Premium
Homogeneous Mullite‐Forming Powders from Spray‐Drying Aqueous Solutions
Author(s) -
Jaymes Isabelle,
Douy André
Publication year - 1992
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1992.tb04404.x
Subject(s) - mullite , spinel , aqueous solution , materials science , aluminium nitrate , homogeneous , chemical engineering , aluminium silicate , aluminium , colloid , thermal treatment , spray drying , mineralogy , metallurgy , composite material , chemistry , ceramic , organic chemistry , physics , engineering , thermodynamics
A mullite precursor solution was made by hydrolyzing TEOS in a diluted aqueous solution of aluminum nitrate. This solution was spray‐dried at a relatively low temperature (200°C), producing a chemically homogeneous powder crystallizing completely into mullite at 975°C. By aging this solution at 100°C, a diphasic precursor sol made of colloidal silica and aluminum nitrate was made. The resulting spraydried powder was less homogeneous, crystallizing into mullite and spinel or only spinel. The aging by thermal treatment may thus be a way to control the heterogeneity of the powder.