Document Type : Research Paper

Authors

• Farhad Qaderi ¹
• Amir Hossein Norouzi ²

¹ Professor, Faculty of Civil Engineering, Babol Noshirvani University of Technology,Babol, Iran

² Assistant Professor, Technical and Engineering Faculty, Payame Noor University (PNU), Tehran, Islamic Republic of Iran.

Abstract

In this research, the capability of two improved photocatalytic (immobilized-suspended) and hybrid (Ozonation/Improved photocatalytic) method were studied to treat wastewater containing azo dye of Red 40. Hybrid process had the best efficiency for dye concentration of 50 mg/L with pH of 9 and TiO2 concentration of 40 gr/m3 with light source power of 120 W and ozone injection rate of 20 mg/min. In these conditions, dye and COD were removed completely after 65 minutes and 7 hours, respectively. Based on the kinetic studies, pseudo first order model was applied for dye degradation. According to the results, immobilization of nano materials not only solved their recovery problem, but also improved the efficiency of conventional photocatalytic process. Addition of ozonation to the photocatalytic system for the purpose of having hybrid process was also resulted in an increase of the efficiency to over 30 times and production of safe products. The results have been showed the advantages of hybrid process.

Keywords

• Dye wastewater
• Ozonation process
• Immobilized Photocatalyst process
• Kinetic
• Intermediate products