Applied Geochemistry最新文献_第5页

Towards a definition of a spatial geochemical compatibility: workflow, validation, and application

IF 3.1 3区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Applied Geochemistry

Pub Date : 2025-01-01 DOI: 10.1016/j.apgeochem.2024.106260

Marino Vetuschi Zuccolini , Simone Pittaluga , Marianna Miola

Decision-making in environmental monitoring and remediation is heavily influenced by technical and regulatory tools. However, these tools often fail to take full account of the spatial heterogeneity of geological matrices. This diffuse behavior results in an ineffective approach to managing local environmental characteristics. To address this issue, stochastic geochemical modelling allows for more informed management of remediation thresholds by quantifying the spatial uncertainty of a regionalized variable. In this context, our research aims to explore the concept of geochemical compatibility of a matrix using a stochastic approach. In particular, the spatial geochemical compatibility (SGC) of stream sediments will be investigated using a tailored processing workflow to ensure a priori data quality control. The proposed workflow formalises a multi-step computational pipeline that includes the definition of computational domains, the implementation of geostatistical techniques and the performance checking of the stochastic model. The application of the pipeline provides a digital stochastic-based representation of the uncertainty about stream sediments of a heterogeneous area for 34 elements.

For each element, 8 layers summarize as many statistical indices as are extracted from the local cumulative probability density functions. The pipeline has been validated by testing it in the heterogeneous mountainous area of the Liguria region (Italy) and a multilayer high-resolution (200 m) geochemical numerical model (GNM-L) has been generated. This model is starting from 2021 publicly distributed and used as a decision support tool for SGC in routine regulatory and monitoring practice. It empowers the community with geochemical knowledge and helps local decision makers to understand and use the concept of environmental uncertainty. Deep control over each computational step and quality control of performance suggests how the pipeline can be generalized in complex areas, from single catchments to entire countries, and for different regionalized variables.

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引用次数: 0

Internal loading of antimony from mining contaminated sediments under oxic conditions

IF 3.1 3区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Applied Geochemistry

Pub Date : 2025-01-01 DOI: 10.1016/j.apgeochem.2024.106272

Kuzey Güneşli , John Chételat , Michael J. Palmer , Katrina Paudyn , Brittany Astles , Heather Jamieson

The environmental fate of antimony (Sb) in aquatic ecosystems has been less studied compared to other metal(loid)s released by mining. This study investigated Sb flux from lake sediments of Yellowknife Bay (Great Slave Lake, Northwest Territories, Canada), which were contaminated by gold mining operations. Sediment Sb fluxes were measured in the field by short term (2–6 day) incubations of intact sediment cores and in the laboratory by incubating bulk sediment over a longer 30-day period. Antimony diffusion from sediment to overlying water was observed in 17 of 28 intact cores (61%), with flux rates ranging from 10 to 279 μg/m²/day. Overlying water and surface sediment remained oxic during the field measurements. Sediment Sb concentration (0.7–47 μg/g) was positively correlated with Sb flux, and the mineralogy of the sediment, characterized in a companion study, likely influenced flux spatial patterns. Other environmental factors, specifically season, temperature, organic matter content, and iron or manganese concentrations of sediment did not explain Sb flux. Porewater Sb concentrations were low (0.2–9.6 μg/L), and porewater depth profiles were not related to solid-phase Sb concentration, suggesting limited post-depositional mobility within sediments. Laboratory incubation of mixed bulk sediments showed higher Sb fluxes of 185–1555 μg/m²/day over the course of a 30-day experiment. Temperature warming from 7 to 22 °C did not enhance the Sb flux. Higher Sb fluxes in the laboratory versus field measurements may have been due to (i) more Sb in the laboratory sediments (∼160 μg/g), and (ii) oxidative dissolution of stibnite and Sb sulfosalt minerals that were previously stable in deeper anoxic sediments but disturbed and exposed to oxygen during laboratory manipulation. This study demonstrated that Sb can diffuse from mining-contaminated sediments into overlying water under oxic conditions, with fluxes influenced by sediment Sb concentrations and mineralogy.

