Comparison of Fenton Method and Microwave Synergistic Fenton Method in Radioactive TBP/OK Waste Liquid Treatment

Radioactive TBP/kerosene(OK) organic waste liquid is produced in the process of uranium purification and spent fuel retreatment. In order to avoid the safety risks caused by the accumulation of radioactive organic waste liquid over the years, it is urgent to treat it. In this paper, the conventional Fenton oxidation method and microwave synergistic Fenton method were used to treat simulated radioactive TBP/OK waste liquid, and the effects of mass fraction of Fenton’s reagent ρ(${\text{Fe}}^{\text{2+}}$) and ρ(${\text{H}}_{\text{2}}{\text{O}}_{\text{2}}$), initial pH and oxidation time(t) on the removal of chemical oxygen demand(COD) was experimentally investigated. The results of the conventional Fenton oxidation method show that: at the optimal process conditions, ρ(${\text{Fe}}^{\text{2+}}$)=20 mg/L, ρ(${\text{Fe}}^{\text{2+}}$)/ρ(${\text{H}}_{\text{2}}{\text{O}}_{\text{2}}$)=1∶10, initial pH=1.90, t=15 min, the COD removal can reach up to 72.01%; the most important factor is the ratio of ρ(${\text{Fe}}^{\text{2+}}$)/ρ(${\text{H}}_{\text{2}}{\text{O}}_{\text{2}}$), followed by ρ(${\text{Fe}}^{\text{2+}}$), initial pH, and oxidation time. The microwave synergistic Fenton method is superior to the conventional heating Fenton method, and even better than the conventional Fenton oxidation method, when under the same optimal reaction conditions. As for the microwave synergistic Fenton method, the COD removal can be increased to 95.80%. The dosage of Fenton reagent is also reduced from ρ(${\text{Fe}}^{\text{2+}}$)=20 mg/L, ρ(${\text{H}}_{\text{2}}{\text{O}}_{\text{2}}$)=200 mg/L to ρ(${\text{Fe}}^{\text{2+}}$)=10 mg/L, ρ(${\text{H}}_{\text{2}}{\text{O}}_{\text{2}}$)=100 mg/L. It can be seen that the microwave synergistic Fenton method not only further improves the COD removal, but also reduces the dosage of Fenton reagent.