Synthesis, Characterization and Photocatalyticdegradation of Acid Dyes Using Hydrogen Peroxide (H2o2) As A Catalyst.

Abstract

This study reports the synthesis, characterization, and photocatalytic degradation of a 
novel azo dye derived from 6-amino-2-(5-chloro-1,3-dioxoisoindolin-2-yl)-1H
benzo[de]isoquinoline-1,3(2H)-dione as a key intermediate. The intermediate was 
diazotized and subsequently coupled with H-acid (4-amino-5-hydroxynaphthalene-2,7
disulfonic acid) to yield the target dye. Structural and physicochemical characterization 
of the synthesized dye was carried out using melting point determination, UV–Visible 
spectroscopy, Fourier Transform Infrared (FT-IR) spectroscopy, and proton nuclear 
magnetic resonance (^1H-NMR) spectroscopy. The dye was further evaluated for 
photocatalytic degradation using a UV/H₂O₂ advanced oxidation system in a photoreactor. 
The degradation process was systematically investigated by varying four operational 
parameters: solution pH, initial dye concentration, catalyst (H₂O₂) loading, and irradiation 
time. Experimental design, optimization, and statistical analysis of main and interaction 
effects were performed using Minitab 17 software. Optimization results indicated that 
maximum degradation efficiency of 72.1417% (desirability = 0.73063) was achieved under 
the following conditions: dye concentration of 10 mg/L, H₂O₂ loading of 2 mL, irradiation 
time of 90 minutes, and acidic medium at pH 3.0. The findings demonstrate that the 
UV/H₂O₂ photocatalytic system is effective for the degradation of the synthesized acid 
dye. Consequently, this approach shows significant potential for application in the 
treatment of tannery and textile wastewater containing recalcitrant dye pollutants.