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引用次数: 0

Site-specific structure and energetics of uranyl adsorption at hydrated muscovite (001) surfaces probed by classical molecular dynamics simulations

IF 3.1 3区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Applied Geochemistry

Pub Date : 2025-01-01 DOI: 10.1016/j.apgeochem.2024.106255

Narasimhan Loganathan , Andrey G. Kalinichev

A new series of molecular dynamics (MD) simulations of the Cs⁺ and UO₂²⁺ adsorption on the basal (001) surface of muscovite from relatively low concentration aqueous solutions demonstrates both ions are preferably adsorbed near the centers ditrigonal cavities on this surface. A more realistic random distribution of isomorphic Al/Si substitutions in the muscovite structure allowed us to identify three types of surface adsorption sites somewhat differing in their composition, structure, and local charge distribution. UO₂²⁺ ions are preferably adsorbed as outer-sphere surface complexes with one H₂O molecule in their hydration shell acting as a bridge to the surface. Adsorption free energies for UO₂²⁺ ions at each of the three different adsorption sites were obtained via potential of mean force (PMF) calculations. These adsorption free energy profiles as a function of distance along the direction normal to the surface indicate that UO₂²⁺ ions at two the adsorption sites exhibit only stable OS surface complexes with energy minimum around −26 kJ/mol. At the same time at the third adsorption site, that was not observed and studied in earlier simulations, an inner-sphere surface complex is identified with an energy minimum almost twice as deep as the outer-sphere complexes at the two other adsorption sites. Significant agreement of the present results with available experimental data and results of other MD simulations is also demonstrated, while the sources of observed disagreements and inconsistencies are identified and discussed in detail.

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引用次数: 0

Distribution and evaporation characteristics of Rb and Cs in complex salt brine systems

IF 3.1 3区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Applied Geochemistry

Pub Date : 2025-01-01 DOI: 10.1016/j.apgeochem.2024.106216

Shouyan Huang , Yanfang Ma , Xin Liu , Xiuzhen Ma , Zhenhai Fu

The brine in salt lakes is rich in resources, including not only K, Mg, and B, but also valuable trace elements. During the enrichment and extraction of trace elements (Rb, Cs) from carbonate type salt lake brines, the process is significantly influenced by the presence of other coexisting ions such as Li⁺, K⁺, and Mg²⁺.The physical and chemical properties of K⁺ are extremely similar to those of Rb⁺ and Cs⁺, and its impact on the extraction of Rb⁺ and Cs⁺ is particularly significant. When K⁺, Rb⁺, and Cs⁺ coexist, they can form solid solutions such as [(K, Rb)₂SO₄], [(K, Cs)₂SO₄], and [(Rb, Cs)₂SO₄]. The formation of these solid solutions can lead to severe losses of Rb and Cs during the evaporation process of the brine, resulting in low yield. In response to the aforementioned issues regarding the evaporation process of Rb and Cs, this paper uses the aqueous-salt system phase diagram as a guide and combines experimental research with simulation calculations to study the enrichment patterns of trace elements Rb and Cs in the Na⁺, K⁺//Cl⁻, CO₃²⁻, SO₄^2--H₂O aqueous-salt system, as well as the migration mechanism of Rb and Cs.

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引用次数: 0

Recent depositional history of noble and critical elements in sediments from a wastewater-impacted bay (Vidy Bay, Lake Geneva, Switzerland) 瑞士日内瓦湖维迪湾受污水影响的海湾沉积物中贵重元素和关键元素的近期沉积史

IF 3.1 3区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Applied Geochemistry

Pub Date : 2024-11-27 DOI: 10.1016/j.apgeochem.2024.106240

Jean-Luc Loizeau , Guillaume Jiranek , Antonio Cobelo-García , Montserrat Filella

Opposing trends in environmental pollution have been observed in recent years, with a growing awareness of the need to reduce emissions to the environment being accompanied by a concomitant increase in the use of polluting substances, which can potentially end up in the environment and harm humans and ecosystems. In order to assess the temporal evolution of loadings of seldom monitored trace elements, including noble metals and some technology critical elements, we analyzed a sediment core taken from the Bay of Vidy (Lake Geneva), impacted by the effluent of an urban wastewater treatment plant (WWTP). The temporal profiles of the chemical elements show essentially two patterns linked to the implementation of the WWTP, with some elements increasing sharply (e.g. Au, In, Ba, Sb, Sn, platinum group elements), while others (e.g. Ga, Ge, rare earth elements) show decreasing concentrations due to dilution by additional effluent particle loads. The origin of the elements showing a marked increase is attributed to local sources (photographic industry and municipal incinerator). There is (still?) no evidence in the sedimentary record of concentration increases linked to the growing use of technologically critical elements by industry.

