Al2O3对独居石玻璃陶瓷固化体的影响

摘要

本文研究了Al2O3掺量对独居石玻璃陶瓷固化体结构和化学稳定性的影响。用傅里叶变换红外光谱（FTIR）和X射线衍射（XRD）方法表征样品结构，用溶解速率法和全谱直读等离子体发射光谱（ICP-OES）分别测定样品在浸出液中浸泡后的失重速率及各元素的浸出浓度，以研究固化体的化学稳定性。研究结果表明：当Al2O3掺量为4％（摩尔分数）时，在980℃下保温3h得到的独居石玻璃陶瓷固化体具有较高的化学稳定性，浸泡14d时其质量浸出率最低，约为8.1ng/（cm2·min），其中Ce、La元素在浸出液中均未检出；固化体的主晶相为独居石，结构中含有大量稳定的正磷酸基团[PO4]3-和少量的焦磷酸基团[P2O7]4-，不存在偏磷酸基团[PO3]-。%The effects of monazite glass-ceramic wasteforms containing different Al2O3 contents on their structures and properties were investigated .The structure of the glass-ceramic wasteforms was analyzed by Fourier transform infrared (FTIR) and X-radiation diffraction (XRD ) . The chemical stability of monazite glass-ceramic wasteforms was measured by dissolution rate and inductively coupled plasma optical emission spectrome-try (ICP-OES) method .The results show that the chemical stability of monazite glass-ceramic wasteforms with 4% (mole fraction) Al2O3 and made at 980 ℃ for 3 h is opti-mal .T he 14 d leaching rate of monazite glass-ceramic wasteforms is about 8.1 ng/(cm2 · min) ,which is the lowest in all the samples .The main crystalline phase of the as-prepared glass-ceramic wasteforms is monazite .There are a large number of [PO4 ]3 -groups ,a small number of [P2O7 ]4 - groups ,and no [PO3 ]- groups in the wasteforms .