Electrochemical degradation of Mordant Blue 13 azo dye using boron-doped diamond and dimensionally stable anodes: influence of experimental parameters and water matrix

Abstract

In this work, the electrooxidation as environmentally clean technology has been studied to the degradation of Mordant Blue 13 azo dye (MB13) using boron-doped diamond (p-Si/BDD) and oxide ruthenium titanium (Ti/RuTiO (DSA)) anodes in various water matrices: distilled water (DW), hot tap water (HTW), and simulated wastewaters with (SWS) and without surfactant (SW). The influence of experimental parameters, such as current density, initial dye concentration, electrolysis time/specific charge, and pH on the MB13 degradation rate, current efficiency, and energy consumption, has been determined. The enhanced rate of both color and chemical oxygen demand (COD) removal in sulfate aqueous solutions with BDD was observed, which indicates that sulfate (SO) radicals along with OH ones might be responsible for the degradation process. The MB13 decolorization process obeyed a pseudo-first-order reaction kinetics with the apparent rate constant from 7.36 × 10 min to 4.39 × 10 min for BDD and from 9.2 × 10 min to 2.11 × 10 min for DSA depending on the electrolysis conditions. The effect of water matrix on the decolorization and COD removal efficiency has been evaluated. Inorganic ions, mordant salt, and surfactant contained in simulated effluents decelerated the COD decay compared to DW and HTW for the both anodes; meanwhile, they differently affected the discoloration process. A comparison of the specific energy consumption for each electrocatalytic material under different experiment conditions has been made. The BDD electrode was more efficient than the DSA to oxidize the MB13 dye in all kinds of water.

Electrochemical oxidation of butyl paraben on boron doped diamond in environmental matrices and comparison with sulfate radical-AOP

“…In another study, Murugananthan et al (2008) found that bisphenol A (BPA) oxidation was a currentcontrolled process and occurred faster at greater current densities. In the study of Kenova et al (2018), the decolorization of Mordant Blue 13 dye followed exponential decay with k app increasing with increasing applied current density. According to the authors, a remarkable increase in the dye removal rate at higher current density was due to the formation of additional radicals and other oxidizing species, (e.g.…”

“…organics, inorganics and microorganisms) for the precious oxidant species, as well as (in the case of heterogeneous processes) for the active sites of the catalysts/activators . In the study of Kenova et al (2018), on the electrooxidation of Mordant Blue 13 azo dye in different water matrices, both electrode material and water matrix parameters have been reported to significantly affect COD removal and dye decolorization.…”

Disinfection of Escherichia coli by a Reactive Electrochemical Membrane System Involving Activated Carbon Fiber Cloth (ACFC)

“…A ring-shaped rubber separator of 1.25-cm thickness was placed between the anode and cathode. The MMO grid is made of titanium coated with iridium-ruthenium oxide, which is known as a dimensionally stable anode (DSA) material and has been widely used in water treatment applications [22,23]. The MMO grids were used in the REM device both as a contactor on the anode and as the cathode because of their good conductivity and stability.…”

“…This suggests that hydroxyl radicals were mainly produced by ACFC rather than the MMO grid in the REM device. The MMO grid is coated with iridium-ruthenium oxide, which is known to be a material that facilitates anodic water oxidation without effective •OH production [23,33]. The moderate disinfection effect of REM without an ACFC layer as shown in Figure 2 may have resulted from ROS other than •OH, such as hydrogen peroxide, that were formed during water oxidation.…”

Anion Effect on the Electropolymerization Reaction of Metanil Yellow in Aqueous Media and Characterization of Polymer Films

“…Metanil Yellow is a toxic material for animals and human beings having mutagenic properties therefore its degradation is also a significant research interest. Many publications are found concerning the chemical and electrochemical destruction of azo dyes especially Metanil Yellow [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24].…”