Doctoral Dissertations
Keywords and Phrases
Dissolution behavior; Dissolution kinetics; Structure; Thermal stability
Abstract
"The solubility of phosphate glasses in aqueous solutions can be tailored through compositional control to obtain a wide range of ion release rates required for a variety of applications. The principal objective of this dissertation is to advance the understanding of the dissolution behavior of phosphate glasses in aqueous environments.
Two families of glasses, sodium-iron phosphate (NFP) glasses and sodium-calcium phosphate (NCP) glasses, were evaluated. The dissolution behavior depends on the phosphate anions that constitute the glass structure and the associated metal (Me) cations. The phosphate glass structure, defined by the distribution and average size of phosphate anions and depending on the O/P and Me/P ratios, was determined by high-pressure liquid chromatography and Raman spectroscopy; Mössbauer spectrometry provided information about the coordination environment of iron. This structural information is used to explain the compositional dependence of the thermal properties and crystallization tendency of NFP glasses and melts, and the aqueous corrosion behavior of NFP and NCP glasses.
Phosphate glass dissolution data are fit to different kinetic models which describe the glass dissolution mechanisms. Information about the glass composition and structure is used to predict changes in the pH of leachate solutions, and a model based on the Gibbs free energy of hydration used to explain the compositional dependence of the glass dissolution rates"--Abstract, page iv.
Advisor(s)
Brow, Richard K.
Committee Member(s)
Schlesinger, Mark E.
Day, D. E.
Fahrenholtz, William
Woelk, Klaus
Department(s)
Materials Science and Engineering
Degree Name
Ph. D. in Materials Science and Engineering
Publisher
Missouri University of Science and Technology
Publication Date
Fall 2014
Journal article titles appearing in thesis/dissertation
- Structural study of Na2--Fe--Fe2O--P2O5 glasses by high-pressure liquid chromatography
- Structural study of Na2O--FeO--Fe2O--P2O5 glasses by Raman and Mössbauer spectroscopy
- Crystallization behavior of Na2O--FeO--Fe2O3--P2O5 glasses
- Dissolution behavior of Na2O--FeO--Fe2O3--P2O5 glasses
- Dissolution behavior of Na2O--CaO--P2O5 glasses
- Dissolution behavior of Na2O--FeO--Fe2O3--P2O5 glasses in alkali aqueous solutions
Pagination
xiv, 218 pages
Note about bibliography
Includes bibliographical references.
Rights
© 2014 Li Na Ma, All rights reserved.
Document Type
Dissertation - Open Access
File Type
text
Language
English
Subject Headings
Glass-ceramics -- DissolutionPhosphatesGlass-ceramics -- StructureGlass-ceramics -- Thermal properties
Thesis Number
T 10615
Electronic OCLC #
902734900
Recommended Citation
Ma, Li Na, "Dissolution behavior of phosphate glasses" (2014). Doctoral Dissertations. 2349.
https://scholarsmine.mst.edu/doctoral_dissertations/2349