Synthesis and photocatalytic degradation of an acid dye using factorial design

Abstract

A new acid dye was synthesised from the reaction of 6-amno-2-(5-chloro-1,3-dioxoisoindolin-2yl)-1H-benzo[de]isoquinoline-1,3(2H)-dione with J-acid. The synthesised dye was characterised by melting point, UV-visible absorption, FT-IR and ¹H-NMR spectroscopy. The synthesised dye was stimulated and subjected to photodegradation using hydrogen peroxide (H₂O₂) as photocatalyst in the presence of ultraviolet light in a photo reactor. The rate of degradation of the dye solution was determined on the basis of absorbance measurement. Four factors such as dye concentration, pH of the solution, time of irradiation and catalyst loading were used as the operational parameters for the photo-degradation studies. The Minitab 17 software was used to determine the optimized conditions for the experiment. The main effects and interactions between factors were investigated and results analysed. The results for the optimization parameters in the photocatalytic degradation revealed the following conditions for the percentage degradation: Maximum degradation at 67.9 % with the desirability of 0.96462, dye concentration of 10 mg/L, catalyst loading of 2 mL, with the time of irradiation of 90 minutes at pH of 3.9 for the dye. This showed that (UV/H₂O₂) photocatalytic degradation of acid dyes using factorial design were effective and efficient technology which can be used in treatment of tannery and textile effluents.