Effects of La2O3 addition on the thermal stability of gamma-Al2O3 gels

The effects of La2O3 additions up to 5 wt.% on the thermal stabilities of sol-gel derived alumina gels were studied. Observations were made on pore size, total pore area, phase changes at various sintering temperatures and times. XRD, Hg-porosimeter, DTA-TG techniques were employed. The addition of La2O3 to the sol-gel derived alumina gels raised the gamma-Al2O3 to alpha-Al2O3 transformation temperature to 1200 degreesC. This significantly improves the thermal stabilities of alumina gels, that are employed in ceramic membranes. (C) 2003 Elsevier Ltd and Techna S.r.l. All rights reserved.