Photocatalytic degradation of a diazo-dye in artificial seawater matrix: Optimization of UV/H2O2 process on the Ponceau S decolorization by using central composite design

Abstract

The photocatalytic oxidation using the highly reactive hydroxyl radical from UV/H 2 O 2 system is one of the advanced oxidation processes (AOPs) that destroy or even mineralize organic pollutants, which are harmful to the environment. However, certain costs must be controlled by taking into account influencing factors such as the dose of irradiance, oxidant dosage, and the complexity of the background matrix, among others. The objective of this work was to optimize Ponceau S (PS) degradation efficiency by UV/H 2 O 2 process in artificial seawater by using central composite design (CCD). The three selected factors were the hydrogen peroxide concentration, the irradiated volume and the PS dosage. The regression analysis showed good fit of the experimental data to the second-order polynomial model with a correlation coefficient (R 2 ) of 0.9612. The optimal conditions were found to be: [PS] = 50.91 mg/L, [H 2 O 2 ] =2.24 mM, and irradiated volume = 600 mL. Under these conditions, the PS decolorization efficiency was equal to 72.47%.

Theoretical study of Ponceau S oxidation using the electro-Fenton process under optimal operational conditions

“…Advanced oxidation processes (AOPs) are considered as high-efficiency physical-chemical processes due to their thermodynamic viability and capability to degrade or even mineralize a wide range of contaminants via the participation of free radicals, 9,10 mainly HOc hydroxyl radicals. 11,12 The electro-Fenton (EF) process is a potentially effective AOP for treating several kinds of effluents. 1 There are notable advantages of electrochemistry, including energy efficiency, versatility and environmental suitability as the electrons and main-stream reagents are clean.…”

Oxidative degradation of micropollutants by a pilot-scale UV/H₂O₂ process: Translating experimental results into multiphysics simulations

“…Numerous studies have already focused on evaluating the effectiveness of UV/H 2 O 2 process on the (bio)degradation of pollutants such as industrial discharge or pharmaceuticals in laboratory and pilot plant configurations, with varying degrees of success [9][10][11][12]. Researchers have previously explored the traditional kinetics behind the UV/H 2 O 2 system by using key (photo)chemical reaction mechanisms or proposing degradation pathways.…”