Na_2O/Al_2O_3摩尔比对模拟高放废液硼硅酸盐玻璃固化体结构和性能的影响  

Effects of Na_2O/Al_2O_3 Molar Ratio on the Structure and Performances of Borosilicate Glass Wasteforms for Simulated High-Level Radioactive Liquid Waste

作　　者：廖其龙[1] 蔺海艳[1] 王辅[1] 潘社奇[2] 牟涛[2] 

机构地区：[1]西南科技大学材料科学与工程学院,四川绵阳621010 [2]中国工程物理研究院,四川绵阳621900

出　　处：《核化学与放射化学》2014年第4期235-240,共6页Journal of Nuclear and Radiochemistry

基　　金：国防基础科研计划资助项目(B3120110001);国家自然科学基金资助项目(91126015);西南科技大学重点资助项目(11zx2101)

摘　　要：研究了Na2O/Al2O3摩尔比(n)对模拟高放废液硼硅酸盐玻璃固化体结构和性能的影响。利用红外光谱分析了不同Na2O/Al2O3摩尔比时硼硅酸盐玻璃固化体的结构变化,并用溶解速率法(DR)和全谱直读等离子发射光谱(ICP-OES)表征了所制备出固化体的化学稳定性。结果表明:在研究组分范围内,当n<1.0时,硼硅酸盐玻璃固化体结构中Al以[AlO4]四面体的形式存在,但[BO3]三角体的量较大;随着Na2O/Al2O3摩尔比的增加(n=1.0),固化体结构中[BO3]三角体向[BO4]四面体转变,Al仍以[AlO4]四面体的形式存在,固化体结构稳定性增加;Na2O/Al2O3摩尔比继续增加(n=1.5或2.0),固化体成分中由于Al含量已很少而使[AlO4]含量过少,对固化体结构网络致密性的影响起主要作用,且此时成分中存在过多的碱金属离子在结构中起断网作用,玻璃固化体网络结构变疏松。在Na2O/Al2O3摩尔比为1.0时,玻璃固化体有相对较佳的结构稳定性和化学稳定性,浸泡56d后的失重速率为10-9 g/(cm2·min)数量级,且浸出液中各浸出离子的平均浓度最低。The effect of NazO/Al2O3 molar ratios（n） on the structure and properties of boro- silicate glass wasteforms was investigated. The structural changes of borosilicate glass wasteforms with different Na20/A12O3 molar ratios were characterized by Fourier transform infrared spectroscopy（FTIR） analysis, and the chemical durability was measured by using dissolution rate（DR） method and direct reading plasma emission spectroscopy（ICP-OES）. The results show that： within the studied composition scope, when n〈1. 0, A1 exists as [AlO4] tetrahedron in borosilicate glass wasteforms, but there are large number of triangu- lar [BO3] existed in its structure; with the increase of Na2O/Al2O3 molar ratio （n=1.0）, the structure stability of the wasteform increase for the transformations of triangular [BO3] to [BO4] tetrahedron; however, when the molar ratio of Na2O/Al2O3 continually increase （n=1. 5 or 2.0）, the structure of glass wasteforms become poor, because A1 content is very few result in too much decreased [AlO4 ] content, which plays an important role in influence of the network density at this condition, and excessive alkali metal ions have the effect of broking network in the structure. When Na2O/Al2O3 mole ratio is 1.0, the good structural and chemical stability are obtained. The value of DR for the glass wasteform is 10 9 g/ （cm2 · min） order of magnitude after 56 d at 90℃, and the concentration of ions in leached water is the lowest.

关 键 词：硼硅酸盐玻璃 固化体 AL2O3 化学稳定性 

分 类 号：TQ171[化学工程—玻璃工业]