Treatment Performance of Photocatalysis/H_2O_2/Metal Membrane Process for Organics Removal

摘要

The objective of this study is to evaluate the performance of photocatalysis/hydrogen peroxide/metal membrane system. Metal membrane for the separation of TiO_2 particles was used in an experiment and nominal pore size is 0.5 μm. Hydrogen peroxide was tested as oxidants. The removal efficiency of COD_(Ce) and color for initial hydrogen peroxide concentration increases rapidly with an increase in the hydrogen peroxide concentration up to 50 mg/L. The removal efficiency of of COD_(Cr) and color for 50 mg/L of initial hydrogen peroxide concentration was about 95 % and 98 %, respectively. However, the addition of hydrogen peroxide over 50 mg/L inhibits the system efficiency. The addition of hydrogen peroxide in UV/TiO_2 system enhanced removal efficiency of COD_(Cr) and color compared to no addition of hydrogen peroxide. This may be ascribed to capture the electrons ejected from TiO_2 and to produce OH radicals. The application of metal membrane in UV/ TiO_2/H_2O_2 system enhanced removal efficiency of COD_(Cr) and color due to the adsorption of metal membrane surface as well as the production of OH radical. In application of metal membrane with nominal pore size 0.5 μm, TiO_2 particles were effectively separated from the treated water by metal membrane rejection. Photocatalytic metal membrane was much smaller resistance than these of humic acid, TiO_2 and humic acid/ TiO_2 due to humic acid degradation of photocatalytic reaction.