α-Crystalline polyantimonic acid - an adsorbent for radiostrontium, and a potential primary barrier in waste repositories

Dynamic adsorption of radiostrontium was studied on α-crystalline polyantimonic acid grains from aqueous solutions containing common components of liquid radioactive wastes - salts and chelating agents at moderate concentrations. Effective decontamination of the neutral solutions has been achieved, in the amounts of a few thousand bed volumes, depending on the flow rate through the column. After encapsulation in the matrix of Portland cement, the loaded adsorbent can serve as an effective primary barrier in nuclear waste repositories.

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Nuclear Waste Repositories in Crystalline Rock- an Overview of Flow and Nuclide Transport Mechanisms

MRS Proceedings ◽

10.1557/proc-353-7 ◽

1994 ◽

Vol 353 ◽

Cited By ~ 3

Author(s):

Ivars Neretnieks

Keyword(s):

Nuclear Waste ◽

Field Experiments ◽

Fracture Network ◽

Crystalline Rock ◽

Transport Mechanisms ◽

The Matrix ◽

Nuclide Transport ◽

Waste Repositories ◽

And Diffusion ◽

Diffusion Properties

AbstractNuclides eventually escaping from nuclear waste repositories in crystalline rock will move with the seeping water in the fracture network. Most important nuclides interact physically or chemically with the rock and are expected to be considerably retarded allowing them to decay to insignificant concentrations. Velocity variations may allow some portions of the nuclides to move faster. Matrix diffusion and sorption on the surfaces of the rock are by far the most powerful retardation mechanisms and depend, in addition to the sorption and diffusion properties, directly on the magnitude of the “flow wetted surface”which is the contact surface between the mobile water carrying the nuclides and the fracture surfaces over which the nuclides diffuse into the matrix.A number of field experiments have been performed over the last 15 years to help validate the concepts and models and to obtain data. A number of such experiments are described and discussed in relation to the above issues.

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Absorption of oxygen into solutions of polymers

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19862127 ◽

1986 ◽

Vol 51 (10) ◽

pp. 2127-2134 ◽

Cited By ~ 1

Author(s):

František Potůček ◽

Jiří Stejskal

Keyword(s):

Mass Transfer ◽

Aqueous Solutions ◽

Transfer Coefficient ◽

Mass Transfer Coefficient ◽

Flow Rate ◽

Liquid Flow ◽

Flow Curve ◽

Liquid Flow Rate ◽

Polymer Concentration ◽

Newtonian Liquids

Absorption of oxygen into water and aqueous solutions of poly(acrylamides) was studied in an absorber with a wetted sphere. The effects of changes in the liquid flow rate and the polymer concentration on the liquid side mass transfer coefficient were examined. The results are expressed by correlations between dimensionless criteria modified for non-Newtonian liquids whose flow curve can be described by the Ostwald-de Waele model.

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Changes of Selected Structural and Mechanical Properties of the Strzelin Granites As Induced By Thermal Loads / Wpływ Obciążeń Termicznych Na Zmiany Niektórych Strukturalnych I Mechanicznych Właściwości Granitów Strzelińskich

Archives of Mining Sciences ◽

10.2478/v10267-012-0064-8 ◽

2012 ◽

Vol 57 (4) ◽

pp. 951-974 ◽

Cited By ~ 1

Author(s):

Andrzej Nowakowski ◽

Mariusz Młynarczuk

Keyword(s):

