Boron doped micro/nanocrystalline diamond electrodes used on the electrochemical flow reactor to degrade brilliant green
- PDF / 628,527 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 53 Downloads / 205 Views
Boron doped micro/nanocrystalline diamond electrodes used on the electrochemical flow reactor to degrade brilliant green dye William D. Toledo1, Lilian M. Silva1, Marta Santos1,2, André F. Sardinha1, Neidenêi G. Ferreira1. 1 Associated Laboratory of Sensors and Materials, National Institute for Space Research, São José dos Campos, SP, 12227-010, Brazil. 2 Fatec Pindamonhangaba, Pindamonhangaba, SP, 12445-010, Brazil. ABSTRACT A systematic study was performed concerning the production, characterization, and application of BDD and BDND films grown on Ti substrate to degrade brilliant green dye using an electrochemical flow reactor. Films were grown in a hot filament chemical vapour deposition (HFCVD) reactor using H2/CH4 (BDD) and H2/CH4/Ar (BDND) gas mixtures. Boron doping was performed by dissolution of B2O3 in methanol in the appropriate B/C ratio to obtain good conductive electrodes. The electrolysis was carried out using BDD/Ti and BDND/Ti as anode material analyzing the influence of different current densities and flow rates. During the electrolysis, aliquots of the treated solution were analyzed by UV-Vis and Total Organic Carbon (TOC) measurements. The electrode efficiencies were compared considering the color removal as well as the TOC mineralization in the end of each electrolysis. The absorption bands intensity from UV/Vis spectra clearly decreased up to their completely vanishing at current density of 100 mA/cm2 for both electrodes. These results were corroborated by TOC measurements where 50% of the organic material was removed. INTRODUCTION Traditional wastewater treatments encompass physical, chemical, and biological methodologies [1,2], which may present advantages or disadvantages depending on the total or partial degradation of the contaminant for the required application [3]. Presently, anaerobic membrane bioreactors [4] together with advanced oxidation processes (AOPs) [5] have driven great attention due to their potential of degradation and removal of a large spectrum of organic pollutants. Particularly, the interest in AOPs process is due to its high degradation capacity of a large variety of soluble contaminants. These methods are based on chemical, photochemical, photocatalytical or electrochemical production of hydroxyl radical (•OH). In this context, advanced electrochemical oxidation process (AEOP) is considered a powerful emergent technology for water remediation [6]. AEOPs can produce (•OH) from an electrochemical reaction using the cleanest agent, the electron, avoiding additional chemical agents for the treatment. Besides, this methodology is highly appropriated to degrade persistent organic compounds, such as azo-dyes and the choice of the anode material is a key step. In this work, BDD/Ti and BDND/Ti electrodes were produced, characterized, and applied in the brilliant green dye electrochemical degradation. BDD and BDND were grown in a HFCVD reactor, using H2/CH4 and H2/CH4/Ar mixtures, respectively. The electrolysis was carried out in an electrochemical reactor analyzing the influence
Data Loading...
