Degrading a mixture of three textile dyes using photo-assisted electrochemical process with BDD anode and O₂–diffusion cathode

• Published in: Environmental science and pollution research international 2014, Vol.21 (14), p.8543-8554
• Main Authors: Khataee, Alireza, Safarpour, Mahdie, Vahid, Behrouz, Akbarpour, Amaneh
• Format: Article
• Language: English
• Subjects: analysis of variance; Aquatic Pollution; aqueous solutions; Atmospheric Protection/Air Quality Control/Air Pollution; Azo Compounds - chemistry; Azo Compounds - radiation effects; Azo dyes; Benzenesulfonates - chemistry; Benzenesulfonates - radiation effects; Boron; Boron - chemistry; Calibration; Carbon; carbon nanotubes; Coloring Agents - chemistry; Coloring Agents - radiation effects; Decolorization; Diamond - chemistry; Diffusion; Dyes; Earth and Environmental Science; Ecotoxicology; Efficiency; Electrochemical Advanced Oxidation Processes for Removal of Toxic/Persistent Organic Pollutants from Water; Electrochemistry; Electrodes; Environment; Environmental Chemistry; Environmental Health; Experiments; Mineralization; Nanotechnology; Nanotubes; Oxidation; Oxygen - chemistry; Persistent organic pollutants; Pollutants; Regression analysis; Studies; Textile Industry; Textile industry wastewaters; Ultraviolet Rays; Variance analysis; Waste Disposal, Fluid - methods; Waste materials; Waste Water Technology; wastewater; Water Management; Water Pollutants, Chemical - chemistry; Water Pollutants, Chemical - radiation effects; Water pollution; Water Pollution Control
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-014-2776-0

In this paper, degradation of a mixture of three azo dyes was studied by the photo-assisted electrochemical process using an O₂-diffusion cathode containing carbon nanotubes and boron-doped diamond (BDD) anode. The concentration of three textile dyes (C.I. Acid Orange 8 (AO8), C.I. Acid Orange 10 (AO10), and C.I. Acid Orange 12 (AO12)) was determined simultaneously despite the severe overlap of their spectra. For this purpose, partial least square (PLS), as a multivariate calibration method, was utilized based on recording UV–Vis spectra during the decolorization process. Moreover, the central composite design was used for the modeling of photo-assisted electrochemical decolorization of the aqueous solutions containing three dyes. The investigated parameters were the initial concentration of three dyes, applied current and reaction time. Analysis of variance (ANOVA) revealed that the obtained regression models match the experimental results well with R (Khataee et al. 2010, Clean-Soil Air Water 38 (1):96–103, 2010) of 0.972, 0.971, and 0.957 for AO8, AO10, and AO12, respectively. Three-dimensional surface and contour plots were applied to describe the relation between experimental conditions and the observed response. The results of TOC analysis confirmed good ability of proposed photo-assisted electrochemical process for degradation and mineralization of textile industry wastewater.