CAJ | 학술논문

研究了模拟处置条件下 Pu(Ⅳ)的溶解行为,测定了 Pu(Ⅳ)在北山地下水和去离子水中的溶解度。采用过饱和法,使用低氧手套箱模拟地下无氧环境,利用超过滤实现固液分离,应用低本底液闪谱仪测量液相中钚的放射性活度。结果表明：溶解-沉淀平衡后,无论是在去离子水还是北山地下水中,钚的主要存在价态为+4。Pu(Ⅳ)在北山地下水和去离子水中的溶解度分别为(2.8±0.9)×10-8 mol/L 和(1.6±0.8)×10-9 mol/L。通过计算确定了 Pu(Ⅳ)在去离子水和北山地下水中的溶解度控制固相为 Pu(OH)4(am)。在去离子水体系中,Pu(Ⅳ)的主要存在形态为 Pu(OH)4(aq)；北山地下水体系中,Pu(Ⅳ)的主要存在形态为Pu(OH)4(aq)和 Pu(OH)2(CO3)2-2。
연구료모의처치조건하 Pu(Ⅳ)적용해행위,측정료 Pu(Ⅳ)재북산지하수화거리자수중적용해도。채용과포화법,사용저양수투상모의지하무양배경,이용초과려실현고액분리,응용저본저액섬보의측량액상중비적방사성활도。결과표명：용해-침정평형후,무론시재거리자수환시북산지하수중,비적주요존재개태위+4。Pu(Ⅳ)재북산지하수화거리자수중적용해도분별위(2.8±0.9)×10-8 mol/L 화(1.6±0.8)×10-9 mol/L。통과계산학정료 Pu(Ⅳ)재거리자수화북산지하수중적용해도공제고상위 Pu(OH)4(am)。재거리자수체계중,Pu(Ⅳ)적주요존재형태위 Pu(OH)4(aq)；북산지하수체계중,Pu(Ⅳ)적주요존재형태위Pu(OH)4(aq)화 Pu(OH)2(CO3)2-2。
Solubility of Pu (Ⅳ)was determined by oversaturation method under simulated disposal conditions.The underground anaerobic condition was simulated in glove-box.The solid-liquid separation was achieved by ultrafiltration.The plutonium radioactivity was meas-ured by low background liquid scintillation spectrometer.The results show that the domi-nant oxidation state of plutonium either in deionized water or Beishan groundwater is tetrava-lent.The solubility of Pu(Ⅳ)in Beishan groundwater and deionized water is (2.8±0.9)× 10-8 mol/L and (1.6 ±0.8)× 10 -9 mol/L.The specific ion interaction theory was used to calculate the thermodynamics constants under the experimental conditions.Either in deion-ized water or Beishan groundwater,the solubility-controlling solids phase is hydroxide pluto-nium (amorphous).In deionized water,the dominant species is hydroxide plutonium.In Beishan groundwater,the dominant species is hydroxide plutonium and Pu(OH)2 (CO3 )2 -2 .