掺加铬对硼硅酸盐玻璃固化体结构影响

The effect of chromate doped on borosilicate glass's structure

动力堆乏燃料经后处理产生的高放废液中铬的含量比生产堆略高,为了尽可能提高玻璃固化体对有毒有害的重金属铬废物的包容能力,减少该类废物玻璃固化后最终废物体积,实验通过掺加不同量的氧化铬研究其对于硼硅酸盐玻璃(摩尔比n(SiO_2)∶n(B_2O_3)∶n(Na_2O)∶n(Li_2O)=1.03∶0.32∶0.18∶0.18)包容模拟动力堆高放废液的量及玻璃样品结构的影响。六种玻璃样品的X射线衍射和拉曼光谱分析结果显示,废物包容量从10%增至20%(质量分数),硼硅酸盐玻璃样品的结构明显提高(Q1比例降低,Q2等比例提高)。废物包容量增至20%(质量分数)情况下,铬的掺杂量可以达到0.5%(质量分数),玻璃样品没有出现结晶相,其结构比不掺加铬的样品更加稳定。同时,向废物包容量为20%(质量分数)的玻璃样品增加铬的掺杂量增至1%(质量分数),由于铬含量超出硼硅酸盐玻璃包容铬的限值而溢出,形成氧化铬晶相,降低了玻璃样品结构的稳定性和对废物包容的能力。PCT测试结果和SEM分析结果同Raman和XRD分析结果一致。

Since chromium, as one type of the poisonous and dangerous heavy metaU is higher concentrated in the High Level Radioactive Liquid Waste （HL LW ） from Nuclear Power Plants （NPPs） spent fuel than that from yield reactor spent fuel,in order to minimize the final waste form volume9 this paper presented the effect of chromium doped on the waste loading capability and structure stability of borosilicate glass （mole ratio SiO2 ： B2O3 ： Na2O ： Li2 0=1.03 ： 0.32 ： 0.18 ： 0.18）. X-ray reflector diffraction （XRD） and Raman spectroscope analysis results of six borosilicate glass samples show that the borosilicate glass structure was more stable with 20wt% waste loading than that with 10wt% （Q1 factor decreasing and Q2 etc. factor rising）. The sample9 load-ing to 20wt. % waste with 0.5wt% Cr2O3 doped,could still keep homogeneous,and was more stability than others with same waste loading but more Cr2O3 fraction doped. On the other hand,the analysis results also show that Cr2O3 XRD peak appeared in the sample loading 20wt% waste and doping lwt % Cr2O3 , which over-stepped the chromium loading l imit inO borosilicate glass and decreased the structure stability. The results of PCT test and SEM/EDS were agreed with that of Raman spectroscope and XRD.