【摘要】 将超临界流体萃取技术应用于乏燃料后处理中,可简化后处理流程、减少二次废液的产生。本工作进行了含磷酸三丁酯(TBP)的超临界二氧化碳(SC-CO2)络合萃取硝酸钕的实验研究,考察了硝酸钕粒径、TBP流量、系统温度和压力对络合萃取过程的影响。实验结果表明,含TBP的SC-CO2可高效萃取硝酸钕,萃取率达97%以上,增大TBP流量可加快萃取过程,而粒径、温度和压力对萃取速率的影响则较小。由实验结果可推断,该络合萃取过程的动力学受络合反应控制,并用一动力学模型计算出表观反应速率常数。更多还原

【Abstract】 Reprocessing of spent fuel based on supercritical fluid extraction was intensively studied for its promising potential to reduce the secondary liquid waste generated.In this study,complexing extraction of neodymium nitrate hydrate in supercritical carbon dioxide containing tri-n-butyl phosphate(TBP) was investigated,more than 97% of the extraction efficiency was obtained.Effects of different particle sizes,TBP flow rates,temperature and pressure on the extraction efficiency were studied and discussed.It was assumed that the kinetics of the complexing extraction process was controlled by compexing reaction.A kinetics model was proposed to describe the extraction process.更多还原