Photocatalytic Degradation of Dilute Gas-phase Toluene Using Thin film Hybrid Photocatalyst: Kinetic Study for the Effect of Airflow Velocity and Concentration

摘要

A kind of hybrid photocatalyst composed by mordenite and Degussa P-25 titania with weight ratio of 3:1 was found to have similar photoactivity with pure P25 but using much less photocatalyst. The best loading of this hybrid photocatalyst is 0.49 mg/cm~2 for the cases studied. The effects of airflow velocity and concentration of this kind of hybrid photocatalyst on the photocatalytic oxidation of dilute gas-phase toluene in a glass-plate photoreactor were investigated. Two conclusions were reached from the experiments: (1) The photooxidation of toluene is free of mass transfer above the airflow velocity of 1.33 m/s for the cases studied. (2) Single molecular Langmuir-Hinshelwood (L-H) rate form provides a good correlation to the oxidation rates data in the tested concentration range of toluene.