芬顿氧化法预处理放射性废离子交换树脂

Pre-Treatment of Radioactive Spent Ion Exchange Resin by Fenton Process

为了对放射性废树脂进行预处理，使用芬顿试剂对其进行了氧化降解预处理实验研究。通过正交试验获得了实验操作的合理条件：当过氧化氢的初始浓度为4．0mol／L、亚铁离子的初始浓度为20mmol／L、反应时间为4h、反应温度为95℃、溶液的初始pH值为2．5时，该法对3种不同的含铀废湿树脂（50g）均有理想的降解效果。反应进行2h后废树脂被完全分解，残液中化学需氧量（COD）的去除率达97％以上，由8．0～10．0g／L降至0．2～0．3g／L，且吸收液中铀含量无明显增加。实验结果表明，芬顿试剂对放射性废离子交换树脂有较好的氧化降解效果。

Fenton reagent oxidation experiments were conducted to test its feasibility in pretreatment of radioactive spent ion exchange resin. The effects of reaction conditions such as the dosage of H2O2 and Fe^2＋ , reaction time（t） and reaction temperature（θ） were studied in term of chemical oxygen demand （COD） removal efficiency. The optimum operating conditions determined by the orthogonal experiments are as follows, co （H2O2） = 4. 0 mol/L, c0（Fe^2＋）：20 mmol/L, 0：95 ℃ and t=4 h at pH：2.5. Under optimum operating conditions, approximately 100% decomposition efficiencies can be achieved for three 50 g uranium-containing wet resin samples. The COD is reduced from 8.0-10.0 g/L in the initial solution to 0.2-0.3 g/L in the residual solution. At the same time, the concentration of uranium in the tail-gas absorption solution don＇t remarkably increase. The study results show that the pre-treatment of industrially generated radioactive spent ion exchange resin by Fenton＇s reagent can entail very effective degradation of the resin.