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Title: Chemical constraints on fly ash glass compositions

Abstract

The major oxide content and mineralogy of 75 European fly ashes were examined, and the major element composition of the glass phase was obtained for each. Correlation of compositional trends with the glass content of the ash was explored. Alkali content was deduced to have a major influence on glass formation, and this in turn could be related to the probable chemistry of clay minerals in the source coals. Maximal glass content corresponded to high aluminum content in the glass, and this is in accordance with the theoretical mechanism of formation of aluminosilicate glasses, in which network-modifying oxides are required to promote tetrahedral coordination of aluminum in glass chain structures. Iron oxide was found to substitute for alkali oxides where the latter were deficient, and some indications of preferred eutectic compositions were found. The work suggests that the proportion of the glass phase in the ash can be predicted from the coal mineralogy and that the utility of a given ash for processing into geopolymers or zeolites is determined by its source. 23 refs., 7 figs., 1 tab.

Authors:
;  [1]
  1. University of Dundee, Dundee (United Kingdom). Division of Civil Engineering
Publication Date:
OSTI Identifier:
20838263
Resource Type:
Journal Article
Resource Relation:
Journal Name: Energy and Fuels; Journal Volume: 20; Journal Issue: 6; Other Information: jbrind@balanus.fsnet.co.uk
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; FLY ASH; GLASS; CHEMICAL COMPOSITION; MINERALOGY; CORRELATIONS; ALKALI METAL COMPOUNDS; CLAYS; ALUMINIUM; EUTECTICS; WASTE PRODUCT UTILIZATION; ZEOLITES

Citation Formats

John H. Brindle, and Michael J. McCarthy. Chemical constraints on fly ash glass compositions. United States: N. p., 2006. Web. doi:10.1021/ef0603028.
John H. Brindle, & Michael J. McCarthy. Chemical constraints on fly ash glass compositions. United States. doi:10.1021/ef0603028.
John H. Brindle, and Michael J. McCarthy. Fri . "Chemical constraints on fly ash glass compositions". United States. doi:10.1021/ef0603028.
@article{osti_20838263,
title = {Chemical constraints on fly ash glass compositions},
author = {John H. Brindle and Michael J. McCarthy},
abstractNote = {The major oxide content and mineralogy of 75 European fly ashes were examined, and the major element composition of the glass phase was obtained for each. Correlation of compositional trends with the glass content of the ash was explored. Alkali content was deduced to have a major influence on glass formation, and this in turn could be related to the probable chemistry of clay minerals in the source coals. Maximal glass content corresponded to high aluminum content in the glass, and this is in accordance with the theoretical mechanism of formation of aluminosilicate glasses, in which network-modifying oxides are required to promote tetrahedral coordination of aluminum in glass chain structures. Iron oxide was found to substitute for alkali oxides where the latter were deficient, and some indications of preferred eutectic compositions were found. The work suggests that the proportion of the glass phase in the ash can be predicted from the coal mineralogy and that the utility of a given ash for processing into geopolymers or zeolites is determined by its source. 23 refs., 7 figs., 1 tab.},
doi = {10.1021/ef0603028},
journal = {Energy and Fuels},
number = 6,
volume = 20,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
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