Geochemistry of ultra-fine and nano-compounds in coal gasification ashes: a synoptic view.
Sci Total Environ
; 456-457: 95-103, 2013 Jul 01.
Article
em En
| MEDLINE
| ID: mdl-23584038
The nano-mineralogy, petrology, and chemistry of coal gasification products have not been studied as extensively as the products of the more widely used pulverized-coal combustion. The solid residues from the gasification of a low- to medium-sulfur, inertinite-rich, volatile A bituminous coal, and a high sulfur, vitrinite-rich, volatile C bituminous coal were investigated. Multifaceted chemical characterization by XRD, Raman spectroscopy, petrology, FE-SEM/EDS, and HR-TEM/SEAD/FFT/EDS provided an in-depth understanding of coal gasification ash-forming processes. The petrology of the residues generally reflected the rank and maceral composition of the feed coals, with the higher rank, high-inertinite coal having anisotropic carbons and inertinite in the residue, and the lower rank coal-derived residue containing isotropic carbons. The feed coal chemistry determines the mineralogy of the non-glass, non-carbon portions of the residues, with the proportions of CaCO3 versus Al2O3 determining the tendency towards the neoformation of anorthite versus mullite, respectively. Electron beam studies showed the presence of a number of potentially hazardous elements in nanoparticles. Some of the neoformed ultra-fine/nano-minerals found in the coal ashes are the same as those commonly associated with oxidation/transformation of sulfides and sulfates.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Sci Total Environ
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Holanda