近年来，在环境污染方面出现了相反的趋势，人们日益意识到需要减少对环境的排放，同时污染物质的使用也随之增加，这些物质最终可能进入环境并危害人类和生态系统。为了评估很少监测到的微量元素（包括贵金属和一些技术关键元素）的载荷的时间演变，我们分析了来自Vidy湾（日内瓦湖）的沉积物岩心，受到城市污水处理厂（WWTP）流出物的影响。化学元素的时间分布基本上显示了与实施污水处理计划有关的两种模式，其中一些元素急剧增加（例如Au、In、Ba、Sb、Sn、铂族元素），而另一些元素（例如Ga、Ge、稀土元素）由于被额外的流出颗粒负荷稀释而浓度下降。显示明显增加的元素的来源归因于当地来源（照相工业和市政焚化炉）。在沉积记录中（仍然）没有证据表明浓度的增加与工业日益使用技术关键元素有关。

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引用次数: 0

Rare earth element (REE) speciation in municipal solid waste incineration ash 城市生活垃圾焚烧灰中稀土元素（REE）形态分析

IF 3.1 3区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Applied Geochemistry

Pub Date : 2024-11-27 DOI: 10.1016/j.apgeochem.2024.106239

Yinghao Wen , Lei Hu , Pan Liu , Qian Wang , Estefania Garcia , Weiyao Yan , Yuanzhi Tang

A robust and sustainable supply of rare earth elements (REE) is critically needed for clean-energy technologies, which has stimulated substantial interests in REE recovery from waste streams. Municipal solid waste incineration ash (MSWIA) was recently recognized as a potentially important REE resource, yet REE speciation in MSWIA remains poorly understood. This study employed synchrotron X-ray spectroscopy and microscopy techniques to elucidate the speciation of representative REE (Y, Ce, and Nd) in different MSWIA samples. Linear combination fitting of bulk X-ray absorption near edge structure (XANES) data indicated that Y-bearing Al/Fe oxides and phosphates are the primary Y-hosting phases. Micro-XANES of individual Y-containing particles identified by micro X-ray fluorescence (μXRF) mapping revealed notably different Y speciation at micro-scale from the bulk, consistent with the highly heterogeneous nature of MSWIA samples. The main REE-bearing phases in different size-fractionated MSWIA are similar: Y and Nd as oxides and xenotime/monazite, and Ce as apatite and monazite. Our results provide important insights for designing pre-screening processes (e.g., density separation) and optimizing extraction methods (e.g., pH, use of ligands) for cost-effective REE recovery from MSWIA.

清洁能源技术迫切需要强劲和可持续的稀土元素供应，这激发了人们对从废物流中回收稀土元素的巨大兴趣。城市生活垃圾焚烧灰（MSWIA）最近被认为是一种潜在的重要稀土资源，但MSWIA中的稀土元素形态仍然知之甚少。本研究采用同步x射线光谱学和显微技术来阐明不同MSWIA样品中具有代表性的稀土元素（Y， Ce和Nd）的形态。体x射线吸收近边结构（XANES）数据的线性组合拟合表明，含y的Al/Fe氧化物和磷酸盐是主要的含y相。通过微x射线荧光（μXRF）定位鉴定的单个含Y颗粒的微xanes显示，在微观尺度上，Y的形态与体积明显不同，这与MSWIA样品的高度异质性一致。不同粒度分选MSWIA的主要含稀土相相似：Y和Nd为氧化物和xenotime/monazite， Ce为磷灰石和monazite。我们的研究结果为设计预筛选过程（如密度分离）和优化提取方法（如pH值，配体的使用）提供了重要的见解，从而具有成本效益地从MSWIA中回收稀土元素。

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引用次数: 0

Assessment of landscape impact on snow chemical composition in terms of mineral geochemical exploration 从矿物地球化学勘查角度评价景观对积雪化学成分的影响

IF 3.1 3区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Applied Geochemistry

Pub Date : 2024-11-26 DOI: 10.1016/j.apgeochem.2024.106238

Igor S. Sobolev , Roman Yu Gavrilov , Egor G. Yazikov , Mikhail P. Tentyukov , Irina A. Matveenko , Albina А. Khvashchtvskaya , Nadezhda P. Soboleva , Viktor S. Buchelnikov

In areas with cold climate seasonal snowpack is an attractive sampling material for geochemical exploration of deep mineral accumulations. However, previous studies on assessment of exploration efficiency of snow cover have paid little attention to snow composition variability conditioned by local landscape structure.

