Degradation Of Phenol Wastewater By The Iron-doped TiO₂/H₂O₂ System

Phenol is one of the toxic persistent organic pollutants. The phenol wastewater is wide variety of sources and great harm. So, it is a serious problem that how to remove phenol in the wastewater effectively. The photocatalytic oxidation is provided with some adventages in the degradation of phenol, such as mild reaction conditions, ervironment-friendly, completely degradable, and so on. In this paper, TiO₂ was modified with Fe³⁺ (Fe-TiO₂) to improve the photocatalytic activity.The Fe-TiO₂/H₂O₂ synergistic photocatalytic oxidation degradation of phenol has been investigated. The main studies are as follows:(1)The Fe-TiO₂ composite catalysts were prepared by the sol-gel method using tetrabutyl titanate and Fe(NO₃)₃·9H₂O as materials. Fe-TiO₂ was characterized by XRD, DRS, FTIR, SEM-EDAX, respectively. The dependences of photo-catalysts'crystal styles, phase composition and their photocatalytic degration of phenol on the calcination temperature and dosage of Fe³⁺ were investigated. Results showed that, the catalysts doped with 0.1 wt% Fe(NO₃)3·9H₂O, calcined at 550℃for 2h show exllent properties.(2) The impact factors on the removal rate of phenol have been investigated. The results showed that, the removal rate of phenol (100mg/L) under 20W UV light is about 94.4% with 1g/L dosage of the catalyst at room temperature for 3h.(3) The effects of H₂O₂ additional oxidant on Fe-TiO₂ was investigated. The UV lamp(UV 253.7nm), black light(UV 365nm), incandescent (L450 700nm) were used to study the influence of light source on the removal rate of phenol. Results showed that, the degradation efficiency of phenol by Fe-TiO₂/H₂O₂ increases as the light source wavelength increases . In the Fe-TiO₂/H₂O₂/solar system, the optimal dosage of H₂O₂ is about 1ml/L. The photocatalytic oxidation efficiency changed with light intensity, temperature and other environmental factors in the different seasons and different times within 1 day also has been studied, respectively. This can be helpful to the practical application.