α-安息香肟沉淀法分离低浓铀裂变产物中的钼

Separation of Fission Molybdenum from Low Enriched Uranium Products by Precipitation withα-Benzoin Oxime

为研究α安息香肟（α-BO）沉淀法从低浓铀裂变产物中提取裂变^99Mo工艺,考察了 α-BO沉淀法提 取^99Mo的条件,包括温度、HNO3浓度、α-BO 与Mo摩尔比、辐照剂量、 U浓度对（α-80沉淀- Mo的影响, 探索了MoO2 （a-BO）2 沉淀的再溶解条件,测定了α-BO淀法对^131 I、 Sr、 Zr、 RU、 CS、 Ce、 U 等杂质元素的 去污系数,以及Mo回收率.结果表明,在室温下,当 HNO3 浓度为1 mol/L,α-BO Mo摩尔比大于2 时,在无水乙醇和0.4 mol/L NaOH两种 α-BO解体系下, Mo回收率均大于95%.保持辐照剂量率 为 5 000 Gy/h,α-BO淀法提取Mo的回收率随α-BO照剂量的增大而降低.辐照剂量低于8.25 X 105 Gy时,两种 α-BO解体系下, Mo回收率均大于85%.随着U浓度的上升, Mo回收率逐渐下降. MoO2（α-BO2沉淀可在15 min内溶于0. 5 mol/LNaOH溶液中.以上结果表明,采用 α-BO淀法分 离靶件溶解模拟液时,对 Sr、 Zr、 RU、 CS、 Ce、 I、 U 等杂质元素有较好的去污效果.研究结果可为低浓铀 生产裂变99 Mo提供参考.

To separate molybdenum-99 from fission products of low enriched uranium （LEU） by precipitation with a-benzoin oxime （a-BO）, influences of temperature, con-centration of nitrate, molar ratio of a-BO to Mo, radiation dose and uranium concentra-tion on precipitating molybdenum with crBO had been evaluated. Re-dissolution of Mo02（a-BO）2 was performed. The decontamination factors of impurity elements inclu-ding strontium zirconium、 ruthenium、 cesium、 cerium、 iodine-131 and uranium had been determined. The recovery yield of Mo for the separation procedure was calculated.It showed that, at the room temperature, with 1 mol/L of nitric acid concentration ,higher than 2 of molar ratio of a-BO to Mo, when a-BO was dissolved in anhydrous eth-anol or 0. 4 mol/L sodium hydroxide solution, higher than 95% of Mo recovery yield could be obtained. Under the radiation dose rate of 5 000 Gy/h, when the radiation dose increased, Mo recovery yield decreased instead. When the total radiation dose of a-BO was below 8. 25 X 105 Gy, Mo recovery yield was higher than 85%. When uranium con-centration increased, Mo recovery yield decreased. Mo02 （crBO）2 precipitate could be dissolved in sodium hydroxide of 0. 5 mol/L within 15 minutes. Effective decontamina-tion for all major impurity elements including strontium, zirconium, ruthenium, cesium, cerium, iodine and uranium were observed. This study has paved the pay for further research for fission ＂Mo production.