Liquidus Temperature and Crystallization Behavior of US Waste Glasses Investigated at KRI

2009 ◽  
Vol 1193 ◽  
Author(s):  
Albert S. Aloy ◽  
Alexander V. Trofimenko ◽  
Valery Z. Belov ◽  
James C. Marra ◽  
Kevin M. Fox ◽  
...  
Keyword(s):  
Liquidus Temperature ◽  
Crystallization Behavior ◽  
Borosilicate Glasses ◽  
Savannah River ◽  
High Concentration ◽  
Optimization Study ◽  
Heat Treated ◽  
Waste Loading ◽  
River Site ◽  
Critical Process

AbstractAs a part of the optimization study for achieving the highest possible Hanford and Savannah River Site waste loading into acceptable borosilicate glasses, thirty glass compositions were selected for testing at KRI. These thirty test matrix glasses were designed to augment existing data within the compositional regions of interest with relatively high concentration of Al2O3 between 10 and 20 wt%.This paper reports experimental data on liquidus temperature (TL) and crystallization behavior of all synthesized glasses as well as durability of quenched and heat-treated glasses. The results of this study will be used to develop glass formulations for specific DOE waste streams to maintain or meet waste loading and/or waste throughput expectations while satisfying critical process and product performance related constraints.

Durabilities and Microstructures of Radioactive Glasses for Immobilization of Excess Actinides at the Savannah River Site

1995 ◽  
Vol 412 ◽  
Author(s):  
N. E. Bibler ◽  
W. G. Ramsey ◽  
T. F. Meaker ◽  
J. M. Pareizs
Keyword(s):  
Fission Product ◽  
Mass Spectroscopy ◽  
Savannah River Site ◽  
Borosilicate Glasses ◽  
Savannah River ◽  
Release Rates ◽  
The Third ◽  
Congruent Dissolution ◽  
Pu Isotopes ◽  
River Site

AbstractThis paper presents results of an investigation of the microstructures and durabilities of glasses for immobilization of excess Pu, Am, and Cm at the Savannah River Site (SRS). The glasses investigated had compositions based on commercial lanthanide glasses developed in the 1930's. All the glasses were prepared remotely in shielded cells and the analyses performed using instruments in radio hoods or benches. Durabilities were measured using the ASTM C-1285 standard leach test (PCT). Results for three glasses are presented. Two glasses contained 15 and 7 wt.% Pu, respectively. The third glass contained Am and Cm. The 15 wt% Pu glass was not completely amorphous and contained crystals of undissolved PuO2 and as well as dissolved PuO2. The 7 wt% Pu glass was completely amorphous. The Am/Cm glass contained <1 wt% actinides and was homogenous. The PCT tests for the Pu glasses indicated that B and Ba were leached congruently. Sm and Pu were leached at slower rates. In some cases release rates for specific Ba, Sm, and Pu isotopes were measured by analyzing the leachates by mass spectroscopy. For the Am-Cm glass release rates for B and Ba were equal indicating congruent dissolution. All three glasses were 25 to 50 times more durable than the borosilicate glasses developed at SRS for immobilization of the fission product HLW resulting from reprocessing operations at SRS.

Phase Formation in the Vitrification of Savannah River Site SB4 HLW Sludge Surrogate Using Frit and Glass Forming Chemicals

2009 ◽  
Vol 1193 ◽  
Author(s):  
O.I. Stefanovsky ◽  
S.V. Stefanovsky ◽  
A.A. Akatov ◽  
J.C. Marra
Keyword(s):  
Phase Formation ◽  
Savannah River Site ◽  
High Level Waste ◽  
Formation Mechanisms ◽  
Savannah River ◽  
Intermediate Phases ◽  
Heat Treated ◽  
Xrd Patterns ◽  
High Level ◽  
River Site