The layered sampling of snow sections was performed in different landscape settings of the local area. The research area is characterized by the absence of ore mineralization zones and low anthropogenic load. The physical-chemical parameters and concentration of wide range of elements were identified in snowmelt. Multi-component data was integrated by means of factor principal component analysis. Besides, additive and differential geochemical indexes were used. The classification snow models were developed using hierarchical cluster analysis. The variance of chemical elements distribution and factor models of geochemical pattern were compared before and after reduction of background fluctuation. In terms of variation coefficient values of chemical elements the area has background parameters of chemical inhomogeneity. In total variance a lateral component prevails over a vertical one. The highest concentrations of chemical elements were found in snow section of forest landscape. It is necessary to take into account the fact of geochemical background fluctuation when interpreting the data of metal assay snow survey.

After the reduction of lateral geochemical background fluctuation, the factor model has better classified the chemical elements in terms of their connection with soluble and insoluble occurrence forms. The values of differential index of liquid and solid phases have a similar satisfactory vertical variability in different landscapes. The analysis of chemical elements concentration reveals snow horizons that were or are affected by thaw and percolating water. The snow bottom layer, which is sampled at geochemical exploration, is not strong influenced by elution.

在寒冷气候地区，季节性积雪是深部矿床化探中极具吸引力的采样材料。然而，以往的积雪勘探效率评价研究很少关注局部景观结构条件下的积雪组成变异性。在当地不同的景观设置下，对雪段进行分层采样。研究区无矿化带，人为负荷低。确定了融雪中多种元素的理化参数和浓度。采用因子主成分分析方法对多成分数据进行整合。此外，还采用了加性和差异性地球化学指标。采用层次聚类分析方法建立分类雪模型。对比了背景波动减小前后化学元素分布和地球化学格局因子模型的方差。在化学元素变异系数值方面，该区域具有化学不均匀性的背景参数。在总方差中，横向分量大于垂直分量。森林景观中化学元素浓度最高的是雪区。在解释金属测雪资料时，有必要考虑地球化学背景波动的事实。在减少横向地球化学背景波动后，因子模型对化学元素与可溶性和不溶性赋存形式的联系进行了较好的分类。在不同的景观条件下，液相和固相的差指数具有相似的、令人满意的垂直变异性。对化学元素浓度的分析揭示了曾经或正在受到解冻和渗水影响的雪层。化探取样的雪底层受淋洗液的影响不大。

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引用次数: 0

Radionuclide release from spent nuclear fuel in sealed glass ampoules 密封玻璃安瓿中乏核燃料释放的放射性核素

IF 3.1 3区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Applied Geochemistry

Pub Date : 2024-11-25 DOI: 10.1016/j.apgeochem.2024.106234

Lena Z Evins , Charlotta Askeljung , Alexandre Barreiro Fidalgo , Anders Puranen , Olivia Roth , Kastriot Spahiu

Radiation from spent nuclear fuel affects the redox chemistry of water in the proximity of the fuel surface. The overall effect of the radiolysis is oxidizing so that U(IV) in the spent nuclear fuel is oxidized to U(VI). The dissolution of U(VI) is relatively fast, especially when the water contains bicarbonate. Based on this, radiolytic oxidation is considered the main driving force for spent fuel dissolution and radionuclide release in a spent fuel repository environment, and many studies over the years have aimed to further our understanding of this process and how it is influenced by available redox active components in open and closed systems. Here, data from sealed glass ampoules in which spent fuel is leached for one and five years, are compared with published data from a previous similar experiment. With regards to evolution of radiolytic gases, the results are comparable to the results from the previous experiments: a steady state with regards to oxygen and hydrogen composition is observed. An unexpected observation is that some ampoules with old, pre-oxidized fragments produced less radiolytic gases. These older fragments release a larger fraction of the radionuclide inventory of the samples, yielding concentrations that are on the same level as previously published data. The data from the old fragments presented here are affected by the pre-oxidation and prolonged washing procedure, which confounds the interpretation of those data. New, recently prepared fragments yield data that are easier to interpret. The radionuclide concentrations in the ampoules with new fragments are much lower; uranium concentrations of ca 5E-6 M after one year, and ca 3E-5 M after five years. Using the calculated radionuclide inventory in the fuel samples, an apparent radionuclide release rate in these initially anoxic systems, based on U release, is ca 3E-5 per year.

