摘要
以阳江中低放核废物处置库围岩花岗岩为研究对象,通过静态吸附实验探究了阳江花岗岩围岩吸附Sr^(2+)的行为,详细研究了接触时间、初始浓度、反应温度、pH值、阴阳离子对花岗岩吸附行为的影响,并通过表征手段研究了阳江花岗岩的物化组成。结果表明:阳江花岗岩是一种主要由硅氧化物构成的岩石,吸附后其表面变得粗糙。吸附在5 d达到吸附平衡,属于化学吸附行为。吸附和Langmuir等温模型拟合效果更好,Sr^(2+)更多吸附在阳江花岗岩的表面。酸性和碱性环境均会削弱阳江花岗岩对Sr^(2+)的吸附能力,且升高温度和增大初始浓度均有利于吸附。地下水中存在的Ca^(2+)、Mg^(2+)、Fe^(3+)、NO_(3)^(-)均会抑制阳江花岗岩对Sr^(2+)的吸附,CO_(2)-3会和Sr^(2+)生成聚合物而干扰吸附。此研究可以为阳江中低放核废物处置库的安全评估提供一定参考。
Studying the adsorption behavior of Yangjiang granite to Sr^(2+)is very meaningful for the safety assessment of the low-and medium-level nuclear waste repository in Yangjiang.In this study,experimental samples were obtained from the granite rock formations near the low-and medium-level nuclear waste repository in Yangjiang.The static adsorption experiment was performed study the adsorption behavior of Yangjiang surrounding rocks granite on Sr^(2+).And the effect of contact time,initial concentration,reaction temperature,pH,as well as cation and anion on the adsorption behavior of granite was studied in detail.The physical and chemical compositions of Yangjiang granite were investigated by X-ray diffraction spectra(XRD),X-ray fluorescence spectrometer(XRF),scanning electron microscopy-energy dispersive spectroscopy(SEM-EDS),Fourier transform infrared spectra(FTIR)and Zeta potential analyzer.The characterization studies show the granite surface becomes rough after adsorption.The results of static adsorption experiments indicate that adsorption equilibrium time is about 5 days.The Sr^(2+)adsorption decreases with the increase of Sr^(2+)concentration which conforms to the Langmuir isotherm adsorption model and belongs to single-layer adsorption.Under neutral and higher temperature conditions,the adsorption effect is better.The fitting thermodynamic equation suggests that adsorption is a spontaneous endothermic reaction.The ion in groundwater such as Ca^(2+),Mg^(2+),Fe^(3+),NO_(3)^(-) all can inhibit the adsorption of Sr^(2+)by Yangjiang granite,while CO_(3)^(2-) can interfere with adsorption by forming polymers with Sr^(2+).The results of this study can provide a certain reference for the safety evaluation of the low-and medium-level nuclear waste repository in Yangjiang.
作者
蒋巧
王彦惠
成建峰
潘跃龙
洪涛
包晨阳
刘羽
冷阳春
王李涛
庹先国
JIANG Qiao;WANG Yan-hui;CHENG Jian-feng;PAN Yue-long;HONG Tao;BAO Chen-yang;LIU Yu;LENG Yang-chun;WANG Li-tao;TUO Xian-guo(College of Nuclear Technology and Automation Engineering,Chengdu University of Technology,Chengdu 610059,China;China Nuclear Power Engineering Co.,Ltd.,Shenzhen 518000,China;School of National Defense Science and Technology,Southwest University of Science and Technology,Mianyang 621000,China)
出处
《核化学与放射化学》
CAS
CSCD
北大核心
2023年第3期250-258,I0004,共10页
Journal of Nuclear and Radiochemistry