AbstractPhase formation mechanisms associated with the vitrification of Savannah River Site (SRS) Sludge Batch 4 (SB4) high level waste surrogate with high iron and aluminum contents were studied by infrared spectroscopy (IRS), X-ray diffraction (XRD) and optical microscopy. Two mixtures at 50 wt.% SB4 waste loading were prepared as slurries with a water content of ∼50 wt% using a waste surrogate and commercially available Frit 503-R4 (Li2O – 8 wt%, B2O3 – 16 wt%, SiO2 – 76 wt%) or mixture of chemicals (LiOH·H2O, H3BO3, SiO2). The mixtures were air-dried at a temperature of 115 °C and heat-treated at 500, 700, 900, 1000, 1100, 1200, and 1300 °C for 1 hr at each temperature. IR spectra and XRD patterns of the products heat-treated at each temperature were recorded. In both the mixtures phase formation reactions started at low temperatures and yielded intermediate phases (sodalite, pyroxene-type, nepheline), and the reactions were mostly completed within the temperature range between 1000 and 1100 °C. The glassy materials prepared at 1200 and 1300 °C were composed of vitreous phase and magnetite/trevorite type spinel.

Optimization of Savannah River M-Area Mixed Waste for Vitrification

1996 ◽  
Vol 465 ◽  
Author(s):  
Sabrina S. Fu ◽  
Hao Gan ◽  
Isabelle S. Muller ◽  
Ian L. Pegg ◽  
Pedro B. Macedo
Keyword(s):  
Chemical Durability ◽  
Waste Stream ◽  
Limiting Factor ◽  
Savannah River ◽  
Total Alkali ◽  
Optimization Study ◽  
Mixed Wastes ◽  
Waste Loading ◽  
Mixed Waste ◽  
Leaching Procedure

ABSTRACTVitrification studies of actual Savannah River M-Area mixed wastes have shown that the limiting factor for high waste loading of this waste stream is its chemical durability as defined by the toxicity characteristics leaching procedure (TCLP). As part of the optimization study of Savannah River M-Area wastes, a number of additives were examined including Na2O, Li2O, B2O3, ZrO2, and TiO2. This paper reports on the effect of varying the boron to total alkali ratio and on the effect of substitutions such as ZrO2 for waste and TiO2 for SiO2 on the chemical durability and processability of M-Area waste glasses.

Effect of Silver Content on the Crystalline Phase and Microstructure of TiO2 Coating Deposited on Unglazed Ceramics Tile

2020 ◽  
Vol 17 (3) ◽  
pp. 8179-8185
Author(s):  
N.Z. Hafizah ◽  
J. M. Juoi ◽  
M.R. Zulkifli ◽  
M.A. Musa
Keyword(s):  
Particle Growth ◽  
Dip Coating ◽  
Tio2 Coating ◽  
High Concentration ◽  
Ceramic Tiles ◽  
Soaking Time ◽  
Heat Treated ◽  
Ag Particles ◽  
Tio2 Sol ◽  
Almost All

The synthesis of Ag-TiO2 coating using AgNO3 precursor is expected to give the properties as pure as Ag nanoparticles. Commonly, high concentration of Ag attributed to agglomeration of silver species and reduction to Ag0 particles on TiO2 surface. In contrast, at lower concentration, Ag species exist as AgO, Ag2O and Ag0. Hence, the exact amount of Ag, which can effectively control the particle growth and agglomeration, surface area, thermal stability and band gap of the TiO2 coating, are still vague and stated differently. In the present study, the effect of Ag content on the phase transformation and surface morphology of Ag-TiO2 coating were reported. TiO2 sol were prepared by incorporating Ag at 2.5, 5 and 7.5 mol % and deposited on unglazed ceramic tiles thru five times dip coating. The deposited Ag-TiO2 coatings were heat treated at 500 °C for 1 hour soaking time. XRD analyses revealed that the deposited Ag-TiO2 coating consists of anatase, rutile, Ag2O and metallic Ag. Almost all the coating surfaces illustrated cracks. Increased Ag content lead to presence of tiny particles on the surfaces and EDX spectrum revealed the presence of Ti, O and metallic Ag particles. However, at the addition of 5 mol % Ag, there was no metallic Ag presence and a dense coating with the lowest thickness of ±11.4µm is observed.

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