scholarly journals Laboratory Testing of Waste Glass Aqueous Corrosion; Effects of Experimental Parameters

1993 ◽  
Vol 333 ◽  
Author(s):  
W.L. Ebert ◽  
J.J. Mazer
Keyword(s):  
Ion Exchange ◽  
Corrosion Rate ◽  
Laboratory Tests ◽  
Water Diffusion ◽  
Waste Glass ◽  
Solution Chemistry ◽  
Exchange Reactions ◽  
Glass Corrosion ◽  
Hydrolysis Reactions

ABSTRACTA literature survey has been performed to assess the effects of the temperature, glass surface area/leachate volume ratio, leachant composition, leachant flow rate, and glass composition (actual radioactive vs. simulated glass) used in laboratory tests on the measured glass reaction rate. The effects of these parameters must be accounted for in mechanistic models used to project glass durability over long times. Test parameters can also be used to highlight particular processes in laboratory tests. Waste glass corrosion results as water diffusion, ion exchange, and hydrolysis reactions occur simultaneously to devitrify the glass and release soluble glass components into solution. The rates of these processes are interrelated by the effects of the solution chemistry and glass alteration phases on each process, and the dominant (fastest) process may change as the reaction progresses. Transport of components from the release sites into solution may also affect the observed corrosion rate. The reaction temperature will affect the rate of each process, while other parameters will affect the solution chemistry and the particular processes that are observed during the test. The early stages of corrosion will be observed under test conditions which maintain dilute leachates and the later stages will be observed under conditions that generate more concentrated leachate solutions. Typically, water diffusion and ion exchange reactions dominate the observed glass corrosion in dilute solutions, while hydrolysis reactions are dominant in more concentrated solutions. Which process controls the long-term glass corrosion is not fully understood, and the long-term corrosion rate may be either transport- or reaction-limited.

Temperature Dependence of Long-Term Alteration Rate for Aqueous Alteration of P0798 Simulated Waste Glass under Smectite Forming Conditions

2006 ◽  
Vol 932 ◽  
Author(s):  
Y. Inagaki ◽  
T. Saruwatari ◽  
K. Idemitsu ◽  
T. Arima ◽  
A. Shinkai ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Temperature Dependence ◽  
Glass Surface ◽  
Water Diffusion ◽  
Waste Glass ◽  
Test Results ◽  
Aqueous Alteration ◽  
Simulated Waste ◽  
Controlling Processes

ABSTRACTSeveral kinetic models have been proposed to evaluate the aqueous dissolution/alteration rate of nuclear waste glass for long-term. However, reaction processes controlling the long-term rate are much more subjected to controversy. Temperature dependence of the long-term alteration rate is an essential issue to understand the rate controlling processes. In the present study, the static aqueous alteration tests were performed with a Japanese simulated waste glass P0798 as a function of temperature from 60°C to120°C, and the temperature dependence of the long-term alteration rate was evaluated to understand the rate controlling processes. The tests were performed in 0.001M NaOH solution to maintain a constant solution pH of around 10 during the test period and to provide smectite forming conditions where smectite forms as the major secondary phase without zeolite formation. From the test results on dissolution of boron, the alteration rate at each temperature was analyzed by use of a water-diffusion model. The water-diffusion model used is based on a simple assumption; the glass alteration is controlled by water diffusion with ion-exchange between water (hydronium ion: H3O+) and soluble elements (B, Na, Li, etc) at the glass surface layer with the apparent diffusion coefficient Di. A good agreement was observed between the model analysis and the test results, and the value of Di was evaluated to be 1.2 × 10−22 m2/s at 60°C to 1.8 × 10−21 m2/s at 120°C. The Arrhenius plot of Di showed a good linearity to give the activation energy of 49 kJ/mol, which value is close to that for the residual dissolution rate of French waste glass (53 kJ/mol) by Gin [1], and is very close to that for ion-exchange in sodium aluminosilicate glass (49 kJ/mol) by McGrail [2]. These results suggest that water diffusion with ion-exchange can be the dominant process controlling the alteration rate under smectite forming conditions. At elevated temperatures (100°C and 120°C), however, the model-predicted boron releases deviated from the experimental data at the later stage beyond 50-80 days, which suggests that the alteration layer developing at the glass surface may evolve to be protective against the water diffusion to depress the alteration rate as the alteration proceeds.

Ion-Exchange Interdiffusion Model with Potential Application to Long-Term Nuclear Waste Glass Performance

2016 ◽  
Vol 120 (17) ◽  
pp. 9374-9384 ◽  
Author(s):  
James Joseph Neeway ◽  
Sebastien N. Kerisit ◽  
Jia Liu ◽  
Jiandong Zhang ◽  
Zihua Zhu ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Nuclear Waste ◽  
Potential Application ◽  
Waste Glass ◽  
Nuclear Waste Glass

scholarly journals Surface Layer Effects on Waste Glass Corrosion

1993 ◽  
Vol 333 ◽  
Author(s):  
Xiangdong Feng
Keyword(s):  
Dissolution Rate ◽  
Waste Glass ◽  
Solution Chemistry ◽  
Secondary Phases ◽  
Transport Barrier ◽  
Water Contact ◽  
Chemical Attack ◽  
Glass Corrosion ◽  
Gel Layer ◽  
Surface Alteration

