxyl radical (•OH) formation is favored, 10 ≤ j ≤ 20 mA cm-2. Electrolysis experiments at mean linear flow velocities of 14.6 ≤ u ≤ 58.4 cm s-1 were performed. The experimental set-up achieved 100% diclofenac mineralization with 78% current efficiency and energy consumption of 2.54 kWh m-3 at j = 15 mA cm-2 and u=29.2 cm s-1.

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

Water Science & Technology ◽

10.2166/wst.2020.176 ◽

2020 ◽

Vol 81 (5) ◽

pp. 925-935 ◽

Cited By ~ 1

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.

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Advanced electrochemical treatment of real biotreated petrochemical wastewater by boron doped diamond anode: performance, kinetics, and degradation mechanism

Water Science & Technology ◽

10.2166/wst.2020.387 ◽

2020 ◽

Vol 82 (4) ◽

pp. 773-786

Author(s):

Hao Li ◽

Xinmou Kuang ◽

Congping Qiu ◽

Xiaolan Shen ◽

Botao Zhang ◽

...

Keyword(s):

Current Density ◽

Ph Value ◽

Degradation Products ◽

Degradation Mechanism ◽

Cod Removal ◽

Agitation Rate ◽

Petrochemical Wastewater ◽

Boron Doped Diamond ◽

Boron Doped ◽

A Current

Abstract Petrochemical wastewater is difficult to process because of various types of pollutants with high toxicity. With the improvement in the national discharge standard, traditional biochemical treatment methods may not meet the standards and further advanced treatment techniques would be required. In this study, electrochemical oxidation with boron doped diamond (BDD) anode as post-treatment was carried out for the treatment of real biotreated petrochemical wastewater. The effects of current density, pH value, agitation rate, and anode materials on chemical oxygen demand (COD) removal and current efficiency were studied. The results revealed the appropriate conditions to be a current density of 10 mA·cm−2, a pH value of 3, and an agitation rate of 400 rpm. Moreover, as compared with the graphite electrode, the BDD electrode had a higher oxidation efficiency and COD removal efficiency. Furthermore, GC-MS was used to analyze the final degradation products, in which ammonium chloride, formic acid, acetic acid, and malonic acid were detected. Finally, the energy consumption was estimated to be 6.24 kWh·m−3 with a final COD of 30.2 mg·L−1 at a current density of 10 mA·cm−2 without the addition of extra substances. This study provides an alternative for the upgrading of petrochemical wastewater treatment plants.

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