【摘要】：90Sr、137Cs是放射性高釋熱核素,在最終地質(zhì)處置中對高放廢液(Highly active liquid waste,HLW)固化體的安全性存在潛在的危害,其有效分離是國際分離科學(xué)與技術(shù)前沿領(lǐng)域尚未攻克的熱點(diǎn)和難點(diǎn)問題之一,以新材料、新技術(shù)和新方法為手段,是從HLW中高效分離回收Cs、Sr的有效途徑。本文基于杯芳冠醚及冠醚衍生物超分子主體,通過制備與表征其高分子基超分子識別材料,研究Cs、Sr及典型共存元素的主-客體識別及吸附行為,為尋找出色的超分子識別材料有效分離Cs、Sr提供理論與實(shí)驗(yàn)依據(jù)。主要研究結(jié)果如下:1.合成 了六種 Calix[4]crown 衍生物:杯[4]雙冠-6(Calix[4]BisCrown-6,BC6)、杯[4]雙冠-5、(Calix[4]BisCrown-5,BC5)、25,27-二(正丙氧基)杯[4]芳烴-26,28-冠-6(nProCalix[4]MonoCrown-6,BnPC6)、25,2,27(異丙氧基)杯[4]芳烴-26,28-冠-6(iProCalix[4]MonoCrown-6,BiPC6)、25,27-二(癸氧基)杯[4]芳烴-26,28-冠-6(NonyloxyCalix[4]MonoCrown-6,NoNC6)和25,227-(十十烷氧基)杯[4]芳烴-26,28-冠-6(DodecyloxyCalix[4]MonoCrown-6,DoDC6);以1H NMR、ESI-MMS、元素分析和SEM等手段,對其組成和結(jié)構(gòu)進(jìn)行了表征。2.以獨(dú)有的真空活化灌注技術(shù),將冠醚衍生物如二環(huán)己基-18-冠-6(DCH18C6,DC)和 4'4"(5")-二叔丁基二環(huán)己基-18-冠-6(DtBuCH18C6,DT)和上述合成的杯芳冠醚同時(shí)導(dǎo)入并固定化在多孔高分子載體XAD-7上,制備了 7種新型三元高分子基超分子識別材料(Calix[4]Crown/Crown-ether/XAD-7);以SEM、N2吸附-脫附等溫曲線、XRD和TG-DSC等手段表征了材料結(jié)構(gòu)和組成,考察了材料復(fù)合機(jī)理。結(jié)果表明:通過分子間的相互作用力超分子主體能與XAD-7有效復(fù)合,形成含有豐富孔徑的新型介孔材料。3.研究了三元高分子基超分子識別材料對模擬高放廢液中Cs、Sr和Rb等20種典型金屬離子的吸附行為;考察了 HNO3濃度、接觸時(shí)間、溫度及pH等因素變化對功能材料吸附性能的影響。結(jié)果表明:7種材料的吸附行為受介質(zhì)酸度和 pH 影響較大。BnPDTX7、DoDDTX7、BC6DCX7、BnPDCX7、NoNDTX7和BC6DCX7對Cs、Sr、Rb、Ba和K有較為顯著的吸附行為,BC5DTX7對K和Rb有顯著的吸附行為,它們對其余15種被試驗(yàn)金屬離子均表現(xiàn)為弱吸附或基本不吸附。4.研究了三元超分子識別材料的吸附等溫線、吸附動力學(xué)及吸附熱力學(xué)模型,提出并討論了吸附機(jī)理。結(jié)果表明:相對于Freundlich模型,高分子基超分子識別材料的吸附更符合Langmuir模型;符合準(zhǔn)二級動力學(xué)模型;且吸附過程表現(xiàn)為單分子層化學(xué)吸附。
[Abstract]:90Sr ~ (137Cs) is a radionuclide with high release heat. In the final geological disposal, there is a potential hazard to the safety of high level active liquid waste liquid (HLW) solidification. Its effective separation is one of the hot and difficult problems that have not been solved in the frontier field of international separation science and technology. By means of new materials, new technologies and new methods, it is an effective way to efficiently separate and recover CSN Sr from HLW. Based on the supramolecular host of calix aryl crown ether and its derivatives, the host-guest recognition and adsorption behavior of CSN Sr and its typical co-existing elements were studied by preparing and characterizing their polymer based supramolecular recognition materials. It provides theoretical and experimental basis for the effective separation of CSN Sr with excellent supramolecular recognition materials. The main results are as follows: 1. 鍚堟垚 浜嗗叚縐，

本文編號：2130073