Degradation Of Polyacrylamide In Wastewater By Heterogeneous Photo-Fenton Reaction

Along with each oil-field successively used polymer to enhance the crude oil recovery, the quantity of wastewater contening polyacrylamide(PAM) was increasing. The water contening polyacrylamide was a class relatively complex, special wastewater, the treatment of which became a serious problem. Heterogeneous photo-Fenton reaction catalysis is one of typical advanced oxidation technique. This technique have the feature of higher efficiency and oxidation ability, can avoid precipitation of sludge contained Fe produced by Homogeneous photo-Fenton reaction catalysis, and have strict request to pH, So it was used in wastewater treating widely. But the application on oil wastewater was scarcely.An heterogeneous iron-containing catalyst carried on porous silica was prepared by the impregnation method. The manufacture process was optimized and the optimal condition of the preparation of high active catalyst was acquired. The structure of catalyst was characterized and the catalytic activity was investigated in heterogeneous photo-Fenton reaction catalysis process. The results show that the active component of Fe is exist as FeOOH and Fe2O3 which was distributed Uniformly on the surface of catalyst. As the FeOOH and Fe2O3 were carried into the porous silica, the specific surface area is bigger slightly, and the Total pore volume and average pore size is decreased. It was found that iron-containing catalyst has high catalytic activity, more than 80% TOC removal of PAM can be achieved in 180 min, the problem of TOC removal lower was overcomed.The heterogeneous photo-Fenton reaction catalysis system was builded which was suitable to the three-phase fluidized-bed reactor to treat PAM in wastewater. The optimum condition of the reactor running was accessed by studying this reaction, which the UV intensity, the volume of catalyst, the H2O2 concentration and the volume of aeration of this system to treating wastewater contained PAM respectively is 4.4×10³Î¼w/cm²(8W UV light ), 0.67g/L, 249.75mg/L, 0.20m³/h. The experimental results also showed that the UV intensity have greater effection to this system, the removal rate of PAM is increasing with the increase of UV intensity. When the UV intensity reached 17.6×10³Î¼w/cm²(32w UV light), the removal rate of PAM can reach 100% that after reaction 60 min.Sysmatical analysis for the influencing factors of heterogeneous photo-Fenton reaction catalysis was made. The result showed that the photochemically degradation apparent rate constant of PAM was proportional to hydrogen peroxide dosage and UV intensity, and linearly increased with the increase of [H₂O₂]₀/[PAM]₀.