Study of Acid red ۱ removal from aqueous solution by Photo-Fenton (UV/Fe۲+/H۲O۲) process

Removing colored contaminants from the wastewater output of various industries (such as textile and paint) is the main concern of environmental protection. Regardless that the presence of such pollutants creates an unpleasant appearance, it also may cause irreversible threats to flora and fauna. For example, accumulation of colored pollution in water resources may disrupt the nutrition of aquatic biota. Acid red ۱ (AR۱), which was chosen as the model compound in the present investigation, is a synthetic red azo dye. Azo dyes are the largest class of aromatic dyes having lots of commercial interest. These dyes are mostly used in textile industries. Several physico-chemical techniques have been developed to remove colored contaminants which, of course, the use of simple and efficient methods is crucial. The literature review showed that advanced oxidation processes (AOPs) are useful methods for the removal of various contaminants, especially colored compounds. The aim of this research was to study the remove of AR۱ dye from aqueous solution by Photo-Fenton (UV/Fe۲+/H۲O۲). Effect of four operational variables viz. initial dye concentration, Fe۲O۳ amount, pH, and time was studied in Photo-Fenton process. Modeling and optimization of process was studied using response surface methodology (RSM). Comparing of the theoretical and experimental results showed that the results are in good agreement with each other, which is supported by analysis of variance (ANOVA). Two and three-dimensional graphs (contours and response surfaces) were used to assess the interaction between operational parameters. The findings demonstratedthat, removal efficiency decreased with increasing of initial dye concentration, while it increased with increasing of Fe۲O۳ and H۲O۲ amounts. It also turned out that, removal efficiency increased with increasing of pH and irradiation time.