Mechanical Activation of Heterogeneous Sol–Gel Precursors for Synthesis of MgAl2O4 Spinel
Abstract:MgAl2O4 spinel precursor was prepared using a heterogeneous sol–gel process. The effect of high-energy milling on the precursor decomposition and spinel formation was investigated. The milling decreased the Al(OH)3 dehydroxylation temperature from 190° to about 130°C. The activation energy for spinel formation decreased from 688 kJ/mol for the as-prepared precursors to 468 kJ/mol for the precursors milled for 5 h. Milling of the precursor lowered the incipient temperature of spinel formation from 900° to 800°C, and the temperature of complete MgAl2O4 spinel formation from >1280° to ∼900°C.
Document Type: Communications
Affiliations: Department of Materials Engineering, University of British Columbia, Vancouver, BC, Canada V6T 1Z4
Publication date: October 1, 2005