乏核燃料的辐射影响燃料表面附近水的氧化还原化学反应。放射性分解的总体效果是氧化，因此乏核燃料中的铀（IV）被氧化为铀（VI）。U（VI）的溶解比较快，特别是当水中含有碳酸氢盐时。基于此，放射性分解氧化被认为是乏燃料储存库环境中乏燃料溶解和放射性核素释放的主要驱动力，多年来的许多研究旨在进一步了解这一过程，以及开放和封闭系统中可用的氧化还原活性组分如何影响这一过程。在这里，从密封的玻璃安瓿中提取的数据，将乏燃料在其中浸出1年和5年，与之前发表的类似实验的数据进行比较。关于辐射分解气体的演化，结果与以前的实验结果相当：观察到氧和氢组成的稳定状态。一个意想不到的观察结果是，一些装有旧的、预氧化碎片的安瓿产生的放射性溶解气体较少。这些较老的碎片释放出的放射性核素在样本中所占比例较大，产生的浓度与以前公布的数据处于同一水平。这里展示的旧碎片的数据受到预氧化和长时间洗涤程序的影响，这混淆了这些数据的解释。新的，最近准备的片段产生的数据更容易解释。有新碎片的安瓿瓶中的放射性核素浓度要低得多；一年后铀浓度为5E-6 M，五年后为3E-5 M。利用计算出的燃料样品中的放射性核素库存，根据铀释放量，这些初始缺氧系统中的放射性核素表观释放率约为每年3E-5。

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引用次数: 0

Geochemical constraints on weathering and provenance of stream sediments from Bat Xat, northwestern Vietnam 越南西北部 Bat Xat 溪流沉积物风化和成因的地球化学制约因素

IF 3.1 3区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Applied Geochemistry

Pub Date : 2024-11-22 DOI: 10.1016/j.apgeochem.2024.106235

Anh Tuan Tran , Dung Chi Nguyen , Dung Thi Pham , Tha Van Hoang , Dang Thanh Pham , Qua Xuan Nguyen , Ha Van Vu , Tuan Minh Dang , Tuan Dang Tran , Tai Trong Nguyen , Tra Thu Thi Doan , Thang Sy Cu , Quan Tran Dang , Cong Quoc Tran , Lien Phuong Thi Pham

The stream sediment samples collected from the Bat Xat district in Vietnam have been studied to establish their geochemical characteristics, provenance, weathering intensity, and climate. This comprehensive investigation included major, trace, and rare earth elements (REEs). The sediments were classified as greywacke, lithicarenite, and arkose, denoting compositionally immature deposits. The sediments exhibited moderate chemical weathering in the source domain, with a CIA average value of 67.01, PIA of 73.58, and ICV of 1.05. This suggests a depositional environment influenced by humid climatic conditions attributed to the attenuation of the Indian summer monsoon. The trace element and REE geochemistry of the Bat Xat sediments symbolize their characteristic signatures, with REE patterns mirroring those of their origins. The initial source materials are primarily associated with felsic rocks, with a smaller contribution from sedimentary and metamorphosed sedimentary rocks in the study area. Geochemical characteristics are large fluctuations in Eu/Eu∗ values and high (Gd/Yb)_N ratios. We assume that Bat Xat sediments originated from the exhumated Archean crystalline basement or mixed rocks of the Archean component.

对从越南 Bat Xat 地区采集的溪流沉积物样本进行了研究，以确定其地球化学特征、出处、风化强度和气候。这项综合调查包括主要元素、痕量元素和稀土元素（REEs）。沉积物被划分为灰岩、碎屑岩和霰砂岩，表示成分不成熟的沉积物。沉积物在源域表现出中等程度的化学风化，CIA 平均值为 67.01，PIA 为 73.58，ICV 为 1.05。这表明沉积环境受到印度夏季季风衰减造成的潮湿气候条件的影响。Bat Xat 沉积物的痕量元素和稀土元素地球化学特征象征着它们的特征，稀土元素模式反映了它们的起源。最初的来源物质主要与长英岩有关，研究区域内的沉积岩和变质沉积岩对其影响较小。地球化学特征是 Eu/Eu∗ 值波动较大，(Gd/Yb)N 比值较高。我们推测，Bat Xat沉积物起源于被剥蚀的阿尔川结晶基底或阿尔川成分的混合岩石。

