Modification of Portland cement matrix with diethyldithiocarbamate for technetium immobilization

IF 3.3 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Progress in Nuclear Energy Pub Date : 2024-10-22 DOI:10.1016/j.pnucene.2024.105508

Elena Abramova, Mikhail Volkov, Anton Novikov, Mikhail Grigoriev, Konstantin German, Alexey Safonov

{"title":"Modification of Portland cement matrix with diethyldithiocarbamate for technetium immobilization","authors":"Elena Abramova, Mikhail Volkov, Anton Novikov, Mikhail Grigoriev, Konstantin German, Alexey Safonov","doi":"10.1016/j.pnucene.2024.105508","DOIUrl":null,"url":null,"abstract":"<div><div>The paper considers the effect of sodium diethyldithiocarbamate (SDDC) addition on the immobilization of technetium in a Portland cement matrix. The leaching process was evaluated in a model solution that simulated the conditions of the future radioactive waste (RW) storage site at the Yeniseisky site. The results demonstrated that the addition of 1.0 wt % SDDC to the cement composite increased the incorporation of immobilized technetium into the cement matrix by 35% in comparison to the blank sample. Furthermore, the retention of technetium in the cement matrix was observed to be enhanced, with a retention of up to 90% observed on the 200th day of the experiment. Resulting materials fulfill the necessary technical characteristics for use as a matrix and engineered safety barrier in the concept of deep RW disposal. The addition of SDDC into cement results in microbial respiratory activity decreasing. In order to evaluate the mechanisms of technetium immobilization, the structure of the technetium compound with diethyldithiocarbamate (DDC) [Tc(C<sub>5</sub>H<sub>10</sub>NS<sub>2</sub>)<sub>4</sub>]TcO<sub>4</sub> is described for the first time. This compound contains a Tc(V) atom which coordinates four diethyldithiocarbamate C<sub>5</sub>H<sub>10</sub>NS<sub>2</sub> moieties through eight sulfur atoms to form a complex cation. The addition of SDDC in cement is presumed to result in a cascade of disproportionation reactions and the formation of stable Tc(IV) compounds, as it was evidenced by XANES spectroscopy.</div></div>","PeriodicalId":20617,"journal":{"name":"Progress in Nuclear Energy","volume":"178 ","pages":"Article 105508"},"PeriodicalIF":3.3000,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Progress in Nuclear Energy","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S014919702400458X","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"NUCLEAR SCIENCE & TECHNOLOGY","Score":null,"Total":0}

引用次数: 0

Abstract

The paper considers the effect of sodium diethyldithiocarbamate (SDDC) addition on the immobilization of technetium in a Portland cement matrix. The leaching process was evaluated in a model solution that simulated the conditions of the future radioactive waste (RW) storage site at the Yeniseisky site. The results demonstrated that the addition of 1.0 wt % SDDC to the cement composite increased the incorporation of immobilized technetium into the cement matrix by 35% in comparison to the blank sample. Furthermore, the retention of technetium in the cement matrix was observed to be enhanced, with a retention of up to 90% observed on the 200th day of the experiment. Resulting materials fulfill the necessary technical characteristics for use as a matrix and engineered safety barrier in the concept of deep RW disposal. The addition of SDDC into cement results in microbial respiratory activity decreasing. In order to evaluate the mechanisms of technetium immobilization, the structure of the technetium compound with diethyldithiocarbamate (DDC) [Tc(C₅H₁₀NS₂)₄]TcO₄ is described for the first time. This compound contains a Tc(V) atom which coordinates four diethyldithiocarbamate C₅H₁₀NS₂ moieties through eight sulfur atoms to form a complex cation. The addition of SDDC in cement is presumed to result in a cascade of disproportionation reactions and the formation of stable Tc(IV) compounds, as it was evidenced by XANES spectroscopy.

Abstract Image

查看原文本刊更多论文

用二乙基二硫代氨基甲酸二乙酯改性硅酸盐水泥基质以固定锝

本文探讨了添加二乙基二硫代氨基甲酸钠（SDDC）对锝在波特兰水泥基质中固定化的影响。在模拟叶尼塞斯基场址未来放射性废物 (RW) 储存地条件的模型解决方案中对沥滤过程进行了评估。结果表明，与空白样品相比，在水泥复合材料中添加 1.0 wt % 的 SDDC 可使固定锝在水泥基质中的结合率提高 35%。此外，还观察到锝在水泥基质中的保留率得到了提高，在实验的第 200 天，锝的保留率高达 90%。所得材料满足了深层 RW 处置概念中用作基质和工程安全屏障的必要技术特征。在水泥中添加 SDDC 后，微生物的呼吸活动减少。为了评估锝的固定机制，首次描述了二乙基二硫代氨基甲酸锝化合物（DDC）[Tc(C5H10NS2)4]TcO4 的结构。该化合物含有一个锝（V）原子，通过八个硫原子与四个二乙基二硫代氨基甲酸盐 C5H10NS2 分子配位，形成一个复合阳离子。正如 XANES 光谱所证明的那样，水泥中加入 SDDC 后，可能会发生一连串的歧化反应，并形成稳定的 Tc(IV) 化合物。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Progress in Nuclear Energy 工程技术-核科学技术

CiteScore

5.30

自引率

14.80%

发文量

331

审稿时长

3.5 months

期刊介绍： Progress in Nuclear Energy is an international review journal covering all aspects of nuclear science and engineering. In keeping with the maturity of nuclear power, articles on safety, siting and environmental problems are encouraged, as are those associated with economics and fuel management. However, basic physics and engineering will remain an important aspect of the editorial policy. Articles published are either of a review nature or present new material in more depth. They are aimed at researchers and technically-oriented managers working in the nuclear energy field. Please note the following: 1) PNE seeks high quality research papers which are medium to long in length. Short research papers should be submitted to the journal Annals in Nuclear Energy. 2) PNE reserves the right to reject papers which are based solely on routine application of computer codes used to produce reactor designs or explain existing reactor phenomena. Such papers, although worthy, are best left as laboratory reports whereas Progress in Nuclear Energy seeks papers of originality, which are archival in nature, in the fields of mathematical and experimental nuclear technology, including fission, fusion (blanket physics, radiation damage), safety, materials aspects, economics, etc. 3) Review papers, which may occasionally be invited, are particularly sought by the journal in these fields.