Variables in the synthesis of unusually high pore volume aluminas

摘要: This paper summarizes our successful efforts to obtain high pore volume aluminas (> 5.0 cm3 g−1 ). The volumes of these aerogels, prepared by the hydrolysis aluminium isopropoxide (AIP) in alcoholic media, are very sensitive amounts water and alcohol employed synthesis. An unexpectedly large ratio alkoxide yields highest volumes. By suitable selection initial levels alkoxide, methanol water, one obtains average 8.6 g−1. A two-step formulation AIP, methanol, followed hypercritical solvent removal form alumina aerogel Other alternative approaches also increase yield produced within autoclave. Pore about 7 result if premix is concentrated twofold after before autoclave processing. Lower reactant charge increased directly simply increasing concentration AIR It appears that reduction results part from higher isopropanol content final reaction mixture (isopropanol a co-product AIP hydrolysis).