ABSTRACTWater contact subjects waste glass to chemical attack that results in the formation of surface alteration layers. Two principal hypotheses have been advanced concerning the effect of surface alteration layers on continued glass corrosion: (1) they act as a mass transport barrier and (2) they influence the chemical affinity of the glass reaction. In general, transport barrier effects have been found to be less important than affinity effects in the corrosion of most high-level nuclear waste glasses. However, they can be important under some circumstances, for example, in a very alkaline solution, in leachants containing Mg ions, or under conditions where the matrix dissolution rate is very low. The latter suggests that physical barrier effect may affect the long-term glass dissolution rate. Surface layers influence glass reaction affinity through the effects of the altered glass and secondary phases on the solution chemistry. The reaction affinity may be controlled by various precipitates and crystalline phases, amorphous silica phases, gel layer, or all the components of the glass. The surface alteration layers influence radionuclide release mainly through colloid formation, crystalline phase incorporation, and gel layer retention. This paper reviews current understanding and uncertainties.

Simulation of the Waste Glass Behavior in a Loamy Soil of the Wet Repository Site

2000 ◽  
Vol 663 ◽  
Author(s):  
M.I. Ojovan ◽  
N.V. Ojovan ◽  
I.V. Startceva ◽  
G.N. Chuikova ◽  
A.S. Barinov
Keyword(s):  
Borosilicate Glass ◽  
Field Data ◽  
Waste Glass ◽  
Loamy Soil ◽  
Model Calculations ◽  
Near Surface ◽  
Glass Corrosion ◽  
Radionuclide Release ◽  
Glass Behavior

ABSTRACTA model developed for description of waste glass corrosion has been applied to assess the radionuclide release from real radioactive (intermediate level) vitrified material over extended storage periods. Field data generated during the long-term testing of the prototype waste glass packages were mathematically processed and the derived parameters used in model calculations. Regardless of the corrosive saturated conditions of the wet near-surface repository, the fairly high safety of trench disposal has been demonstrated for borosilicate glass containing real NPP- operational waste.

Leaching Chemistry of Defense Borosilicate Glass

1982 ◽  
Vol 15 ◽  
Author(s):  
Richard M. Wallace ◽  
George G. Wicks
Keyword(s):  
Predictive Model ◽  
Borosilicate Glass ◽  
Waste Glass ◽  
Savannah River ◽  
Short Term ◽  
Glass Corrosion ◽  
Savannah River Plant ◽  
Plant Waste ◽  
Long Term Behavior

Studies of the leachability of waste glass have been in progress at Savannah River Laboratory (SRL) for several years. The principal objective of these studies has been to predict the long-term behavior of Savannah River Plant waste glass when stored in a repository. Such predictions can be made from the results of short-term tests only if the mechanisms of waste glass corrosion are understood. Determining the mechanisms of corrosion and developing a predictive model have therefore been a major thrust of our work.

scholarly journals Classifying the Biological Status of Honeybee Workers Using Gas Sensors

Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 166
Author(s):  
Jakub T. Wilk ◽  
Beata Bąk ◽  
Piotr Artiemjew ◽  
Jerzy Wilde ◽  
Maciej Siuda
Keyword(s):  
Gas Sensors ◽  
Laboratory Tests ◽  
Test Chamber ◽  
Ambient Air ◽  
True Positive Rate ◽  
True Positive ◽  
Positive Rate ◽  
Parameters Of Accuracy ◽  
Selection Of

Honeybee workers have a specific smell depending on the age of workers and the biological status of the colony. Laboratory tests were carried out at the Department of Apiculture at UWM Olsztyn, using gas sensors installed in two twin prototype multi-sensor detectors. The study aimed to compare the responses of sensors to the odor of old worker bees (3–6 weeks old), young ones (0–1 days old), and those from long-term queenless colonies. From the experimental colonies, 10 samples of 100 workers were taken for each group and placed successively in the research chambers for the duration of the study. Old workers came from outer nest combs, young workers from hatching out brood in an incubator, and laying worker bees from long-term queenless colonies from brood combs (with laying worker bee’s eggs, humped brood, and drones). Each probe was measured for 10 min, and then immediately for another 10 min ambient air was given to regenerate sensors. The results were analyzed using 10 different classifiers. Research has shown that the devices can distinguish between the biological status of bees. The effectiveness of distinguishing between classes, determined by the parameters of accuracy balanced and true positive rate, of 0.763 and 0.742 in the case of the best euclidean.1nn classifier, may be satisfactory in the context of practical beekeeping. Depending on the environment accompanying the tested objects (a type of insert in the test chamber), the introduction of other classifiers as well as baseline correction methods may be considered, while the selection of the appropriate classifier for the task may be of great importance for the effectiveness of the classification.

scholarly journals Ion Exchange Lithography: Localized Ion Exchange Reactions for Spatial Patterning of Perovskite Semiconductors and Insulators

2021 ◽  
pp. 2005291
Author(s):  
Lukas Helmbrecht ◽  
Moritz H. Futscher ◽  
Loreta A. Muscarella ◽  
Bruno Ehrler ◽  
Willem L. Noorduin
Keyword(s):  
Ion Exchange ◽  
Spatial Patterning ◽  
Exchange Reactions
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