Decolorization of reactive blue 171 dye using ozonation and UV/H₂O₂ and elucidation of the degradation mechanism

Abstract

In this report, the degradation of a commercially important dye C. I. Reactive Blue 171 (RB 171) has been investigated using peroxidation under UV light and ozone. The effect of operational conditions such as the dye concentration, operating pH and use of the oxidants such as ozone and UV/H2O2 was studied. Complete decolorization of RB 171 (50 mg/L) was obtained using ozonation, while UV/H2O2 showed poor decolorization efficiency. The COD removal by ozone was fair enough at 33%, whereas with UV/H2O2 it was lower than 2%. Characterization using TLC, FTIR and HPLC indicated degradation of the organic bonds of the dye. To the best of our knowledge, for the first time a possible fate of metabolism of intact dye molecule by ozone has been proposed using GC/MS analysis, which showed the production of benzene and aliphatic/aromatic sulfonate derivatives. Phytotoxicity studies revealed extensive reduction in toxicity of RB 171 with ozone. It may be concluded that the ozonation is a promising way of rapid decolorization along with effective mineralization. © 2015 American Institute of Chemical Engineers Environ Prog, 34: 1652–1661, 2015

Elucidation of degradation mechanism of reactive blue 171 dye by ceric ammonium nitrate

“…Analysis of variance (ANOVA) is a collection of statistical models used to analyze the differences between group means and their associated procedures to test the null hypothesis against an alternative hypothesis whose details have been explained in our previous work .…”

“…Ideally a suitable degradation process should be economical as well as fast. The cost for CAN treatment was calculated and compared with ozonation and UV/H 2 O 2 treatments where, RB 171 dye (50 mg/L, 50 mL) was degraded in our previous work . Operating cost of CAN treatment was calculated by considering the cost of CAN reagent as 8550 Rs/kg.…”

“…In order to apply the dye degradation study on practical grounds, it is essential to establish the toxicity levels of a dye and its degradation products. Phytotoxicity studies were performed using Phaseolus mungo (dicotyledon) and Triticum aestivum (monocotyledon), as explained in our previous work .…”

“… have adsorbed the dye on fly ash whereas Khan and Husain decolorized it by using potato ( Solanum tuberosum ) soluble and immobilized polyphenol oxidase. Oxidative degradation pathway by ozonation of this dye has been reported in our earlier work which has been explored using CAN in this study. Keeping in view its widespread use in cotton dyeing and thereby its large discharge in the textile process house wastewater, the dye RB 171 was chosen for this work.…”

Brine Recycling from Industrial Textile Wastewater Treated by Ozone. By-Products Accumulation. Part 1: Multi Recycling Loop

“…Color, COD, TOC or BOD removal Simulated [17,[21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38] Industrial [19,[39][40][41][42][43][44][45][46][47] Kinetic study Simulated [25][26][27]30,31,33,35,37,[48][49][50][51][52][53][54][55][56][57][58][59][60][61][62] Products, degradation mechanism Simulated…”