Acid orange 7

Acid Orange 7 (Orange II; D&C Orange NO. 4) is an azo dye widely used in the textile, food and cosmetic industries. Acid Orange 7 is mainly used as a colorant by combining with fibers and other substances through azo bonds. Acid Orange 7 has a maximum absorption wavelength at 484-485 nm, and the concentration is measured using a UV-visible spectrophotometer. Acid Orange 7 is difficult to degrade and has a certain degree of toxicity. It is often used to study various sewage treatment technologies and photocatalytic degradation reactions, and to evaluate the removal effects of different treatment methods on organic pollutants^[1][2][3]. In Vitro:In the extreme thermophilic mixed culture experiment, the degradation rate of Acid orange 7 (20 mg/L; 80 min) in the system containing H₂O₂ reached 93%, and the reaction conformed to the first-order kinetics. Fe-doped CeO₂ hollow microspheres showed excellent catalytic activity due to their large number of oxygen vacancies, high specific surface area and low band gap^[1].
In the electroperoxide process experiment, Acid orange 7 (500 mg/L; 90 min) achieved 99% decolorization, COD and TOC removal rates were 99% and 90% respectively, and the intermediate product was gradually converted from highly toxic benzoic acid to low-toxic fumaric acid^[2].
In the photocatalytic degradation experiment, acid orange 7 (20 mg/L; 80 min) was degraded by Fe-doped CeO₂ hollow microspheres synthesized by yeast template under visible light, with a degradation rate of 93%, confirming that its degradation follows pseudo-first-order kinetics and depends on the high specific surface area and low band gap characteristics of the material^[3].