Decoloration and degradation of some textile dyes by gamma irradiation

Radiation induced degradation of dyes—An overview

“…In steady state radiolysis, the sample is normally irradiated for a given time period and the changes in solution property (such as color) is observed by using a spectrophotometer [37]. These experiments can be carried out in a lab setting using glass tubes or glass containers; however for large volumes of solutions, a scanning type of radioactive source is utilized.…”

“…For example, the radiolysis of two different reactive dyes (Reactive Blue 15 and Reactive Black 5) in aqueous solutions at different dose rates has been reported [37]. The change of absorption spectra and the degree of decoloration (percent reduction in optical density) were examined in the presence of air and H 2 O 2 .…”

“…This effect is seen by numerous groups on various dyes [34][35][36][37][38]. At a higher radiation dose, more reactive species are generated in solution, which in turn are available to react with and degrade dye molecules.…”

“…The AOP technique has drawn considerable attention from various quarters of scientific community as it is easy to handle and produces significantly less residuals as compared to the classical approaches. Amongst the many techniques employed in the AOP approach are the UV photolytic technique [9][10][11][12], Fenton process [13][14][15][16][17][18], photo-Fenton process [19][20][21], ozonation process [22], sonolysis [23][24][25], photocatalytic approach [26][27][28][29][30], biodegradation [31][32][33] and the radiation induced degradation of dyes [34][35][36][37]. Furthermore, many workers have coupled the various AOP techniques to obtain significant improvement in their results [38][39][40][41][42][43].…”

Mineralization of reactive Black 5 in aqueous solution by ozone/H2O2 in the presence of a magnetic catalyst

“…The value of the BOD 5 /COD ratio normally indicates the extent of the biological degradability of organics, and that of dyes is usually <0.1 [3]. Therefore, the destruction of biologically recalcitrant organics in textile wastewater must be accomplished via certain methods that enhance the biological degradability of organics, such as advanced oxidation processes (AOPs) [4,5].…”