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引用次数: 0

Effect of cellulose degradation products on 63Ni sorption on Portland cement 纤维素降解产物对硅酸盐水泥吸附63Ni的影响

IF 3.1 3区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Applied Geochemistry

Pub Date : 2024-11-22 DOI: 10.1016/j.apgeochem.2024.106237

Delphine Durce, Lian Wang, Nele Bleyen, Marc Van Gompel

Concepts of nuclear waste repositories make use of large quantities of cementitious materials, especially near surface disposal facilities in which cement, mortar, and concrete are used both as structural materials and waste immobilization matrices. The retardation of radionuclides by the cementitious barriers of these repositories is crucial for the safe long-term management of the waste. Yet both the degradation of the cementitious materials and the presence of complexing ligands originating from the waste can affect the sorption of radionuclides. Cellulosic materials present in nuclear waste degrade under irradiation and under the alkaline conditions generated by the cementitious materials and they release organic compounds. Within the cellulose degradation products, α-isosacharinic acid (α-ISA) is generally assumed to be the strongest radionuclide complexant and to have the most impact on radionuclide sorption, though the presence of other ligands in the mixture could also have an effect. In this work, the sorption of ⁶³Ni was assessed on fresh and state III hardened cement paste (HCP). The effect of α-ISA on the ⁶³Ni sorption at these two degradation states was investigated and compared to the effect of a complete mixture of cellulose degradation products generated by irradiation and alkaline degradation of cellulosic tissues. A higher sorption of ⁶³Ni was observed on state III HCP (R_d = (8.6 ± 3.3) × 10³ L/kg) than on fresh HCP (R_d = (1.0 ± 0.3) × 10³ L/kg), and, in both cases, the sorption was higher than previously observed on pure C–S–H (calcium silicate hydrate) suggesting the involvement of other mechanisms than the sole surface complexation on C–S–H. The effect of α-ISA on the sorption of ⁶³Ni depended on the cement degradation state, ranging from no effect on fresh cement to a maximal sorption reduction factor of 8 ± 3 on degraded cement for 10⁻² M α-ISA. The effect of the mixture of degradation products from cellulosic tissues on the sorption of ⁶³Ni was found to be considerably higher on both fresh and degraded HCP, with a sorption reduction factor of 582 ± 972 and 718 ± 327 for the fresh and degraded cement, respectively, for a corresponding α-ISA concentration of 10⁻² M.

核废料储存库的概念利用了大量胶凝材料，特别是近地面处置设施，其中水泥、砂浆和混凝土既用作结构材料，又用作废物固定基质。这些储存库的胶凝屏障对放射性核素的阻滞对废物的长期安全管理至关重要。然而，胶凝材料的降解和源自废物的络合配体的存在都会影响放射性核素的吸收。核废料中的纤维素材料在辐照和胶凝材料产生的碱性条件下降解，并释放出有机化合物。在纤维素降解产物中，α-异糖精酸（α-ISA）通常被认为是最强的放射性核素络合剂，对放射性核素吸附的影响最大，尽管混合物中其他配体的存在也可能有影响。在这项工作中，评估了新鲜和状态III硬化水泥浆（HCP）对63Ni的吸附。研究了α-ISA在这两种降解状态下对63Ni吸附的影响，并与纤维素组织经辐照和碱性降解产生的纤维素降解产物完全混合的效果进行了比较。在III态HCP （Rd =（8.6±3.3）× 103 L/kg）上观察到63Ni的吸附量高于新鲜HCP (Rd =（1.0±0.3）× 103 L/kg)，并且在这两种情况下，吸附量都高于之前在纯C-S-H（水合硅酸钙）上观察到的吸附量，这表明除了C-S-H的表面络合作用外，还涉及其他机制。α-ISA对63Ni吸附的影响取决于水泥的降解状态，α-ISA在10−2 M时对新鲜水泥无影响，对降解水泥的最大吸附还原因子为8±3。结果表明，当α-ISA浓度为10−2 M时，新鲜水泥和降解水泥对63Ni的吸附还原系数分别为582±972和718±327。

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引用次数: 0