Mechanical Properties ◽

Nuclear Waste ◽

Structural Changes ◽

Structural Parameters ◽

Total Porosity ◽

Fracture Network ◽

Qualitative Description ◽

Temperature Changes ◽

Heating And Cooling ◽

Waste Repositories

Abstract Temperature is one of the basic factors influencing physical and structural properties of rocks. A quantitative and qualitative description of this influence becomes essential in underground construction and, in particular, in the construction of various underground storage facilities, including nuclear waste repositories. The present paper discusses the effects of temperature changes on selected mechanical and structural parameters of the Strzelin granites. Its authors focused on analyzing the changes of granite properties that accompany rapid temperature changes, for temperatures lower than 573ºC, which is the value at which the β - α phase transition in quartz occurs. Some of the criteria for selecting the temperature range were the results of measurements carried out at nuclear waste repositories. It was demonstrated that, as a result of the adopted procedure of heating and cooling of samples, the examined rock starts to reveal measurable structural changes, which, in turn, induces vital changes of its selected mechanical properties. In particular, it was shown that one of the quantities describing the structure of the rock - namely, the fracture network - grew significantly. As a consequence, vital changes could be observed in the following physical quantities characterizing the rock: primary wave velocity (vp), permeability coefficient (k), total porosity (n) and fracture porosity (η), limit of compressive strength (Rσ1) and the accompanying deformation (Rε1), Young’s modulus (E), and Poisson’s ratio (ν).

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Interfacial Aspects of Metal Matrix Composites Prepared from Liquid Metals and Aqueous Solutions: A Review

Metals ◽

10.3390/met10101400 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1400

Author(s):

Peter Baumli

Keyword(s):

Aqueous Solutions ◽

Physical Properties ◽

Metal Matrix Composites ◽

Metal Matrix ◽

Liquid Metals ◽

Interfacial Phenomena ◽

Matrix Composites ◽

Good Adhesion ◽

Mechanical And Physical Properties ◽

The Matrix

The paper reviews the preparation of the different metallic nanocomposites. In the preparation of composites, especially in the case of nanocomposites, interfacial phenomena play an important role. This review summarizes the literature on various interfacial phenomena, such as wettability and reactivity in the case of casting techniques and colloidal behavior in the case of electrochemical and electroless methods. The main contribution of this work lies in the evaluation of collected interfacial phenomena and difficulties in the production of metal matrix composites, for both nano-sized and micro-sized reinforcements. This study can guide the composite maker in choosing the best criteria for producing metal matrix composites, which means a real interface with good adhesion between the matrix and the reinforcement. This criterion results in desirable mechanical and physical properties and homogenous dispersion of the reinforcement in the matrix.

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Studies of 8-Quinolinethiol as Chelating Agents, III. Distribution Behavior of 8-Quinolinethiol between Chloroform and Aqueous Solutions

Bulletin of the Chemical Society of Japan ◽

10.1246/bcsj.55.1321 ◽

1982 ◽

Vol 55 (4) ◽

pp. 1321-1322 ◽

Cited By ~ 4

Author(s):

Eiichi Sekido ◽

Tadashi Kobayashi ◽

Yoshitaka Masuda

Keyword(s):

Aqueous Solutions ◽

Chelating Agents ◽

Distribution Behavior

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Experimental study and modeling of uranium (VI) transport through ferrous olivine rock columns

Radiochimica Acta ◽

10.1524/ract.2000.88.9-11.665 ◽

2000 ◽

Vol 88 (9-11) ◽

Cited By ~ 15

Author(s):

M. Rovira ◽

F.Z. El Aamrani ◽

L. Duro ◽

Ignasi Casas ◽

Joan de Pablo ◽

...

Keyword(s):

Nuclear Waste ◽

Reactive Transport ◽

Calculated Data ◽

Buffering Capacity ◽

Retardation Factor ◽

Reactive Transport Modeling ◽

Redox Active ◽

Different Types ◽

Free Media ◽

Waste Repositories

The Lovasjärvi intrusion (SE-Finland) contents a high percentage of ferrous olivine (> 65%). This material has been suggested as a redox-active backfill-additive in deep nuclear waste repositories, due to the large Fe(II) proportion in its mineral composition. In order to understand the processes involved in the redox buffering capacity of this material the transport of uranium (VI) through olivine columns was studied. The results showed considerable retardation factor for the U(VI), particularly in carbonate-free media. The experimental data were simulated by means of reactive transport modeling. The best agreement between the experimental and calculated data was obtained considering that the interaction of U(VI) with the olivine surface occurred at two different types of sorption sites. One type accounts for the sorption capacity of the olivine mineral, and a second type accounts for the sorption on amorphous Fe(OH)

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